Joint Water Purification Pilot Program. Pilot Study of Advanced Treatment Processes to Recycle JWPCP Secondary Effluent.

Transcription

1 Joint Wter Purifiction Pilot Progrm Pilot Study of Advnced Tretment Processes to Recycle JWPCP Secondry Effluent Finl Report A Joint Study by: Snittion Districts of Los Angeles County nd Metropolitn Wter District of Southern Cliforni September 28, 2012

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3 CONTENTS List of Figures... v List of Tbles... ix Acknowledgments... xii Executive Summry... xiii 1. Introduction Bckground on Advnced Wter Tretment Project Overview Objectives Test Loction Project Durtion nd Phsing Summry of Literture Review Report Orgniztion Description of Pilot System Overview of Pilot System Siemens Membrne Filtrtion (UF) Unit GE/Zenon MBR Unit Overview Aertion Tnk Membrne Tnk Permete Tnks Reverse Osmosis (RO) Pilot System Advnced Oxidtion Process (AOP) Trojn UV Mx G Rectors Clgon Ryox UV Rector Wter Qulity Smpling nd Testing Progrm Smpling Loctions Routine Smples Nitrosmines, 1,4--Dioxne, nd AOP Testing Title 22+ Smpling Wter Qulity Trgets i

4 4. System Opertion UF Tretment Tretment UF Opertion UF System Operting Prmeters UF System Performnce Dt Clening of the UF System RO Opertion UF-RO Operting Prmeters Optimiztion of UF-RO Operting Prmeters UF-RO System Performnce Dt Clening of the UF-RO System MBR Tretment Trin MBR Opertion MBR System Operting Prmeters MBR System Performnce Dt Clening of the MBR System RO Opertion MBR-RO Operting Prmeters Optimiztion of MBR-RO Operting Prmeters MBR-RO System Performnce Dt Clening of the MBR-RO System RO Autopsy Results Phse 1 Autopsies Phse 3 Autopsies Comprison of the UF nd MBR Trins UF vs MBR RO Units Summry UF UF-RO MBR MBR-RO ii

5 5. Wter Qulity Results: Generl Prmeters Compounds Removed with Solids Aluminum Brium Iron Phosphte Turbidity Biologicl Tretment by the MBR Ammoni nd TKN Nitrte Nitrite Alklinity COD TOC Constituents Removed Only by RO Boron Clcium Chloride Fluoride Mgnesium Potssium Silic Sodium Strontium Sulfte TDS Other Constituents TSS ph nd Temperture Summry iii

6 6. Wter Qulity Results: Nitrosmines nd 1,4-Dioxne JWPCP Secondry Effluent Tretment Trin #1: UF-RO-AOP UF Results RO Results AOP Results Removl of 1,4-Dioxne Removl of Nitrosmines Tretment Trin #2: MBR-RO-AOP MBR Results RO Results AOP Results Removl of 1,4-Dioxne Removl of Nitrosmines Comprison of LP nd MP UV Comprison of the UF nd MBR Trins Comprison of the UF nd MBR Comprison of the RO Permetes Comprison of the AOP Effluents Summry Wter Qulity Results: Title 22+ Prmeters JWPCP Secondry Effluent Tretment Trin #1: UF-RO-AOP UF Results RO Results AOP Results Tretment Trin #2: MBR-RO-AOP MBR Results RO Results AOP Results Comprison of the UF nd MBR Trins Comprison of the UF nd MBR Comprison of the RO Permetes Comprison of the AOP Effluents Summry iv

7 8. Summry Comprison of the UF nd MBR Opertions Wter Qulity Meeting Wter Qulity Tretment Gols Conclusions References Appendix A: Acronyms... A-1 Appendix B: Literture Review... B-1 Appendix C: Wter Qulity Prmeters nd Anlysis Methods... C-1 Appendix D: Membrne Autopsy Reports... D-1 Appendix E: Additionl Dt for Generl Wter Qulity Prmeters... E-1 Appendix F: Sttistics for Nitrosmines nd 1,4-Dioxne... F-1 Appendix G: Complete Title 22+ Dt... G-1 v

8 FIGURES 1-1. Pilot Plnt Loction t JWPCP Pilot Plnt Test Are Schemtic Digrm of Tretment Process Trins Siemens 12M10C Continuous Membrne Filtrtion Unit Schemtic Digrm of GE/Zenon MBR Pilot Plnt GE/Zenon Membrne Biologicl Rector RO Pilot System Configurtion RO Pilot Unit Schemtic Digrm of Trojn AOP System Trojn AOP System Clgon AOP System Schemtic Digrm of Smpling Loctions UF System Membrne Integrity UF System Feed nd Filtrte Pressure UF System TMP UF System Membrne Flux UF System Membrne Permebility UF System Clening Events During the First Hlf of Phse UF System Clening Events During the Second Hlf of Phse UF System Clening Events During Phse UF System Clening Events During the First Hlf of Phse UF System Clening Events During the Second Hlf of Phse UF-RO System Differentil Pressure Dt UF-RO System Temperture Dt UF-RO System Slt Pssge Over Time UF-RO System Slt Pssge s Function of Temperture UF-RO System Feed Pressure nd Temperture UF-RO System Normlized Specific Flux MBR System Influent Flow MBR System Flux MBR System HRT MBR System Temperture vi

9 4-21. MBR System MLSS MBR System SRT MBR System TMP MBR System Permebility MBR System TMP nd MLSS MBR-RO System Differentil Pressure MBR-RO System Temperture MBR-RO System Slt Pssge MBR-RO System Feed Pressure nd Temperture MBR-RO System Normlized Specific Flux MBR-RO System Feed Pressure nd Normlized Specific Flux After Shutdown Aluminum Concentrtions Brium Results Iron Results Phosphte Results Turbidity Results Ammoni Results TKN Results Nitrte Results Temperture Effects on Removl of Nitrte by RO Nitrite Results Totl Alklinity Results Comprison of Totl nd Soluble COD COD Results TOC Results Boron Results Boron Removls by RO Alone s Function of Time nd Temperture Clcium Results Chloride Results Fluoride Results Mgnesium Results Potssium Results Silic Results Silic Removls by RO Alone s Function of Time nd Temperture Sodium Results Strontium Results Sulfte Results TDS Results TSS Concentrtions Results for ph nd Temperture vii

10 6-1. Medin Concentrtions of Nitrosmines nd 1,4-Dioxne in Secondry Effluent Medin Concentrtions in UF Filtrte Medin Removls by UF Medin Concentrtions in UF-RO Permete Removls by RO Alone nd Combined UF nd RO AOP Removls of 1,4-Dioxne in UF-RO Permete AOP Removls of NDMA in UF-RO Permete AOP Removls of NDEA in UF-RO Permete AOP Removls of NDPA in UF-RO Permete Medin Concentrtions in MBR Permete Medin Removls by MBR Medin Concentrtions in MBR-RO Permete Removls by RO Alone nd Combined MBR nd RO Effect of Temperture on MBR-RO Removls of NDMA nd NDEA AOP Removls of 1,4-Dioxne in MBR-RO Permete AOP Removls of NDMA in MBR-RO Permete AOP Removls of NDEA in MBR-RO Permete Comprison of UF nd MBR Effluents Comprison of Removls by UF nd MBR Comprison of RO Permetes from UF nd MBR Trins Comprison of UF nd MBR Trins for RO nd Combined MBR nd RO Comprison of UF nd MBR Trins for Removl of 1,4-Dioxne by AOP Comprison of UF nd MBR Trins for Removl of NDMA by AOP Comprison of UF nd MBR Trins for Removl of NDEA by AOP viii

11 TABLES 1-1. Advnced Wter Tretment Fcilities in Southern Cliforni Opertionl Phses Siemens PVDF UF Membrnes GE/Zenon ZeeWeed Membrnes MBR Membrne Configurtion RO Pilot System Wter Qulity Prmeters: Smpling Frequency Summry of AOP Tsks Trget Effluent Concentrtions for Generl Physicl nd Minerl Prmeters, Trce Metls, nd Rdiologicl Anlytes Trget Effluent Concentrtions for Other Prmeters UF System: Flows, Fluxes, nd Mintennce Selected UF System Operting Dt by Phse UF Unit: Clening Intervls, Avilbility, Filtrte Production, nd Recover Averge Operting Conditions of UF-RO System Opertionl Phses of the MBR System Averge Operting Conditions of MBR System MBR Membrne Pcks in Service Restortion Clenings for the MBR Averge Operting Conditions of MBR-RO System Wter Qulity for the UF Trin Wter Qulity for the MBR Trin CDPH Tretment Requirements: UF Trin Hydrogen Peroxide Doses Required to Meet Tretment Gols: UF Trin CDPH Tretment Requirements: MBR Trin Hydrogen Peroxide Doses Required to Meet Tretment Gols: UF Trin Comprison of LP nd MP UV for Tretment of NDMA nd NDEA ix

12 7-1. Secondry Effluent: Generl Prmeters Secondry Effluent: Trce Metls, Rdiologicl Anlytes, nd Microbes Secondry Effluent: Trce Orgnic Constituents Secondry Effluent: Other Anlytes Results for UF Results for UF-RO Results for AOP (UF Trin) Results for MBR: Trce Metls, Rdiologicl Anlytes, nd Microbes Results for MBR: Other Anlytes Results for MBR-RO Results for AOP (MBR Trin) Comprison of UF nd MBR: Trce Metls, Rdiologicl Anlytes, nd Microbes Comprison of UF nd MBR: Other Prmeters Comprison of UF-RO nd MBR-RO Comprison of AOP Tretment on UF nd MBR Trins: Generl Prmeters, Trce Metls, nd Rdiologicl Anlytes Comprison of AOP Tretment on UF nd MBR Trins: Other Prmeters Comprison of UF nd MBR Effluent Concentrtions nd Trgets: Generl Prmeters, Trce Metls, nd Rdiologicl Anlytes Effluent Concentrtions nd Trgets: Other Prmeters Hydrogen Peroxide Doses Required to Meet AOP Tretment Gols x

13 ACKNOWLEDGMENTS This project ws funded by the Snittion Districts of Los Angeles County (Districts), the Metropolitn Wter District of Southern Cliforni, nd the US Bureu of Reclmtion. The project tem thnks these orgniztions for their finncil support of this pplied reserch. The project tem would lso like to cknowledge the ssistnce, efforts, nd dediction of the people who helped to mke this project possible: Leslie Clevelnd, Amy Witherll, nd Willim J. Steele for mnging the project t the US Bureu of Reclmtion Jodie Nygrd, Ry Trembly, nd Mike Sullivn for coordinting the dministrtion of the project t the Districts The Districts JWPCP nd SJC lbortories, for their help in coordinting, nlyzing, nd interpreting results for the thousnds of smples tken during the course of this project especilly Dwyne Fischer, Mri Png, Jen Lee, Greg Hoerner, Keith Mgers, Jun Guerrero, John Eng, Roger Lewis, Connie Young, nd Eric Nelson Ken Smith, Rymond Bughn, Nichols Gutierrez, nd Fernndo Lx of the Districts for constructing nd mintining the pilot system infrstructure Philip L. Friess, Robert Ferrnte, Grce R. Chn, nd Stephen R. Mguin of the Districts for their support of the project Jmes Peterson, formerly with GE, for vluble discussions nd input on configuring nd operting the tertiry MBR John Kutilek nd Scott Beech of Siemens Wter Technologies for technicl dvice s well s onsite nd remote service ssistnce Dvid DesRochers, Keith Bircher, nd other stff t the Clgon Crbon Corportion, s well s Trn Victor t JBI Wter nd Wstewter Equipment, for their ssistnce with the Clgon UV unit. Principl Investigtors nd Project Mngers Chi-Chung Tng, PhD., PE, BCEE, Snittion Districts of Los Angeles County Sun Ling, Ph.D., PE, Metropolitn Wter District of Southern Cliforni Project Tem Snittion Districts of Los Angeles County Robert Morton, PE, BCEE Jmes J. Brry, PE Thoms E. Knpp, PE Noko Munkt, PhD, PE Nichols Sml, PE Lrry Wong, PE Metropolitn Wter District of Southern Cliforni Christopher J. Gbelich, PhD. xi

14 EXECUTIVE SUMMARY Bckground This pilot project ws prt of lrger effort to evlute the fesibility of regionl indirect potble reuse progrm, which would purify secondry effluent to meet the replenishment needs of locl groundwter bsins in Southern Cliforni. The work ws conducted between 2010 nd 2012 by the Snittion Districts of Los Angeles County (Districts) nd the Metropolitn Wter District of Southern Cliforni (MWD) t the Districts Joint Wter Pollution Control Plnt (JWPCP) in Crson, CA. The JWPCP hs n verge dry wether design flow of 400 million gllons per dy (MGD), nd currently trets pproximtely 280 MGD of wstewter. Tretment processes include screening, grit removl, primry sedimenttion, high purity oxygen ctivted sludge process, chlormine disinfection, sludge thickening, nerobic digestion, nd dewtering. Treted effluent is currently dischrged to the Pcific Ocen. Objectives The overll gol of this study ws to test dvnced wter tretment (AWT) processes nd to determine whether the product wter could meet or exceed the groundwter rechrge wter qulity criteri specified in Cliforni Deprtment of Public Helth (CDPH) 2008 Drft Title 22 Groundwter Rechrge Regultions (DGRR) nd other pplicble regultory limits. Two tretment trins were studied. One consisted of the industry-stndrd system of ultrfiltrtion (UF), reverse osmosis (RO), nd n dvnced oxidtion process (AOP) with ultrviolet (UV) oxidtion nd hydrogen peroxide ddition. The other consisted of membrne biorector (MBR) followed by RO nd UV/hydrogen peroxide AOP. The specific tsks of the study were the following: Conduct review of similr wter recycling projects documenting the experiences of these projects, including membrne opertion nd tretment of trget contminnts. Chrcterize effluent nd concentrte wter qulity from both AWT process trins. Compre effluent wter qulity to criteri specified in 2008 CDPH DGRR nd other pplicble regultory limits. Evlute UV oxidtion, with nd without hydrogen peroxide ddition, for tretment of compounds tht re not completely removed by RO membrnes. Evlute operting conditions nd performnce of the AWT membrne processes. Determine the effect of biologicl nitrifiction on system opertions nd product wter qulity. Evlute chemicls/dditives (specificlly chlormines, nti-sclnts, nd cids) necessry for membrne fouling control. xii

15 Pilot System Description The ultrfiltrtion unit used for this project ws Siemens 12M10C continuous filtrtion unit. This pressurized membrne filtrtion unit utilized hollow-fiber polyvinylidene fluoride (PVDF) membrnes with nominl membrne pore size of 0.04 µm. The MBR unit used for this project ws GE/Zenon pilot system. ZeeWeed 500c hollow fiber membrnes (PVDF with nominl pore size of 0.04 µm) were used for the first yer of the study. These membrnes, which hd been used by the Districts for vrious studies since 2003, were replced with new ZeeWeed 500d membrnes (lso PVDF with nominl pore size of 0.04 µm) t the end of The UF filtrte nd MBR permete were used s feed strems for the RO units. Two identicl RO units were used in the study, ech equipped with 21 Hydrnutics ESPA2 membrne elements configured in two-stge 2:2:1:1 rry. Stge 1 vessels contined 14 elements (two prllel series of seven elements) while Stge 2 vessels contined seven elements in series. The AOP system could be fed with either UF-RO permete or MBR-RO permete. Most of the AOP testing used three flow-through Trojn UV Mx G rectors, ech equipped with single 100W low-pressure high-output mlgm lmp tht emitted monochromtic rdition t wvelength of 254 nm. In selected experiments, Clgon Crbon Ryox btch UV rector ws used. This rector could be equipped with single 40W low-pressure high-output lmp with monochromtic output t 254 nm, or single 1kW medium-pressure lmp tht emitted polychromtic rdition. Hydrogen peroxide could be dded to the influent strem of the Trojn rectors, or directly to the Clgon rector. Wter Qulity Smpling Progrm Smpling progrms were estblished for three sets of wter qulity prmeters: generl prmeters, nitrosmines nd 1,4-dioxne, nd comprehensive set of prmeters referred to s Title 22+ prmeters. The generl prmeters were routinely smpled nd were used to evlute the performnce of the vrious pilot units. The nitrosmines nd 1,4-dioxne were seprted from the other prmeters in this report, becuse the removl requirements for these compounds typiclly drive the design of the AOP system; consequently, the AOP experiments focused on these compounds. The Title 22+ prmeters provided performnce dt for much broder rnge of compounds thn the generl prmeters. The first set of prmeters included physicl prmeters (ph, turbidity, totl suspended solids, nd totl dissolved solids), mjor ctions (clcium, mgnesium, sodium, nd potssium) nd nions (sulfte, chloride, nd lklinity), orgnic mtter (totl nd soluble COD, TOC), nutrients (mmoni, nitrte, nitrite, totl Kjeldhl nitrogen, phosphte), nd other prmeters of interest (boron, luminum, iron, brium, silic, strontium, nd fluoride). Secondry effluent, UF filtrte, MBR permete, nd RO permetes smples were collected from the two AWT process trins nd nlyzed for these compounds. The smpling frequency vried from dily to bi-weekly depending on the smpling loction nd prmeter. Concentrte strems produced from RO opertions were smpled on qurterly bsis for the sme list of prmeters. The second set of prmeters included 1,4-dioxne nd seven nitrosmine species: N-nitrosodimethylmine (NDMA), N-nitrosodiethylmine (NDEA), N-nitrosodi-n-propylmine xiii

16 (NDPA), N-nitrosodi-n-butylmine (NDBA), N-nitrosomethylethylmine (NMEA), N-nitrosopiperidine (NDPA), nd N-nitrosopyrrolidine (NPYR). These eight compounds were nlyzed in bi-weekly smples tken from the secondry effluent, UF filtrte, MBR permete, nd both RO permetes. Smples were lso tken during AOP experiments. The Title 22+ prmeters were set of 299 prmeters tht included ll of the bove prmeters, s well s rdioctive nlytes, UV trnsmittnce, microbiologicl prmeters, voltile nd semi-voltile orgnic compounds, pesticides, herbicides, disinfection byproducts, hormones, industril endocrine disrupting chemicls (EDCs) nd phrmceuticl nd personl cre products (PPCPs). A totl of six Title 22+ smpling events were conducted in the study; two on the UF tretment trin nd four on the MBR tretment trin. Pilot System Opertions Opertion of the pilot-scle system begn in June 2010 nd ended in June The study ws divided into three phses, which were defined by the operting conditions on the MBR nd the RO units (described in more detil in the following prgrphs). Phse 1 for the UF tretment trin begn in July Becuse the MBR system required more modifictions before opertion, Phse 1 for the MBR trin begn in December Phse 1 for both tretment trins ended in Mrch Phse 2 opertions begn in July 2011 nd ended in December Phse 3 begn in Jnury 2012 nd ended with the end of the project in June The UF unit ws operted t constnt flux of pproximtely 22 gllons per squre foot per dy (gfd), or flow rte of 46 gllons per minute (gpm). Averge recovery ws 93%. The unit ws in productive opertion (producing filtrte) for 13,700 hours over 726 dys of testing, nd treted more thn 40 million gllons of secondry effluent. For pproximtely two yers, the unit performed relibly nd provided dequte feed for RO tretment. Two types of clening were routinely conducted during the study. The chemiclly enhnced bckwsh (CEB) ws single bckwsh with sodium hypochlorite solution, followed by 15- to 30-minute sok. Clen-inplce (CIP) consisted of recirculting nd soking the membrnes in citric cid nd sodium hypochlorite solutions. In the first two opertionl phses of the study, membrne clening intervls were cceptble with CIP required no more frequently thn bout every four weeks nd CEBs not needed more thn weekly. In Phse 3, however, the necessry CIP frequency incresed to bout every two weeks, nd CEBs were required lmost on dily bsis. Membrne fouling ppered to be worse during the winter, nd lso during rin events, when the solids content of the secondry effluent ws noticebly higher. At the end of the two-yer study period, the UF membrnes were permnently fouled. The MBR polished secondry effluent, with both biologicl tretment nd membrne filtrtion, to provide feed for RO tretment. In Phses 1 nd 2, ZeeWeed 500c membrnes (originlly instlled nd used in 2003) were operted t fluxes rnging from 10 to 15 gfd. The mixed liquor suspended solids concentrtion in the membrne tnk ws mintined between 3,000 to 4,000 mg/l. The MBR ws operted t solids retention times (SRTs) >10 dys, nd t hydrulic retention times rnging from pproximtely 70 to 100 minutes. The system performed dequtely over the study period except ner the end of Phse 2 when membrnes pproched the end of their service life nd becme significntly fouled. New ZeeWeed 500d membrnes were used in Phse 3 nd operted t 20 gfd. No significnt fouling on the new membrnes hd occurred by the end of the study in June xiv

17 Both RO units were operted t n verge flux of 12 gfd, nd verge recovery of pproximtely 85%. In Phse 1 opertion, sulfuric cid ws dded to lower the RO influent to trget ph of 6.5. The verge sulfuric cid doses required for the UF filtrte nd MBR permete were 162 mg/l nd 53 mg/l, respectively. At the end of Phse 1 opertion, membrne elements from both RO units were extrcted for utopsy. A deep clening of the RO membrnes ws then performed prior to Phse 2. In Phse 2 opertion, sulfuric cid ddition ws reduced bsed on the Lngelier sturtion index of the RO concentrte. The trget ph of the concentrte ws set to be 7.2 for the UF-RO nd 7.3 for the MBR-RO. The chnge resulted in 40% reduction of sulfuric cid usge for the UF-RO tretment trin, nd 95% reduction for the MBR-RO tretment trin. In Phse 3, new membrne elements were used for both RO units becuse wter qulity dt collected from Phse 2 nd membrne utopsy results both suggested tht the RO membrnes were fouled nd might hve been dmged. Wter Qulity Smpling Results Generl Prmeters The JWPCP produced non-nitrified secondry effluent with the following chrcteristics (medin vlues): totl COD ~55 mg/l (~85% soluble), TSS ~10 mg/l, TDS ~1,400 mg/l, nd TKN ~ 40 mg N/L. Secondry effluent concentrtions of severl generl prmeters (brium, boron, chloride, phosphte, strontium, sulfte, TOC, TSS, lklinity, mmoni nd TKN, totl nd soluble COD, nd potssium) incresed during the study period. The UF effectively removed TSS, turbidity, nd nlytes (such s luminum nd iron), tht were ssocited with solids. Some brium, phosphte, nd prticulte COD were lso removed by UF. In ddition to removing solids, the MBR removed n verge of 40% of orgnic mtter (COD nd TOC) from the secondry effluent nd completely nitrified TKN to mostly nitrte nitrogen. The nitrifiction process consumed pproximtely three-qurters of the secondry effluent lklinity. Consequently, the sulfuric cid dose required to lower the MBR permete to the trget ph of the RO feed ws much less thn tht required for the UF filtrte. Due to the sulfuric cid ddition, the medin ph vlues were 5.5 nd 5.6 in the UF-RO nd MBR- RO permetes, respectively. Becuse these vlues were lower thn the trget rnge of , the RO permete would likely need to be treted (e.g., with decrbontion nd lime) to rise the ph, s is typicl for AWT systems. The RO units effectively removed the mjority of the generl wter qulity prmeters except boron (15-50% removl). Boron ws present in the RO permetes of both tretment trins t concentrtions s high s 0.8 mg/l; the Min Sn Gbriel Bsin Pln (Bsin Pln) objective concentrtion for boron is 0.5 mg/l. Source control or other tretment technologies, such s ion exchnge, would be required to meet the Bsin Pln objective for boron. For the UF-RO tretment trin, the medin totl nitrogen (TN) level in the RO permete ws ~2 mg N/L nd consisted minly of mmoni nitrogen. The medin TN level in the RO permete for the MBR-RO tretment trin ws ~3 mg N/L nd consisted minly of nitrte nitrogen. TOC levels in the UF-RO permete occsionlly exceeded the 0.5 mg/l trget in Phses 1 nd 2, but consistently met the trget in Phse 3. TOC concentrtions in the MBR-RO permete were consistently below 0.5 mg/l throughout the study. xv

18 Nitrosmines nd 1,4-Dioxne In secondry effluent, five nitrosmines (NDMA, NDEA, NDPA, NDBA, nd NPIP) were typiclly present t levels greter thn 100 ng/l, nd 1,4-dioxne level ws typiclly ~10 µg/l. The UF hd very little effect on ny of these compounds except NDEA, which incresed in concentrtion cross the UF. The MBR hd little effect on 1,4-dioxne, but consistently removed NDPA, NPIP, nd NPYR. NDMA nd NDBA were removed to lesser degree, nd the removls were not consistently significnt. Similr to the UF, the concentrtions of NDEA incresed cross the MBR. Further reserch is needed to determine the cuse(s) of this increse. The RO membrnes were effective t removing most of the compounds to below the trget concentrtions. The exceptions were NDMA nd NDEA, with concentrtions consistently bove trget levels, nd NDPA nd 1,4-dioxne, with concentrtions occsionlly bove trget levels. AOP testing ws conducted to determine the conditions under which these four compounds could be removed to below the trget concentrtions. Becuse concentrtions entering the AOP vried, tretment gols were set s trget removls, bsed on the highest observed RO permete concentrtions nd the trget concentrtion. The AOP successfully chieved trget removls of 1,4-dioxne, NDMA, nd NDPA. However, NDEA trgets were not chieved t the tested doses (up to 6 mg/l of hydrogen peroxide nd up to 4 kwh/kgl of UV; this UV dose is rector-specific nd does not pply to ny other system). The NDEA removl trgets could be met by incresing the doses, by reducing the influent concentrtions through source control, nd/or by choosing different influent concentrtion (e.g., the 90 th percentile, rther thn the mximum vlue) for design. The levels of removl of the vrious compounds were not ffected by hydrogen peroxide lone. NDMA removl incresed with incresing UV dose, but hydrogen peroxide hd no effect on removl. Removls of NDEA, NDPA, nd 1,4-dioxne incresed with incresing doses of either UV or hydrogen peroxide. Removls were slightly better in the MBR-RO effluent thn in the UF-RO effluent, which could result in lower hydrogen peroxide doses (by 1-2 mg/l) to meet regultory removl requirements. The LP lmps provided cler benefit over the MP lmps, with better removl of both NDMA nd NDEA t lower UV doses (i.e., lower energy use). Title 22+ Prmeters A totl of 299 prmeters were tested in six Title 22+ smpling events. In ddition to the generl prmeters, nitrosmines, nd 1,4-dioxne discussed bove, the JWPCP secondry effluent contined trce levels of voltile orgnic compounds (VOCs, e.g., chloroform nd phenol), pesticides (e.g., ldicrb sulfone), hormones (e.g., estrone), industril EDCs (e.g., bisphenol A nd lkylphenols), nd PPCPs (e.g., sulfmethoxzole nd DEET), nd other wstewter indictors (e.g., cffeine nd TCEP). Excluding the generl prmeters, nitrosmines, nd 1,4- dioxne discussed bove, the UF-RO tretment effectively removed ll detected chemicls to below their lbortory reporting limits except for severl VOCs, chlorte, nd formldehyde. The detected levels of these prmeters were well below their trget concentrtions, for those compounds tht hd trget concentrtions. The MBR-RO tretment trin performed similrly, except tht chlorte ws not detected nd the species of some VOCs differed. xvi

19 The AOP processes performed similrly on both trins. Low levels of severl metls (copper, led, nd hexvlent chromium) were detected in the AOP effluent from both tretment trins. This ws likely due to contmintion from the UV rectors or fittings becuse these metls were not detected in the RO permetes. Formldehyde concentrtions incresed for both effluents, but remined well below the trget concentrtion of 100 g/l. The totl THM concentrtions in the AOP effluent were slightly lower in the MBR trin thn in the UF trin, but concentrtions in both effluents were well below the totl THM trget concentrtion of 80 g/l. Overll, the Title 22+ smpling results indicted tht both AWT trins were effective in removing the trce contminnts present in the JWPCP secondry effluent to either below the lbortory reporting limits or the relevnt trget concentrtions. With the exception of boron, NDEA, nd ph, the finl product wter from both AWT trins met ll of the wter qulity trgets for groundwter replenishment. Comprison of AWT Process Trins Opertion UF-RO-AOP Opertions of UF ws more ffected by the secondry effluent wter qulity; poor secondry effluent wter qulity incresed the chnce of fouling nd the clening requirements MBR-RO-AOP Opertion of MBR ws less ffected by secondry effluent wter qulity; MBR operted to polish secondry effluent could be operted t flux similr to the UF flux Design Required smller footprint Required ertion tnk(s) s well s membrne tnk(s) Chemicl Use Energy Use Effluent Wter Qulity Sulfuric cid dose to lower the ph of UF filtrte ws higher Energy to operte the UF system ws lower Medin totl nitrogen concentrtion ws ~2 mg NH 3 -N/L TOC concentrtion ws occsionlly higher thn the trget of 0.5 mg/l Sulfuric cid dose to lower the ph of MBR permete ws much lower becuse the MBR consumed 75% of the secondry effluent lklinity during nitrifiction MBR system required ir scouring of the membrnes, therefore using more energy; ir used for membrne scouring ws sufficient to fully nitrify the secondry effluent in this study Medin totl nitrogen concentrtion ws ~3 mg NO 3 -N/L TOC concentrtion ws consistently below the trget of 0.5 mg/l AOP removl of nitrosmines nd 1,4-dioxne ws slightly better becuse of lower lklinity nd/or higher UVT in the RO permete. xvii

20 Conclusions With JWPCP secondry effluent s the source wter, the UF-RO-AOP process trin produced high qulity recycled wter tht consistently met the wter qulity criteri in 2008 CDPH DGRR except for TOC. TOC concentrtions in the finl product wter occsionlly exceeded the DGRR limit of 0.5 mg/l. In ddition, boron concentrtions in the finl product wter often exceeded the Bsin Pln limit of 0.5 mg/l. Source control or dditionl tretment processes would be required to lower the boron concentrtion to below this limit if the finl product wter ws to be used for groundwter replenishment. Finlly, the ph ws lower thn the trget of ; the RO permete would likely need to be treted (e.g., with decrbontion nd lime) to rise the ph, s is typicl for AWT systems. The AOP tested in the study ws effective in removing emerging contminnts of concern such s nitrosmines nd 1,4-dioxne. The required UV nd hydrogen peroxide doses would be determined bsed on NDEA removl requirements. The MBR-RO-AOP process trin proved to be n intriguing lterntive to the UF-RO- AOP process trin. UF membrnes used for treting secondry effluent from low SRT ctivted sludge process often suffer from fouling problems, s observed in this study. The MBR could be operted to polish the secondry effluent by removing biodegrdble orgnic mtter nd reducing the potentil for membrne fouling. In this study, the MBR membrnes were operted t flux comprble to tht of the UF membrnes for pproximtely six months (Phse 3). There were no membrne fouling problems during this time period. More time would be required to verify tht the MBR could be operted under these conditions without fouling. The MBR-RO-AOP process trin lso produced high qulity recycled wter tht consistently met the wter qulity criteri in 2008 CDPH DGRR, including TOC. Boron concentrtions in the finl product wter often exceeded the Bsin Pln limit of 0.5 mg/l. Source control or dditionl tretment processes would be required to lower the boron concentrtion to below this limit if the finl product wter ws to be used for groundwter replenishment. In ddition, the ph ws lower thn the trget of ; the RO permete would likely need to be treted (e.g., with decrbontion nd lime) to rise the ph. The AOP tested in the study ws effective in removing emerging contminnts of concern such s nitrosmines nd 1,4-dioxne. The required UV nd hydrogen peroxide doses would be determined bsed on NDEA removl requirements. Decresing NDEA concentrtions in the RO permete would reduce the size nd cost of the AOP system t the JWPCP. NDEA ws present in the secondry effluent, nd its concentrtion incresed cross both the UF nd MBR units. The increse cross the UF my be due to chlormintion of the secondry effluent, but the MBR permete smples were not chlorminted. More work is needed to better understnd the formtion mechnisms of NDEA. xviii

21 1. INTRODUCTION 1.1 BACKGROUND ON ADVANCED WATER TREATMENT Advnced wter tretment technologies hve been successfully used in number of wter recycling projects. These projects typiclly include microfiltrtion (MF) or ulftrfiltrtion (UF) followed by reverse osmosis (RO), nd dvnced oxidtion processes (AOP) where required. Tble 1-1 summrizes wter recycling fcilities in Southern Cliforni, the types of membrnes used, design fluxes, nd pplictions. Typicl operting conditions for MF/UF membrnes treting secondry effluent re gllons per squre foot per dy (gfd) flux nd 85-93% recovery. These operting conditions typiclly ensure effluent qulity tht cn yield gfd flux nd 85% recovery for downstrem RO membrnes. At most fcilities, biofouling of both MF/UF nd RO membrnes is controlled through the use of chlormines. Commercilly vilble nti-sclnts nd other chemicls re used on RO membrnes to control inorgnic fouling cused by springly soluble slts. 1.2 PROJECT OVERVIEW The Joint Wter Purifiction Pilot Progrm ws collbortive effort between the Snittion Districts of Los Angeles County (Districts) nd the Metropolitn Wter District of Southern Cliforni (MWD). The objective of the project ws to evlute the fesibility of regionl indirect potble reuse progrm to purify treted wstewter from the Districts Joint Wter Pollution Control Plnt (JWPCP) tht is currently dischrged to the Pcific Ocen. The purified wter produced would be conveyed either through distribution system to meet replenishment needs of multiple locl groundwter bsins or to single groundwter bsin tht would ct s n environmentl buffer prior to recovery nd blending with rw wter influent to one or more MWD tretment plnts. As prt of the progrm, the Districts nd MWD initited Pilot Study of Advnced Tretment Processes to Recycle JWPCP Secondry Effluent to test dvnced wter tretment (AWT) processes nd to determine the requirements to chieve wter qulity tht surpssed drinking wter stndrds. Two prllel AWT process trins were tested to determine their effectiveness in producing recycled wter tht met or exceeded the groundwter rechrge wter qulity criteri specified in Title 22 of the Cliforni Code of Regultions. One AWT process trin consisted of the industrystndrd system of UF/RO/AOP, which is employed by severl gencies in Southern Cliforni (Tble 1-1). The second AWT process trin consisted of membrne biorector (MBR) followed by RO nd AOP. MBRs typiclly tret rw sewge or primry effluent. However, this pilot MBR ws operted s tertiry MBR tht polished secondry effluent nd produced nitrified permete s RO feed. Prior to this project, tertiry MBR hd been pilot-tested once, to improve nutrient removl nd expnd conventionl wstewter tretment plnt in Hmilton, Ontrio, Cnd (Constntine, et l., 2010); however the ppliction of tertiry MBR s RO pretretment ws novel nd hd not been tested previously. Similr to the UF, this MBR provided permete filtered through UF membrnes; however, the MBR lso provided biologicl nitrifiction of the effluent, which offered potentil dvntges over UF. 1

22 Tble 1-1. Advnced Wter Tretment/Reclmtion Fcilities in Southern Cliforni 2 Agency Plnt Source Wter Crlsbd MWD Exxon- Mobil LADPW WBMWD OCWD WBMWD Crlsbd Wter Recycling Exxon- Mobil WRF Terminl Islnd CRWRF GWRS El Segundo, Phse I Yer Strted Cpcity (MGD) MF/UF Membrne MF/UF Flux (gfd) Encin WPCF Siemens PP 35 EC Little WRP, tertiry Terminl Islnd, tertiry EC Little WRP, tertiry OCSD Plnt 1, secondry Hyperion, secondry Siemens PP Siemens Memcor PP Siemens PP Siemens PP Siemens PP 18 RO Membrnes Hydrnutics ESPA 2 Hydrnutics ESPA 2 Hydrnutics ESPA 2 Hydrnutics ESPA 2 Hydrnutics ESPA 2 Hydrnutics ESPA 2 RO Flux (gfd) AOP NA None NA 10 None Boiler feed Use 10 None Sewter brrier 12 None BP boiler feed 12 Trojn UV + peroxide Groundwter rechrge; sewter brrier 12 None Sewter brrier WBMWD El Segundo, Hyperion, Hydrnutics Siemens PP 18 Phse II secondry ESPA 2 12 None Sewter brrier WBMWD El Segundo, Hyperion, Hydrnutics Siemens PP 18 Phse III secondry ESPA 2 12 None Chevron boiler feed WBMWD El Segundo, Hyperion, Hydrnutics Trojn UV Siemens PP Phse IV secondry ESPA 2 + peroxide Sewter brrier WRD Leo Vnder Long Bech Pll Microzo Hydrnutics Ground-wter Trojn UV Lns WRP, Tertiry PVDF ESPA 2 rechrge GWRS: Groundwter Replenishment System; LADWP: Los Angeles Deprtment of Public Works; OCSD: Ornge County Snittion District; OCWD: Ornge County Wter District; PP: Polypropylene; PVDF: Polyvinylidene Fluoride; WBMWD: West Bsin Municipl Wter District; WPCF: Wter Pollution Control Fcility; WRD: Wter Replenishment District; WRF: Wter Reclmtion Fcility; WRP: Wter Reclmtion Plnt.

23 Biologicl ctivity in the MBR my reduce levels of orgnics nd other compounds of concern, nd provide higher qulity wter for RO nd AOP. This dditionl tretment (nd the fct tht the MBR membrnes re designed to operte in solution with reltively high solids nd orgnics) my lso reduce fouling, which hs been n issue in some full-scle UF systems. In ddition, nitrifiction is known to consume lklinity nd lower ph, both of which reduce cid requirements (nd thus, chemicl costs) for the downstrem RO process. Finlly, lklinity is known scvenger of the hydroxyl rdicls tht re ctive in AOPs; therefore, the reduction in lklinity hs the potentil to lso improve the performnce of the downstrem AOPs. These potentil dvntges nd cost svings my more thn offset the incresed cost nd complexity of using MBR for RO pretretment, reltive to using UF. 1.3 OBJECTIVES The min objective of the pilot progrm ws to evlute the bility of the two AWT process trins to tret JWPCP secondry effluent nd produce purified recycled wter tht met or exceeded the groundwter rechrge wter qulity criteri specified in Cliforni Deprtment of Public Helth (CDPH) 2008 Drft Title 22 Groundwter Rechrge Regultions (DGRR). Note tht newer drft ws relesed in November 2011; however, the trgets in this report re lrgely bsed on the 2008 DGRR requirements. An dditionl objective ws to evlute the opertionl performnce of the AWT technologies tht comprise the process trins. The specific tsks of the study were the following: 1. Conduct review of similr wter recycling projects documenting the experiences of these projects (e.g., design criteri, operting chllenges, relibility, etc.) including membrne opertion nd tretment of trget contminnts (e.g., N-nitrosodimethylmine, NDMA, nd 1,4-dioxne). 2. Chrcterize effluent nd concentrte wter qulity from both AWT process trins; wter qulity prmeters of interest include TOC, nitrogen compounds, disinfection byproducts (DBPs), phrmceuticls nd personl cre products, pesticides, herbicides, nd other voltile nd semi-voltile compounds. Compre effluent wter qulity to criteri specified in 2008 CDPH DGRR nd other pplicble regultory limits. 3. Evlute UV oxidtion, with nd without hydrogen peroxide ddition, for tretment of compounds tht re not completely removed by RO membrnes. 4. Evlute operting conditions (specific flux, bckwsh rtes, chemicl clening requirements, nd feed/pressure energy requirements) nd performnce (fouling, recovery rte, nd rejection of trget contminnts) of the AWT membrne processes. 5. Determine the effect of biologicl nitrifiction on system opertions nd product wter qulity. 6. Evlute chemicls/dditives (specificlly chlormines, nti-sclnts, nd cids) necessry for membrne fouling control. 3

24 1.4 TEST LOCATION The study ws conducted t the Districts JWPCP, which is locted in Crson, CA. The JWPCP hs dry wether verge flow design cpcity of 400 million gllons per dy (MGD) of secondry tretment nd pek design cpcity of 540 MGD of secondry tretment. The JWPCP currently trets pproximtely 280 MGD of wstewter. The sources of wstewter re pproximtely 3.5 million residents, commercil businesses, nd over 1,500 permitted industril users. The tretment processes t JWPCP include screening, grit removl, primry sedimenttion, high purity oxygen ctivted sludge, secondry clrifiction, nerobic sludge digestion, nd sludge dewtering. Treted effluent is disinfected prior to dischrge through tunnel nd outfll system to the Pcific Ocen. For this project, test site ws developed from pved loction on the estern side of the JWPCP (Figure 1-1). The site ws selected for its proximity to 12-inch pressurized line crrying unchlorinted JWPCP secondry effluent to the solids processing re of the plnt. The site ws lso selected becuse dringe chnnel is present tht llows project effluent to be dischrged directly into trunk sewer tht flows into the JWPCP. From Mrch to June, 2010, the Districts stff developed the test site by instlling electricl power, nd building or moving on-site vrious structures nd continers to house equipment nd instruments, dt collection devices, chemicls, prts nd tools. A picture of the developed project site is shown in Figure 1-2. Figure 1-1. Pilot Plnt Loction t JWPCP Test Loction 4

25 Figure 1-2. Pilot Plnt Test Are 1.5 PROJECT DURATION AND PHASING Opertion of the pilot-scle system begn in June 2010, nd ended in June The two-yer opertionl period ws divided into three phses, which re summrized in Tble 1-2. For Trin 1, Phse 1 begn fter the UF nd RO units hd reched stedy stte, which ws defined by stble operting prmeters nd wter qulity concentrtions. Becuse more work ws required to modify the MBR for opertion, Phse 1 for Trin 2 begn lter. Phse 1 ended when the RO membrnes on ech trin were removed for utopsy. Phse 2 begn fter deep clen of the RO membrnes on both trins. Phse 2 ended for Trin 1 when the RO unit ws tken out of service to replce the membrnes. Phse 2 ended for Trin 2 when the MBR ws shut down for reconfigurtion. Phse 3 begn fter the MBR reconfigurtion ws complete, the RO membrnes on both trins were replced, nd ll units hd reched stedy stte opertion. Phse 3 ended for Trin 1 when the UF unit ws shut down due to opertionl difficulties. Phse 3 ended for Trin 2 with the end of the project. Tble 1-2. Opertionl Phses Phse 1 Phse 2 Phse 3 Trin 1: UF-RO Strt Dte 7/9/10 7/5/11 1/20/12 End Dte 3/18/11 12/15/11 6/28/12 Trin 2: MBR-RO Strt Dte 12/8/10 7/5/11 1/20/12 End Dte 3/30/11 12/6/11 6/30/12 5

26 1.6 SUMMARY OF LITERATURE REVIEW A literture review on indirect potble reuse (Appendix B) ws prepred by MWD, to summrize key findings regrding the implementtion of indirect potble reuse. The review provided n overview of regultory nd permit requirements for recycled wter in Cliforni. It lso provided cse studies of indirect potble reuse projects in Cliforni, Western Austrli, nd Virgini. The three Cliforni-bsed cse studies were full-scle opertions: the Groundwter Replenishment System in Fountin Vlley, the West Cost Brrier Project in El Segundo, nd the Almitos Brrier Recycled Wter Project in Long Bech. For Western Austrli, the two cse studies were the full-scle Kwinn Wter Reclmtion Plnt nd pilot plnt t the Beenyup Wstewter Tretment Plnt. The lst cse study ws the Millrd H. Robbins, Jr. Wter Reclmtion Plnt in Centreville, Virgini, which dischrged to surfce wters feeding the Occoqun Reservoir. The first five cses were ll indirect potble reuse projects tht treted secondry or tertiry wstewter effluents with combintion of MF, RO, or UV. The Groundwter Replenishment System nd the West Cost Brrier Project lso included hydrogen peroxide with the UV tretment, s n AOP. The Millrd H. Robbins, Jr. Wter Reclmtion Plnt ws designed for nutrient removl to improve the wter qulity of the Occoqun Reservoir; this plnt treted secondry effluent with lime clrifiction, medi filtrtion, crbon contctors, nd chlorine disinfection. Ech cse study covered key permit requirements, tretment processes, wter qulity of the source nd finl product wter, complince with ll Federl nd Stte mximum contminnt levels (MCLs), notifiction levels, nd wter tretment nd disinfection by-products rules, removl of non-regulted compounds, such s phrmceuticls nd personl cre products (PPCPs) nd endocrine disrupting compounds (EDCs), ny specil studies conducted on helth effects or tretment process selection, design, or opertion. All six plnts successfully met their permit requirements; detils re provided in Appendix B. 1.7 REPORT ORGANIZATION The following two chpters provide description of the pilot system (Chpter 2), nd the smpling progrms for the project nd experimentl conditions for the AOP experiments (Chpter 3). The opertionl performnce (e.g., fluxes, fouling, mintennce) of the UF, MBR, nd RO units is discussed in Chpter 4. Wter qulity results re divided into three chpters. Generl wter qulity prmeters re discussed in Chpter 5. Nitrosmines nd 1,4-dioxne re discussed seprtely in Chpter 6, becuse these compounds typiclly drive the AOP requirements for AWT. Chpter 7 provides the results for set of smples referred to s Title 22+ smples, which were tken on six dys nd were nlyzed for more thn 300 prmeters. These smples provided dt for much broder rnge of compounds thn the routine or AOP smples. Finlly, the results nd conclusions for the project re summrize in Chpter 8. 6

27 DESCRIPTION OF PILOT SYSTEM 2.1 OVERVIEW OF PILOT SYSTEM The pilot-scle system consisted of two prllel tretment trins tht treted JWPCP secondry effluent. The secondry effluent ws first sent through three 2-inch Eton-Hywrd striners, operted in prllel. The striners contined stinless steel bskets with 30 mesh (595 micron) liners. Prior to Phse 3 of the project, second set of 40 mesh (400 micron) striners ws instlled upstrem of the UF/RO process trin, to reduce the suspended solids loding. A simplified schemtic digrm of the two tretment trins is shown in Figure 2-1. Trin 1 is referred to s the UF trin throughout this report, nd consisted of Siemens system equipped with ultrfiltrtion (UF) membrnes, followed by reverse osmosis (RO) pilot system. This RO system is referred to s the UF-RO throughout the report. Trin 2 is referred to s the MBR trin throughout this report, nd consisted of modified GE/Zenon membrne biorector (MBR) followed by second RO pilot system, which is referred to s the MBR-RO throughout this report. RO permete generted from ech of the two trins could be further treted by one of two UV AOP systems. The following sections provide more detil on ech of the unit processes: the UF system (Section 2.2), the MBR system (Section 2.3), the RO systems (Section 2.4), nd the two AOP systems (Section 2.5). Figure 2-1. Schemtic Digrm of Tretment Process Trins Chlorine H 2 SO 4 Antisclnt Trin 1 Secondry Effluent Trin 2 UF (Siemens) Filtrte RO #1 Sewer Bckwsh Wter MBR (GE/Zenon) Ammoni Chlorine Permete Sewer H 2 SO 4 Antisclnt RO #2 Permete Concentrte Permete Hydrogen Peroxide Trojn LP UV Hydrogen Peroxide Clgon Btch LP/MP UV Sewer Sewer Sewer Concentrte 2.2 SIEMENS MEMBRANE FILTRATION (UF) UNIT For this project, MWD provided Siemens 12M10C continuous filtrtion unit (Figure 2-2), which could tret up to 60 gllons per minute (gpm) of flow. This pressurized membrne filtrtion unit utilized hollow-fiber membrnes to provide removl of suspended solids, prticles, colloids, nd bcteri. The unit ws originlly outfitted with polypropylene (PP) MF membrnes with nominl pore size of 0.2 micron. These membrnes re in common use t severl locl wter reuse projects, including fcilities t Ornge County Wter District (OCWD), West Bsin Municipl Wter District (WBMWD) nd the Terminl Islnd Wter Reclmtion Plnt 7

28 (TIWRP). However, for this project, the unit ws upgrded to L10V polyvinylidene fluoride (PVDF) UF membrnes, which offered the dvntge of more durble membrne mteril, with greter chlorine resistnce, nd the bility to use strong solutions of sodium hypochlorite s routine clening chemicl. The chrcteristics of the PVDF membrnes re given in Tble 2-1. Figure 2-2. Siemens 12M10C Continuous Membrne Filtrtion Unit Tble 2-1. Siemens PVDF UF Membrnes Prmeter Units Vlue Sub-module Type - L10V Membrne Mteril - PVDF Membrne Type - Hollow fiber Filtrtion Direction - Outside to inside Pore Size (nominl) micron 0.04 No. of Fibers per Element - 9,600 Ave. Active Membrne Are (OD) ft Operting Temperture Rnge o C >0-40 Mximum Temperture o C 45 Operting ph Rnge Mx. Trns-Membrne Pressure (TMP) psi 22 Mx. Exposure to Chlorine/Chlormine ppm 1,000 A progrmmble logic controller (PLC) ws used for the UF nd provided utomtic control of the pneumtic system, which controlled the ir supply, regulted ir pressure for the bckwsh nd re-wetting cycles, nd provided proper pressure for operting the membrne integrity tests. The PLC rn n ir pulse bckwsh regime tht llowed continuous opertion of the unit, nd lso monitored the operting sttus of the unit. Operting prmeters from the system were monitored, displyed continuously, nd stored in dt logging system. Recorded dt included 8

29 feed nd filtrte pressure, trnsmembrne pressure (TMP), flow resistnce, feed flow, feed pump speed, feed temperture nd ph, filtrte flow, flow totls, filtrte runtime, pressure decy from integrity tests, bckwsh intervls, pneumtic system/ir compressor sttus, feed vlve positions, feed tnk fill nd drwdown times, nd other pertinent observtions. In ddition, totl chlorine residul concentrtions were mesured nd the dt recorded with hypochlorite delivery rte. The unit ws checked nd key dt mnully recorded twice dy during weekdys nd t lest once ech weekend. The PLC ws locted on the min skid, long with the influent tnk, feed pump, nd filtrtion modules. In ddition to the min skid, the pilot system included 500-gllon bckwsh tnk nd n ir compressor/receiver. Clen-in-plce (CIP) procedures used n externl CIP skid with heted 100-gllon tnk tht ws built for RO system clenings. UF filtrte ws stored in n 800- gllon brek tnk, which stbilized chlorine residul levels in the influent to the RO system; otherwise, residuls would hve fluctuted during production interruptions, e.g., when the membrnes were bckwshed. 2.3 GE/ZENON MBR UNIT Overview A schemtic of GE/Zenon MBR pilot system used in this project is shown in Figure 2-3. Secondry effluent from the JWPCP ws pumped into n ertion tnk where it ws mixed with the recycled mixed liquor from the membrne tnk nd erted. The contents of the ertion tnk were pumped to the membrne tnk, nd self-priming centrifugl pump drew permete through the membrnes. A smll portion of the mixed liquor in the membrne tnk ws continuously wsted, to control the solids retention time (SRT) of the system. Figure 2-3. Schemtic Digrm of GE/Zenon MBR Pilot Plnt Mixed Liquor Recycle Secondry Effluent Aertion Tnk Membrne Tnk Permete Sludge Wsting Pictures of the MBR system re shown in Figure 2-4. Figure 2-4 shows the system s it ws configured in Phses 1 nd 2. The cylindricl ertion tnk (pinted beige) cn be seen on the left side of the picture. The rectngulr stinless steel membrne tnk cn be seen in the middle of the picture, long with the overflow chnnel connecting the membrne nd ertion tnks; mixed liquor ws recycled bck to the ertion tnk by grvity overflow through this chnnel. Two interconnected cylindricl tnks for permete storge cn be seen on the right side of Figure 2-4. Figure 2-4b shows the membrne tnk nd overflow chnnel used in Phse 3, fter modifictions tht re described in Section The following sections describe the mjor components of the MBR system: the ertion tnk (Section 2.3.1), the membrne tnk (Section 2.3.2), nd the permete tnks (Section 2.3.3). 9

30 Figure 2-4. GE/Zenon Membrne Biologicl Rector. () Phses 1 nd 2, (b) Modified Membrne Tnk in Phse 3. () (b) Aertion Tnk The MBR system for this project ws previously used to tret primry effluent, similr to most MBR systems; however, for this project, the MBR ws used to nitrify secondry effluent. The 6,700-gllon (gl) ertion tnk tht ws originlly supplied with the system ws fr lrger thn needed for nitrifiction. Therefore, the originl ertion tnk ws replced with 800-gl polyethylene cylindricl tnk before Phse 1. The decrese in size reduced the hydrulic residence time (HRT) nd energy consumption. The ertion tnk ws equipped with corse bubble diffuser (mximum ir flow rte of 5 stndrd cubic feet per minute, or scfm) for mixing nd fine bubble diffuser (mximum ir flow rte of 28 scfm) for ertion. The tnk ws pinted to reduce exposure of the mixed liquor to sunlight, which would promote lge growth Membrne Tnk The membrne tnk supplied with the system hd working volume of 1,588 gl, nd ws used for Phses 1 nd 2. The membrne tnk ws modified for Phse 3. To chieve the desired flux (see Section for detils), new membrnes were required, nd these membrnes were tller thn the previous modules. Consequently, the membrne tnk ws mde deeper by the ddition of n eighteen-inch collr extension, nd the overflow flume ws modified to ccommodte higher overflow elevtion. The modifictions for Phse 3 incresed the working volume of the tnk to 2,075 gllons. Detils on the membrnes nd modules within the membrne tnk re provided in Tbles 2-2 nd 2-3. The membrne tnk originlly contined two cssettes, which were pproximtely eight yers old t the time the project begn; they were previously used to tret primry effluent t nother plnt operted by the Districts. Ech cssette contined ten ZeeWeed 500c modules; the two cssettes (lso referred to s pcks ) were designted s the north nd south pcks. Phse 1 used both cssettes, but Phse 2 used only one of the cssettes, to increse the operting flux; the cssette in service ws lternted between the north nd south pck. Phse 3 used single cssette contining eight new ZeeWeed 500d modules; the 500d membrnes re less prone to fouling nd offer more cpcity thn the 500c membrnes. This cssette replced one of the two pcks previously in the membrne tnk; the other pck ws replced by n uxiliry ir diffuser, which provided both ertion nd mixing. 10

31 Tble 2-2. GE/Zenon ZeeWeed Membrnes Prmeter Unit Phses 1 nd 2 Phse 3 Membrne Nme - ZeeWeed 500c ZeeWeed 500d Membrne Mteril - PVDF PVDF Membrne Type - Hollow fiber Hollow fiber Filtrtion Direction - Outside to inside Outside to inside Pore Size (nominl) micron Operting Temperture Rnge o C Mximum Temperture o C 54* 40 Operting ph Rnge Mx. TMP psi 10* 8 Mx. Chlorine Concentrtion ppm 2,000* 1,000 *Bsed on converstions with the mnufcturer. Tble 2-3. MBR Membrne Configurtion Prmeter Units Phse 1 Phse 2 Phse 3 Membrne Tnk Volume gl 1,588 1,588 2,075 Modules Module Height ft Module Width ft Module Length ft Cssettes Number of Cssettes in Service Number of Modules/Cssette Totl Number of Modules Totl Active Membrne Are ft 2 4,730 2,365 2, Permete Tnks The permete generted from the membrne tnk ws stored in two 800-gl permete tnks (Figure 2-4), which were interconnected so tht wter could flow freely between the two tnks. The tnks were pinted to reduce exposure of the permete to sunlight, which would promote lge growth. MBR permete from the tnks ws used to feed the RO pilot system nd ws lso used during membrne bckpulse procedures nd mintennce clening opertions (see Section for detils on bckpulses nd clenings). 11

32 2.4 REVERSE OSMOSIS (RO) PILOT SYSTEM The RO system ws the second step of tretment in both the UF nd MBR trins (see Figure 2-1); the two RO systems were identicl. Ech consisted of chemicl metering pumps for cid nd nti-sclnt ddition, 5-μm crtridge filter, high-pressure pump, nd two-stge pressure vessel rry. The pressure vessels were configured in 2:2:1:1 rry, contining totl of 21 spirl wound membrne elements (4-inch dimeter, 40-inch length). The configurtion is shown in Figure 2-5. Stge 1 vessels contined 14 elements (two prllel series of seven elements) while Stge 2 vessels contined seven elements in series. Hydrnutics ESPA2 membrne elements were used in ll three opertionl phses; new set of membrnes ws instlled on ech RO unit between Phses 2 nd 3. A photogrph of the RO unit is shown in Figure 2-6, nd design specifictions of the RO units re listed in Tble 2-4. Figure 2-5. RO Pilot System Configurtion Acid & Antisclnt Addition Stge 1 Pressure Vessels 4 elements 3 elements Stge 2 Pressure Vessels Feed Crtridge Filters High Pressure Pump 4 elements 3 elements 4 elements 3 elements Concentrte Permete Figure 2-6. RO Pilot Unit 12

33 Tble 2-4. RO Pilot System Prmeter Membrnes nd Housing RO membrnes Filter Housing Mximum Pressure Prefilter Power RO Skid Pump Instrumenttion nd Controls RO Control System Instrumenttion Liquid Filled Pressure Gges Antisclnt System Chemicl Addition Tnks Chemicl Addition Pumps Description 4-inch dimeter Hydrnutics ESPA2 Bekert PROTECT TM Model PRO SP 300 psig 5 micron crtridge 480V/3 phses/60hz 7.5 hp R&D Specilties Series 250 PLC controller with communiction pckge, sttus lmps nd pump motor stter Influent flow, permete nd concentrte flow meters, conductivity sensors, ph meter nd pressure sensors Pnel mount for pump effluent, membrne feed nd finl concentrte Two 25-gllon tnks Two Pulsfeeder chemicl pumps Opertion ws controlled by pre-progrmmed control system specificlly designed for the RO unit. The RO system ws equipped with high-pressure pump nd flow control vlves to mnully control permete nd concentrte flow rtes, nd vlves to llow smpling of the RO feed (fter chemicl ddition), permete, nd concentrte. The RO unit ws lso equipped with instrumenttion to electroniclly monitor nd record key process dt in loggers: flow, pressure, conductivity, ph, nd temperture dt t key loctions throughout the RO process. In ddition to the utomticlly logged dt, dt were mnully recorded in the event tht the internlly stored dt becme corrupt or lost. 2.5 ADVANCED OXIDATION PROCESS (AOP) For the dvnced oxidtion process (AOP) in this study, hydrogen peroxide ws dded to RO permete nd followed by UV oxidtion. Two different UV systems were used in this project: set of three flow-through Trojn UV Mx G rectors (Trojn Technologies, London, Ontrio) operted in prllel, nd btch Clgon Ryox rector (Clgon Crbon Corportion, Pittsburgh, PA). Section provides more detils on the Trojn rectors, nd Section provides more detils on the Clgon rector. It should be noted tht UV doses re highly specific for ech rector design (e.g., rector configurtion nd hydrulics); dose determined for this rector system cnnot be pplied to nother system. Results from this system re intended to demonstrte the level of tretment tht cn be chieved with this technology, nd cnnot be used to design full-scle system. 13

34 2.5.1 Trojn UV Mx G Rectors Most experiments used the Trojn system. A schemtic digrm of the system is shown in Figure 2-7 nd photo is shown in Figure 2-8. Ech of the three UV rectors ws equipped with single low-pressure high-output (LPHO) 100-W mlgm lmp tht emitted monochromtic rdition t wvelength of 254 nm. The AOP system could be fed with either UF/RO permete or MBR/RO permete. Adjustble-flow peristltic pumps were used to spike this influent strem with NDMA nd/or 1,4-dioxne, nd were lso used to dd hydrogen peroxide. Sttic mixers were used to quickly mix in these compounds with the RO permete. The wter ws then directed through the UV rectors; UV dose ws determined by setting the flow rte through the rector(s). Figure 2-7. Schemtic Digrm of Trojn AOP System Bleed Influent from MBR/RO 1,4-dioxne NDMA H 2 O 2 Dosing Point F F Trojn UV Unit #1 Effluent F F F F Trojn UV Unit #2 Effluent Influent from UF/RO F Trojn UV Unit #3 Effluent Legend F Flow Controller On-Off Vlve Sttic Mixer 14

35 Figure 2-8. Trojn AOP System Clgon Ryox UV Rector Figure 2-9 shows the Clgon Ryox unit, with the control pnel on the left nd the 11-gl rector on the right. This system becme vilble during Phse 3, nd ws used only for Title 22+ testing in this phse (see Section 3.4). The rector could be configured with either LPHO or medium pressure (MP) lmp. The LPHO lmp ws 40-W lmp tht emitted monochromtic rdition t wvelength of 254 nm. The MP lmp ws 1-kW lmp tht emitted polychromtic rdition. Figure 2-9. Clgon AOP System 15

36 As with the Trojn system, the Clgon rector could be filled with either UF/RO permete or MBR/RO permete. Before ech test, the rector ws filled nd emptied twice with the test wter to flush out the system. NDMA, 1,4-dioxne, nd/or hydrogen peroxide could be spiked into the rector through port t the top. Wter in the rector ws mixed by propeller, nd pneumticlly controlled shutter ws used to set the UV dose, i.e., the durtion of exposure to UV rdition. The shutter could be opened nd closed mnully, or utomticlly on timer. Het from the medium pressure lmp could be removed nd wter temperture could be controlled by pumping wter from n ice bth through cooling coils in the rector. Smples were tken from either smpling port on the side of the rector, or from the bottom drin; both sites were flushed before smples were tken. 16

37 3. WATER QUALITY SAMPLING PROGRAM AND TARGETS This chpter discusses the wter qulity smpling progrm for this project, nd the wter qulity trgets. Section 3.1 describes the smpling loctions. The other sections in this chpter describe different smpling progrms t these loctions. Section 3.2 covers routine smples tht were tken for 26 prmeters on dily, weekly, or bi-weekly bsis. Section 3.3 covers smples tken for 1,4-dioxne nd nitrosmine nlysis, nd smples tken during the AOP experiments. Section 3.4 covers n extensive list of lmost 300 prmeters (referred to s the Title 22+ prmeters) tht were nlyzed during six specil smpling events. Section 3.5 covers wter qulity trgets for the nlyzed compounds. The nlyticl methods for ll prmeters re provided in Appendix C. 3.1 SAMPLING LOCATIONS Figure 3-1 shows schemtic of the pilot-scle system with the smpling loctions lbeled. Smples were tken from the secondry effluent (Loction 1), nd t three loctions on the UF trin: UF filtrte (Loction 2), UF-RO permete (Loction 3), nd UF-RO concentrte (Loction 4). Smples were lso tken t three loctions on the MBR trin: MBR permete (Loction 5), MBR-RO permete (Loction 6), nd MBR-RO concentrte (Loction 7). Loctions 8-13 were on the UV rectors. Loctions 8-12 were for the three Trojn UV rectors, which re described in Section Loction 8 provided the influent smples for the UV rectors, nd ws downstrem of the dditions points for NDMA nd 1,4-dioxne. Loction 9 ws locted downstrem of the hydrogen peroxide ddition point, nd provided smples treted by hydrogen peroxide lone. Loctions were locted downstrem of ech of the three UV rectors, nd provided smples treted by UV lone or the combintion of UV nd hydrogen peroxide. Loction 13 ws on the Clgon Ryox btch rector, which is described in Section Smples from Loction 13 were tken t different time points to provide concentrtion dt for the influent smples nd effluent smples (fter vrying doses of hydrogen peroxide nd/or UV rdition). Figure 3-1. Schemtic Digrm of Smpling Loctions Trin 1 1 Secondry Effluent Chlorine UF 2 3 (Siemens) RO #1 Filtrte Permete Bckwsh 4 Wter Concentrte Sewer Ammoni Chlorine H 2 SO 4 Antisclnt Sewer H 2 SO 4 Antisclnt Hydrogen Peroxide 8 9 Trojn LP UV Hydrogen Peroxide Sewer Trin 2 MBR (GE/Zenon) 5 6 RO #2 Permete Permete 7 Clgon LP/MP UV 13 Sewer Sewer Concentrte 17

38 3.2 ROUTINE ANALYSIS The loctions nd frequency of the routine smples re listed in Tble 3-1. Most nlytes were smpled bi-weekly in the secondry effluent, UF filtrte, UF-RO permete, MBR permete, nd MBR-RO permete (Loctions 1, 2, 3, 5, nd 6). To monitor the unit processes on finer time scle, severl prmeters were smpled dily or weekly: turbidity, ph, the nitrogen species (mmoni, totl Kjeldhl nitrogen, nitrte, nitrite), totl orgnic crbon (TOC), totl nd soluble chemicl oxygen demnd (COD), nd totl suspended solids (TSS). The concentrte strems from the UF-RO nd MBR-RO systems were smpled nd nlyzed qurterly. Some nlytes were eliminted t selected loctions. For exmple, becuse prticles were expected to be lrgely removed by the UF or MBR membrnes, turbidity nd TSS were not fter these units. Soluble COD ws expected to be identicl to totl COD in the MBR permete due to the removl of TSS, consequently it ws not mesured. Tble 3-1. Wter Qulity Prmeters: Smpling Frequency Smpling Loctions UF Trin MBR Trin Prmeters ph D D W Q D W Q Turbidity D D D Alklinity BW BW BW Q BW BW Q Clcium BW BW BW Q BW BW Q Mgnesium BW BW BW Q BW BW Q Sodium BW BW BW Q BW BW Q Potssium BW BW BW Q BW BW Q Sulfte BW BW BW Q BW BW Q Chloride BW BW BW Q BW BW Q TDS BW BW BW Q BW BW Q TSS D COD (Totl) D Q D -- Q Soluble COD (scod) D TOC W W W Q W W Q Ammoni D W W Q D W Q Nitrte W W W Q D W Q Nitrite W W W Q D W Q TKN D W W Q W W Q Phosphte BW BW BW Q BW BW Q Boron BW BW BW Q BW BW Q Silic BW BW BW Q BW BW Q Brium BW BW BW Q BW BW Q Strontium BW BW BW Q BW BW Q Fluoride BW BW BW Q BW BW Q Iron BW BW BW Q BW BW Q Aluminum BW BW BW Q BW BW Q Frequency bbrevitions: D Dily, W- Weekly, BW Bi-weekly, Q - Qurterly 18

39 3.3 NITROSAMINES, 1,4-DIOXANE, AND AOP TESTING This section discusses smpling for nitrosmines nd 1,4-dioxne, nd the AOP experiments. Seven nitrosmine species were nlyzed: N-nitrosodimethylmine (NDMA), N- nitrosodiethylmine (NDEA), N-nitrosodipropylmine (NDPA), N-nitrosodibuylmine (NDBA), N-nitrosomethylethlymine (NMEA), N-nitrosopiperidine (NDPA), nd N-nitrosopyrrolidine (NPYR). The nitrosmines nd 1,4-dioxne were nlyzed in bi-weekly smples tken from the secondry effluent, MBR permete, nd both RO permetes. Becuse these compounds typiclly determine the AOP requirements for AWT systems, much of the smpling ws focused on the AOP experiments. The AOP system ws not operted continuously; insted, discrete experiments were conducted to determine the effects of UV electricl energy doses (EEDs) nd hydrogen peroxide doses on the removl of nitrosmines nd 1,4-dioxne. Literture indictes tht UV rdition removes NDMA, hydrogen peroxide hs insignificnt effect on NDMA, nd both UV nd hydrogen peroxide re necessry to remove 1,4- dioxne. Bsed on this informtion, experiments were split into three bsic tsks: to determine the pproximte UV dose required for dequte NDMA removl, to determine the pproximte hydrogen peroxide dose required for dequte removl of 1,4-dioxne, nd to investigte the effects of combining UV nd peroxide. These three tsks were run on both the UF nd MBR trins (six tsks totl). Most tsks were run twice, except for Tsk 6 (which hd some nlyticl issues nd ws run three times), for totl of 13 AOP experiments. Experiments were conducted during Phse 1, nd the results of ll 13 experiments were combined for the nlysis (Chpter 6). Tble 3-2 summrizes the AOP tsks, with the UV electricl energy doses (EEDs) nd peroxide doses. EEDs were clculted using the following eqution: EED, kwh/kgl UV Power, kw Flow Rte (gpm) 1,000 gl kgl 1hr 60 min It should be noted tht the EED vlues used in this study re specific to these UV rectors, nd their rector geometry nd flow hydrulics. Therefore, these EED vlues cnnot be scled up or pplied to other UV systems. Tble 3-2. Summry of AOP Experiments. Experiment Tested UV Tested H Gol: 2 O 2 Number EEDs Doses UF/RO MBR/RO Determintion of kwh/kgl mg/l 1 2 Approximte UV dose Approximte H 2 O 2 dose ~ Effects of Combined UV/H 2 O Although the AOP experiments focused on the nitrosmines nd 1,4-dioxne, other wter qulity prmeters were nlyzed in selected smples: mmoni, totl Kjeldhl nitrogen (TKN), nitrite, nitrte, totl orgnic crbon (TOC), chemicl oxygen demnd (COD), UV trnsmittnce (UVT), ph, nd temperture. The effects of AOP on these prmeters re discussed in Chpter 5. 19

40 3.4 TITLE 22+ SAMPLING For the Title 22+ smpling events, 299 prmeters were nlyzed. There re EPA or CDPH drinking wter stndrds for most of these prmeters, or monitoring ws required by the CDPH DGRR (e.g., for Priority Toxic Pollutnts), lthough commonly studied trce orgnic constituents such s phrmceuticls were lso mesured. The prmeters included ll of the compounds listed in Tble 3-1, the seven nitrosmine species, 1,4-dioxne, rdioctive nlytes, UV trnsmittnce, microbiologicl prmeters, voltile nd semi-voltile orgnic compounds, pesticides, herbicides, disinfection byproducts, hormones, nd phrmceuticl nd personl cre products. Appendix C provides full list of the compounds, the nlyticl methods used to quntify them, nd their reporting limits. Smples were collected on two dys ech from the UF trin during Phse 1, the MBR trin during Phse 1, nd the MBR trin during Phse 3. The verge UF flux ws pproximtely 22 gfd throughout the study (see Section for detils). During Phse 1, smples were collected from the secondry effluent, UF filtrte, UF-RO permete, nd the AOP effluent on Februry 16, Smples were lso collected t the first three loctions (ll except the AOP effluent) on Februry 23, AOP testing used the Trojn UV Mx G rector (described in Section 2.5.1), with rector-specific EED of 4 kwh/kgl, nd hydrogen peroxide dose of 4 mg/l. The verge MBR flux during Phse 1 ws 10 gfd, pproximtely hlf tht of the UF. Smples were collected from the secondry effluent, MBR permete, MBR-RO permete, nd AOP effluent on Mrch 2, Smples were lso collected t the first three loctions (ll except the AOP effluent) on Mrch 9, AOP testing used the Trojn UV Mx G rector, with rector-specific EED of 4 kwh/kgl, nd hydrogen peroxide dose of 4 mg/l. The verge MBR flux during Phse 3 ws 20 gfd, similr to tht of the UF. Smples were collected on My 15 nd 22, 2012, from the secondry effluent, MBR permete, MBR-RO permete, nd AOP effluent. AOP testing used the Clgon Ryox btch rector (described in Section 2.5.2), nd both low pressure (LP) nd medium pressure (MP) lmps were tested. The rector-specific EED ws 0.9 kwh/kgl for the LP lmps nd 1.5 kwh/kgl for the MP lmps. The hydrogen peroxide dose ws 4 mg/l for ll tests with the Clgon rector. Note tht the lbortory chnged the hormone nlysis method between Phses 1 nd 3, so the hormones mesured on these smpling dtes were slightly different from the other dtes: progesterone ws not nlyzed, but estriol, equilin, testosterone nd ndrostenedione were nlyzed. 3.5 WATER QUALITY TARGETS Trgets for wter qulity were bsed on requirements for groundwter rechrge, nd were set to the lowest of the following vlues for ech prmeter: EPA primry mximium contminnt levels (MCLs) nd secondry MCLs for drinking wter, CDPH primry nd secondry MCLs, nd notifiction levels (NLs) for drinking wter, CDPH DGRR levels for totl nitrogen, TOC, nd turbidity, locl bsin pln objectives for Western Sub-bsin of the Min Sn Gbriel Bsin, SWRCB monitoring trigger levels for chemicls of emerging concern (note tht these levels re guidelines, not regultory requirements). 20

41 In ddition to these limits, removl requirements for N-nitrosodimethylmine (NDMA) nd 1,4- dioxne from the 2008 CDPH DGRR were pplied to the AOP portion of the study; the 2011 DGRR (relesed prtwy through this project) eliminted the NDMA requirement, but it ws kept for this project. Tbles 3-3 nd 3-4 list the trget concentrtions for nlytes detected in this study. A full list of the compounds nlyzed, the vrious limits (e.g., MCLs), nd the trget concentrtions cn be found in Appendix C. Tble 3-3. Trget Effluent Concentrtions for Generl Physicl nd Minerl Prmeters, Trce Metls, nd Rdiologicl Anlytes Trget Ctegory Constituent Conc. Units Generl Chloride 100 mg/l Physicl Color 15 ACU nd Conductivity 1,600 umho/cm Minerl Fluoride 2 mg/l Prmeters Foming Agents (MBAS) 1 mg/l Nitrte 10 mg N/L Nitrite 1 mg N/L Odor 3 TON ph Sulfte 100 mg/l TDS 450 mg/l Totl Nitrte + Nitrite 10 mg N/L Totl Nitrogen 10 mg N/L Totl Orgnic Crbon 0.5 mg/l Turbidity 2 NTU Trce Aluminum 50 g/l Metls Antimony 6 g/l Arsenic 10 g/l Brium 1,000 g/l Boron 0.5 mg/l Chromium (Totl) 50 g/l Copper 1300 g/l Iron 0.3 mg/l Led 15 g/l Mngnese 50 g/l Nickel 100 g/l Selenium 50 g/l Rdiologicl Gross Bet 50 pci/l Urnium 20 pci/l 21

42 Tble 3-4. Trget Effluent Concentrtions for Other Prmeters Trget Ctegory Constituent Conc. Units 1,4-Dioxne 1,4-Dioxne 1 1 g/l nd N-Nitrosodimethylmine (NDMA) 2 10 ng/l Nitrosmines N-Nitrosodiethylmine (NDEA) 10 ng/l N-Nitrosodi-n-propylmine (NDPA) 10 ng/l N-Nitrosopyrrolidine (NPYR) 20 ng/l Hormones 17 -estrdiol 1 ng/l nd Bisphenol A 350,000 ng/l EDCs Nonylphenol 500,000 ng/l Octylphenol 50,000 ng/l PPCPs Acetminophen 350,000 ng/l nd Azithromycin 3,900 ng/l Wstewter Crbmzepine 1,000 ng/l Indictors Gemfibrozil 45,000 ng/l Ibuprofen 34,000 ng/l Meprobmte 260,000 ng/l Sulfmethoxzole 35,000 ng/l Triclosn 350 ng/l DEET 2,500 ng/l Cffeine 350 ng/l Iopromide 750,000 ng/l TCEP 2,500 ng/l VOCs 3 Dichloromethne 5 g/l MTBE 5 g/l Totl THMs 80 g/l SVOCs 3 Di (2-Ethylhexyl) Phthlte 4 g/l Pesticides 3-hydroxycrbofurn 0.42 g/l Other Formldehyde 100 g/l Tertiry Butyl Alcohol 12 g/l Crbon disulfide 160 g/l Chlorte 800 g/l 1 1,4-dioxne hd n dditionl tretment requirement of 0.5-log removl in both the 2008 nd 2011 DGRRs. 2 NDMA hd n dditionl tretment requirement of 1.2-log removl in the 2008 DGRR; this requirement ws removed in the 2011 drft, but ws kept s trget for this project. 3 VOCs refer to voltile orgnic compounds, nd SVOCs refer to semi-voltile orgnic compounds. 22

43 4. SYSTEM OPERATION This chpter discusses the opertion of the two dvnced tretment process trins, including dt collected nd mintennce performed. The UF tretment trin is presented in Section 4.1, nd includes the UF unit (Section 4.1.1) nd the UF-RO system (Section 4.1.2). The MBR tretment trin is presented in Section 4.2, nd includes the MBR unit (Section 4.2.1), nd the MBR-RO system (Section 4.2.2). 4.1 UF TREATMENT TRAIN UF Opertion The components of the membrne filtrtion system were received from MWD in mid-april New UF membrnes were purchsed nd instlled in erly June A strong sodium hypochlorite solution (1,000 ppm) ws circulted through the unit prior to the instlltion of new UF membrne elements to ensure tht ll connecting heders, piping nd vessels were free of lge. The UF unit ws operted from June 25, 2010 to June 28, 2012, nd treted totl flow of more thn 40 million gllons; note tht these dtes (nd the totl flow vlue) reflect the totl opertionl time, including time before the UF nd RO systems cme to stedy stte, nd the time between phses. The unit ws in productive opertion (producing filtrte) for 13,700 hours over 726 dys of testing. For the durtion of the study, the UF ws ble to successfully produce more filtrte thn ws required for RO opertions, despite some opertionl difficulties (described in Sections nd ). Opertion of the UF ws occsionlly interrupted by power or flow outges, membrne clenings, nd mintennce. Some of the downtime ws unplnned, cused by filures of the project feed piping t the mnifold upstrem nd downstrem of the bsket striners. The filures typiclly occurred in three-inch PVC fittings. To correct the problem, severl wter hmmer rrestors nd pressure regultor were instlled to llevite stress from vlve cycling, nd PVC fittings nd piping in the striner mnifold were replced with steel components UF System Operting Prmeters The recommended operting prmeters for the UF unit re summrized in Tble 4-1, long with the ctul rnge of operting vlues for the entire test period; description of the clening procedures is given in Section The UF unit ws operted t constnt flux of pproximtely 22 gfd, which required feed flow rte of 46 gpm. The flux nd flow rte were mintined throughout most of the study. Throughout the study, the totl chlorine residul of the UF filtrte ws mintined t n verge of 3.4 mg Cl 2 /L (within the trget rnge of mg Cl 2 /L); pproximtely 6-10 mg Cl 2 /L (n verge of 8.4 mg/l) of sodium hypochlorite (NOCl) ws dded to the secondry effluent to chieve the trget residul. 23

44 Tble 4-1. UF System: Flows, Fluxes, nd Mintennce Prmeter Units Recommended Vlue Actul Vlue Flows Feed gpm Wste/Bckwsh* gpm Net Filtrte/Permete gpm Flux nd Recovery Flux gfd Recovery (for L10V Module) % Bckwsh Frequency min Flow gpm Co-current Durtion sec Counter Current Durtion sec Chemiclly Enhnced Bckwsh (CEB) Frequency dys NOCl Concentrtion mg/l Sok Durtion min Rinse Durtion sec Clen in Plce (CIP) Frequency dys Citric Acid Concentrtion** % 2 2 NOCl Concentrtion mg/l Durtion hrs 6 6 * Equivlent continuous flow rte ** Citric cid solutions were heted to 100 F (38 C), per the mnufcturer s recommendtion UF System Performnce Dt Opertion of the UF system ws evluted bsed on clening frequency nd other key prmeters: feed nd filtrte pressure, TMP, permebility, flux, nd membrne integrity. Operting prmeters re discussed in this section, nd clening requirements re discussed in the Section Flow, flux, nd pressure dt in this section were dily verges clculted from the 5- min dt collected utomticlly by the system loggers. Dt tken during opertionl interruptions (e.g., bckwshes) were excluded from the clcultion of the dily verge vlues. Tble 4-2 presents the verge, minimum, nd mximum vlues for relevnt operting prmeters from the mnully recorded dt, for the three opertionl phses in this study (Section 1.5). Although temperture dt re not included in this section, sensitivity nlysis indicted tht temperture ws unlikely to hve strong impct on the UF performnce. Membrne Integrity Membrne integrity ws mesured dily through pressure decy test; high vlues cn indicte dmge to the membrne fibers. Results re plotted in Figure 4-1. The high nd low decy rte spikes re relted to unusul membrne pressure conditions relted to clening events (discussed in detil in the next section). All tests were successful; the decy rte ws lwys < 1.5 psi/min, which ws defined by the mnufcturer s the mximum cceptble vlue for drinking wter tretment, nd showed no signs of membrne dmge. 24

45 Tble 4-2. Selected UF System Operting Dt by Phse 25 Phse 1 Phse 2 Phse 3 Monitored Prmeter Units Ave Min Mx Ave Min Mx Ave Min Mx Operting Times Dys of Opertion dys Totl Filtrte Run Time hours 5, , , Flows nd Relted Prmeters Totl Flow Processed MG Feed Flow gpm Flow Set Point gpm Filtrte Flow gpm Pressures nd Relted Prmeters Feed Pressure psi Filtrte Pressure psi TMP psi Flow Resistnce Pressure Decy psi/min Other Prmeters Set Point, Time Between Bckwsh min NOCl Delivery Rte ml/min Totl Chlorine Residul mg/l

46 Pressure Decy Test Result (psi/min) Figure 4-1. UF System Membrne Integrity Phse 1 Phse 2 Phse 3 - Interim periods Dte Feed Pressure, Filtrte Pressure, nd TMP Feed nd filtrte pressure dt for the UF system re shown in Figure 4-2, nd TMP vlues re shown in Figure 4-3; the TMP is simply the difference between the feed nd filtrte pressures. The filtrte pressure ws mintined just over 10 psi, nd feed pressures typiclly peked between 25 nd 30 psi. TMP vlues typiclly peked round 17 psi, t which point the membrnes were clened. The feed pressures nd TMPs decresed following clening (see Section for detils on the clenings) becuse less pressure ws required to mintin the trget flux. During Phses 1 nd 2, minimum feed pressures were roughly 15 psi nd minimum TMP vlues were generlly < 5 psi. These vlues incresed during the winter, but decresed gin in the spring. This trend ws likely due to incresed fouling cused by decline in wter qulity tht ws observed during the winter, followed by incresed clening nd improved vlues in the spring (see Section for detils on fouling nd clenings). During Phse 3, the feed pressure incresed to > 25 psi, nd the TMP incresed to > 15 psi. Figure 4-2. UF System Feed nd Filtrte Pressure Pressure (psi) Phse 1 Phse 2 Phse 3 Feed Filtrte - Interim periods Dte 26

47 Figure 4-3. UF System TMP 20 Phse 1 Phse 2 Phse 3 TMP (psi) Interim periods Dte Flux nd Permebility Membrne flux is plotted in Figure 4-4; the UF system ws operted t trget flux of 22 gfd. Figure 4-5 shows the observed permebility, s well s temperture-corrected vlues, which were clculted from equtions provided by the mnufcturer. Both prmeters declined over time, prticulrly during Phse 3. The flux declined to slightly below the trget flux of 22 gfd over the course of the two yers of opertion, nd declined more quickly during the finl months of Phse 3 opertion. For membrne permebility, temperture did not hve strong effect, s shown by the comprison of the two series plotted in Figure 4-5. Permebility incresed ech time the membrnes were clened, but the mximum vlue fter clening declined over time nd could not be restored to bove the lower cceptble minimum (2 gfd/psi) by the middle of Phse 3. Figure 4-4. UF System Membrne Flux 23 Phse 1 Phse 2 Phse 3 Flux (gfd) Interim periods Dte 27

48 Figure 4-5. UF System Membrne Permebility Permebility (gfd/psi) Phse 1 Phse 2 Phse 3 - Interim Periods Dte Although the cuse of the poorer performnce in Phse 3 ws not definitively identified, decline in wter qulity likely contributed to the increse in fouling. Concentrtions of severl constituents in the secondry effluent incresed significntly between Phses 2 nd 3: TSS, turbidity, TOC, COD, mmoni nd TKN, lklinity, nd potssium (Chpter 5). Despite the fouling issues, the UF unit continued to produce consistent, high-qulity filtrte, with verge turbidity vlues in the product filtrte ctully decresing slightly through the study Clening of the UF System Description of Clenings Four types of clenings were conducted during this study. The chemiclly enhnced bckwshes (CEBs) nd clen-in-plce (CIPs) were regulrly scheduled; detils on the clening solutions re listed in Tble 4-1. The CEB procedure ws single bckwsh with 500-1,000 mg/l sodium hypochlorite solution, followed by min sok. This procedure ws improved t the beginning of Phse 3 by replcing the single bckwsh with series of 2-3 bckwshes with soks. The totl CEB run time remined the sme (~30 min), but the resulting TMP vlues were lower. The CIP consisted of recirculting nd soking the membrnes in two seprte solutions: one ws 2% citric cid nd the other ws 500-1,000 mg/l sodium hypochlorite. The totl durtion of ech CIP ws pproximtely 6 hours. In ddition to the regulrly scheduled CEBs nd CIPs, two other types of clenings were conducted s time llowed, e.g., during shutdowns. The extended clenings (ECs) were similr to the CEBs, but lso included % Micro-90 surfctnt. Recircultion ws extended nd the membrnes were soked overnight; the totl durtion of ech EC ws 3-5 dys. The second type of clening ws the hypochlorite sok, which ws similr to the CIP, but recircultion nd sok times were extended, with soks often conducted overnight. A summry of clening intervls, unit vilbility nd recovery for ech of the designted study phses is shown in Tble 4-3. Figures 4-6 through 4-10 show the different types of clening events, nd their frequency throughout the study. Note tht the x-xis on Figures 4-9 nd 4-10 cover only three months (compred to six months for the other grphs), to better show the high frequency of clenings during Phse 3. 28

49 Tble 4-3. UF Unit: Clening Intervls, Avilbility, Filtrte Production nd Recovery Vlues 29 Study Period Units Phse 1 Interim Phse 2 Interim Phse 3 Selected Totl Vlues No. Dys in Period Clening Intervls for UF Unit No. CIPs (Citric, NOCl) No. ECs (Citric, NOCl, Micro-90) No. Soks (NOCl, overnight) No. CEBs (NOCl, 30 min) Intervl, CIPs & ECs dys Intervl, Soks & CEBs dys Opertionl Avilbility of UF Unit Filtrtion Time hours 5,044 3,218 2,722 Filtrtion Time dys Percent Filtrtion Time % Ave Bckwsh Intervl min Bckwsh Time (2.25 min Bckwshes) hours Totl Opertion Time dys Percent Opertion Time % Filtrte Production nd Recovery/Yield Ave Dily Flow Processed, gpd 58,578 57,749 58,981 59,082 49,877 Totl Flow Applied/Processed MG Totl Filtrte Produced MG Bckwsh Wter Usge MG Recovery/Yield %

50 Figure 4-6. UF System Clening Events During the First Hlf of Phse 1: June December, Dily Averge TMP vlues fter CIP C = Full CIP S = NOCl Overnight Sok 15 TMP (psi) S 3.3 S 2.9 C S C C S 4.7 C S Dte Figure 4-7. UF System Clening Events During the Second Hlf of Phse 1 nd the Interim Period: Jnury June, Dily Averge TMP vlues fter CIP C = Full CIP EC = Extended Clening B = Chemiclly Enhnced Bckwsh S = NOCl Overnight Sok TMP (psi) C S 4.9 C S S S 3 EC B B B B B B B S 3.6 S S 3.5 C 3.1 C S C Dte 30

51 Figure 4-8. UF System Clening Events During Phse 2: July December, Dily Averge TMP vlues fter CIP C = Full CIP EC = Extended Clening B = Chemiclly Enhnced Bckwsh S = NOCl Overnight Sok TMP (psi) B B B B B 3.48 C B B B B B B B B B B B B B B C C C B B B B S 5 C B B B B B S C EC Dte Figure 4-9. UF System Clening Events During the First Hlf of Phse 3: Jnury Mrch, 2012 TMP (psi) B B Dily Averge TMP vlues fter CIP B C B B B B C = Full CIP S = NOCl Overnight Sok C B B B C B B B B = Chemiclly Enhnced Bckwsh B = Improved Chemiclly Enhnced Bckwsh B C B S B B B B C B B B B B C Dte 31

52 Figure UF System Clening Events During the Second Hlf of Phse 3: April June, 2012 TMP (psi) B B Dily Averge TMP vlues fter CIP B C+S B B B B B C C = Full CIP S = NOCl Overnight Sok B B B B B B B C 8.31 B B B B B B B B B B B B B B B B BB BB B B B B BB B B B B B B B B B B S B = Improved Chemiclly Enhnced Bckwsh C C C 10.1 B B B B S 0 Dte Fouling nd the Effects of Clenings During Phse 1, full chemicl clen-in-plce (CIP) or extended clens (ECs) were required bout every 5 weeks, nd sodium hypochlorite (NOCl) soks or NOCl chemiclly enhnced bckwshes (CEBs) were performed every 18 dys on verge. The TMP immeditely fter the CIPs ws generlly below 5 psi. During Phse 2, the need for CIPs or ECs incresed to every 4 weeks, with CEBs or soks done every 6 dys. As in Phse 1, the TMP immeditely fter the CIPs ws generlly below 5 psi. During Phse 3, CIPs were performed every 2 weeks nd CEBs or soks were done every other dy, on verge. To mintin opertion during the finl two weeks of the study, CIPs were needed weekly nd CEBs were needed 1-2 times dy. Even fter performing multiple CIPs, the TMP could not be reduced to lower thn bout 9 psi. These results re consistent with 2009 Ornge County Wter District study (Knoell, 2011) tht compred Siemens membrnes mde of two different mterils: polypropylene nd PVDF (similr to the ones used in this project). Clening ws required t lest twice s often for the PVDF membrnes, with no flux dvntge. By the end of the six month study, CIPs were needed s frequently s every three dys long with dily CEBs. In ddition to the membrne fouling tht occurred during Phse 3, rin events nd winter conditions lso dversely ffected the feed wter qulity nd UF performnce. During these times, the mount of mteril incresed in the bsket striners upstrem of the UF; some of this mteril went through the striners nd cused dditionl loding on the UF membrnes. In ddition, TMP vlues were > 5 psi immeditely fter clening, even with incresed clening frequencies. For exmple, mjor rin event occurred during December 2010 (Phse 1), nd TMPs were restored to norml levels only fter removing the unit from service for severl dys in the spring of 2011 to do more thorough, extended clenings. 32

53 Productivity Overll, the UF unit ws in productive opertion bout 90 percent of the time during test Phses 1 nd 2 nd bout 80 percent of the time during Phse 3. On verge, the intervl between bckwshes ws 22 minutes in Phses 1 nd 2, but decresed in Phse 3 to 15minutes. At the end of Phse 3, the longest bckwsh intervl ws only 15 minutes (immeditely fter the CIPs), nd within severl dys decresed to bout four minutes, which ws the minimum vlue llowed by the UF control progrm. The resulting downtime from the more frequent bckwshes (nd other clening events) decresed the overll verge dily filtrte production by pproximtely 15%, from bout 59,500 gpd in Phses 1 nd 2 to bout 50,700 gpd in Phse 3. At the shortest bckwsh intervl of four minutes, filtrte production ws pproximtely 30,000 gpd, pproximtely hlf of the norml (non-fouled membrne) production. The bckwsh wter requirements were typiclly 7% of the totl mount of feed wter treted by the unit during Phses 1 nd 2, s expected. This vlue incresed to n verge of 9% during Phse 3, nd ws s high s 47% t the end of Phse 3. It should be noted tht the UF unit, even t the end of the study, ws still producing dequte mounts of filtrte, nd likely could hve continued to do so for some mount of time. However, continuing opertion would not hve been prcticl for long, due to the need for dily clening procedures, n incresed number of bckwshes, nd the decresed filtrte production. Bsed the inbility of repeted clenings to mintin membrne permebility, TMP, nd flux, the membrnes were considered to be irreversibly fouled t the end of the two-yer study period. This service life ws much shorter thn the expected vlue of five yers RO Opertion UF-RO Operting Prmeters The UF-RO system ws in opertion for pproximtely 2 yers (> 12,000 hours), from July 6, 2010 through June 28, 2012 nd treted over 14.7 million gllons of UF filtrte; note tht these dtes reflect the totl opertionl time, including time before the UF nd RO systems cme to stedy stte, nd the time between phses. Averge operting conditions for the RO system re shown in Tble 4-4. Throughout the study, the flux ws mintined t pproximtely 12 gfd, nd recovery ws pproximtely 85%. To help control inorgnic fouling, the trget dose of ntisclnt (Pretret Plus 0100, King Lee Technologies) ws 6.5 mg/l throughout the study, per the mnufcturer's recommendtion. Sulfuric cid ws lso used to lower the ph of the feed wter to reduce the precipittion of springly soluble slts. A single set of RO membrnes ws used during Phse 1. At the end of Phse 1, the led nd til elements were removed from the system for utopsy (Section 4.3.1). These elements were replced with new elements for Phse 2. Results during Phse 2 indicted reduced performnce (Section ); consequently, ll membrnes in the RO unit were replced with new elements in Phse 3. 33

54 Tble 4-4. Averge Operting Conditions of UF-RO System Prmeter Units Phse 1 Phse 2 Phse 3 Net Operting Time hours 5,204 3,537 3,292 Feed Flow gpm Permete Flow gpm Recovery % Specific Flux gfd Initil Pressure psi Second Stge Pressure psi Antisclnt Dose mg/l Sulfuric Acid Dose mg/l Influent ph Permete ph Concentrte ph Optimiztion of UF-RO Operting Prmeters Phse 1 estblished bseline conditions for the UF-RO. Sulfuric cid ws dded to the RO influent to chieve ph vlue of 6.5. In Phse 2, sulfuric cid ddition ws reduced bsed upon Lngelier sturtion index (LSI) clcultions. An nlysis of the concentrte wter qulity indicted tht the RO system could operte in LSI rnge of 0-1, with the ddition of 6.5 mg/l of ntisclnt. Consequently, the concentrte ph ws llowed to rise to trget of 7.2. This chnge incresed the feed wter ph to 6.8, nd decresed sulfuric cid use by 40% (from 162 to 97 mg/l). In Phse 3, new membrnes were used, nd modeling softwre (IMSDesign by Hydrnutics) ws lso used to optimize the opertion of the RO system. Modeling results, bsed on historicl feed wter qulity nd opertionl prmeters, indicted tht fouling in Stge 2 of the RO system could be reduced by decresing the recovery in Stge 1, thereby incresing the flow rte cross the membrnes in Stge 2, nd decresing the slt concentrtion nd fouling potentil of the wter. The proper mount of diversion ws ccomplished by incresing the bckpressure in the Stge 1 permete line to 34 psi. Other operting trgets remined the sme s in Phse 2: flux of 12 gfd, overll recovery of 85%, 6.3 mg/l of ntisclnt, nd trget concentrte ph of UF-RO System Performnce Dt The dt presented in this section re dily verges clculted from hourly dt collected utomticlly by the system loggers. The only exception ws during Phse 2, from October 27, 2011 through December 15, During this period, dt from the loggers ws corrupted; dily verges were clculted from vlues tht were mnully recorded twice per dy, once in the morning nd once in the fternoon. 34

55 Differentil Pressure Figure 4-11 presents the differentil pressure dt for the RO system, i.e., the drop in pressure from the RO feed to the RO concentrte, on the pressurized side of the membrne. The differentil pressure incresed stedily during Phse 1, which suggests deposition of mterils in the feed flow pth. Literture from the membrne mnufcturer indictes tht these mterils my include metl oxides, colloids, minerls, polymerized silic, microorgnisms, orgnics, nd ntisclnt (Hydrnutics, 2011). The clening procedures used on the RO system between Phses 1 nd 2 (see detils in Section ) hd little effect on the differentil pressure, which remined close to 25 psi. The differentil pressure ws reltively constnt during Phses 2 nd 3, which indicted miniml dditionl deposition. Figure UF-RO System: Differentil Pressure Dt 30 Differentil Pressure (psi) Phse 1 Phse 2 Phse 3 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture Figure 4-12 presents the temperture dt for the RO system on the UF trin. There ws cler sesonl vrition, with tempertures decresing from pproximtely 29 C in the summer to 22 C in the winter. Temperture is importnt to RO performnce, becuse incresing tempertures increse the diffusion rte through the membrne for both wter nd solutes. Consequently, s temperture increses, the flux of wter through the membrnes increses (or the feed pressure decreses in systems operted t constnt flux, such s this one). In ddition, s tempertures increse, solute concentrtions in the permete generlly increse s well (Kim et l., 2009). 35

56 Figure UF-RO System: Temperture Dt 35 Feed Temperture ( C) Phse 1 Phse 2 Phse 3 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Slt Pssge Slt pssge dt for the RO system on the UF trin re presented in Figure 4-13; the vlues were corrected for temperture nd permete flow ccording to the mnufcturer s softwre. The slt pssge ws level t pproximtely 1% for the first three months of opertion, incresed suddenly on October 8, 2010, then decresed until the end of Phse 1. Slt pssge throughout Phse 2 vried from %; these vlues were generlly higher thn those observed in Phse 1. In Phse 3, slt pssge strted t 1% but incresed over time to pproximtely 1.3%. Figure UF-RO System: Slt Pssge Dt Over Time Slt Pssge (%) Phse 1 Phse 2 Phse 3 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Most of these chnges cn be ttributed to the chnges in temperture, or opertionl conditions, s shown in Figure Much of the dt follows liner trend of incresing slt pssge with incresing temperture; this trend suggests tht the correction provided by the mnufcturer did not perfectly ccount for the wter temperture. In ddition to the temperture trend, severl 36

57 distinct periods cn be observed in Figure Weekly clibrtion of the conductivity nlyzer begn October 8, 2010, during Phse 1. The lower slt pssge vlues prior to tht dte re likely n rtifct, rther thn truly low vlues. Figure UF-RO System: Slt Pssge s Function of Temperture () All Dt, (b) Auto-logged Dt, with Weekly Clibrtion of the Anlyzer () 2.0 (b) 2.0 Slt Pssge (%) Phse 1, Before Weekly Clibrtions (Through 10/7/10) 0.5 Phse 1, After Weekly Clibrtions (After 10/7/10) Phse 2, Automticlly Logged Dt (Through 10/26/11) Phse 2, Mnul Mesurements (After 10/26/11) Phse Temperture ( C) Slt Pssge (%) Phse 1, With Weekly Clibrtions Phse 2, Automticlly Logged Dt Phse Temperture ( C) In ddition, dt from the utologger ws corrupted between October 26 nd December 15, 2011, during Phse 2. Vlues during this time were verges of two mnully recorded vlues tken once in the morning nd once in the fternoon. Slt pssge followed diurnl trend, with the slt pssge lowest t night under the coldest tempertures, nd incresing during the dy s tempertures incresed. The mnully recorded dt excluded the low nighttime slt pssge vlues, resulting in higher-thn-norml vlues for tht period. As show in Figure 4-14b, once the dt from these two opertionl periods were excluded, the slt pssge followed liner trend with temperture. There were no pprent differences in performnce mong Phses 1, 2, nd 3. Feed Pressure nd Flux Figure 4-15 presents feed pressure dt nd Figure 4-16 presents normlized specific flux dt for the UF-RO system; note tht the specific flux is directly relted to the feed pressure, nd decreses s feed wter pressure increses. With the new membrnes in Phses 1 nd 3, the feed pressure incresed from n initil vlue of pproximtely 150 psi to between 160 nd 170 psi fter bout two months. At the sme time, the specific flux decresed from pproximtely 0.12 to 0.10 gfd/psi. These chnges occurred while the temperture ws reltively constnt, nd re likely due to minor biologicl nd orgnic fouling tht inevitbly occurs during the conditioning of new membrnes. The membrnes were thought to hve reched stedy stte round October 2010 (Phse 1) nd Mrch 2012 (Phse 3), when the pressure nd flux vlues stbilized. However, the stedy stte during Phse 1 lsted only one to two months, fter which the temperture decresed, the feed pressure incresed, nd the specific flux decresed. By mid-mrch 2011, the feed pressure reched pproximtely 200 psi, nd the specific flux hd declined to 0.08 gfd/psi. Literture from the mnufcturer indictes tht feed pressure increses pproximtely 3% for every 1 C decrese in temperture (Hydrnutics, 2011b). Thus the 4 C decrese during Phse 1 would be expected to increse the feed pressure by pproximtely 12%, or 19 psi, to pproximtely 180 psi. However, feed pressure incresed beyond tht point, presumbly due to fouling. The Phse 3 dt show no cler indictions of fouling, beyond the initil conditioning period. 37

58 Figure UF-RO System: Feed Pressure nd Temperture 250 Feed Pressure Temperture Feed Pressure (psi) Temperture ( C) Phse 1 Phse 2 Phse /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Figure UF-RO System: Normlized Specific Flux 0.18 Normlized Specific Flux Temperture 30 Normlized Specific Flux (gfd/psi t 25 C) Phse 1 Phse 2 Phse /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture ( C) The specific flux is normlized for temperture; however, s shown by the slt pssge dt, temperture corrections re not lwys perfect. In this cse, the steepest decrese in the specific flux occurred t the end of Phse 1, when the temperture ws reltively constnt, so this decline ws likely due to fouling. As with the feed pressure, the Phse 3 dt show no cler indictions of fouling, beyond the initil conditioning period. 38

59 Clening of the UF-RO System The chnges in the RO operting performnce t the end of Phse 1 (described in the previous section) suggested tht the membrnes needed to be clened. As result, the RO system ws tken offline in mid-mrch Two membrne elements were removed for utopsy: one led element nd one til element. The elements tht were removed for nlysis were replced with new ones fter the RO system clening nd prior to strtup of Phse 2. The utopsy results re discussed in Section 4.3. Following the extrction of the two membrne elements for utopsy, clening of the membrne elements ws performed on the RO system. The system ws initilly clened with high ph solution contining sodium tripolyphosphte nd N-EDTA. This solution is recommended to remove fouling by clcium sulfte, orgnic mterils, divlent nd trivlent ctions, nd metl ions. A second clening solution of critic cid ws used to remove inorgnic scle, metl oxides nd hydroxides, nd inorgnic-bsed colloidl mtter. The composition of ech of the solutions ws specified by the mnufcturer (Hydrnutics, 2011). The effects of these clenings cn be seen in the Phse 2 dt in Section MBR TREATMENT TRAIN MBR Opertion The MBR pilot-scle system ws delivered to JWPCP in mid-june During preliminry strtup, the MBR ws supplied with JWPCP secondry effluent, nd the ertion tnk ws seeded with wter from JWPCP odor control biotrickling filter unit tht contined nitrifying bcteri. From August 12 to September 2, 2010, the MBR chieved nerly complete nitrifiction. Bsed on this preliminry work, it ws determined tht the entire volume of the ertion tnk (originlly designed for treting primry effluent) ws not needed for full nitrifiction. As result, the ertion tnk ws replced by smller tnk (Section 2.3.2). This chnge reduced the hydrulic retention time nd energy requirements, both importnt fctors in full-scle design nd opertion. In ddition to this structurl chnge, the membrnes underwent three restortion clenings before the strt of testing: detils on these clenings re given in Section A clen-wter membrne conditioning test performed on October 28, 2010, indicted tht both membrne cssettes were in cceptble condition. Testing of the MBR ws divided into three opertionl phses (Section 5.1), ech with different trget flux (Tble 4-5). These phses do not include dt tken during strtup of the MBR, pproximtely the first month of opertion. The following sections discuss the MBR operting prmeters (Section ), performnce dt (Section ), nd clenings (Section ) for the three phses of opertion. Tble 4-5. Opertionl Phses of the MBR System Phse Strt Dte End Dte Trget Flux (gfd) 1 12/8/10 3/30/ /5/11 12/6/ /20/12 6/30/

60 MBR System Operting Prmeters The operting prmeters for ech opertionl phse re summrized in Tble 4-6, nd membrne dt re summrized in Tble 4-7. The membrnes used in Phses 1 nd 2 were pproximtely eight yers old t the time the project begn; they were previously used to tret primry effluent t nother plnt operted by the Districts. It is possible tht the ge of the membrnes ffected the performnce, e.g., the fiber brekge tht occurred during Phse 2 (see TMP discussion in Section ). The membrnes used in Phse 3 were new. Influent flow, flux, nd hydrulic retention time (HRT) in the MBR pilot-scle system re plotted in Figures 4-17, 4-18, nd 4-19, respectively. The vlues shown in these figures re dily verges clculted from dt tken utomticlly every 5 min by system loggers; dt tken during opertionl interruptions were excluded from these clcultions. Tble 4-6. Averge Operting Conditions of the MBR System Prmeter Units Phse 1 Phse 2 Phse 3 Flows nd Flux Feed Flow gpm Flux gfd Hydrulic Retention Time (HRT) min Cyclic Bckpulse Intervl min * Durtion sec Flow gpm Biologicl Prmeters Membrne Tnk Mixed Liquor Suspended Solids (MLSS) mg/l 3,700 3,300 4,000 Solids Retention Time (SRT) dys Mixed Liquor Recircultion Rte gpm Air Scouring Rte scfm Aertion Rte in Aertion Tnk scfm Mintennce Clening Frequency per week NOCl Concentrtion mg/l Mnul Relxtions Frequency per week Durtion min *In response to TMP increses (Section ), the bckpulse intervl ws decresed to s low s 6 min from Februry 6-29, 2012; to 10 min from Mrch 5-12, 2012, nd to s low s 6 min from My 2-7,

61 Tble 4-7. Membrne Pck(s) in Service Phse Strt Dte End Dte Pck(s) in Service 1 12/8/10 3/30/11 Both* 2 7/5/11 7/15/11 North 7/15/11 10/6/11 South 10/6/11 10/7/11 North 10/7/11 12/6/11 South* 3 1/20/12 6/30/12 Single New Pck *Restortion clenings were conducted on Februry 24, 2011, nd October 11-13, 2011; no membrnes were in service during these clenings. Figure MBR System: Influent Flow Influent Flow (gpm) Phse 1 Phse 2 Phse 3 12/1/2010 4/24/2011 9/15/2011 2/6/2012 6/30/2012 Dte Figure MBR System: Flux Phse 1 Phse 2 Phse 3 Flux (gfd) /1/2010 4/24/2011 9/15/2011 2/6/2012 6/30/2012 Dte 41

62 HRT (min) Figure MBR System: HRT Phse 1 Phse 2 Phse 3 12/1/2010 4/24/2011 9/15/2011 2/6/2012 6/30/2012 Dte During Phse 1, the system ws operted with both membrne pcks in service t flux of 10 gfd, which is typicl flux vlue for MBR units tht tret primry effluents. Mintennce clens were conducted weekly; detils on the clenings cn be found in Section The influent flow nd HRT were firly constnt t 29 gpm nd 73 min, respectively. SRT ws controlled by removing mixed liquor (i.e., solids) from the membrne tnk vi n overflow system. During Phse 2, the verge flux through the membrnes ws incresed to 14 gfd. To chieve this flux, only one of the two membrne pcks ws used nd the influent flow ws decresed to n verge of 21 gpm, resulting in n verge HRT of 96 min. The flux, flow, nd HRT were reltively constnt during Phse 2, except during October 2011; this period is discussed in more detil in Section The membrne pck in service ws lternted between the two pcks, which were designted the north nd south pcks. Pck chnges were driven by operting conditions, which re described in more detil in Section Mintennce clenings were replced by mnul relxtions performed three times per week (see Section for detils). The clenings were eliminted becuse the chlorine dded during the mintennce clenings ws considered to be possible cuse for difficulties in mintining the desired mixed liquor suspended solids (MLSS) concentrtions during Phse 1. A peristltic pump ws dded to the system to better control solids removl nd the SRT. For Phse 3, the flux ws incresed to 20 gfd, vlue similr to the UF flux, nd ws held constnt t this vlue throughout the period. To chieve this flux, the system ws operted t n influent flow of 34 gpm nd n verge HRT of pproximtely 74 min. A new membrne cssette with new ZeeWeed 500d membrnes ws instlled. To ccommodte the new membrnes, the depth of the membrne tnk ws incresed (see Section for detils on the system modifiction). Becuse the peristltic pump instlled during Phse 2 improved SRT control, weekly mintennce clens were reinstted during Phse 3; mnul relxtions were lso performed twice per week (see Section for detils on the clenings nd relxtions) MBR System Performnce Dt This section describes the opertionl performnce of the MBR system. MLSS vlues were mesured by the JWPCP Lbortory in grb smples tken from the membrne tnk. The other vlues shown in this section re dily verges clculted from dt tken utomticlly every 42

63 5 min by system loggers, except where noted; dt tken during opertionl interruptions were excluded from these clcultions. It is worth noting tht despite some of the difficulties described in this section, the MBR consistently nitrified the JWPCP secondry effluent throughout the study, s described in Chpter 5. Temperture Temperture dt for the MBR mixed liquor re plotted in Figure Tempertures before September 10, 2011, re the verge of mnully recorded dily observtions; tempertures fter this dte re dily verges clculted from dt tken utomticlly every 5 min by system loggers. As with the UF nd UF-RO dt, there ws cler sesonl vrition, with tempertures decresing from pproximtely 33 C in the summer to 24 C in the winter. Temperture cn ffect performnce, with incresing tempertures decresing wter viscosity. In systems such s this one tht re operted t constnt flux, decrese in wter viscosity decreses the feed pressure nd TMP, nd increses the flux nd permebility. In ddition, lower tempertures slow down biologicl ctivity. Temperture ( C) Figure MBR System: Temperture 5 0 Phse 1 Phse 2 Phse 3 12/1/2010 4/24/2011 9/15/2011 2/6/2012 6/30/2012 Dte SRT nd MLSS The results for MLSS nd SRT re plotted in Figures 4-21 nd 4-22, respectively. In generl, severl fctors re blnced in selecting trget MLSS vlues: higher MLSS levels llow for more compct rector nd reduce construction costs, but cn led to membrne fouling t high concentrtions. In ddition, incresing MLSS requires more ir for membrne scouring nd for ertion, becuse the lph correction fctor for oxygen trnsfer efficiency decreses with incresing MLSS (Asno, 2007); higher ir usge rtes increse the energy requirements nd operting costs. MBR units usully tret primry effluent, with MLSS vlues of 8,000-10,000 mg/l nd SRT vlues of 5-20 dys (Tchobnoglous, 2003). For this project, the MBR ws used to further oxidize the orgnic mtter in the JWPCP secondry effluent nd to nitrify the secondry effluent. Bsed on mnufcturer recommendtions, the MLSS concentrtions were generlly mintined between 3,000 nd 4,000 mg/l. The MLSS level ws controlled by the SRT; incresing the SRT incresed the MLSS concentrtions nd vice vers, lthough the exct reltionship is complicted due to vritions in biosolids production nd decy rtes. 43

64 Figure MBR System: MLSS MLSS (mg/l) Phse 1 Phse 2 Phse 3 12/1/2010 4/24/2011 9/15/2011 2/6/2012 6/30/2012 Dte Figure MBR System: SRT SRT (dys) Phse 1 Phse 2 Phse 3 12/1/2010 4/24/2011 9/15/2011 2/6/2012 6/30/2012 Dte As shown in Figure 4-22, SRT levels were most vrible during Phse 1. This issue ws mitigted during Phse 2 by chnging the solids wsting system from n overflow system, which ws prone to clogging, to peristltic pump. As result, SRT vlues were more consistent during Phses 2 nd 3, lthough the SRT ws intentionlly incresed twice during ech phse. The first increse occurred t the beginning of Phse 2, in response to fouling issues (see TMP discussion below). The second increse during Phse 2 occurred in October 2011, in response to decrese in MLSS. A restortion clening ws performed on October 12, 2011 (detils in Section ) nd ppered to disrupt the MLSS concentrtions, which dropped to less thn 1,600 mg/l fter the clening. It is uncler why this restortion clen hd lrger impct on MLSS concentrtions thn similr clening conducted on Februry 24, 2011, but the SRT ws incresed to pproximtely 21 dys, nd the MLSS returned to pre-clening levels pproximtely three weeks lter. 44

65 At the strt of Phse 3, the MBR ws operting t SRT of pproximtely 9 dys; however, this SRT vlue proved to be too low to mintin the trget MLSS concentrtion of pproximtely 4,000 mg/l. In response, the SRT ws rised to dys in erly Februry 2012, nd the MLSS recovered to the desired level. The MLSS concentrtion lso decresed in June 2012; incresing the SRT to 14 dys successfully rised the MLSS concentrtion bck to the trget levels. TMP nd Permebility TMP nd permebility dt for the MBR re plotted in Figures 4-23 nd 4-24, respectively. The permebility is clculted by dividing the flux by the TMP. Becuse the flux ws reltively constnt (Figure 4-18), permebility decresed when the TMP incresed in n lmost directly inverse reltionship. For simplicity, only the TMP dt re discussed below. However, the following explntions pply to the trends in both the TMP nd permebility. Figure MBR System: TMP TMP (psi) Phse 1 Phse 2 Phse /1/2010 4/24/2011 9/15/2011 Dte 2/6/2012 6/30/2012 Permebility (gfd/psi) Figure MBR System: Permebility 14 Phse 1 Phse 2 Phse /1/2010 4/24/2011 9/15/2011 Dte 2/6/2012 6/30/

66 Figure 4-25 plots the TMP dt with the MLSS concentrtion, which ppered to ffect the TMP. Most of the TMP spikes coincided with decrese in MLSS concentrtion below 4,000 mg/l: during Phse 1 in Februry nd Mrch 2011, throughout Phse 2, nd during Phse 3 in Februry nd June These spikes my hve been cused by MLSS levels tht were too low to remove fouling colloids or lrger prticles, or simply coincidence due to n increse in the concentrtions or types of foulnts in the MBR feed wter. The fouling ws reversible, nd norml TMP vlues were re-estblished for the first spike in Phse 1 by citric cid restortion clening on Februry 24, 2011, nd decrese in the cyclic bckpulse intervl from 11 min to s low s 6 min from Februry 6 to Februry 29, 2012, nd to 10 min from Mrch 5 to Mrch 12, 2012 (see Section for detils on the clening nd bckpulse methods). For the second spike in Phse 1 nd both spikes in Phse 3, norml TMP vlues were re-estblished incresing MLSS level bck to 4,000 mg/l. During Phse 2, the increses in TMP were generlly mnged by chnging the membrne pck tht ws in opertion. The system ws strted with the north pck in service on July 5, The TMP rpidly incresed to 7 psi nd the permebility decresed to 2 gfd/psi over the following week. On July 15, 2011, the north membrne pck ws replced with the south membrne pck. Over the next three months, the TMP on the south pck incresed to lmost 8 psi nd the permebility decresed to pproximtely 2 gfd/psi. On October 6, 2011, the south membrne pck ws replced by the north membrne pck, which hd been out of service for lmost three months, effectively providing very long relxtion period; no other clenings were performed. The turbidity in the permete incresed more thn ten-fold, from 0.08 NTU to > 1 NTU. High turbidity vlues re n indiction of dmge to the membrne fibers; the ge of the membrnes (pproximtely nine yers old t the time) my hve been fctor in the dmge. This brupt decline in wter qulity dversely ffected the downstrem RO unit, s discussed in Section The south membrne pck ws plced bck in service on October 7, 2011, but t reduced influent flow nd flux (Figure 4-17 nd 4-19), due to the membrne fouling. Figure MBR System: TMP nd MLSS 6000 MBR MLSS (mg/l) TMP 12 MLSS (mg/l) TMP (psi) Phse 1 Phse 2 Phse /1/2010 4/24/2011 9/15/2011 2/6/2012 6/30/2012 Dte 46

67 A restortion clening ws performed on October 12, 2011, fter which the influent flow nd flux were slowly rmped up to the trget vlues of 23 gpm nd 15 gfd over the following month, s the MLSS concentrtion recovered. The restortion clening restored the TMP to below 2 psi, nd the permebility to pproximtely 7 gfd/psi. From tht point until the end of Phse 2, the TMP slowly incresed nd the flux slowly decresed. These trends were similr to the behvior during August nd September, nd were probbly due to fouling of the membrnes. A few smller increses in TMP occurred when the MLSS concentrtions were > 4,000 mg/l: during Phse 1 in lte December 2010, nd during Phse 3 t the end of Mrch, middle of April, nd beginning of My Although the cuses of these TMP increses were not definitively identified, they could be cused by chnges in the secondry effluent wter qulity (Chpter 5), similr to the UF (Section ). However, the TMP increses were temporry nd generlly did not require ny chnge in opertions. The only exception ws the fouling event t the beginning of My 2012; for this event, the bckpulse intervl ws decresed to s low s six minutes, nd the foulnt wshed out or ws degrded by the mixed liquor. On My 7, 2012, the system ws returned to the norml bckpulse intervl of 11 minutes, nd remined t tht vlue through the end of the project. The lst observed trend TMP ws slow decrese over most of Phse 3 (with the exception of the fouling effects described bove). This decrese my be due to incresing temperture nd decresing wter viscosity Clening of the MBR System nd Relxtion of the Membrnes Clenings nd relxtions were used to reduce fouling of the MBR membrnes. There were three types of clenings (cyclic bckpulses, utomted mintennce clenings, nd restortion clenings), nd two types of relxtions (cyclic nd mnul). Tble 4-6 summrizes the frequency of the three kinds of regulrly scheduled mintennce: cyclic bckpulses, utomted mintennce clenings, nd mnul relxtions. The MBR system could be operted in either cyclic bckpulse or cyclic relxtion mode. Cyclic bckpulse mode ws lmost lwys used, except during the system check nd for short periods fter mjor system upsets. Cyclic bckpulses were performed t 11 min intervls throughout most of the study. For ech cycle, permete production ws stopped by turning off the permete pump nd closing the product line vlves. Permete ws then pumped bck through only the membrne pck(s) in service, t 15 gfd for 45 seconds. Production ws then resumed. Aerobic recircultion nd ir scouring were mintined throughout the cycle. Cyclic relxtions were similr to cyclic bckpulses, but the bckpulses were eliminted nd permete production ws simply stopped for tht period of time. Automted mintennce clenings were conducted weekly during Phses 1 nd 3. Sodium hypochlorite ws dded to trget dose of 200 mg/l to the MBR permete line; the permete flow ws then pumped bck through the membrnes in bckpulses t flux of 15 gfd. The first bckpulse ws 2 min long, followed by totl of six 45-second bckpulses t 2-min intervls. During the bckpulsing cycle, the erobic recircultion pump nd the ir scour in the membrne tnk were turned off. Becuse the recircultion pump ws the only source of influent wter into the membrne tnk, the system erted the mixed liquor nd recirculted the flow for 10 min fter the bckpulsing cycle, to ensure tht the membrnes were fully submerged before beginning permete production. 47

68 Mnul relxtions replced the utomted mintennce clenings in Phse 2, nd were used in ddition to the utomted mintennce clenings in Phse 3. During the mnul relxtions, permete production ws stopped for 45 minutes, but recircultion nd ir scour were mintined. Restortion clenings re nlogous to the CIPs for the UF unit, nd were conducted s needed, with sodium hypochlorite nd/or citric cid. The recircultion nd ir scour were turned off for the durtion of ech clening. The membrne tnk ws emptied, nd the membrnes were rinsed off with hose. The bckwsh permete tnk ws dosed with the clening gent, nd the entire 800-gl volume ws bckwshed through the membrnes t flux of pproximtely 12 gfd. The membrne tnk ws then topped with potble wter (for totl volume of 1,600 gl during Phses 1 nd 2, nd 2,000 gl during Phse 3), nd the membrnes were soked for durtion of three hours to overnight. Sodium hypochlorite ws dosed into the permete tnk to provide trget concentrtion of 1,000 mg/l during this sok, with no ph djustment; citric cid ws dosed to trget concentrtion of 2,000 mg/l, nd muritic cid ws dded to the membrne tnk to djust the ph to After the sok, the tnk ws drined, rinsed, nd refilled with mixed liquor tht hd been stored in the ertion tnk. The restortion clenings performed on the MBR during this study re summrized in Tble 4-8. Tble 4-8. Restortion Clenings for the MBR Phse Dte Clening Agent Trget Sok Dose Durtion (mg/l) Prelim 9/2/10 NOCl 1 1,000 3 hours Strtup 9/26/10 Citric cid 2 2,000 Overnight 10/27-28/10 NOCl 1,000 Overnight 1 2/24/11 Citric cid 2 2,000 3 hours Interim 6/6-7/11 Citric cid 2 /NOCl 3 2,000/1,000 Overnight/4 hours 2 10/11-13/11 Citric cid 2 /NOCl 3 2,000/1,000 Overnight/Overnight 1 This restortion clening did not use bckwsh; insted, sodium hypochlorite ws dded to the membrne tnk s it ws filled with potble wter. 2 When citric cid ws used s the clening gent, muritic cid ws used to djust the ph to during the sok cycle of the restortion clening. 3 As with the other clenings, MBR permete ws used to mke the citric cid solution. Becuse the citric cid clening used the entire volume of the bckwsh tnk, permete ws unvilble for the NOCl clening tht followed. Therefore, the NOCl solutions were mde with potble wter. In Phses 1 nd 2, the bckwshes for the mintennce nd restortion clenings were generlly flushed through both pcks, even when only one pck ws in service during Phse 2. The only exception ws the lst restortion clen in October 2011, where the bckwsh flow to the south pck ws insufficient for clening (presumbly due to membrne dmge on the north pck), so the feed to the north pck ws prtilly closed. Both pcks were lso exposed to the soks within the membrne tnk during the restortion clenings in Phses 1 nd 2. In Phse 3, the membrne tnk contined only one membrne to bckwsh; no restortion clenings were necessry in this opertionl phse. 48

69 4.2.2 RO Opertion MBR-RO Operting Prmeters The MBR-RO system ws in opertion for pproximtely 1.5 yers (> 9,000 hours), from December 8, 2010 through June 30, 2012 nd treted over 8.8 million gllons of MBR permete; note tht these dtes reflect the totl opertionl time, including time before the MBR nd RO systems cme to stedy stte opertions, nd the time between phses. Averge operting conditions for the RO system re shown in Tble 4-9. Throughout the study, the flux ws mintined t pproximtely 12 gfd, nd recovery ws pproximtely 85%. As with the UF-RO, ntisclnt (Pretret Plus 0100, King Lee Technologies) nd sulfuric cid were used to help control inorgnic precipittion nd fouling. To control biofouling, pproximtely 0.7 mg N/L of mmoni ws dded to the fully nitrified MBR permete, followed by chlorine ddition to form chlormines. The trget combined chlorine residul ws 2 mg/l. Tble 4-9. Averge Operting Conditions of MBR-RO System Prmeter Units Phse 1 Phse 2 Phse 3 Net Operting Time hours 2,549 2,850 3,606 Feed Flow gpm Permete Flow gpm Recovery % Specific Flux gfd Initil Pressure psi Second Stge Pressure psi Antisclnt Dose mg/l Sulfuric Acid Dose mg/l Influent ph Permete ph Concentrte ph A single set of RO membrnes ws used during Phse 1. At the end of Phse 1, the led nd til elements were removed from the system for utopsy (Section 4.3.1). These elements were replced with new elements for Phse 2. Results during Phse 2 indicted reduced performnce (Section ); consequently, ll membrnes in the RO unit were replced with new elements in Phse Optimiztion of MBR-RO Operting Prmeters Phse 1 estblished bseline conditions for the RO system. Sulfuric cid ws dded to the RO influent to chieve ph vlue of 6.5. Antisclnt ws dosed t 3.3 mg/l, slightly lower thn the mnufcturer s recommended dose, due to dosing problems t the beginning of the phse. In Phse 2, sulfuric cid ddition ws reduced bsed upon Lngelier sturtion index (LSI) clcultions. An nlysis of the concentrte wter qulity indicted tht the RO system could operte in LSI rnge of 0-1, with the ddition of 6.5 mg/l of ntisclnt. Consequently, the 49

70 ntisclnt dose ws incresed, nd the concentrte ph ws llowed to rise to trget of 7.3. This chnge incresed the feed wter ph to 7.1, nd decresed sulfuric cid use by 95% (50 mg/l). In Phse 3, new membrnes were used, nd modeling softwre (IMSDesign by Hydrnutics) ws lso used to optimize the opertion of the RO system. Modeling results, bsed on historicl feed wter qulity nd opertionl prmeters, indicted tht fouling in Stge 2 of the RO system could be reduced by decresing the recovery in Stge 1, thereby incresing the flow rte cross the membrnes in Stge 2, nd decresing the slt concentrtion nd fouling potentil of the wter. The proper mount of diversion ws ccomplished by incresing the bckpressure in the Stge 1 permete line to 30 psi. Other operting trgets remined the sme s in Phse 2: flux of 12 gfd, overll recovery of 85%, 6.5 mg/l of ntisclnt, nd concentrte ph of MBR-RO System Performnce Dt The dt presented in this section re dily verges clculted from hourly dt collected utomticlly by the system loggers. Differentil Pressure Figure 4-26 presents the differentil pressure dt for the RO system, i.e., the drop in pressure from the RO feed to the RO concentrte, on the pressurized side of the membrne. The vlues were reltively constnt t pproximtely 20 psi cross ll three phses, but the dt were more scttered during Phse 2. Overll, the results indicte tht there ws no deposition of mterils in the feed flow pth. Figure MBR-RO System: Differentil Pressure Dt 30 Differentil Pressure (psi) Phse 1 Phse 2 Phse 3 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture Figure 4-27 presents the temperture dt for the RO system on the MBR trin. There ws cler sesonl vrition, with tempertures decresing from pproximtely 30 C in the summer to 24 C in the winter. Temperture is importnt to RO performnce, becuse incresing tempertures increse the diffusion rte through the membrne for both wter nd solutes. Consequently, s temperture increses, the flux of wter through the membrnes increses (or the feed pressure decreses in systems operted t constnt flux, such s this one). In ddition, s tempertures 50

71 increse, solute concentrtions in the permete generlly increse s well. Becuse Phse 1 on the MBR ws conducted entirely during the winter months, the temperture ws reltively low nd constnt. Tempertures were reltively high nd constnt during the first hlf of Phse 2, followed by decresing tempertures. Conversely, Phse 3 begn with low tempertures tht begn to increse midwy through the phse. Figure MBR-RO System: Temperture Dt 35 Feed Temperture ( C) Phse 1 Phse 2 Phse 3 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Slt Pssge Figure 4-28 presents the slt pssge dt for the RO system on the MBR trin. The slt pssge decresed from 1.0 to 0.5% during Phse 1, nd vried between 1.2% nd 1.6% during Phse 2. In Phse 3, slt pssge strted t 0.7% but incresed over time to pproximtely 1.2%. Some of these chnges cn be ttributed to the chnges in temperture, s shown by the correltion between temperture nd slt pssge (Figure 4-28b); the purple squres represent dt tken fter October 2011, when the MBR suffered membrne fiber dmge nd the turbidity ws briefly >1 NTU in RO feed wter. () Slt Pssge (%) Figure MBR-RO System: Slt Pssge Dt s Function of () Time nd (b) Temperture (b) Slt Pssge (%) Phse 1 Phse 2, Through 10/6/11 Phse 2, After 11/7/11 Phse 3 Phse 1 Phse 2 Phse /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture ( C) 51

72 Feed Pressure nd Specific Flux Feed pressure dt re presented in Figure 4-29, nd normlized specific flux dt re presented in Figure 4-30; note tht the specific flux is directly relted to the feed pressure, nd decreses s feed wter pressure increses. With the new membrnes in Phses 1 nd 3, the feed pressure incresed from n initil vlue of pproximtely 140 psi to between 160 nd 170 psi within the first two months of opertion. At the sme time, the specific flux decresed from pproximtely 0.12 to 0.09 to 0.10 gfd/psi. These trends re likely due to minor biologicl nd orgnic fouling tht inevitbly occurs during the conditioning of the new membrnes. Figure MBR-RO System Feed Pressure nd Temperture 250 Feed Pressure Temperture 30 Feed Pressure (psi) Temperture ( C) Phse 1 Phse 2 Phse /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Figure MBR-RO System Normlized Specific Flux 0.18 Normlized Specific Flux Temperture 30 Normlized Specific Flux (gfd/psi t 25 C) Phse 1 Phse 2 Phse /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture ( C) 52

73 The membrnes were thought to hve reched stedy stte round Jnury 2011 (Phse 1) nd Mrch 2012 (Phse 3). The system ws generlly stble during the stedy-stte periods of Phses 1 nd 3, nd during Phse 2, once temperture fluctutions re tken into ccount. Literture from the mnufcturer indictes tht feed pressure increses pproximtely 3% for every 1 C decrese in temperture (Hydrnutics, 2011b). Thus the 5 C decrese during Phse 2 would be expected to increse the feed pressure by pproximtely 15%, or 21 psi, from 140 to 161 psi, while the 3 C increse during Phse 3 would be expected to decrese the feed pressure by pproximtely 9%, or 15 psi, from 170 to 155 psi. These predictions mtch the observed feed pressures well. The only interruption to the stedy stte conditions occurred in Februry 2011 (Phse 1). Figure 4-31 presents hourly dt for the feed pressure nd normlized specific flux during this period; the temperture ws reltively constnt t pproximtely 24 C. The issues strted just fter midnight on Februry 26, 2011, when the MBR went into stndby mode nd stopped supplying wter to the RO, which cused the RO unit to shut down s well. On Februry 27, 2011, both the MBR nd RO were re-strted. The feed pressure to the RO incresed, nd the specific flux decresed, which is typicl t strt-up; however, the vlues did not return to norml levels. Figure MBR-RO System: Feed Pressure nd Normlized Specific Flux After MBR Shutdown on Februry 26, Verticl Lines on Grph Indicte Clenings Feed Pressure (psi) Feed Pressure Normlized Specific Flux /20/11 2/25/11 3/2/11 3/7/11 3/12/11 Dte Normlized Specific Flux (gfd/psi) Consequently, high ph clening ws performed on Mrch 4, 2011; detils re provided in the next section. Immeditely fterwrd, the feed pressure decresed slightly, from pproximtely 190 to 180 psi, nd the specific flux incresed slightly, from pproximtely gfd/psi to gfd/psi. However, on Mrch 6, 2011, the feed pressure incresed nd the flux decresed gin, so second clening ws performed the next dy with n even higher ph solution (detils provided in the next section). The second clening restored the feed pressure to the stedy-stte vlue of pproximtely 170 psi, nd the specific flux to 0.09 gfd/psi, ner the stedy-stte level. 53

74 Clening of the MBR-RO System Three clenings were performed on the MBR-RO system. The first two were prompted by problems following shutdown of the RO unit, nd the third ws conducted between Phses 1 nd 2. The first clening, on Mrch 4, 2011, ws bsed on mnufcturer informtion (Hydrnutics, 2011) nd used sodium hydroxide solution, with trget ph of 9.5 in the feed wter. Sodium hydroxide ws dosed t 65 mg/l for 30 minutes. The feed to the RO unit ws reduced to n verge of 10.1 gpm, resulting in feed pressure of 50 psi. The recovery throttle vlve ws opened ll the wy to promote flow cross the membrnes nd scour the surfces rther thn pushing the flow through the membrnes, which could force fouling mteril deeper into the membrne. Sulfuric cid nd ntisclnt were not dosed to the feed wter during the clening. The second clening ws conducted on Mrch 7, 2011, nd ws bsed on recommendtions from King Lee Technologies. A sodium hydroxide solution ws used, with trget ph of 11.5 in the feed wter. Sodium hydroxide ws dosed t 256 mg/l for pproximtely one hour. Similr to the previous clening, the feed to the RO unit ws reduced, to n verge of 10.7 gpm, nd sulfuric cid nd ntisclnt were not dosed to the feed wter. The MBR-RO system ws tken offline t the end of Mrch 2011, in prllel with the UF-RO system. Similr to the UF-RO, two membrne elements were removed for utopsy: one led element nd one til element. The elements tht were removed for nlysis were replced with new ones fter the RO system clening nd prior to strtup of Phse 2. The utopsy results re discussed in Section 4.3. Following the extrction of the two membrne elements for utopsy, clening of the membrne elements ws performed on the RO system. The clening protocol nd solutions were the sme for the UF-RO nd MBR-RO units. The RO system ws initilly clened with high ph solution contining sodium tripolyphosphte nd N-EDTA. This solution ws recommended to remove fouling by clcium sulfte, orgnic mterils, divlent nd trivlent ctions, nd metl ions. A second clening solution of citric cid ws used to remove inorgnic scle, metl oxides nd hydroxides, nd inorgnic-bsed colloidl mtter. The composition of ech of the solutions ws specified by the mnufcturer (Hydrnutics, 2011). 4.3 AUTOPSY RESULTS FROM RO MEMBRANE ELEMENTS Membrne utopsies were conducted on the led nd til RO elements on both the UF nd MBR trins t the end of Phse 1 (Mrch 30, 2011), nd on the led nd til RO elements on the MBR trin t the end of Phse 3 (June 30, 2011). The Phse 1 utopsy results re discussed in Section 4.3.1, nd the Phse 3 utopsy results re discussed in Section A summry of the findings re presented here; the full reports re provided in Appendix D Phse 1 Autopsies The April 2011 utopsy found no visully-observble evidence of physicl dmge to the overll structure of the membrnes. However, the productivity nd permebility of the membrnes were below mnufcturer specifictions, with the til RO element from the UF trin hving the worst performnce (66% nd 43% below mnufcturer specifictions for productivity nd permebility, respectively). In performnce tests on the membrne elements nd membrne smple coupons, slt rejection ws percentge points below the mnufcturer specifiction. 54

75 Anlyses of the membrnes suggested both biologicl nd inorgnic fouling. Visul exmintions, opticl imging, light microscope nlysis, FTIR nlysis, nd SEM-EDS nlysis indicted the presence of thin lyer of brown foulnt mteril on the membrne surfces of ll membrne elements, with the til RO element from the UF-RO system ppering to be most fouled. The foulnt lyers were composed of both orgnic nd inorgnic mterils (with silicon, clcium, iron, nd possibly sulfur s primry inorgnic constituents). Biologicl exmintion reveled trce grm-positive bcteri in the led RO element of the UF-RO system nd possible fungi in the led RO element of the MBR-RO system. Fujiwr test results indicted membrne hlogention (due to chlorine exposure) of ll RO membrne elements, except for the til element from the UF-RO system. The foulnt mterils were removed through clening, nd the RO membrne permebility ws recovered to within or bove mnufcturer s specifictions. However, slt pssge (i.e., slt trnsport coefficient) ws significntly elevted (by up to % nd % bove mnufcturer specifictions for the membrne smples from the UF-RO nd MBR-RO systems, respectively. These results were consistent with the hypothesis of membrne fouling, long with hlogen degrdtion of the membrne: when the foulnt mterils were removed, the permebility incresed, but the dmged membrne llowed pssge of slts. The utopsy results were lso consistent with the observtion tht the specific fluxes incresed fter the membrnes were clened; this trend ws more pprent on the UF-RO membrnes, which the utopsy showed to be more hevily fouled. Dmge to polymide RO membrne is known to occur with exposure to free chlorine, while chlormines hve miniml rectivity with the membrnes (Cussernd et l. 2008; Shemer nd Semit, 2011). However, reserch hs shown tht concentrtions of ferrous iron s low s 0.05 mg/l, in combintion with chlormines, cn led to enhnced oxidtion nd dmge of polymide RO membrnes (Gbelich et l., 2004; Gbelich et l., 2005; Knoell, 2006). Totl iron concentrtions in the UF nd MBR permetes were pproximtely 0.1 to 0.4 mg/l, nd nlysis of n MBR-RO permete smple indicted tht dominnt species ws ferrous iron. Becuse chlormines were pplied to the effluent upstrem of both RO units, this mechnism my hve led to the observed degrdtion of the RO membrnes in this project Phse 3 Autopsies The June 2012 utopsy found no visully-observble evidence of physicl dmge to the overll structure of the membrnes. The productivities of the led RO elements from the UF-RO nd MBR-RO systems were slightly lower thn norml by 8% nd 15%, respectively. However, performnce testing of the led element membrne smple coupons reveled norml wter productivity levels, suggesting tht fouling in the led elements ws loclized nd in the erly stges. Til element productivities were significntly below norml for both the UF-RO (by 41%) nd MBR-RO (by 25%) systems. The performnce of the til elements ws consistent with results from smple coupon performnce testing. Performnce testing lso reveled norml or ner norml levels of slt rejection (i.e., within 0.1% of expected norml performnce). Anlyses of the membrnes suggested both biologicl nd inorgnic fouling. Internl visul exmintions, opticl imging, light microscope nlysis, FTIR nlysis, SEM-EDS, nd CEI nlysis indicted the presence of thin lyer of brown foulnt mteril on the membrne surfces of ll membrne elements, with the til RO element from the UF-RO system ppering to be most fouled. The foulnt lyers were primrily composed of metl silictes, cly, nd ironbering grnulr mteril, s well s grm negtive bcteri nd morphous orgnic mteril. 55

76 Fujiwr test results were negtive for smples tken from the led nd til RO elements of the UF-RO system, but were positive for membrne smples tken from the led nd til RO elements of the MBR-RO system. The foulnt mterils were removed through clening, nd the RO membrne permebility ws recovered to within or bove mnufcturer s specifictions. Clening resulted in slight elevtion of the slt pssge, however the levels remined within the mnufcturer s specifictions. 4.4 COMPARISON OF THE UF AND MBR TREATMENT TRAINS UF vs MBR Both the UF nd MBR successfully treted secondry effluent from the JWPCP prior to RO tretment, nd both were operted successfully t flux of pproximtely 20 gfd. The UF hd the dvntge of simplicity over the MBR: it hd smller footprint, nd becuse it lcked biologicl tretment, it required fewer components, nd less process ir nd energy. The UF lso recovered from process upsets more quickly; dys or weeks were sometimes required to bring the MLSS concentrtion in the MBR bck to the desired vlue fter n upset. However, the UF ws prone to fouling nd ws more sensitive thn the MBR to chnges in the JWPCP secondry effluent wter qulity due to events such s rin storms. The greter resistnce to fouling by the MBR membrnes my be due to biologicl ctivity, which my ttenute nd degrde some orgnic foulnts in the secondry effluent, or could be due to the opertion nd clening cycles on the MBR, in which the membrnes re designed to operte in the concentrted environment of mixed liquor. As prcticl impliction of this difference, the MBR my require less clening mintennce thn the UF, prticulrly towrd the end of the membrne life. In ddition, the membrne life my be significntly longer for the MBR; in this study, the UF membrne life ws only two yers, much less thn the expected lifetime of five yers. More work is needed to ensure tht the MBR membrnes continue to perform effectively over the long term RO Units The most striking difference in opertions between the two RO units ws in the use of chemicls. The sulfuric cid doses for the UF tretment trin were between 97 nd 162 mg/l, wheres the doses used for the MBR tretment trin were between 3 nd 53 mg/l. These differences re due to the nitrifiction rection tht occurs in the MBR, which produces cid nd consumes lklinity in the wter, thereby reducing the buffering cpcity nd the scling potentil of the effluent. The cost svings from the reduced chemicl use could be significnt dvntge for the MBR-RO tretment process over the UF-RO tretment process. With respect to the performnce dt, the two RO units hd similr vlues nd trends for the feed pressure nd specific flux. The differentil pressure incresed in the UF-RO, but not the MBR- RO during Phse 1; no increses were observed in either RO unit during Phses 2 nd 3. The slt pssge vlues were slightly lower in the MBR-RO thn the UF-RO. More dt re needed to determine whether these observed differences in the differentil pressure nd slt pssge re reproducible or significnt. 56

77 4.5 SUMMARY UF For this project, the Siemens UF unit ws equipped with PVDF membrne elements nd used to tret non-nitrified, secondry-effluent, produced by high-purity oxygen ctivted sludge process operting t low SRT (< 3 dys). The unit performed relibly nd provided cceptble RO pretretment for period of pproximtely two yers. In Phses 1 nd 2 of the study, membrne clening intervls were cceptble with CIPs required no more frequently thn bout every four weeks nd CEBs not needed more thn weekly. In Phse 3 of the study, however, the necessry CIP frequency incresed to bout every two weeks, nd dily CEBs were required. At the end of the two-yer study period, the PVDF membrnes pper to be permnently fouled, with irreversible fouling becoming evident in the lst six months of opertion. Bsed on the results of this study, the tested Siemens PVDF membrnes with 0.04 micron pore size my not be pproprite for reuse pplictions of the JWPCP secondry effluent. This study hs clerly demonstrted the vlue of long-term, site-specific, comprtive evlutions with membrnes of vrious mterils (polypropylene, Teflon, PVDF, etc.): some performnce issues in this project were only pprent during the winter, nd mjor fouling occurred only fter pproximtely 1.5 yers. For ny future evlution of UF membrne performnce, the following re recommended: Striner equipment for use upstrem of the MF or UF equipment should be evluted. The recommended 30 nd 40 mesh bsket striners did not seem dequte in this project. Mximum clening intervls should be estblished nd mintined from the beginning of the study period. In this study, the membrnes were initilly clened only when wrrnted by high TMP vlues; this mode of opertion my hve llowed prticles to become permnently trpped in the membrne mtrix. The intervl cn be incresed s wrrnted by performnce lter. Prticle size distributions should be routinely mesured in both the feed wter nd the filtrte, to ssist in evluting membrne loding nd performnce UF-RO The UF-RO ws successfully operted for pproximtely two yers during this project. During Phse 1, n increse in the differentil pressure suggested deposition of mteril in the chnnels tht connect the RO feed nd concentrte; however, no further deposition occurred in Phses 2 or 3. Performnce ws ffected by wter temperture, with incresing temperture cusing lower feed pressures nd greter slt pssge. The utopsy results of the Phse 1 membrnes indicted both fouling nd chlorine degrdtion of the membrnes. The fouling reduced the flux through the membrnes, nd the clening conducted fter Phse 1 removed the foulnt(s), thereby incresing both the permebility nd the slt pssge. Consistent with the utopsy, the specific flux incresed fter clening of the pilotscle RO membrnes. The utopsy of the Phse 3 membrnes reveled fouling, but no membrne dmge. Optimiztion of the RO opertions resulted in 40% decrese in the use of sulfuric cid from Phse 1 to Phse 2. In Phse 3, new RO membrnes were used nd opertions were ltered to minimize fouling. The resulting sulfuric cid use ws 16% lower thn in Phse 1. Fouling 57

78 ppered to be controlled, but much longer opertionl time would be needed to ensure tht the optimized opertions in Phse 3 mitigted the longer term or sesonl fouling tht ws observed during Phse MBR The MBR ws successfully operted for 1.5 yers during this project, nd provided good qulity wter for the downstrem RO unit, with the exception of one fouling event. This event ws most likely due to dmged membrne fibers; the ge of the membrnes (nine yers old t the time of the event) my hve been contributing fctor in the dmge. In the third phse, with the newest membrnes vilble from GE, the operting flux of the MBR ws similr to tht of the UF. Some fouling did occur, but in mny cses, the effects were temporry. In some cses, the opertion of the MBR ws ltered to decrese the bckpulse cycle time for short time; this chnge ppered to restore norml opertions. The most intensive fouling occurred in Phse 2, when the flux ws incresed from 10 to 15 gfd, with reltively low MLSS concentrtion, possibly becuse the MLSS ws insufficient to tret the foulnts in the mixed liquor nd/or becuse the membrnes were ner the end of their design life MBR-RO The MBR-RO ws successfully operted for 1.5 yers during this project. The differentil pressure ws constnt for the durtion, with no signs of mteril depositing in the chnnels tht connect the RO feed nd concentrte. Ner the end of Phse 1, n unexpected MBR shutdown resulted in RO system shutdown, nd subsequent increse in feed pressure nd decrese in normlized specific flux, presumbly due to fouling. Clening with sodium hydroxide solution t ph 11.5 restored the membrnes to ner norml opertions. MBR-RO performnce ws ffected by wter temperture, with incresing temperture cusing lower feed pressures nd greter slt pssge. During Phse 2, normlized slt pssge lso incresed fter dmge of the MBR membrnes incresed turbidity in the feed wter nd cused one-month shutdown of the RO system. Bsed on the utopsy results, the membrnes ppered to be both fouled nd dmged during Phse 1. The fouling reduced the flux through the membrnes, nd the clening conducted fter Phse 1 removed the foulnt(s), thereby incresing both the permebility nd the slt pssge. The membrne dmge on the MBR-RO membrne ppered to be less severe thn on the UF- RO membrne, bsed on ppernce nd the increse in slt pssge during the utopsy, nd the increse in flux in the pilot-scle unit fter clening ws lso smller thn for the UF-RO system. Optimiztion of the RO opertions resulted in 95% decrese in the use of sulfuric cid from Phse 1 to Phse 2. In Phse 3, new RO membrnes were used nd opertions were ltered to minimize fouling. The resulting sulfuric cid use ws 53% lower thn in Phse 1. Fouling ppered to be controlled, but much longer opertionl time would be needed to ensure tht the optimized opertions in Phse 3 mitigted the fouling effects tht were observed during the occsionl MBR shutdowns in Phses 1 nd 2. 58

79 5. WATER QUALITY RESULTS: GENERAL PARAMETERS This chpter covers results for the generl wter qulity prmeters, excluding the nitrosmines, 1,4-dioxne, nd Title 22+ smples, which re covered in Chpters 6 nd 7. Tbles 5-1 nd 5-2 present summry of the wter qulity dt for the UF nd MBR trins, respectively. Ech of these nlytes is discussed in more detil in the following sections, which re grouped by removl mechnisms. Section 5.1 discusses compounds removed with solids, Section 5.2 discusses compounds ffected by biologicl ctivity in the MBR, nd Section 5.3 discusses compounds removed only by RO. Section 5.4 covers ph, temperture, nd TSS. For ll grphs in this chpter, the three opertionl phses re divided by dshed verticl lines in the grphs, concentrtion dt re plotted on logrithmic scle unless otherwise noted, percent removls re plotted on liner scle, nd the following shorthnd nottions re used: Sec Eff: secondry effluent, UF-RO: RO unit on the UF trin UF: UF filtrte, UF Removl: removl cross the UF unit, RO (UF): RO permete on the UF trin, RO (UF) Removl: removl by the RO unit lone on the UF trin, UF+RO Removl: removl by the combintion of the UF nd RO units, MBR-RO: RO unit on the MBR trin MBR: MBR permete, MBR Removl: removl cross the MBR unit, RO (MBR): RO permete on the MBR trin, MBR (RO) Removl: removl by the RO unit lone on the MBR trin, nd MBR+RO Removl: removl by the combintion of the MBR nd RO units. For ll nlyses, ech smple with concentrtion below the reporting limit ws conservtively ssigned the reporting limit s concentrtion, e.g., concentrtions < 0.01 mg/l were ssumed to be 0.01 mg/l. Removls could not be clculted ccurtely for smples where the effluent concentrtion ws below the reporting limit. For exmple, concentrtion decrese from 2 mg/l to 1 mg/l would be interpreted s 50% removl on grph or in sttisticl clcultions, but the true removl could be nywhere from %. Becuse these vlues re susceptible to misinterprettion, they were omitted from the sttisticl nlyses nd from the grphs presented in this chpter. Note tht using this method under-predicts removls, becuse the lowest effluent concentrtions (corresponding to the highest removl vlues) were excluded from the nlyses. Sttisticl tests in this chpter were conducted with significnce level of 0.01, i.e., tests with p- vlues <0.01 were interpreted s being sttisticlly significnt. Appendix E contins dditionl wter qulity dt nd nlysis, including tbles with detiled sttistics for ech of the wter qulity prmeters. In ddition, selected prmeters were mesured in AOP experiments; the effects of AOP on these nlytes were minor nd re therefore not included within this chpter, but re insted discussed in Appendix E. In some of these AOP experiments, phrmceuticls, personl cre products, endocrine disrupting compounds, nd other wstewter indictors were lso mesured; these compounds were seldom detected in the RO permete nd re discussed in Appendix E. Finlly, differences in RO performnce over time were observed for most prmeters. Although the differences were sttisticlly significnt, they were generlly too smll to be of prcticl importnce, nd re insted presented in Appendix E; only lrger differences re discussed within this chpter. 59

80 Tble 5-1. Wter Qulity Dt for the UF Trin: Minimum, Medin, nd Mximum Vlues 60 Secondry Effluent* UF Filtrte RO Permete RO Concentrte Prmeter Unit Min Med. Mx Min Med. Mx Min Med. Mx Min Med. Mx Alklinity, Totl mg/l CCO Aluminum μg/l <10 <10 18 <10 < Ammoni mg N/L Brium μg/l <0.5 < Boron mg/l Clcium mg/l < Chloride mg/l , COD, Soluble mg/l COD, Totl mg/l Fluoride mg/l < < Iron mg/l <0.02 <0.02 < Mgnesium mg/l <0.02 <0.02 < Nitrte mg N/L <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 < Nitrite mg N/L < < <0.01 <0.01 < ph Phosphte mg P/L < <0.13 <0.13 < Potssium mg/l Silic mg SiO 2 /L Sodium mg/l ,400 2,530 2,790 Strontium μg/l < ,000 4,820 5,140 Sulfte mg/l <0.50 < ,780 2,270 2,550 TDS mg/l 1,170 1, ,210 1,420 1, ,700 8,830 9,670 TKN mg N/L TOC mg/l <0.5 < TSS mg/l Turbidity NTU < *Minimum, medin, nd mximum vlues were clculted for the phse dtes shown in Section 1.5. Becuse these dtes for the UF nd MBR trins re slightly different, the secondry effluent vlues in Tbles 5-1 nd 5-2 re lso different.

81 Tble 5-2. Wter Qulity Dt for the MBR Trin: Minimum, Medin, nd Mximum Vlues 61 Secondry Effluent* MBR Permete RO Permete RO Concentrte Prmeter Unit Min Med. Mx Min Med. Mx Min Med. Mx Min Med. Mx Alklinity, Totl mg/l CCO < Aluminum μg/l <10 <10 17 <10 <10 < Ammoni mg N/L <1.0 < <1.0 <1.0 < Brium μg/l <0.5 < Boron mg/l Clcium mg/l < Chloride mg/l ,730 2,820 3,060 COD, Soluble mg/l COD, Totl mg/l Fluoride mg/l <0.10 < Iron mg/l <0.02 <0.02 < Mgnesium mg/l <0.02 < Nitrte mg N/L <0.10 <0.10 < < Nitrite mg N/L < < <0.01 <0.01 < ph Phosphte mg P/L < <0.13 <0.13 < Potssium mg/l Silic mg SiO 2 /L Sodium mg/l ,230 2,430 2,520 Strontium μg/l < ,750 4,540 5,370 Sulfte mg/l <0.50 < ,220 1,560 1,740 TDS mg/l 1,170 1,410 1,570 1,280 1,510 1, ,250 8,620 9,210 TKN mg N/L <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 TOC mg/l <0.5 <0.5 < TSS mg/l Turbidity NTU < *Minimum, medin, nd mximum vlues were clculted over ll three phses shown in Section 1.5. Becuse the phse dtes for the UF nd MBR trins re slightly different, the secondry effluent vlues in Tbles 5-1 nd 5-2 re lso different.

82 5.1 COMPOUNDS REMOVED WITH SOLIDS Anlytes tht were removed with solids (turbidity, luminum, iron, nd brium) re discussed in this section. These compounds were removed to similr degree by the UF nd the MBR, which were equipped with membrnes of the sme nominl pore size. TOC ws lso prtilly removed by the UF, but ws ffected by biologicl ctivity nd is discussed in Section Aluminum Aluminum results re presented in Figure 5-1; note tht the concentrtions on the y-xis re on liner scle. Concentrtions were lwys below the trget concentrtion of 50 g/l, even in the secondry effluent. The UF nd MBR generlly removed luminum to below the JWPCP Lb reporting limit of 10 g/l; RO permete concentrtions were lwys below the reporting limit. Due to the low concentrtions, removls could not be ccurtely clculted for ny of the unit processes, nd no comprisons were mde between the two trins or over time. Figure 5-1. Aluminum Concentrtions Aluminum Concentrtion (µg/l) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Brium The brium concentrtions in the secondry effluent incresed sttisticlly significntly from Phse 1 to 2, but were lwys well below the trget of 1,000 g/l (Figure 5-2). Both the UF nd MBR removed pproximtely 10-15% of the brium in the secondry effluent, nd the RO removed it to below reporting limits. Medin removls by the UF nd MBR incresed slightly but significntly, from 8-9% in Phse 1 to 14-15% in Phses 2 nd 3. The reson for the improved removls by the UF nd MBR in Phses 2 nd 3 is unknown; however, the difference hs no prcticl importnce, given the high levels of removl in the RO units. 62

83 () Brium Concentrtion (µg/l) Figure 5-2. Brium Results. () Concentrtions nd (b) Removls (b) 0.1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Brium Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl MBR Removl Iron Figure 5-3 shows the results for iron. Concentrtions typiclly rnged from 0.8 to 2.6 mg/l in the secondry effluent, nd were generlly below the trget of 0.3 mg/l in the UF filtrte nd MBR permete. The performnce of the UF nd MBR were similr to ech other nd reltively constnt over time, with medin removls of 90-95%. RO removed the remining iron to below the reporting limit of 0.02 mg/l. () Iron Concentrtion (mg/l) Figure 5-3. Iron Results. () Concentrtions nd (b) Removls (b) Sec Eff UF RO (UF) MBR RO (MBR) Iron Removl (%) UF Removl MBR Removl /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte -20 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Phosphte Figure 5-4 presents the results for phosphte; note tht the concentrtions on the y-xis of Figure 5-4 re on liner scle. Concentrtions in the secondry effluent rnged from pproximtely 0.2 to 0.9 mg P/L, nd ppered to follow sesonl trend in 2011 nd 2012 but not in 2010, with higher concentrtions during the summer. As result, the secondry, UF, nd MBR effluent concentrtions were significntly lower in Phse 1 thn in Phses 2 or 3. The UF nd MBR removed pproximtely 50% of the phosphte in the wter, nd no significnt differences were observed between the two units. Phosphte ws removed to below reporting limits by the RO units; no trget ws set for effluent phosphte concentrtions. 63

84 () Phosphte (mg P/L) Figure 5-4. Phosphte Results. () Concentrtions nd (b) Removls (b) 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Phosphte Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl MBR Removl Turbidity Turbidity results re presented in Figure 5-5; note tht the concentrtions on the y-xis in Figure 5-5 re on liner scle. Turbidity vlues rnged from pproximtely 1.9 to 5.6 NTU in the secondry effluent, with the verge vlues incresing sttisticlly significntly from Phse 1 to Phse 2, nd gin from Phse 2 to Phse 3. The UF nd MBR lwys removed turbidity to below the trget of 2 NTU. The performnce of the UF nd MBR were similr to ech other nd reltively constnt over time, with medin removls of 95-97%. () Turbidity (NTU) Figure 5-5. Turbidity Results. () Concentrtions nd (b) Removls (b) Sec Eff UF MBR Turbidity Removl (%) UF Removl MBR Removl 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte 5.2 BIOLOGICAL TREAMENT BY THE MBR Biologicl ctivity in the MBR ffected severl constituents in the pilot-scle system: the nitrogen species (mmoni, TKN, nitrte, nd nitrite), lklinity, COD, nd TOC. The MBR ws operted under nitrifying conditions, so mmoni nd TKN were oxidized to nitrte, with nitrite s n intermedite. Alklinity ws consumed during the nitrifiction process, nd TOC nd COD were consumed by biologicl ctivity. 64

85 5.2.1 Ammoni nd TKN Ammoni nd TKN results re presented in Figures 5-6 nd 5-7. Ammoni nd TKN concentrtions in the secondry effluent incresed slightly but sttisticlly significntly, from medin concentrtion of 36 mg N/L mmoni in Phses 1 nd 2 (38 mg N/L TKN), to 40 mg N/L in Phse 3 (42 mg N/L TKN). The UF provided negligible removl of either nlyte, while the MBR generlly reduced concentrtions down to the reporting limit of 1 mg N/L. Ammoni nd TKN removls for MBR-RO re not shown in Figures 5-6b nd 5-7b becuse the concentrtions in the RO effluent were generlly below reporting limits. () Ammoni Concentrtion (mg N/L) Figure 5-6. Ammoni Results. () Concentrtions nd (b) Removls (b) Sec Eff UF RO (UF) MBR RO (MBR) Ammoni Removl (%) UF Removl RO (UF) Removl UF-RO Removl 1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte -20 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte () TKN Concentrtion (mg/l) Figure 5-7. TKN Results. () Concentrtions nd (b) Removls Sec Eff UF RO (UF) MBR RO (MBR) TKN Removl (%) (b) UF Removl RO (UF) Removl UF-RO Removl 1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte -20 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte The performnce of the UF-RO ws significntly worse during Phse 2 (See Appendix E for detils), but the effects were smll: removls were pproximtely 95% for mmoni nd TKN in ll three phses, nd permete concentrtions were generlly between 1.0 nd 2.8 mg N/L, regrdless of temperture. There were no specific effluent trgets for mmoni or TKN, lthough the totl nitrogen trget ws 10 mg N/L. The UF-RO permete (which hd low nitrte nd nitrte concentrtions, s discussed in Sections nd 5.2.3) could meet this limit. The bility of the MBR-RO to meet this limit is discussed in the next section. 65

86 5.2.2 Nitrte Nitrte results re shown in Figure 5-8. Nitrte levels in the secondry effluent, UF filtrte, nd UF-RO permete were consistently below the reporting limit of 0.1 mg N/L. The MBR typiclly nitrified most of the mmoni nitrogen to nitrte. As the medin secondry mmoni levels incresed from 36 mg N/L in Phses 1 nd 2 to 40 mg N/L in Phse 3, medin nitrte levels in the MBR permete incresed from 37 mg N/L during Phses 1 nd 2 to 41 mg N/L during Phse 3. () Nitrte Concentrtion (mg N/L) Figure 5-8. Nitrte Results. () Concentrtions nd (b) Removls (b) 100 Sec Eff 100 UF 98 RO (UF) MBR 94 RO (MBR) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Dte Nitrte Removl (%) RO (MBR) Removl For the RO unit on the MBR trin, permete concentrtions nd removls vried significntly over time. The correltion between temperture nd RO removls cn be seen in Figure 5-9. Nitrte removls in the MBR-RO permete decresed from 96% in the winter to s low s 85% during the wrmer months, nd concentrtions incresed from pproximtely 2 to 5 mg N/L. The observed removls by the RO membrnes during Phse 2 were slightly lower thn expected from the temperture trend, which my reflect chlorine degrdtion of the RO membrnes, s discussed in Section 4.3. Despite the worse performnce in Phse 2, the trget concentrtion of 10 mg N/L totl nitrogen ws chieved. However, the temperture effect ws reltively lrge nd could be n importnt fctor in RO design for some fcilities. Figure 5-9. Temperture Effects on Removl of Nitrte by RO Nitrte Removl (%) Phse 1, MBR-RO Phse 2, MBR-RO Phse 3, MBR-RO Temperture ( C) 66

87 5.2.3 Nitrite Nitrite results re shown in Figure 5-10; note tht the y-xis on Figure 5-10 is on liner scle. Concentrtions in the secondry, UF, nd MBR smples vried from < 0.01 to 0.08 mg N/L, well below the trget of 1 mg/l; due to the low concentrtions, removls cross the UF nd MBR were not clculted. RO removed nitrite to below the reporting limit of 0.01 mg/l. Figure Nitrite Results. Nitrite Concentrtion (mg N/L) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Alklinity Results for totl lklinity re shown in Figure Secondry effluent concentrtions rnged from pproximtely 340 to 400 mg/l s CCO 3, nd incresed slightly but sttisticlly significntly in Phse 3. The UF hd no effect on lklinity, but the MBR decresed lklinity levels by pproximtely 70-75%. This decrese in lklinity corresponded to theoreticl mmoni consumption of 38 mg N/L of mmoni (Tchobnoglous et l., 2003), which mtched the observed decrese in mmoni (Section 5.2.1). The lower lklinity levels in the MBR-RO permete (medin concentrtion < 5 mg/l s CCO 3, compred to 20 mg/l s CCO 3 in the UF- RO permete) reduced the sulfuric cid requirements for the MBR-RO (Section 4.4.2) nd my hve improved the performnce of the AOP, thereby reducing the hydrogen peroxide dose required to meet tretment trgets (Section 6.4.3). Figure Totl Alklinity Results. () Concentrtions nd (b) Removls () (b) Totl Alklinity Concentrtion (mg/l) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Totl Alklinity Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF + RO Removl MBR Removl 67

88 Removls by the UF-RO correlted with temperture (Appendix C), but the effect ws smll: the UF-RO removed pproximtely 95% of the lklinity, nd permete concentrtions were pproximtely 20 mg/l s CCO 3 throughout the study. There ws no trget for the lklinity concentrtion COD Results for totl nd soluble COD in secondry effluent smples re plotted in Figure For the UF trin, the medin soluble COD level ws 8 mg/l (15%) lower thn the totl COD level of 53 mg/l. Filtrtion through the UF ws expected to remove prticulte COD, leving pproximtely 45 mg/l of COD in the UF filtrte. Totl COD results re shown in Figure 5-13; note tht totl COD smples were only collected for the secondry effluent nd MBR permete, nd concentrtions re plotted on liner scle. The totl COD concentrtions in the secondry effluent rnged from 34 to 82 mg/l, nd incresed significntly in Phse 3. The medin concentrtion in the secondry effluent ws pproximtely 55 mg/l in Phses 1, 2, nd 3, nd the MBR removed pproximtely 23 mg/l (40%). Similr to the UF, the MBR ws expected to remove the 8 mg/l of prticulte COD from the secondry effluent. The remining 15 mg/l ws presumbly removed by biologicl ctivity in the rector, indicting tht pproximtely 25% of the totl COD (pproximtely one-third of the soluble COD) in the secondry effluent ws biodegrdble. There ws no trget concentrtion for COD. Figure Comprison of Totl nd Soluble COD Secondry Effluent COD Concentrtion (mg/l) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Totl Soluble () COD Concentrtion (mg/l) Figure Totl COD. () Concentrtions nd (b) Removls (b) 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff MBR COD Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte MBR Removl 68

89 5.2.6 TOC TOC results re shown in Figure Concentrtions in the secondry effluent rnged from pproximtely 13 to 20 mg/l, nd incresed significntly from Phse 1 to Phse 2, nd gin in Phse 3. Approximtely 20% of the TOC in the secondry effluent ws likely ssocited with solids nd filtered out by the UF. The MBR removed n dditionl 20% (totl of 40% removl), due to biologicl ctivity in the rector. The RO units generlly removed TOC down to the reporting limit of 0.5 mg/l, which ws lso the trget concentrtion. However, the UF-RO permete concentrtions were occsionlly greter thn the trget concentrtion of 0.5 mg/l during Phses 1 nd 2; the MBR-RO permete consistently met the TOC trget. () TOC Concentrtion (mg/l) Figure TOC. () Concentrtions nd (b) Removls (b) Sec Eff UF RO (UF) MBR RO (MBR) TOC Removl (%) UF Removl MBR Removl 0.1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte -20 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte 5.3 CONSTITUENTS REMOVED ONLY BY RO This section discusses the nlytes tht were removed only by the RO units. Becuse the UF or MBR ws ineffective for removl of these prmeters, only the RO performnce is discussed in the following sections. The constituents re orgnized in lphbeticl order: boron, clcium, chloride, fluoride, mgnesium, potssium, silic, sodium, strontium, sulfte, nd TDS Boron Boron results re plotted in Figure 5-15; the y-xis on Figure 5-15 is on liner scle. Secondry effluent concentrtions rnged from pproximtely 0.7 to 1.1 mg/l, nd incresed significntly between Phses 1 nd 2. Medin removls by the RO units in the three opertionl phses vried from 17 to 44%, with significntly worse performnce in Phse 2 (Figure 5-16). As shown in Figure 5-16b, removls correlted with temperture, nd decresed from pproximtely 45% t 24 C to 15% t 29 C; concentrtions incresed from s low s 0.4 mg/l in the erly months of 2011 to 0.8 mg/l in the summers of 2011 nd The trget concentrtion for boron ws 0.5 mg/l, nd ws only chieved in Phse 1 for the MBR-RO (operted during the winter months, December 2010 to Mrch 2011). During the winter of , the incresed removls in the colder wether were offset by n increse in boron concentrtions in the RO influent strem. Thus, both temperture nd influent composition impcted the boron concentrtions in the RO permete. 69

90 () Boron Concentrion (mg/l) Figure Boron Results. () Concentrtions nd (b) Removls (b) 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Boron Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl () Boron Removl (%) Figure Boron Removls by RO Alone s Function of () Time nd (b) Temperture (b) RO (UF) Removl RO (MBR) Removl Boron Removl (%) Phse 1, UF-RO Phse 1, MBR-RO Phse 2, UF-RO Phse 2, MBR-RO Phse 3, UF-RO Phse 3, MBR-RO 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture ( C) Boron is notoriously difficult to remove from wter, nd the trget concentrtion of 0.5 mg/l ws exceeded frequently. Meeting the boron trget of 0.5 mg/l my necessitte the use of ion exchnge or RO membrnes tht re specific for boron removl; further reserch on boron removl technologies continues to be conducted (Ferreir et l., 2006; Hill et l., 2010; Dydo et l., 2012). Alterntively, boron source control could be considered, to reduce the levels entering the JWPCP. Boron in the JWPCP effluent likely origintes from lundry nd clening products, nd from industries such s fiberglss mnufcturing, cermic mteril production nd semiconductor mnufcturing Clcium Clcium results re plotted in Figure Secondry effluent concentrtions vried from pproximtely 63 to 82 mg/l, with no significnt differences over time. The RO units on both trins provided medin removls of > 99% in Phses 1, 2, nd 3. RO removls correlted with temperture (Appendix C), but the effect ws smll: permete concentrtions were generlly ner the reporting limit of 0.02 mg/l throughout the study. There ws no trget concentrtion for clcium. 70

91 () Clcium Concentrtion (mg/l) Figure Clcium Results. () Concentrtions nd (b) Removls (b) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Clcium Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl Chloride Chloride results re plotted in Figure Secondry effluent concentrtions rnged from pproximtely 400 to 550 mg/l, nd incresed significntly from Phse 1 to Phse 2. The RO units on both trins provided medin removls of pproximtely 98% cross ll three phses of opertion. RO removls correlted with temperture (Appendix C), but hd no prcticl implictions on wter qulity: permete concentrtions vried between 2 nd 17 mg/l, nd were lwys well below the trget concentrtion of 100 mg/l. () Chloride Concentrtion (mg/l) Figure Chloride Results. () Concentrtions nd (b) Removls (b) 1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Chloride Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl Fluoride Fluoride results re plotted in Figure Secondry effluent concentrtions rnged between pproximtely 0.9 nd 3.0 mg/l, with no difference mong the three phses. The RO units on both trins provided medin removls of 86-91% cross ll three phses of opertion. There ws no sttisticlly significnt difference in performnce mong the three phses, nd removls did not correlte with temperture (Appendix E). Permete concentrtions rnged from 0.1 to 0.4 mg/l, nd were lwys less thn the trget concentrtion of 2 mg/l. 71

92 () Fluoride Concetrtion (mg/l) 10 1 Figure Fluoride Results. () Concentrtions nd (b) Removls (b) 0.1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Fluoride Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl Mgnesium Mgnesium results re plotted in Figure Secondry effluent concentrtions vried from pproximtely 20 to 29 mg/l, with no significnt differences mong the phses. The RO units on both trins provided medin removls of > 99% cross ll three phses of opertion. RO permete concentrtions were generlly below the reporting limit of 0.02 mg/l during ll three phses. Becuse the RO permete levels were low, removls cross the RO were not clculted. There ws no trget concentrtion for mgnesium. () Mgnesium Concentrtion (mg/l) Figure Mgnesium Results. () Concentrtions nd (b) Removls /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) (b) Mgnisium Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl MBR Removl Potssium Potssium results re plotted in Figure Secondry effluent concentrtions vried from pproximtely 19 to 24 mg/l, with smll but sttisticlly significnt increse in verge concentrtions from Phse 2 to Phse 3. The RO units on both trins provided medin removls of 96-98% in Phses 1, 2, nd 3. RO removls correlted with temperture (Appendix C), but the effect ws smll: permete concentrtions rnged from 0.2 to 1.0 mg/l throughout the study. There ws no trget concentrtion for potssium. 72

93 () Potssium Concentrtion (mg/l) Figure Potssium Results. () Concentrtions nd (b) Removls Sec Eff UF RO (UF) MBR RO (MBR) (b) Postssium Removl (%) UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl 0.1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte -20 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Silic Silic results re plotted in Figure Secondry effluent concentrtions vried from pproximtely 22 to 28 mg SiO 2 /L, with no differences cross the three phses. The RO units on both trins provided medin removls of 96-99% cross ll three phses of opertion. RO removls correlted with temperture, but the removls in Phse 2 were lower thn expected from the temperture trend (Figure 5-23), which my reflect chlorine degrdtion of the RO membrnes, s discussed in Section 4.3. The resulting RO permete concentrtions increse from s low 0.13 mg SiO 2 /L t the end of Phse 1, to s high s 1.4 mg SiO 2 /L ner the beginning of Phse 2. There ws no trget concentrtion for silic. () Silic Concentrtion (mg SiO2/L) Figure Silic Results. () Concentrtions nd (b) Removls (b) 0.1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Silic Romovl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl 73

94 () Silic Romovl (%) Figure Silic Removls by RO Alone s Function of () Time nd (b) Temperture (b) RO (UF) Removl RO (MBR) Removl Silic Removl (%) Phse 1, UF-RO Phse 1, MBR-RO Phse 2, UF-RO Phse 2, MBR-RO Phse 3, UF-RO 94 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture ( C) Sodium Sodium results re plotted in Figure Secondry effluent concentrtions vried from pproximtely 340 to 460 mg/l, with no chnges in concentrtions cross the phses. The RO units on both trins provided medin removls of 96-98% in Phses 1, 2, nd 3. RO removls correlted with temperture (Appendix C), but the effect ws smll: permete concentrtions rnged between 5 nd 21 mg/l throughout the study. There ws no trget concentrtion for sodium. () Sodium Concentrtion (mg/l) Figure Sodium Results. () Concentrtions nd (b) Removls /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) (b) Sodium Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF-RO Removl MBR Removl RO (MBR) Removl MBR-RO Removl Strontium Strontium results re plotted in Figure Secondry effluent concentrtions vried from pproximtely 630 to 900 g/l, nd incresed significntly from Phse 1 to Phse 2. The RO units on both trins provided medin removls of > 99% in Phses 1, 2, nd 3. RO removls correlted with temperture (Appendix C), but the effect ws smll: permete concentrtions rnged from < 0.2 to 0.7 g/l throughout the study. There ws no trget concentrtion for strontium. 74

95 () Strontium Concetrtion (µg/l) Figure Strontium Results. () Concentrtions nd (b) Removls (b) 0.1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Strontium Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl Sulfte Sulfte results re plotted in Figure Secondry effluent concentrtions rnged from pproximtely 180 to 280 mg/l, nd incresed significntly from Phse 1 to Phse 2. Medin RO permete concentrtions in both trins were below both the trget concentrtion of 100 mg/l nd the reporting limit of 0.5 mg/l in Phses 1, 2, nd 3. () Sulfte Concentrtion (mg/l) Figure Sulfte Results. () Concentrtions nd (b) Removls (b) 0.1 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff UF RO (UF) MBR RO (MBR) Sulfte Removl (%) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte UF Removl MBR Removl TDS TDS results re plotted in Figure Secondry effluent concentrtions vried from pproximtely 1,100 to 1,600 mg/l, with no consistent differences over time. The RO units on both trins provided medin removls of 96-98% in Phses 1, 2, nd 3. RO removls correlted with temperture (Appendix C), but hd no prcticl implictions on wter qulity. Permete concentrtions vried from 14 to 76 mg/l throughout the study, well below the trget of 450 mg/l. 75

96 () TDS Concetrtion (mg/l) Figure TDS Results. () Concentrtions nd (b) Removls (b) SEC EFF UF-RO Feed RO(MF) MBR-RO Feed RO(MBR) TDS Removl (%) UF Removl RO (UF) Removl UF + RO Removl MBR Removl RO (MBR) Removl MBR + RO Removl 10 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte -20 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte 5.4 OTHER CONSTITUENTS This section discusses severl other constituents: TSS, which ws mesured only in the secondry effluent, nd ph nd temperture (for which removls re meningless) TSS TSS ws mesured in secondry effluent only. Results re presented in Figure 5-28; note tht the concentrtions re on liner scle. TSS vlues were reltively low, indicting good sludge settling in the full-scle JWPCP fcility. Figure TSS Concentrtions TSS Concentrtion (mg/l) Sec Eff 0 7/1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte ph nd Temperture Results for ph nd temperture re plotted in Figure 5-29; note tht the y-xes re on liner scle. The ph ws close to neutrl for the secondry, UF, nd MBR effluents. As described in Chpter 4, sulfuric cid ws dded upstrem of the RO units, nd decresed the ph in the RO permetes to pproximtely 5.5. Becuse this vlue ws lower thn the trget of , the RO permete would likely need to be treted (e.g., with decrbontion nd lime) to rise the ph, s is typicl for AWT systems. 76

97 Figure Results for () ph nd (b) Temperture () (b) ph 8 Sec Eff 7 UF 6 RO (UF) 5 MBR 4 RO (MBR) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Temperture (ºC) /1/10 12/30/10 7/1/11 12/31/11 7/1/12 Dte Sec Eff RO (UF) MBR RO (MBR) In Figure 5-29b, the temperture of the UF filtrte is not included becuse the probe supplied with the unit ws unrelible. The tempertures in the secondry effluent, MBR permete, nd RO permetes were similr nd followed cler sesonl trend, with tempertures > 30 C during the summer months, nd tempertures < 20 C during the winter months. 5.5 SUMMARY In generl, concentrtions of nlytes in the secondry effluent incresed during the study period. The concentrtions of brium, boron, chloride, phosphte, strontium, nd sulfte were significntly lower in Phse 1 thn in Phses 2 or 3. The concentrtions of TOC nd turbidity incresed significntly from Phse 1 to Phse 2, nd gin to Phse 3. Finlly, the concentrtions of TSS, lklinity, mmoni nd TKN, totl nd soluble COD, nd potssium were significntly higher in Phse 3 thn in either Phse 1 or 2. These chnges in secondry effluent qulity my hve contributed to fouling of the UF nd MBR membrnes, s described in Chpter 4. The UF nd MBR removed nlytes tht were ssocited with prticles nd could be filtered out (luminum, brium, iron, phosphte, nd turbidity); the RO then removed the mesured prmeters to below reporting limits. The biologicl ctivity within the MBR converted mmoni nd TKN to nitrte, consumed lklinity, nd further degrded the orgnic mtter (COD nd TOC) in the secondry effluent. Consequently, concentrtions of nitrte incresed cross the MBR, nd concentrtions of mmoni, TKN, lklinity, COD, nd TOC decresed. The RO systems removed 93-97% of the mesured compounds, or removed them to below reporting limits. The RO units removed the other generl wter qulity prmeters by >95%, except fluoride (80% removl) nd boron (15-50% removl). Wter temperture ffected the RO rejection of lmost ll compounds except fluoride; however, the impcts were generlly smll nd did not ffect the bility of the RO to chieve the trget concentrtions. The compounds tht exhibited the lrgest temperture effects were boron nd nitrte. As wter temperture incresed from pproximtely 24 C to 29 C, RO removls decresed from 45% to 15% for boron nd from 96% to 85% for nitrte. Outside of the temperture effect, the RO performnce ws reltively consistent over time; membrne conditions ppered to ffect the removls of silic nd nitrte during Phse 2, but did not impct the bility of the RO units to meet the trget concentrtions. 77

98 Ultimtely, the treted wter from the pilot-scle UF nd MBR trins met the wter qulity trgets for groundwter rechrge, except for TOC, boron, nd ph. TOC concentrtions in the UF-RO permete occsionlly exceeded the 0.5 mg/l trget in Phses 1 nd 2, but consistently met the trget in Phse 3, fter the RO membrnes were replced; concentrtions in the MBR-RO permete consistently chieved the trget throughout the study. Boron ws present in the RO permetes of both trins t concentrtions s high s 0.8 mg/l, which is greter thn the trget of 0.5 mg/l. Boron is difficult to remove; lthough technologies such s ion exchnge could be used, source control should be considered priority to reduce the concentrtions entering the JWPCP. Finlly, dditionl tretment (e.g., with decrbontion nd lime) would likely be necessry to rise the ph of the RO permete before use. 78

99 6. WATER QUALITY RESULTS: NITROSAMINES AND 1,4-DIOXANE This chpter covers results for the seven nlyzed nitrosmine species (NDMA, NDEA, NDPA, NDBA, NMEA, NPIP, nd NPYR) nd 1,4-dioxne. These compounds re discussed seprtely from the generl wter qulity prmeters in Chpter 7, becuse the removl requirements for these compounds typiclly drive the design specifictions for AOP in AWT systems. Becuse the compounds generlly behved similrly to ech other cross ech unit process, the sections in the chpter re orgnized by unit opertion. Section 6.1 discusses the secondry effluent, Section 6.2 discusses the UF tretment trin, Section 6.3 discusses the MBR tretment trin, nd Section 6.4 compres the UF nd MBR tretment trins. The dt in this chpter re presented grphiclly; sttistics for the dt re tbulted in Appendix F. For ll nlyses, smples with concentrtions below the reporting limit were conservtively ssigned the reporting limit s concentrtion, e.g., concentrtions < 2 ng/l were ssumed to be 2 ng/l. In mny cses, the concentrtions or clculted removls for given compound vried widely. To void hving n extreme point skew the reported vlues, the following nlyses generlly use medin vlues, rther thn verge vlues, except where noted. Finlly, the significnce level for ll sttisticl tests ws set t 0.01, i.e., tests with p-vlues <0.01 were interpreted s being sttisticlly significnt. 6.1 JWPCP SECONDARY EFFLUENT Figure 6-1 plots the medin concentrtions of the seven nitrosmine species nd 1,4-dioxne in the secondry effluent. The error brs represent the minimum nd mximum observed vlues. As cn be seen in Figure 6-1, the concentrtions vried widely for some compounds. NDPA concentrtions decresed from thousnds of ng/l in Phses 1 nd 2, to below the reporting limit in Phse 3. Similrly, NMEA nd NPYR concentrtions were in the tens of ng/l in Phse 1, but decresed to generlly below the reporting limit in Phses 2 nd 3. These vritions likely reflect chnges in the industril composition of the wstewter entering the JWPCP. Figure 6-1. Medin Concentrtions of Nitrosmines nd 1,4-Dioxne in Secondry Effluent. Concentrtions in ng/l, except for 1,4-Dioxne, which hs units of g/l. Secondry Effluent Concentrtion Phse 1 Phse 2 Phse NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne 79

100 6.2 UF TREATMENT TRAIN UF Results Figure 6-2 shows the medin concentrtions in the UF filtrte, nd Figure 6-3 shows the removls by the UF. Removls were clculted for secondry nd UF effluent smples tht were pired (tken on the sme dy), nd t-test ws pplied to the vlues to determine whether the UF provided significnt removl. Note tht no UF smples were tken during Phse 2 for ny compound, or in Phse 3 for 1,4-dioxne, so those concentrtions nd removls re not plotted. In ddition, ccurte removls could not clculted for NDPA, NMEA, nd NPYR in Phse 3, becuse mny smples hd UF filtrte concentrtions below the reporting limit. Figure 6-2. Medin Concentrtions of Nitrosmines nd 1,4-Dioxne in UF Filtrte. Concentrtions in ng/l, except for 1,4-Dioxne, which hs units of g/l. UF Filtrte Concentrtion Phse 1 Phse 3 NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne Figure 6-3. Medin Removl of Nitrosmines nd 1,4-Dioxne by UF. 100 UF Medin Removl (%) Phse 1 Phse 3 NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne 80

101 The UF did not chnge the concentrtion of most of the compounds significntly. However, NDEA concentrtions incresed significntly in both Phses 1 nd 3, NMEA concentrtions incresed significntly in Phse 1, nd NDMA concentrtions incresed significntly during Phse 3. Formtion of these compounds my be due to the ddition of chlorine upstrem of the UF unit. Chlormines (formed from the rection of chlorine nd mmoni) re known to form NDMA in the presence of precursor compounds (Mitch nd Sedlk, 2004), nd chlorine hs been shown to form NDEA nd NMEA in the presence of diethylmine nd mmoni (Andrzejewski et l., 2005) RO Results Figure 6-4 shows medin concentrtions in the RO permete, nd Figure 6-5 shows medin removls by the RO lone nd the combintion of the UF nd RO. Percent removls were clculted for pired smples (tken on the sme dy), nd were used in t-test to determine whether the RO lone or the combintion of UF nd RO provided significnt removl. Removls were clculted only when both the influent nd effluent smples were tken (i.e., UF filtrte nd RO permete smples for removl by RO lone, or secondry effluent nd RO permete smples for removl by combined UF nd RO), nd when the RO permete concentrtions were bove reporting limits. Given these constrints, removls cross the RO lone were clculted for NDMA nd NDEA during Phses 1 nd 3, nd for NDPA during Phse 1. For the combined UF-RO, removls were clculted for NDMA nd NDEA during ll three phses, for NDPA during Phses 1 nd 2, nd for 1,4-dioxne during Phse 2. RO lone nd the combintion of UF nd RO provided sttisticlly significnt removl of ll compounds. Removls generlly incresed with incresing moleculr mss, with NDMA being the smllest molecule nd NDPA being the lrgest. NDMA is known to be poorly removed by RO membrnes (Steinle-Drling et l., 2007). Figure 6-4. Medin Concentrtions of Nitrosmines nd 1,4-Dioxne in UF-RO Permete. Concentrtions in ng/l, except for 1,4-Dioxne, which hs units of g/l. RO Permete Concentrtion, UF Trin Phse 1 Phse 2 Phse 3 NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne 81

102 Figure 6-5. Removl of Nitrosmines nd 1,4-Dioxne by () RO Alone nd (b) Combined UF nd RO. () RO Medin Removl, UF Trin (%) Phse 1 Phse 3 NDMA NDEA NDPA (b) UF+RO Medin Removl (%) Phse 1 Phse 2 Phse 3 NDMA NDEA NDPA 1,4- Dioxne As shown in Figure 6-4, the medin concentrtions of NDBA, NMEA, NPIP, nd NPYR were lwys below the trget levels (provided in Section 3.5), nd generlly below the reporting limit of 2 ng/l in Phses 1, 2, nd 3. NDMA nd NDEA concentrtions were consistently bove the CDPH notifiction level of 10 ng/l. The concentrtions of NDPA nd 1,4-dioxne were occsionlly bove their trgets (10 ng/l nd 1 g/l, respectively), prticulrly during Phse 2. The tretment of these four compounds by dvnced oxidtion is discussed in Section With respect to performnce over time, removls by the combintion of UF nd RO were significntly lower during Phse 2 for NDMA, NDEA, nd NDPA. In ddition, RO permete concentrtions of NDEA, NDPA, nd 1,4-dioxne were significntly higher in Phse 2. The poorer performnce during Phse 2 my be due to fctors such s chlorine degrdtion of the membrnes nd higher verge tempertures during Phse 2. Chlorine degrdtion of the membrnes ws observed during the membrne utopsy (Section 4.3), nd ws exposed fter the deep clening tht ws performed between Phses 1 nd 2. The effect of temperture on RO rejection could not be evluted, due to the limited number of UF filtrte smples. However, temperture effects were observed for NDMA nd NDEA cross the MBR-RO membrnes (Section 6.3.2), nd for mny of the generl wter qulity prmeters (Chpter 5). This effect hs been documented previously (Kim et l., 2009), nd ws ttributed to compounds diffusing more rpidly through the RO membrnes t higher tempertures, thereby incresing their concentrtions in the RO permete AOP Results The following sections provide more detils on the experiments conducted with UV nd hydrogen peroxide during Phse 1; AOP experiments were not conducted during Phses 2 or 3. Note tht throughout this section, RO permete is referred to s the influent for the AOP system. Also, the EED vlues in this study re specific to the tested rector nd should not be pplied to other systems. The objectives of the AOP testing were to meet the trget concentrtions, nd to chrcterize the effects of UV EED nd hydrogen peroxide on the removl of compounds of interest. Tble 6-1 lists the four compounds of interest for the AOP experiments. These were the only compounds tht either exceeded the trget concentrtions in the RO permete or hd removl requirements specified by CDPH. 82

103 Tble 6-1. CDPH Tretment Requirements: UF Trin Units 1,4-Dioxne NDMA NDEA NDPA Notifiction Level (NL) ng/l 1, Mx. Observed Conc., RO Permete ng/l 1, Log Removl Required to Meet NL Log Removl Required by DGRR * - - Controlling Log Removl *The 1.2-log removl requirement ws removed in the 2011 CDPH DGRR but ws kept s trget for this project. For 1,4-dioxne, the tretment gols were n effluent concentrtion less thn 1 g/l nd 0.5-log removl. Bsed on the concentrtions in the UF-RO permete, the 0.5-log requirement ws more difficult to meet, nd ws used s the trget for this project. Becuse the nturl concentrtions were too low to mesure 0.5-log removl, 1,4-dioxne ws spiked t concentrtions of 4 to 20 g/l into the UV influent (RO permete) for the AOP experiments. For NDMA, the tretment gols were n effluent concentrtion less thn 10 ng/l nd 1.2-log removl. Bsed on the mximum concentrtion mesured in the UF-RO permete, the 10 ng/l effluent concentrtion ws more difficult to meet. Nturl NDMA concentrtions were used in most experiments, lthough NDMA ws spiked t concentrtions up to 1,400 ng/l in few initil experiments. Becuse the influent NDMA concentrtions were not controlled, they vried for ech combintion of EED nd hydrogen peroxide dose, nd cused similr vritions in the effluent concentrtions. As result, log removl ws more relible method for compring doses. Bsed on the mximum observed concentrtion nd the notifiction level, log removl of 1.9 ws chosen s the trget for these AOP experiments. Note tht if NDMA were concentrtions decresed (e.g., through source control), lower trget log removl could be used, potentilly reducing the required size nd cost of the AOP system. For NDEA nd NDPA, the tretment gol ws n effluent concentrtion less thn 10 ng/l; there were no log removl requirements. Nturl NDEA nd NDPA concentrtions were used in ll experiments. Due to the uncontrolled influent concentrtions, log removl ws more relible effluent concentrtions in compring UV/hydrogen peroxide doses. Bsed on the mximum observed concentrtions in the UF-RO permete nd the notifiction levels, log removls of 1.4 nd 0.8 were chosen s the trgets for NDEA nd NDPA, respectively. Similr to NDMA, if source control were implemented nd the AOP influent concentrtions decresed, lower trget log removl could be used, potentilly reducing the required size nd cost of the AOP system Removl of 1,4-Dioxne Figure 6-6 shows the effects of UV EED nd hydrogen peroxide dose on the removl of 1,4- dioxne. UV lone (no hydrogen peroxide) removed some 1,4-dioxne, s shown in Figure 6-6. This result ws unexpected, becuse literture indictes tht 1,4-dioxne is not susceptible to photolysis (Asno et l., 2007); however, UV could form rdicl species from the chlormine residuls present in the wter (Wtts nd Linden, 2007), nd these rdicls my rect with 1,4- dioxne. As seen in Figure 6-6b, hydrogen peroxide lone (no UV) provided no removl of 1,4- dioxne. Removls incresed with incresing UV EED t constnt hydrogen peroxide dose, nd incresed with incresing hydrogen peroxide dose t constnt UV EED. 83

104 Figure 6-6. Effects of () UV EED nd (b) Hydrogen Peroxide Dose on the Removl of 1,4-Dioxne in UF-RO Permete. () 1,4-Dioxne Log Removl No Hydrogen Peroxide 2 mg/l 4 mg/l 6 mg/l 6 mg/l, <RL UV EED (kwh/kgl) (b) 1,4-Dioxne Log Removl No UV UF, 2 kwh/kgl UF, 4 kwh/kgl UF, 4 kwh/kgl, <RL UF, 6 kwh/kgl UF, 6 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) The tretment gol of 0.5-log removl ws met t UV EED of 2 kwh/kgl nd hydrogen peroxide dose of pproximtely 4-6 mg/l, but could lso be met t UV EED of 6 kwh/kgl nd hydrogen peroxide dose of pproximtely 2 mg/l Removl of Nitrosmines Figure 6-7 shows the effects of UV EED nd hydrogen peroxide dose on the removl of NDMA. Removl incresed with incresing EED, but hydrogen peroxide dose hd no effect. The tretment gol of 1.9-log removl ws chieved t UV EED of pproximtely 4 kwh/kgl. Figures 6-8 nd 6-9 show the effects of UV EED nd hydrogen peroxide dose on the removl of NDEA nd NDPA, respectively. Hydrogen peroxide lone hd no effect, but t fixed UV EED, incresing hydrogen peroxide dose incresed removls. At fixed hydrogen peroxide dose, incresing UV EED incresed removls. The NDEA trget removl of 1.4-log ws not met t ny of the tested doses. The NDPA trget removl of 0.8-log ws met t UV EED of 4 kwh/kgl nd hydrogen peroxide dose of 6 mg/l, but could lso be met t UV EED of 6 kwh/kgl nd hydrogen peroxide dose of pproximtely 4 mg/l. () NDMA Log Removl Figure 6-7. Effects of () UV EED nd (b) Hydrogen Peroxide Dose on the Removl of NDMA in UF-RO Permete UV EED (kwh/kgl) No peroxide No peroxide, <RL 2 mg/l 2 mg/l, <RL 4 mg/l 4 mg/l, <RL 6 mg/l (b) NDMA Log Removl No UV 2 kwh/kgl 2 kwh/kgl, <RL 4 kwh/kgl 4 kwh/kgl, <RL 6 kwh/kgl 6 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) 84

105 () NDEA Log Removl Figure 6-8. Effects of () UV EED nd (b) Hydrogen Peroxide Dose on the Removl of NDEA in UF-RO Permete. No peroxide 2 mg/l 4 mg/l 6 mg/l 6 mg/l, <RL (b) NDEA Log Removl No UV 2 kwh/kgl 4 kwh/kgl 4 kwh/kgl, < RL 6 kwh/kgl 6 kwh/kgl, < RL UV EED (kwh/kgl) Added Hydrogen Peroxide Dose (mg/l) () NDPA Log Removl Figure 6-9. Effects of () UV EED nd (b) Hydrogen Peroxide Dose on the Removl of NDPA in UF-RO Permete. No peroxide No peroxide, < RL 2 mg/l 4 mg/l 4 mg/l, < RL 6 mg/l 6 mg/l, <RL (b) NDPA Log Removl No UV 2 kwh/kgl 4 kwh/kgl 4 kwh/kgl, <RL 6 kwh/kgl 6 kwh/kgl, <RL UV EED (kwh/kgl) Added Hydrogen Peroxide Dose (mg/l) Of the three detected nitrosmines, NDMA ws the most susceptible to UV. An EED of 6 kwh/kgl provided pproximtely 2.3-log removl of NDMA, followed by NDEA with pproximtely 0.6-log removl, then NDPA with pproximtely 0.2-log removl. For the combintion of UV nd hydrogen peroxide, NDMA continued to be the most esily removed; it ws difficult to observe differences between NDEA nd NDPA removl, becuse mny NDPA smples were below the reporting limit fter AOP tretment. Tble 6-2 provides the estimted hydrogen peroxide doses required to meet the trgets for ech of the compounds. The 0.5-log removl requirement for 1,4-dioxne ws met t ll three tested UV EEDs, with the required hydrogen peroxide decresing s the EED incresed. The trget NDMA removl of 1.9-log ws met t EED vlues of 4 nd 6 kwh/kgl; no hydrogen peroxide ws necessry. The trget NDPA removl of 0.8-log ws met t n EED vlue of 4 kwh/kgl in combintion with 6 mg/l of hydrogen peroxide, or 6 kwh/kgl with 4 mg/l of hydrogen peroxide. Note tht the log removl trget ws bsed on the mximum observed concentrtion in the UF-RO permete nd the Notifiction Levels set by CPDH for drinking wter wells. If the removl trget were insted bsed on the 90 th percentile vlue of 45 ng/l, the CDPH notifiction level could be 85

106 met t doses similr to those required for 1,4-dioxne. If the removl trget were bsed on the medin vlue of 8 ng/l, no AOP tretment would be required. The trget NDEA removl of 1.4-log ws not met t the tested UV EED vlues nd hydrogen peroxide doses. If the removl trget were insted bsed on the 90 th percentile vlue of 180 ng/l, the CDPH notifiction level might be met t UV EED vlues of 6 kwh/kgl in combintion with hydrogen peroxide dose of 6 mg/l. If the removl trget were bsed on the medin vlue of 60 ng/l, the CDPH notifiction level could be met t UV EED vlues of 4 kwh/kgl in combintion with pproximtely 3 mg/l of hydrogen peroxide, or 6 kwh/kgl in combintion with 2 mg/l of hydrogen peroxide. Reducing the influent concentrtions (e.g., through source control) would provide the sme benefit of reducing the doses required to meet the tretment trget. Tble 6-2. Approximte Hydrogen Peroxide Doses (mg/l) Required to Meet Tretment Gols: UF Trin UV EED (kwh/kgl) Compound ,4-dioxne 4-6 ~3 2 NDMA x 0 0 NDEA x x x NDPA x 6 4 x: Did not meet tretment gols t tested hydrogen peroxide doses. 6.3 MBR TREATMENT TRAIN MBR Results Figure 6-10 shows the medin concentrtions in the MBR permete, nd Figure 6-11 shows the removls by the MBR. Removls were clculted for secondry nd MBR effluent smples tht were pired (tken on the sme dy), nd t-test ws pplied to the vlues to determine whether the MBR provided significnt removl, to significnce level of Accurte removl vlues could not clculted for NDPA in Phse 3, nd NMEA nd NPYR in Phses 2 nd 3, becuse MBR permete concentrtions were below the reporting limit. The MBR ffected ll detected compounds except for 1,4-dioxne; the fct tht severl nitrosmines were removed by the MBR but not the UF suggests biologicl ctivity or sorption to the biologicl solids in the MBR. NDPA, NPIP, nd NPYR were significntly removed in ll opertionl phses in which they were mesured. Medin NDPA removls were >90%, while medin NPIP removls vried from 57 to 86%, nd the medin NPYR removl in Phse 1 ws 67%. Removls of NDMA nd NDBA were lower, nd removls were not consistently significnt. Medin NDMA removls vried from 9 to 29% nd were significnt in Phses 2 nd 3, nd medin NDBA removls vried from 25 to 63% nd were significnt in Phses 1 nd 2. These results re consistent with literture reports tht these nitrosmines cn be biodegrded under erobic conditions (Drewes et l., 2006; Kruss et l., 2009). 86

107 Figure Medin Concentrtions of Nitrosmines nd 1,4-Dioxne in MBR Permete. Concentrtions in ng/l, except for 1,4-Dioxne, which hs units of g/l. MBR Permete Concentrtion Phse 1 Phse 2 Phse 3 NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne Figure Medin Removls of Nitrosmines nd 1,4-Dioxne by the MBR. 100 MBR Medin Removl (%) Phse 1 Phse 2 Phse 3 NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne NDEA concentrtions incresed significntly cross the MBR, by pproximtely %. Becuse the MBR permete smples were tken upstrem of ny chlorine ddition, this increse in concentrtions cnnot be ttributed to chlorine. NDEA could be formed by the rection of precursor compounds with nitrte generted during the nitrifiction process; bcteri such s E. coli, Enterococci, clostridi, bcteriodes nd bijidobcteri hve been shown to ctlyze the formtion of nitrosmines in the presence of secondry mines, with nitrte reduction to nitrite s the first step (Foremn nd Goodhed, 1975). However, further study is needed to identify the cuse(s) of the increses in NDEA concentrtions cross the MBR. 87

108 6.3.2 RO Results Figure 6-12 shows medin concentrtions in the RO permete, nd Figure 6-13 shows medin removls by the RO lone nd the combintion of the MBR nd RO. Percent removls were clculted for pired smples (tken on the sme dy), nd were used in t-test to determine whether the RO lone or the combintion of MBR nd RO provided significnt removl. Removls were clculted only when both influent nd effluent smples were tken, nd when the RO permete concentrtions were bove reporting limits. Given these constrints, removls were clculted for NDMA nd NDEA during ll three phses, nd for 1,4-dioxne during Phse 2. Figure Medin Concentrtions of Nitrosmines nd 1,4-Dioxne in MBR-RO Permete. Concentrtions in ng/l, except for 1,4-Dioxne, which hs units of g/l. RO Permete Concentrtion, MBR Trin Phse 1 Phse 2 Phse 3 NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne Figure Removl of Nitrosmines nd 1,4-Dioxne by () RO Alone nd (b) the Combintion of MBR nd RO. () (b) RO (MBR) Medin Removl (%) Phse 1 Phse 2 Phse 3 NDMA NDEA 1,4- Dioxne MBR+RO Medin Removl (%) Phse 1 Phse 2 Phse 3 NDMA NDEA 1,4- Dioxne 88

109 As shown in Figure 6-12, the medin concentrtions of NDPA, NDBA, NMEA, NPIP, nd NPYR were generlly below the trget levels (provided in Section 3.5) nd the reporting limit of 2 ng/l in Phses 1, 2, nd 3. Concentrtions of NDMA nd NDEA were consistently bove the CDPH notifiction level of 10 ng/l, nd 1,4-dioxne concentrtions were occsionlly bove the trget of 1 g/l during Phse 2. Tretment of these three compounds by dvnced oxidtion is discussed in Section In lmost ll cses, removl ws sttisticlly significnt for RO lone nd the combintion of MBR nd RO. The only exception ws NDEA, with the combintion of MBR nd RO during Phses 2 nd 3, due to the formtion of NDEA cross the MBR. As with the UF-RO, the MBR- RO removed NDEA better thn NDMA. With respect to performnce over time, removls by the combintion of MBR nd RO were significntly lower during Phse 2 for NDMA nd NDEA. Removl of 1,4-dioxne could not be compred over time, becuse the RO permete concentrtions in Phses 1 nd 3 were below the reporting limit; however comprison of the concentrtions indictes tht 1,4-dioxne levels were significntly higher in Phse 2. The poorer performnce during Phse 2 my be due to fctors such s chlorine degrdtion of the membrnes nd higher verge tempertures during Phse 2. Chlorine degrdtion of the membrnes ws observed during the membrne utopsy (Section 4.3), nd ws exposed fter the deep clening tht ws performed between Phses 1 nd 2. Temperture effects were observed for NDMA (Figure 6-14) nd NDEA (Figure 6-14b), s well s mny of the generl wter qulity prmeters (Chpter 5 nd Appendix E). This effect hs been documented previously (Kim et l., 2009), nd ws ttributed to compounds diffusing more rpidly through the RO membrnes t higher tempertures, thereby incresing their concentrtions in the RO permete. Figure Effect of Temperture on RO Removls of () NDMA nd (b) NDEA. () (b) NDMA Removl (%) Phse 1, MBR-RO Phse 2, MBR-RO Phse 3, MBR-RO Temperture ( C) NDEA Removl (%) Phse 1, MBR-RO 65 Phse 2, MBR-RO Phse 3, MBR-RO Temperture ( C) AOP Results The following sections provide more detils on the experiments conducted with UV nd hydrogen peroxide during Phse 1; AOP experiments were not conducted during Phses 2 or 3. Note tht throughout this section, RO permete is referred to s the influent for the AOP system. Also, the EED vlues in this study re specific to the tested rector nd should not be pplied to other systems. 89

110 The objectives of the AOP testing were to meet the trget concentrtions, nd to chrcterize the effects of UV EED nd hydrogen peroxide on the removl of compounds of interest. Tble 6-3 lists the three compounds of interest for the AOP experiments. These were the only compounds in the RO permete tht either exceeded the trget concentrtions or hd removl requirements specified by CDPH. The trget log removls were similr to those set for the AOP experiments on the UF trin; see Section for detils on the explntion of the trget removls. Tble 6-3. CDPH Tretment Requirements: MBR Trin Units 1,4-Dioxne NDMA NDEA Notifiction Level (NL) ng/l 1, Mx. Observed Conc., RO Permete ng/l 1, Log Removl Required to Meet NL Log Removl Required by DGRR * - Controlling Log Removl *The 1.2-log removl requirement ws removed in the 2011 CDPH DGRR but ws kept s trget for this project Removl of 1,4-Dioxne Figure 6-15 shows the effects of UV EED nd hydrogen peroxide dose on the removl of 1,4- dioxne. UV lone (no hydrogen peroxide) removed some 1,4-dioxne, s shown in Figure This result ws unexpected, becuse literture indictes tht 1,4-dioxne is not susceptible to photolysis (Asno et l., 2007); however, UV could form rdicl species from the chlormine residuls present in the wter (Wtts nd Linden, 2007), nd these rdicls my rect with 1,4- dioxne. As seen in Figure 6-15b, hydrogen peroxide lone (no UV) provided no removl of 1,4- dioxne. Removls incresed with incresing UV EED t constnt hydrogen peroxide dose, nd with incresing hydrogen peroxide dose t constnt UV EED. The tretment gol of 0.5-log removl ws met t UV EED of 2 kwh/kgl nd hydrogen peroxide dose of pproximtely 4 mg/l, but could lso be met t UV EED of 4 kwh/kgl nd hydrogen peroxide dose of pproximtely 2 mg/l. () 1,4-Dioxne Log Removl Figure Effects of () UV EED nd (b) Hydrogen Peroxide Dose on the Removl of 1,4-Dioxne in MBR-RO Permete. No peroxide 2 mg/l 4 mg/l 6 mg/l 6 mg/l, <RL UV EED (kwh/kgl) (b) 1,4-Dioxne Log Removl No UV 2 kwh/kgl 4 kwh/kgl 4 kwh/kgl, <RL 6 kwh/kgl 6 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) 90

111 Removl of Nitrosmines Figures 6-16 nd 6-17 show the effects of UV EED nd hydrogen peroxide dose on the removl of NDMA nd NDEA, respectively. NDMA removl incresed with incresing EED, but hydrogen peroxide dose hd no effect. The NDMA tretment gol of 1.9-log removl ws chieved t UV EED of 4 kwh/kgl. () NDMA Log Removl Figure Effects of () UV EED nd (b) Hydrogen Peroxide Dose on the Removl of NDMA in MBR-RO Permete UV EED (kwh/kgl) No peroxide No peroxide, <RL 2 mg/l 2 mg/l, <RL 4 mg/l 4 mg/l, <RL 6 mg/l 6 mg/l, <RL (b) NDMA Log Removl No UV 2 kwh/kgl 2 kwh/kgl, <RL 4 kwh/kgl 4 kwh/kgl, <RL 6 kwh/kgl 6 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) () NDEA Log Removl Figure Effects of () UV EED nd (b) Hydrogen Peroxide Dose on the Removl of NDEA in MBR-RO Permete. No peroxide 2 mg/l 4 mg/l 6 mg/l (b) NDEA Log Removl No UV 2 kwh/kgl 4 kwh/kgl 6 kwh/kgl UV EED (kwh/kgl) Added Hydrogen Peroxide Dose (mg/l) For NDEA, hydrogen peroxide lone hd no effect, but t fixed UV EED, incresing hydrogen peroxide dose incresed removls. At fixed hydrogen peroxide dose, incresing UV EED incresed removls. The NDEA trget removl of 1.7-log ws inconsistently chieved t the highest tested doses of 6 kwh/kgl nd 6 mg/l of hydrogen peroxide. NDMA ws more susceptible thn NDEA to tretment by UV lone, or by the combintion of UV nd hydrogen peroxide. For exmple, n EED of 6 kwh/kgl provided pproximtely 2.3- log removl of NDMA, but n EED of 6 kwh/kgl in combintion with hydrogen peroxide doses of 0-6 mg/l provided only 0.5 to 1.7-log removl of NDEA. 91

112 Tble 6-4 provides the estimted hydrogen peroxide doses required to meet the trgets for ech of the compounds. The 0.5-log removl requirement for 1,4-dioxne ws met t ll three tested UV EEDs, with the required hydrogen peroxide decresing s the EED incresed. The trget NDMA removl of 1.9-log ws met t EEDs of 4 nd 6 kwh/kgl; hydrogen peroxide ws not needed. The trget NDEA removl of 1.7-log ws inconsistently chieved t the highest tested doses of 6 kwh/kgl nd 6 mg/l of hydrogen peroxide. Note tht the log removl trget ws bsed on the mximum observed concentrtion in the MBR-RO permete nd the Notifiction Levels set by CPDH for drinking wter wells. If the removl trget were insted bsed on the 90 th percentile vlue of 250 ng/l, the CDPH notifiction level might be consistently chieved t the highest doses tested. If the removl trget were bsed on the medin vlue of 80 ng/l, the CDPH notifiction level would be met t UV EED of 4 kwh/kgl in combintion with 6 mg/l of hydrogen peroxide, or 6 kwh/kgl in combintion with 4 mg/l of hydrogen peroxide. Reducing the influent concentrtions (e.g., through source control) would provide the sme benefit of reducing the doses required to meet the tretment trget. Tble 6-4. Approximte Hydrogen Peroxide Doses (mg/l) Required to Meet Tretment Gols: MBR Trin UV EED (kwh/kgl) Compound ,4-dioxne ~4 2 < 2 NDMA x 0 0 NDEA x x x x: Did not meet tretment gols t tested hydrogen peroxide doses Comprison of Low Pressure (LP) nd Medium Pressure (MP) UV During the Title 22+ events in Phse 3, smples were tken cross the MBR trin for nitrosmines nd 1,4-dioxne. Most of the dt from these events re included in the nlysis in the previous sections; however, the AOP testing ws conducted with different UV rector, nd the results re discussed seprtely in this section. The Title 22+ AOP tests in Phse 3 used Clgon Ryox btch UV rector to compre LP nd MP UV. Both smples were dosed with 4 mg/l of hydrogen peroxide. LP UV ws dosed t 0.9 kwh/kgl nd MP UV ws dosed t 1.5 kwh/kgl. Note tht these EEDs re rector-specific nd do not pply to other rectors; however, the results cn be compred ginst ech other, becuse both lmps were used in the sme rector. On the two Title 22+ smpling dys in Phse 3, only NDMA nd NDEA were detected in the MBR-RO permete; ll other nitrosmines nd 1,4-dioxne were t concentrtions below reporting limits. Results for NDMA nd NDEA re summrized in Tble 6-5. The NDMA trget concentrtion of 10 ng/l ws chieved with the LP lmp on both dys, but not with the MP lmp. Consistent with the results from the Trojn LP UV rectors, NDEA ws more difficult to remove, nd the NDEA trget concentrtion of 10 ng/l ws not chieved with either lmp. The LP lmp provided cler benefit over the MP lmp, with better removl of both NDMA nd NDEA t lower EED vlues (i.e., lower energy use). 92

113 Tble 6-5. Comprison of LP nd MP UV for Tretment of NDMA nd NDEA Compound Effluent UV EED (kwh/kgl) Conc. (ng/l) 5/15/2012 5/22/2012 Log Conc. Removl (ng/l) Log Removl NDMA MBR-RO LP MP NDEA MBR-RO LP MP COMPARISON OF THE UF AND MBR TRAINS This section compres the UF nd MBR trins for tretment of nitrosmines nd 1,4-dioxne. Section compres the UF nd MBR, Section compres the RO units on the two trins, nd Section compres AOP on the two trins Comprison of the UF nd MBR Figure 6-18 compres the concentrtions of the nitrosmines nd 1,4-dioxne in the UF filtrte nd MBR permete. Figure 6-19 compres the medin removls cross the UF nd MBR; error brs represent the minimum nd mximum observed removls. Concentrtions were compred for Phses 1 nd 3, becuse no UF smples were tken during Phse 2. Removls were compred only where vlid vlues could be clculted for both the UF nd MBR; see Sections nd for detils on the determintion of vlid removls. Figure Comprison of UF nd MBR Effluents. Concentrtions in ng/l, except for 1,4-Dioxne, which hs units of g/l. UF or MBR Effluent Concentrtions Phse 1, UF Trin Phse 1, MBR Trin Phse 3, UF Trin Phse 3, MBR Trin 0.1 NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne 93

114 Figure Comprison of Medin Removls of Nitrosmines nd 1,4-Dioxne by UF nd MBR. Medin Removls By UF or MBR (%) Phse 1, UF Trin Phse 1, MBR Trin Phse 3, UF Trin Phse 3, MBR Trin NDMA NDEA NDPA NDBA NPIP NPYR 1,4- Dioxne The MBR removed significntly more NDPA, NPIP, nd NPYR thn the UF for ll compred opertionl phses. Medin concentrtions of these three compounds were lso lower in the MBR permete thn in the UF filtrte, though the differences were significnt only for NDPA nd NPIP in Phse 1. The medin removl by the MBR ws higher thn by the UF for NDMA nd NDBA, lthough the differences were sttisticlly significnt only in Phse 1 for NDBA nd only in Phse 3 for NDMA. The medin concentrtions in MBR permete were lower thn in the UF filtrte for both compounds, but the differences were not sttisticlly significnt. For NDEA, concentrtions nd percent formtion were higher for the MBR, but the differences were not significnt. Overll, these results indicte tht the MBR provided better tretment of five nitrosmine compounds (NDMA, NDPA, NDBA, NPIP, nd NPYR) thn the UF did. These differences re likely due to the biologicl ctivity under the in the MBR, where erobic degrdtion cn occur. The differences in NDEA concentrtions, lthough not sttisticlly significnt, my reflect differences in the underlying sources of the NDEA. NDEA formtion could be ttributed to the ddition of chlormines for the UF, but not for the MBR; formtion cross the MBR my hve been due to biologicl ctivity, but more reserch is needed to definitively identify the cuse(s) Comprison of the RO Permetes from the UF nd MBR Trins Figure 6-20 compres the concentrtions of the nitrosmines nd 1,4-dioxne in the RO permetes from the UF nd MBR trins. Figure 6-21 compres the medin removls for the two trins, cross the RO units nd the combintion of the UF-RO or MBR-RO; error brs represent the minimum nd mximum observed removls. Removls were compred only where vlid vlues could be clculted for both RO units; see Sections nd for detils on the determintion of vlid removls. 94

115 RO Permete Concentrtions Figure Comprison of RO Permetes from the UF nd MBR Trins For Nitrosmines nd 1,4-Dioxne. Concentrtions in ng/l, except for 1,4-Dioxne, which hs units of g/l Phse 1, UF Trin Phse 1, MBR Trin Phse 2, UF Trin Phse 2, MBR Trin Phse 3, UF Trin Phse 3, MBR Trin NDMA NDEA NDPA NDBA NMEA NPIP NPYR 1,4- Dioxne Figure Comprison of Medin Removls of Nitrosmines nd 1,4-Dioxne on the UF nd MBR Trins by () RO Alone nd (b) the Combintion of UF-RO or MBR-RO. () Medin RO Removls (%) NDMA Phse 1, UF Trin Phse 1, MBR Trin Phse 3, UF Trin Phse 3, MBR Trin NDEA (b) Medin Removls by UF+RO or MBR+RO (%) Phse 1, UF Trin Phse 1, MBR Trin Phse 2, UF Trin Phse 2, MBR Trin Phse 3, UF Trin Phse 3, MBR Trin NDMA NDEA 1,4- Dioxne During Phse 1, NDMA removl by RO ws significntly better on the MBR trin thn on the UF trin, nd MBR-RO permete concentrtions were significntly lower. The cuse of this difference is unknown; however, orgnic fouling could ply role. Literture reports tht fouling by biologicl orgnic mteril cn decrese rejection of NDMA by RO membrnes (Steinle- Drling et l., 2007), nd the membrne utopsy fter Phse 1 indicted tht the RO membrnes on the UF trin were more hevily fouled (Section 4.3). 95

116 NDMA removls by the combintion of MBR nd RO were lso significntly greter thn removls by the combintion of UF nd RO during ll three phses. This result is not surprising, becuse for ll opertionl phses where removls could be clculted, medin removls were greter in the MBR thn in the UF, nd were greter for the RO on the MBR trin thn for the RO on the UF trin. Although the differences were not lwys significnt for ech individul unit, it ppers tht the combintion of units produced sttisticlly observble benefit for the MBR-RO system. There ws no sttisticlly significnt difference between the RO units on the UF nd MBR trins for the removl of NDEA or 1,4-dioxne, nd the medin removls of 1,4-dioxne for the combintion of UF-RO nd MBR-RO were similr (89 nd 86%, respectively). However, the removl of NDEA by the combintion of MBR nd RO ws worse thn by the combintion of UF nd RO during ll three phses, nd the difference ws sttisticlly significnt during Phses 2 nd 3. This result ws likely due to greter production of NDEA cross the MBR thn cross the UF Comprison of the AOP Effluents Figures 6-22 to 6-24 compre the UF-RO or MBR-RO effluents for removl of 1,4-dioxne, NDMA, nd NDEA, respectively, t ech of the tested UV EED vlues. A sttisticl ANOVA test ws performed to determine whether the effluent source (UF-RO or MBR-RO permete) hd significnt effect; concentrtions below reporting limits were not included in the nlysis. The results re summrized t the end of Appendix F For 1,4-dioxne, there ws no removl from either effluent when the UV EED ws zero, nd the effluent source hd no significnt effect. However, when UV ws dosed t 2, 4, or 6 kwh/kgl, removl of 1,4-dioxne ws significntly higher in the MBR-RO effluent. This result is reflected in the fct tht the estimted hydrogen peroxide doses required for tretment were lower for MBR-RO effluent thn for UF-RO effluent. For exmple, t n EED of 4 kwh/kgl, the doses required to chieve the trget 0.5-log removl were ~2 mg/l for MBR-RO effluent vs. ~3 mg/l for UF-RO effluent. For NDMA nd NDEA, there ws lso no removl from either effluent when the UV EED ws zero, nd the effluent source hd no significnt effect. A sttisticlly significnt effect of effluent source ws observed only t n EED of 2 kwh/kgl for NDMA nd 4 kwh/kgl for NDEA. In both cses, removl ws significntly higher in the MBR-RO effluent, similr to 1,4-dioxne. No sttisticlly significnt effect of effluent source ws observed t 6 kwh/kgl, possibly becuse mny of the dt points were below the reporting limit; for these points, the true removl vlue is unknown (e.g., >1-log could be 1.1-log, 4-log, or nother vlue ltogether) nd could not be included in the comprison. Overll, the comprison of the UF-RO nd MBR-RO effluents suggests tht removls my be slightly better in MBR-RO effluent thn in UF-RO effluent. This trend is likely cused by differences in the wter qulity, such s the higher UVT in the MBR-RO effluent (which would llow higher levels of rdition to pss through the effluent), or lower lklinity (which is scvenger for peroxide rdicls). Although the mgnitude of the effect ws only ~0.1 to 0.2-log, these differences could result in hydrogen peroxide doses tht re 1 to 2 mg/l lower for the MBR-RO effluent thn the UF-RO effluent. 96

117 Figure Comprison of UF-RO nd MBR-RO Effluents for Removl of 1,4-Dioxne t UV EED Vlues of () 0, (b) 2, (c) 4, nd (d) 6 kwh/kgl. () (b) 1,4-Dioxne Log Removl MBR, No UV UF, No UV ,4-Dioxne Log Removl MBR, 2 kwh/kgl UF, 2 kwh/kgl Added Hydrogen Peroxide Dose (mg/l) Added Hydrogen Peroxide Dose (mg/l) (c) 1,4-Dioxne Log Removl MBR, 4 kwh/kgl MBR, 4 kwh/kgl, <RL UF, 4 kwh/kgl UF, 4 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) (d) 1,4-Dioxne Log Removl MBR, 6 kwh/kgl MBR, 6 kwh/kgl, <RL UF, 6 kwh/kgl UF, 6 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) 97

118 Figure Comprison of UF-RO nd MBR-RO Effluents for Removl of NDMA t UV EED Vlues of () 0, (b) 2, (c) 4, nd (d) 6 kwh/kgl*. () (b) NDMA Log Removl MBR, No UV UF, No UV NDMA Log Removl MBR, 2 kwh/kgl MBR, 2 kwh/kgl, <RL UF, 2 kwh/kgl UF, 2 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) Added Hydrogen Peroxide Dose (mg/l) (c) NDMA Log Removl MBR, 4 kwh/kgl MBR, 4 kwh/kgl, <RL UF, 4 kwh/kgl UF, 4 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) (d) NDMA Log Removl MBR, 6 kwh/kgl MBR, 6 kwh/kgl, <RL UF, 6 kwh/kgl UF, 6 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) *Note: In Figure 6-23d, there were not enough smples with concentrtions bove the reporting limits to provide regression line. 98

119 Figure Comprison of UF-RO nd MBR-RO Effluents for Removl of NDEA t UV EED Vlues of () 0, (b) 2, (c) 4, nd (d) 6 kwh/kgl. () (b) NDEA Log Removl MBR, No UV UF, No UV NDEA Log Removl MBR, 2 kwh/kgl UF, 2 kwh/kgl Added Hydrogen Peroxide Dose (mg/l) Added Hydrogen Peroxide Dose (mg/l) (c) (d) NDEA Log Removl MBR, 4 kwh/kgl UF, 4 kwh/kgl UF, 4.1 kwh/kgl, <DL NDEA Log Removl MBR, 6 kwh/kgl UF, 6 kwh/kgl UF, 6 kwh/kgl, <RL Added Hydrogen Peroxide Dose (mg/l) Added Hydrogen Peroxide Dose (mg/l) 6.5 SUMMARY In pilot-scle system, the UF hd very little effect on most of the nitrosmines nd 1,4-dioxne. The exception ws NDEA, which incresed in concentrtion cross the UF. The MBR ffected ll compounds except 1,4-dioxne. MBR removls of NDPA, NPIP, nd NPYR were sttisticlly significnt in ll opertionl phses where the MBR influent nd effluent concentrtions were bove reporting limits. NDMA nd NDBA were removed to lesser degree, nd the removls were not consistently significnt. Similr to the UF, the concentrtions of NDEA incresed cross the MBR. Further reserch is needed to determine the cuse(s) of this increse. Overll, the results indicte tht MBR provides better removl of NDMA, NDPA, NDBA, NPIP, nd NPYR thn the UF does. The RO membrnes were effective t removing most of the nitrosmines to below the trget concentrtions. The exceptions were NDMA nd NDEA, with concentrtions consistently bove trget levels, nd NDPA nd 1,4-dioxne, with concentrtions occsionlly bove trget levels. The AOP successfully chieved trget removls of 1,4-dioxne, NDMA, nd NDPA. NDEA trgets bsed on the mximum observed RO permete concentrtions were not chieved t the tested doses; however, the trgets could likely be met by incresing the doses, by reducing the influent concentrtions through source control, nd/or by choosing different influent concentrtion (e.g., the 90 th percentile, rther thn the mximum vlue). 99

120 None of the compounds were ffected by hydrogen peroxide lone. NDMA removl incresed with incresing UV dose, but hydrogen peroxide hd no effect on removl. Removls of NDEA, NDPA, nd 1,4-dioxne incresed with incresing doses of either UV or hydrogen peroxide. Removls were generlly slightly better in the MBR-RO effluent, which could result in lower hydrogen peroxide doses (by 1-2 mg/l) to meet regultory removl requirements. Finlly, the LP lmps provided cler benefit over the MP lmps, with better removl of both NDMA nd NDEA t lower EED vlues (i.e., lower energy use). 100

121 7. WATER QUALITY RESULTS: TITLE 22+ PARAMETERS In this chpter, results from the Title 22+ smpling events re discussed, excluding 1,4-dioxne nd the nitrosmines, which were discussed in Chpter 6. A totl of 291 prmeters were nlyzed for this chpter; full list of prmeters nd their reporting limits is provided in Appendix C. The Title 22+ prmeters were grouped into fourteen ctegories: generl physicl prmeters such s turbidity, generl minerl prmeters such s chloride, trce metls, rdiologicl nlytes, microbes, hormones, industril endocrine-disrupting compounds (EDCs), phrmceuticls nd personl cre products (PPCPs), other wstewter indictors such s cffeine, voltile orgnic compounds, semi-voltile orgnic compounds, crbmte pesticides, Stte Wter Resources Control Bord (SWRCB) surrogtes, nd other chemicls. Throughout this chpter, hormones, EDCs, PPCPs, nd other wstewter indictors re sometimes collectively referred to s trce orgnic constituents. There were totl of six smpling events, which were conducted in three sets: from the UF trin during Phse 1 (Februry 16 nd 23, 2011), from the MBR trin during Phse 1 (Mrch 2 nd 9, 2011), nd from the MBR trin during Phse 3 (My 15 nd 22, 2011). In some cses, prmeters were detected on only one of the two smpling dys in set. Becuse the compounds were inconsistently detected nd the detected concentrtions were generlly very low, ccurte removl vlues could not be clculted. Therefore, the dt for these compounds re not discussed in this chpter. Complete dt for ll detected compounds (including those inconsistently detected) t ll loctions re provided in Appendix G. This chpter is orgnized by smpling loction: secondry effluent (Section 7.1), UF trin (Section 7.2), nd MBR trin (Section 7.3). The two trins re compred in Section 7.4, nd results re summrized in Section 7.5. For the UF nd MBR units, only prmeters whose concentrtions chnged significntly cross the unit re discussed; chnge of > 25% in the verge concentrtion ws considered significnt. In ll tbles in this chpter, denotes n increse nd denotes decrese in concentrtion; if the concentrtion decresed to below reporting limits, > is used. For exmple, decrese in concentrtion from 5 mg/l to < 1 mg/l is decrese of t lest 80% nd would be denoted in tble s > JWPCP SECONDARY EFFLUENT Of the 291 Title 22+ prmeters mesured, 78 were consistently detected in both smples of t lest one set. In the UF trin during Phse 1, 74 prmeters were detected in both smples; 72 prmeters in the MBR trin during Phse 1 were detected in both smples, nd 74 prmeters in the MBR trin during Phse 3 were detected in both smples. These compounds nd their concentrtions re listed in Tbles 7-1 to 7-4. The concentrtions of most nlytes were consistent cross the six dys of smpling. The biggest exception ws the trce orgnic constituents (Tble 7-3), which vried by n order of mgnitude in some cses. For exmple, crbmzepine concentrtions were below the reporting limit of 20 ng/l) in the four Phse 1 smples, but were pproximtely 230 ng/l in the two Phse 3 smples. Octylphenol concentrtions decresed from 588 ng/l on My 15, 2012, to 42 ng/l on My 22, Another exception ws MTBE, which rnged from concentrtion of 17 g/l on Februry 16, 2011, to s low s 0.5 g/l on Mrch 9, The reson for the vribility in the secondry effluent is mostly likely due to vritions in the plnt influent wter qulity. 101

122 Tble 7-1. Title 22+ Anlytes Detected in Secondry Effluent: Generl Prmeters 102 Reporting Phse 1 1 Phse 1 1 Phse 3 1 Ctegory Anlyte Units Limit 2/16/11 2/23/11 3/2/11 3/9/11 5/15/12 5/22/12 Generl Alklinity, Totl mg CCO 3 /L Physicl Ammoni mg N/L Prmeters Apprent Color ACU Cynide mg/l ND Odor t 60ºC TON Orgnic Nitrogen mg N/L ph Surfctnts mg/l Specific Conductnce, 25ºC mho/cm 2 2,700 2,600 2,700 2,600 2,400 2,700 Totl Dissolved Solids mg/l 10 1,400 1,400 1,400 1,400 1,300 1,500 Totl Hrdness s CCO 3 mg/l Totl Orgnic Crbon mg/l Turbidity NTU UV Trnsmittnce (254 nm) % Generl Bromide g/l 5 1,600 1,500 1,600 1,600 1,600 1,600 Minerl Boron, Totl mg/l Prmeters Clcium Totl mg/l Chloride mg/l Fluoride mg/l Mgnesium, Totl mg/l Phosphorus, Totl mg/l Potssium, Totl mg/l Sodium, Totl mg/l Sulfte mg/l The UF trin ws smpled on Februry 16 nd 23, 2011; the MBR trin ws smpled on four dtes: Mrch 2 nd 9, 2011, nd My 15 nd 22, ACU = Apprent color unit; ND = not detected; NTU = nephelometric turbidity unit; TON = threshold odor number.

123 Tble 7-2. Title 22+ Anlytes Detected in Secondry Effluent: Trce Metls, Rdiologicl Anlytes, nd Microbes 103 Reporting Phse 1 1 Phse 1 1 Phse 3 1 Ctegory Anlyte Units Limit 2/16/11 2/23/11 3/2/11 3/9/11 5/15/12 5/22/12 Trce Metls Aluminum, Totl g/l Antimony, Totl g/l Arsenic, Totl g/l Brium, Totl g/l Chromium g/l ND ND 1 Iron, Totl mg/l Mngnese g/l Nickel, Totl g/l Selenium, Totl g/l ND Rdiologicl Gross Bet pci/l Urnium pci/l Microbes Cryptosporidium Oocysts/10L NS 2 NS 2 Girdi Cysts/10L 1 1,680 1,330 1,530 1,920 NS 2 NS 2 Heterotrophic Plte Count cfu/ml 1 >5,700 >5,700 >5,700 >5,700 <1 3 >5,700 Totl Coliform MPN/100 ml 1.1 >23 >23 >23 >23 >2,400 4 >23 Fecl Coliform MPN/100 ml 1.1 >23 >23 >23 >23 >2,400 4 >23 E. Coli MPN/100 ml 2 >23 >23 >23 >23 >2,400 4 > The UF trin ws smpled on Februry 16 nd 23, 2011; the MBR trin ws smpled on four dtes: Mrch 2 nd 9, 2011, nd My 15 nd 22, ND = not detected, NS = not smpled 3 This smple hd n unusully low HPC vlue; the lbortory likely switched this smple with the LP UV smple, which ws expected to be < 10 cfu/ml but ws > 5,700 cfu/ml on this dte. 4 Method SM 9223B ws used to nlyze totl coliform nd fecl coliform on My 15, 2012, nd E. coli on My 15 nd 22, This method hd different mesurement rnge (on My 15, 2012) from SM 9221B, which ws used for ll other totl coliform, fecl coliform, nd E. coli smples.

124 Tble 7-3. Title 22+ Anlytes Detected in Secondry Effluent: Trce Orgnic Constituents 104 Reporting Phse 1 1 Phse 1 1 Phse 3 1 Ctegory Anlyte Units Limit 2/16/11 2/23/11 3/2/11 3/9/11 5/15/12 5/22/12 Hormones 17 -Estrdiol ng/l ND 3 ND 3 ND Estrone ng/l Industril Bisphenol A ng/l EDCs 4-Nonylphenol (Tech Mix) ng/l ,100 1,000 1,200 2, Nonylphenol Monoethoxylte ng/l 125 2,360 2,630 2,670 3,280 4,820 5,120 Nonylphenol Diethoxylte ng/l 125 8,000 9,550 8,100 9,700 6,980 7,000 4-tert Octylphenol ng/l Octylphenol Monoethoxylte ng/l 125 1,400 1,040 1,090 1,270 1,160 1,000 Octylphenol Diethoxylte ng/l 125 4,850 4,150 3,530 3,860 1,560 1,540 PPCPs Azithromycin ng/l 10 1, Acetminophen ng/l ND 3 ND Crbmzepine ng/l ND 3 ND 3 ND 3 ND DEET ng/l Dilntin ng/l ,520 1,330 Gemfibrozil ng/l 20 1,170 1,180 1,210 1, Ibuprofen ng/l ND 3 ND 3 ND 3 ND Meprobmte ng/l Sulfmethoxzole ng/l ,000 1, Triclosn ng/l Other Cffeine ng/l Wstewter Iopromide ng/l 30 1, ,280 1,140 Indictors Sucrlose ng/l 40 20,800 19,900 21,000 19,300 30,800 33,600 TCEP ng/l The UF trin ws smpled on Februry 16 nd 23, 2011; the MBR trin ws smpled on four dtes: Mrch 2 nd 9, 2011, nd My 15 nd 22, Reporting limit ws 10 ng/l for smples tken in 2011, 20 ng/l for smples tken in ND = not detected.

125 Tble 7-4. Other Title 22+ Anlytes Detected in Secondry Effluent 105 Reporting Phse 1 1 Phse 1 1 Phse 3 1 Ctegory Anlyte Units Limit 2/16/11 2/23/11 3/2/11 3/9/11 5/15/12 5/22/12 Voltile Dibromomethne g/l Orgnic Bromochloromethne g/l Compounds Dichloromethne g/l Chloroform g/l Totl THM g/l Methyl Tert-butyl Ether (MTBE) g/l SVOCs Di(2-Ethylhexyl) Phthlte g/l 0.6 ND 2 ND ND 2 ND 2 Crbmte 3-Hydroxycrbofurn g/l Pesticides Aldicrb Sulfone g/l SWRCB Surrogtes Dissolved Orgnic Crbon mg/l Other t-butyl Alcohol g/l Chemicls Crbon Disulfide g/l Chlorte g/l ND 2 Formldehyde g/l Phenol g/l ND 2 1 The UF trin ws smpled on Februry 16 nd 23, 2011; the MBR trin ws smpled on four dtes: Mrch 2 nd 9, 2011, nd My 15 nd 22, ND = not detected.

126 7.2 TREATMENT TRAIN #1: UF-RO-AOP UF Results Of the 74 nlytes tht were consistently detected in the secondry effluent (excluding 1,4- dioxne nd the nitrosmines, which were discussed in Chpter 6), UF hd cler effect on 21 nlytes. These nlytes re listed in Tble 7-5, long with the totl chlorine residul, which incresed cross the UF to consistently detected levels. The vlues listed in Tble 7-5 re the verge of the two vlues for the smple sets tken on Februry 16 nd 23, Tble 7-5. Results for the UF Ctegory Anlyte Units Secondry Effluent UF filtrte % Chnge Generl Cynide mg/l Prmeters Orgnic Nitrogen mg N/L Totl Phosphorus mg P/L Turbidity NTU* UV Trnsmittnce (254 nm) % Trce Metls Iron mg/l Microbes Cryptosporidium Oocysts/10L 2 <1 >50 Girdi Cysts/10L 1, Heterotrophic Plte Count cfu/ml >5, > 98 Totl Coliform MPN/100 ml >23 <1.1 > 95 Fecl Coliform MPN/100 ml >23 <1.1 > 95 E. Coli MPN/100 ml >23 <2 > 91 Hormones Estrone ng/l Industril EDCs Bisphenol A ng/l Nonylphenol (Tech Mix) ng/l 1, Nonylphenol Monoethoxylte ng/l 2,490 1, tert Octylphenol ng/l PPCPs Sulfmethoxzole ng/l Triclosn ng/l SWRCB Surrogtes Totl Chlorine Residul mg/l < >8,600 Other Chemicls Chlorte g/l ,438 Formldehyde g/l *NTU = nephelometric turbidity unit 106

127 The UF removed solids from the effluent, which probbly ccounts for the observed increse in UV trnsmittnce nd the removl of the turbidity, phosphorus, orgnic nitrogen, iron, nd microorgnisms. Severl trce orgnic constituents were lso removed by the UF, most likely due to sorption to solids tht were then removed by the UF membrnes (Snyder et l., 2007; Colemn et l., 2009; Cirj et l., 2006). Additionl removl my hve occurred through rection with the chlorine tht ws dded to the UF influent to form chlormines, which helped control biofouling of the membrnes (Tng et l., 2010). Chlorine ddition incresed the totl chlorine residul, nd my hve lso cused the observed increses in cynide nd formldehyde, which re known disinfection byproducts (DBPs) of chlorintion (USEPA, 1999; Kvnugh et l., 2003; N nd Olson, 2006; Krsner et l., 1989), nd chlorte, which is formed in hypochlorite solutions due to the decomposition of hypochlorite (Bolyrd et l., 1992). In summry, 74 nlytes were detected in the UF influent. Four types of microorgnisms were removed to below detection: Cryptosporidium, totl coliform, fecl coliform, nd E. coli. The concentrtions of n dditionl four compounds (luminum, vndium, rdium 228, nd crbon disulfide) lso decresed to below the reporting limit; these compounds were not listed in Tble 7-5, becuse the level in the UF filtrte were generlly very close to the reporting limit, so the chnge cross the UF ws smll. The totl chlorine residul incresed to consistently detected levels. Overll, totl of 67 nlytes were detected in the UF filtrte RO Results RO effectively removed most of the Title 22+ prmeters. Of the 67 nlytes tht were detected in the UF filtrte (excluding 1,4-dioxne nd the nitrosmines, which were discussed in Chpter 6), 19 were consistently detected in the RO effluent. These nlytes re listed in Tble 7-6. The ph decresed cross RO, becuse sulfuric cid ws dded to the RO influent to reduce precipittion nd inorgnic fouling of the membrnes. The UV trnsmittnce incresed cross RO, likely due to the dditionl removl of prticles nd orgnics. Of the other detected nlytes, most were removed by > 90%. The exceptions were boron, which ws removed by 33%; formldehyde, which ws reduced by 83%; chloroform nd totl THMs (which consisted primrily of chloroform), which were reduced by < 50%; nd the dihlomethnes nd totl chlorine residul, which showed very little removl by RO. All of these compounds re smll molecules, which re difficult to remove by RO. In summry, 67 nlytes were detected in the RO influent. Most were effectively removed by RO to below detection. A totl of 19 nlytes were detected in the UF-RO effluent. As shown in Tble 7-6, the trget concentrtions were met for ll prmeters except boron, which is discussed in more detil in Section 5.3.1, nd ph. The RO permete would likely require tretment (e.g., decrbontion nd lime ddition) to rise the ph before use. 107

128 Tble 7-6. Results for the UF-RO UF RO % Trget Ctegory Anlyte Units Filtrte Permete Chnge Conc. Generl Alklinity, Totl mg CCO 3 /L NA* Prmeters Ammoni mg N/L NA* Boron mg/l Bromide g/l 1, NA* Chloride mg/l Fluoride mg/l ph Sodium mg/l NA* Specific Conductnce, 25ºC mho/cm 2, ,600 Totl Dissolved Solids mg/l 1, UV Trnsmittnce (254 nm) % NA* Voltile Dibromomethne g/l NA* Orgnic Bromochloromethne g/l NA* Compounds Dichloromethne g/l Chloroform g/l NA* Totl THM g/l SWRCB Surrogtes Totl Chlorine Residul mg/l NA* Other Chlorte g/l Chemicls Formldehyde g/l *NA = Not pplicble AOP Results The full suite of Title 22+ prmeters ws smpled on Februry 16, 2011; only the polybrominted diphenyl ether compounds nd trce orgnic constituents were mesured on Februry 23, Nineteen nlytes (excluding 1,4-dioxne nd the nitrosmines, which were discussed in Chpter 6) were detected in the UF-RO effluent, nd the concentrtions of n dditionl six compounds rose to detectble levels in the AOP effluent. Tble 7-7 presents the results for these 25 nlytes. For Phse 1, only dt from Februry 16, 2011, were considered, becuse no AOP smples were tken on Februry 23, 2012; consequently, the RO permete concentrtions do not necessrily mtch the vlues in Tble 7-6. Alklinity decresed slightly, possibly due to the rection of bicrbonte ions with hydroxyl rdicls (Wng et l., 2000). UV photolysis of chlormines (Wtts nd Linden, 2007) likely cused the observed decrese in the totl chlorine residul, nd increses in the concentrtions of nitrte nd chloride. Nitrte my lso hve been formed from the rection of mmoni with hydroxyl rdicls (Bonsen et l., 1997; Pollem et l., 1992); this rection hs been observed in photoctlytic TiO 2 systems, which lso utilize hydroxyl rdicls. Bromide concentrtions lso incresed; resons for this increse re uncler. 108

129 Tble 7-7. Title 22+ Results for AOP (UF Trin) Ctegory Anlyte Units RO Permete 1 AOP Effluent % Chnge Generl Alklinity, Totl mg CCO 3 /L Prmeters Ammoni mg N/L Boron mg/l Bromide g/l Chloride mg/l Fluoride mg/l Nitrte mg N/L < > 220 Nitrte + Nitrite, Totl mg N/L < > 60 ph Sodium mg/l Specific Conductnce, 25ºC mho/cm Totl Dissolved Solids (TDS) mg/l UV Trnsmittnce (254 nm) % Trce Chromium, Hexvlent g/l < > 160 Metls Copper g/l < 2 27 > 1,250 Led g/l < > 36 Voltile Dibromomethne g/l 0.67 < 0.5 > 25 Orgnic Bromochloromethne g/l Compounds Dichloromethne g/l Chloroform g/l Totl THM g/l SWRCB Dissolved Orgnic Crbon mg/l < > 30 Surrogtes Totl Chlorine Residul mg/l Other Chlorte g/l 11 < 10 > 9 Chemicls Formldehyde g/l Vlues re from only Februry 16, 2011, when mtching smples from the AOP were tken; these numbers my not mtch the verge RO vlues in Tble 7-6. Among the orgnic compounds, formldehyde concentrtions incresed cross the AOP; this observtion is consistent with published literture on UV disinfection (Awd, 1993; Mlley et l., 1995). Despite the increse, the formldehyde concentrtion in the finl product wter ws well below the trget concentrtion of 100 g/l. In ddition, dibromomethne concentrtions decresed slightly nd dissolved orgnic crbon concentrtions incresed slightly, but these chnges were smll, nd my be within norml smpling/nlyticl vribility. Finlly, the concentrtions of hexvlent chromium, copper, nd led incresed. These increses my indicte tht the RO permete leched metls from the UV rectors or fittings; cre should be tken to ensure tht such leching does not occur in the full-scle system. Despite the increses, the finl concentrtions of ll nlytes except boron remined below the pplicble trget concentrtions. 109

130 7.3 TREATMENT TRAIN #2: MBR-RO-AOP MBR Results Of the 72 nlytes tht were consistently detected in the secondry effluent (excluding 1,4- dioxne nd the nitrosmines, which were discussed in Chpter 6), the MBR hd ffected 40 nlytes. These 40 nlytes re listed in Tbles 7-8 nd 7-9, long with cetminophen nd the two nitrte nlytes, which incresed cross the MBR to detectble levels. The performnce of the MBR ws generlly quite similr in Phses 1 nd 3. The three exceptions were chromium, phenol, nd cetminophen. Chromium concentrtions decresed by 0.3 g/l in Phse 1, but incresed by 9.8 g/l in Phse 3. Phenol decresed by > 0.17 g/l in Phse 1, but incresed by 0.19 g/l in Phse 3. Acetminophen incresed by 22 ng/l in Phse 1, but concentrtions did not chnge in Phse 3. The reltively smll mgnitude of the chnges nd the inconsistent behvior suggests tht the MBR hs little effect on ny of these compounds. Like the UF, the MBR removed solids from the effluent, which my ccount for the observed increse in UV trnsmittnce nd the removl of the turbidity, phosphorus, some orgnic nitrogen, iron, luminum, nd microorgnisms. In ddition, biologicl nitrifiction within the MBR decresed concentrtions of mmoni, orgnic nitrogen, lklinity, nd orgnic mtter (TOC nd DOC) nd incresed concentrtions of nitrte. Literture indictes tht biologicl ctivity my lso be responsible for decreses in the levels of color, formldehyde, t-butyl lcohol, trihlomethnes, nd dichloromethne (Willims nd Pirbzri, 2007; Jerusutthirk et l., 2011; Morrison et l., 2002; Whmn et l., 2006; Whmn et l., 2005; IPCS, 1996). In ddition, the decrese in mngnese levels my be ttributble to uptke nd oxidtion by microbes in the MBR (Nelson, et l., 1998). Although reduced mngnese is soluble, the oxidized form is precipitte tht cn be filtered out by the membrnes. Abiotic oxidtion by oxygen or chlorine is reltively slow t neutrl ph (Crittenden et l., 2005), but oxidtion by bcteri nd other microorgnisms cn be fster (Nelson et l., 1988). For the trce orgnic constituents, concentrtions of sulfmethoxzole incresed, while the concentrtions decresed for the other 11 compounds (excluding cetminophen, which ws discussed bove). The chnges in the sulfmethoxzole concentrtions my simply represent the nturl vribility in the smples or nlyses. Both the UF nd MBR provided removl of severl trce orgnic constituents, but the UF generlly provided more removl of the following six compounds: estrone, bisphenol A, nonylphenol, nonylphenol monoethoxylte, octylphenol, nd triclosn. The extr removl of these compounds by the MBR my be due to biologicl ctivity, sorption to solids tht were then removed from the effluent by the membrnes, or combintion of the two mechnisms (Schröder et l., 2006; Chen et l., 2008; Colemn et l., 2009; Snyder et l., 2007). Six compounds were removed by the MBR but not the UF: nonylphenol diethoxylte, octylphenol diethoxylte, octylphenol monoethoxylte, gemfibrozil, DEET, nd cffeine. These results re consistent with biologicl ctivity, which hs been reported in the literture for these compounds (Snyder et l., 2007; Schröder et l., 2006; Chen et l., 2008; Colemn et l., 2009). 110

131 Tble 7-8. Title 22+ Results for the MBR: Generl Prmeters, Trce Metls, Rdiologicl Anlytes, nd Microbes 111 Ctegory Anlyte Units Secondry Effluent Phse 1 Phse 3 MBR Permete % Chnge Secondry Effluent MBR Permete % Chnge Generl Alklinity, Totl mg CCO 3 /L Prmeters Ammoni mg N/L Apprent Color ACU Cynide mg/l Nitrte mg N/L < ,900 < ,900 Nitrte + Nitrite, Totl mg N/L < ,900 < ,900 Orgnic Nitrogen mg N/L 2.5 <1 > <1 > 68 Totl Orgnic Crbon mg/l Totl Phosphorus mg P/L Turbidity NTU UV Trnsmittnce (254 nm) % Trce Metls Aluminum g/l 26 <20 > <20 > 20 Iron mg/l Mngnese g/l Rdiologicl Urnium pci/l Microbes Cryptosporidium Oocysts/10L 1.5 <1 > 33 NS 1 NS 1 NS 1 Girdi Cysts/10L 1,720 <1 100 NS 1 NS 1 NS 1 Heterotrophic Plte Count cfu/ml >5,700 3,350 > Totl Coliform MPN/100 ml > > 71 > > 78 Fecl Coliform MPN/100 ml > > 95 >23 <1 > 96 E. Coli MPN/100 ml >23 <2 > 91 >23 <1 > 96 1 ACU = pprent color unit, NS = not smpled, NTU = nephelometric turbidity unit. 2 Inconsistently detected. 3 Vlues ppered to be unrelible, nd re not included in this tble. Bsed on smples tken on other dtes, HPC vlues (in cfu/ml) for the secondry, MBR, nd UV effluents were expected to be >5,700, pproximtely 3,000, nd < 30, respectively. However, on My 15, 2012, the secondry effluent HPC ws <1 cfu/ml nd the LP UV ws >5700 cfu/ml. On My 22, 2012 the MBR permete HPC ws <1 nd LP UV HPC ws 2,500 cfu/ml. It is likely tht these two sets of smples were switched.

132 Tble 7-9. Title 22+ Results for the MBR: Other Anlytes 112 Ctegory Anlyte Units Secondry Effluent Phse 1 Phse 3 MBR Permete % Chnge Secondry Effluent MBR Permete % Chnge Hormones Estrone ng/l 21 <10 > <1.2 > 97 Industril EDCs Bisphenol A ng/l Nonylphenol (tech mix) ng/l 1, , Nonylphenol Monoethoxylte ng/l 2, , Nonylphenol Diethoxylte ng/l 8, , tert Octylphenol ng/l Octylphenol Monoethoxylte ng/l 1,180 <125 >89 1,080 <63 > 94 Octylphenol Diethoxylte ng/l 3, ,550 <63 > 96 PPCPs Acetminophen ng/l <10 22 > DEET ng/l Gemfibrozil ng/l 1, , Sulfmethoxzole ng/l 1,120 1, , Triclosn ng/l Other Wstewter Indictors Cffeine ng/l Voltile Dichloromethne g/l 3.9 * * 3.0 < 0.5 > 83 Orgnic Chloroform g/l Compounds Totl THM g/l SWRCB Surrogtes Dissolved Orgnic Crbon mg/l Other Chemicls t-butyl Alcohol g/l 8.8 <2.0 > <2 > 73 Chlorte g/l 27 <10 > <10 > 53 Formldehyde g/l Phenol g/l 0.37 <0.20 > *Inconsistently detected.

133 The cuse of the decrese in chlorte concentrtion is unknown. Chlorte is not voltile, nd does not sorb strongly to solids (Gonce nd Voudris, 1994). It cn be biodegrded under reducing conditions (vn Ginkel et l., 1995), but should not be reduced under the erobic conditions within the MBR. In summry, 72 nlytes were detected in the MBR influent. Three ctegories of microorgnisms (Cryptosporidium, Girdi, nd E. Coli) nd six other nlytes in Tbles 7-8 nd 7-9 (orgnic nitrogen, luminum, estrone, octylphenol monoethoxylte, t-butyl lcohol, nd chlorte) were removed to below detection. The concentrtions of four dditionl nlytes (crbon disulfide, bromochloromethne, dibromomethne, nd MTBE) lso decresed to below the reporting limit, nd totl chlorine residuls were incresed to the reporting limit of 0.05 mg/l; these compounds were not listed in Tbles 7-8 nd 7-9 becuse the levels were generlly very close to the reporting limit, so the chnge cross the MBR ws smll. Concentrtions of three nlytes (nitrte, totl nitrte nd nitrite, nd cetminophen) incresed from below detection to detectble levels. Overll, totl of 63 nlytes were detected in the MBR permete RO Results RO effectively removed most of the Title 22+ prmeters. Of the 63 nlytes tht were detected in the MBR permete (excluding 1,4-dioxne nd the nitrosmines, which were discussed in Chpter 6), 18 were consistently detected in the RO effluent. In ddition, the concentrtions of two nlytes (bromodichloromethne nd chlorodibromomethne) incresed to consistently detected levels. These 20 nlytes re listed in Tble The performnce of the MBR ws generlly similr in Phses 1 nd 3. The only exception ws chloroform, which decresed by 0.2 g/l in Phse 1 but incresed by 0.35 g/l in Phse 3; these chnges re smll nd suggest tht the RO hd little effect on chloroform. The totl chlorine residuls incresed nd the ph decresed cross RO, becuse chlormines nd sulfuric cid were dded to the RO influent to reduce fouling of the membrnes. The ddition of chlormines (dded s mmoni, followed by chlorine) likely lso cused the observed increses in the concentrtions of the THMs (bromodichloromethne nd chlorodibromomethne) nd mmoni. The UV trnsmittnce incresed cross RO, likely due to the removl of prticles nd orgnics. Of the other detected nlytes, most were removed by > 90%. The exceptions were turbidity, which ws removed by 37-55%; boron, which ws removed by 32-54%; formldehyde, which ws reduced by 30-39%; nd chloroform, which showed little removl by RO. It is uncler why turbidity remined in the RO permete, lthough the concentrtions were close to the reporting limit of 0.05 mg/l. The other detected compounds re smll molecules tht re difficult to remove by RO. In summry, 63 nlytes were detected in the RO influent. Most were effectively removed by RO to below detection. A totl of 20 nlytes were detected in the MBR-RO effluent. As shown in Tble 7-10, the trget concentrtions were met for ll prmeters except boron, which is discussed in more detil in Section 5.3.1, nd ph. The RO permete would likely require tretment (e.g., decrbontion nd lime ddition) to rise the ph before use. 113

134 Tble Title 22+ Results for the MBR-RO 114 Ctegory Anlyte Units MBR Permete Phse 1 Phse 3 RO Permete % Chnge MBR Permete RO Permete % Chnge Generl Alklinity, Totl mg CCO 3 /L NA 1 Prmeters Ammoni mg N/L NA 1 Boron mg/l Trget Conc Bromide g/l 1, , NA 1 Chloride mg/l Fluoride mg/l Nitrte mg N/L Nitrte + Nitrite, Totl mg N/L ph Sodium mg/l NA 1 Specific Conductnce, 25ºC mho/cm 2, , ,600 Totl Dissolved Solids mg/l 1, , Turbidity NTU UV Trnsmittnce (254 nm) % NA 1 Voltile Chlorodibromomethne g/l < > 190 < >92 NA 1 Orgnic Bromodichloromethne g/l < > 190 < >240 NA 1 Compounds Chloroform g/l NA 1 Totl THM g/l SWRCB Surrogtes Totl Chlorine Residul mg/l , ,200 NA 1 Other Chemicls Formldehyde g/l NA = not pplicble, NTU = nephelometric turbidity unit. 2 Bromoform ws detected in one of the two RO permete smples t concentrtion of 2.4 g/l, but not detected in the other smple. As result, the totl THM vlue (which includes bromoform) is higher thn the sum of the THM species shown in Tble 7-10.

135 7.3.3 AOP Results The full suite of Title 22+ prmeters ws smpled on Mrch 2, 2011, My 15, 2012, nd My 22, 2012; only the polybrominted diphenyl ether compounds nd trce orgnic constituents were mesured on Mrch 9, Twenty nlytes (excluding 1,4-dioxne nd the nitrosmines, which were discussed in Chpter 6) were consistently detected in the MBR-RO effluent, nd the concentrtions of n dditionl four compounds (hexvlent chromium, copper, led, nd rdium 228) rose to detectble levels in the AOP effluent. For Phse 1, only dt from Mrch 2, 2011, were considered, becuse no AOP smples were tken on Mrch 9, 2012; consequently, the RO permete concentrtions do not necessrily mtch the vlues in Tble Becuse bromoform ws detected on Mrch 2, 2011, it is included in the nlysis. Tble 7-11 presents the results for these 27 nlytes. AOP hd little observble effect on most of the nlytes, in prt becuse the RO permete concentrtions were very low. As result, even reltively lrge percent chnges in concentrtions corresponded to smll bsolute chnges. For exmple, the led concentrtion incresed by t lest 32% cross the AOP in Phse 1, but the bsolute chnge ws only 0.2 g/l; it is difficult to determine whether this chnge ws rel or simply vribility in the smpling or mesurement. Similrly, the increse in rdium 228 ws only 0.03 pci/l, occurred only in Phse 1, nd my simply be smpling rtifct. Concentrtions of hexvlent chromium nd copper incresed cross the AOP. The increse in copper levels ws greter in Phse 1 with the Trojn UV rector thn in Phse 3 with the Clgon rector. The increses in the concentrtions of hexvlent chromium were similr for ll three sets of smples. These increses my indicte tht RO permete leched metls from the UV rectors or fittings. The finl concentrtions of these metls in the AOP effluent remined well below the trget concentrtions, but cre should be tken to minimize leching in the full-scle system. As with the UF-RO effluent, lklinity decresed slightly, possibly due to the rection of bicrbonte ions with hydroxyl rdicls (Wng et l., 2000). UV photolysis of chlormines (Wtts nd Linden, 2007) likely cused the observed decrese in the totl chlorine residul, nd increses in the concentrtions of nitrte, chloride, nd TDS. Nitrte my lso hve been formed from the rection of mmoni with hydroxyl rdicls (Bonsen et l., 1997; Pollem et l., 1992); this rection hs been observed in photoctlytic TiO 2 systems, which lso utilize hydroxyl rdicls. Among the orgnic compounds, totl trihlomethne concentrtions decresed, primrily due to decreses in the concentrtions of dibromochloromethne nd bromoform; this result is consistent with results published by Jo et l. (2011), who observed UV photolysis of these two compounds, but not chloroform. Formldehyde concentrtions incresed cross the AOP, which is consistent with literture reports of formldehyde formtion during UV tretment (Awd, 1993; Mlley et l., 1995). The formldehyde concentrtions fter AOP were lrgest in Phse 3 with the Clgon rector nd the LP lmp (63 g/l), followed by the Clgon rector with the MP lmp (41 g/l), then the Trojn rector with the LP lmp (23 g/l); these concentrtions were below the trget of 100 g/l. Overll, the wter qulity resulting from AOP tretment ws similr for the Trojn nd Clgon rectors, nd in the Clgon rector for the LP nd MP lmps, with the possible exceptions of copper nd formldehyde, s discussed bove. Although the concentrtions of some prmeters incresed cross the AOP, the trget concentrtions (where pplicble) were met in ll cses except boron, which ws unchnged cross the AOP. 115

136 Tble Title 22+ Results for AOP (MBR Trin) 116 Ctegory Anlyte Units RO Permete 1 Phse 1 Phse 3 AOP Effluent % Chnge RO Permete LP AOP Effluent % Chnge MP AOP Effluent % Chnge Generl Alklinity, Totl mg CCO 3 /L Prmeters Ammoni mg N/L Boron mg/l Bromide g/l Chloride mg/l Fluoride mg/l Nitrte mg N/L Nitrte + Nitrite, Totl mg N/L Odor TON ph Sodium mg/l Specific Conductnce, 25ºC mho/cm Totl Dissolved Solids mg/l Turbidity NTU UV Trnsmittnce (254 nm) % Trce Chromium, Hexvlent g/l < > 80 < > > 475 Metls Copper g/l < 2 21 > 950 < > > 65 Smpling Led g/l < > 32 < 0.5 < < Rdiologicl Rdium 228 pci/l < < 1 < 1 -- < 1 -- Voltile Bromoform g/l 2.4 < 0.5 > 79 < 0.5 < < Orgnic Chlorodibromomethne g/l 1.5 < 0.5 > < 0.5 > Compounds Bromodichloromethne g/l Chloroform g/l Totl THM g/l SWRCB Surrogtes Totl Chlorine Residul mg/l Other Formldehyde g/l Vlues re from only Mrch 2, 2011, when mtching smples from the AOP were tken; these numbers my not mtch the verge RO vlues in Tble Inconsistently detected.

137 7.4 COMPARISON OF THE UF AND MBR TRAINS Comprison of the UF nd MBR Tbles 7-12 nd 7-13 list the 44 nlytes whose concentrtions chnged cross the UF or MBR. Anlytes tht were removed to similr degrees by the UF nd MBR were likely removed by filtrtion of solids by the 0.04 m membrnes in both units. These nlytes include turbidity, phosphorus, iron, luminum, nd most of the microbiologicl orgnisms. The exceptions were heterotrophic plte count (HPC) nd totl coliform, which hd lower concentrtions in the UF filtrte. High levels of HPC in MBR permetes hve been reported previously in the literture (Friedler et l., 2006; Rhmn nd Al-Mlck, 2006; King County, 2004). The MBR ws operted to nitrify mmoni in the secondry effluent. As discussed in Chpter 5, this process reduced concentrtions of mmoni, orgnic nitrogen, lklinity, nd orgnic crbon (TOC nd DOC) nd incresed concentrtions of nitrte. Literture indictes tht biologicl ctivity my hve lso been responsible for the lower levels, reltive to the UF effluent, of color, t-butyl lcohol, trihlomethnes, nd dichloromethne (Willims nd Pirbzri, 2007; Morrison et l., 2002; Whmn et l., 2006; Whmn et l., 2005; IPCS, 1996). In ddition, the lower mngnese levels in the MBR effluent my be ttributble to uptke nd oxidtion by microbes in the MBR. (Nelson, et l., 1998) Although reduced mngnese is soluble, the oxidized form precipittes nd cn be filtered out by the membrnes. Microbil oxidtion of mngnese cn be fster thn biotic oxidtion by oxygen or chlorine, which is reltively slow t neutrl ph. (Nelson et l., 1988; Crittenden et l., 2005) Differences in chlorine ddition my hve lso cused some differences between the UF nd MBR effluents. Chlorine ws dded to the secondry effluent in the UF trin, nd ws dded upstrem of the RO in the MBR trin. For this study, MBR permete smples were tken upstrem of the mmoni ddition point. As result, the totl chlorine residul ws higher in the UF filtrte thn in the MBR permete. The ddition of chlorine my hve lso cused higher concentrtions in the UF filtrte of cynide nd formldehyde, which re known DBPs of chlorintion (USEPA, 1999; Kvnugh et l., 2003; N nd Olson, 2006; Krsner et l., 1989), nd chlorte, which is formed in hypochlorite solutions due to the decomposition of hypochlorite (Bolyrd et l., 1992). Both the UF nd MBR provided removl of some of the trce orgnic constituents, but likely for different resons. It is likely tht this removl is due to sorption to solids tht were removed by the UF membrnes (Snyder et l., 2007; Colemn et l., 2009; Cirj et l., 2006), lthough it is lso possible tht the compounds rected with the chlorine tht ws dded to form chlormines (Tng et l., 2010). The MBR ws more effective thn the UF t removing most of these compounds, probbly due to biologicl ctivity nd/or to sorption of the compounds to the higher solids concentrtion in the MBR (Drewes et l., 2006; Snyder et l., 2007; Schröder et l., 2006; Chen et l., 2008; Colemn et l., 2009). 117

138 Tble Comprison of UF nd MBR for Title 22+ Generl Prmeters, Trce Metls, Rdiologicl Anlytes, nd Microbes 118 Ctegory Anlyte Units UF Filtrte % Chnge Phse 1 Phse 3 MBR Permete % Chnge MBR Permete % Chnge Generl Alklinity, Totl mg CCO 3 /L Prmeters Ammoni mg N/L Apprent Color ACU Cynide mg/l * * Nitrte mg N/L < , ,900 Nitrte + Nitrite, Totl mg N/L < , ,900 Orgnic Nitrogen mg N/L <1 > 60 <1 > 68 Totl Orgnic Crbon mg/l Totl Phosphorus mg P/L Turbidity NTU UV Trnsmittnce (254 nm) % Trce Metls Aluminum g/l < 20 > 7.5 < 20 > 22 <20 > 20 Iron mg/l Mngnese g/l Rdiologicl Urnium pci/l Microbes Cryptosporidium Oocysts/10L < 1 > 50 < 1 > 33 NS NS Girdi Cysts/10L < NS NS Heterotrophic Plte Count cfu/ml 66 > 98 3,350 > 41 ** ** Totl Coliform MPN/100 ml < 1.1 > > > 78 Fecl Coliform MPN/100 ml < 1.1 > > 95 <1.1 > 96 E. Coli MPN/100 ml < 2 > 91 < 2 > 91 <1.1 > 96 *Cynide ws inconsistently detected in both the MBR influent nd permete. **Vlues ppered to be unrelible, nd re not included in this tble. Bsed on smples tken on other dtes, HPC vlues (in cfu/ml) for the secondry, MBR, nd UV effluents were expected to be >5,700, pproximtely 3,000, nd < 30, respectively. However, on My 15, 2012, the secondry effluent HPC ws < 1 cfu/ml, nd LP UV ws > 5,700 cfu/ml. On My 22, 2012, the MBR permete HPC ws < 1 nd the LP UV HPC ws 2,500 cfu/ml. It is likely tht these two sets of smples were switched.

139 Tble Comprison of UF nd MBR for Other Title 22+ Prmeters 119 Ctegory Anlyte Units UF Filtrte % Chnge Phse 1 Phse 3 MBR Permete % Chnge MBR Permete % Chnge Hormones Estrone ng/l <10 > 51 < Industril EDCs Bisphenol A ng/l Nonylphenol (tech mix) ng/l Nonylphenol monoethoxylte ng/l 1, Nonylphenol diethoxylte ng/l 7, tert Octylphenol ng/l Octylphenol monoethoxylte ng/l 1, < <62.5 > 94 Octylphenol diethoxylte ng/l 4, <62.5 > 96 PPCPs Acetminophen ng/l > DEET ng/l Gemfibrozil ng/l 1, Sulfmethoxzole ng/l , , Triclosn ng/l Other Wstewter Indictors Cffeine ng/l Voltile Dichloromethne g/l <0.5 > 83 Orgnic Chloroform g/l Compounds Totl THM g/l SWRCB Dissolved Orgnic Crbon mg/l Surrogtes Totl Chlorine Residul mg/l 4.2 > 8,600 < < Other Chemicls t-butyl Alcohol g/l <2.0 > 77 <2.0 > 73 Chlorte g/l 615 1,438 <10 > 63 <10 > 53 Formldehyde g/l Phenol g/l <0.20 >

140 7.4.2 Comprison of the RO Permetes Tble 7-14 lists the 26 nlytes remining fter UF-RO or MBR-RO. Mny of the differences tht were observed between the UF nd MBR disppered fter RO. For exmple, trce orgnic constituents (with the exception of the nitrosmines nd 1,4-dioxne, which were discussed in Chpter 6) were not detected in the RO permete from either the UF or MBR trin. Some differences did crry over to the RO permetes, such s differences cused by nitrifiction in the MBR. The nitrte concentrtions were higher in the MBR-RO permete thn in the UF-RO permete, nd lklinity nd mmoni levels were lower. The loction of chlorine ddition lso cused differences in removls between the two RO permetes. Chlorine ws dded to the secondry effluent in the UF trin, nd ws dded upstrem of the RO in the MBR trin. Consequently, in the UF trin, chlorine residuls nd DBP concentrtions incresed cross the UF, nd decresed cross the RO. In the MBR trin, chlorine residuls nd DBP concentrtions incresed cross the RO. As result, the percent removls were different for the UF-RO nd MBR-RO; however, the RO permete concentrtions were similr between the two units, prticulrly within Phse 1 (both the chlorine residuls nd THM concentrtions were slightly lower in Phse 3). Interestingly, the distribution of hlogented methnes differed between the UF-RO nd MBR- RO trins. Three dihlomethnes (dibromomethne, bromochloromethne, nd dichloromethne) were detected in the UF-RO permete, but not in the MBR-RO permete. In ddition, the THMs in the UF-RO permete were entirely composed of chloroform, but were evenly distributed mong chloroform, bromodichloromethne, nd chlorodibromomethne in the MBR-RO permete. These distributions my reflect differences in the levels of precursor orgnics t the two points of chlorine ddition: the UF influent nd MBR permete Comprison of the AOP Effluents Tbles 7-15 nd 7-16 compre the AOP results for the UF-RO nd MBR-RO trins, for the compounds tht were detected in the RO nd/or UV effluent, excluding the nlytes discussed in Chpter 6. Note tht the Phse 1 dt include only the first dy of smpling, becuse no AOP smples were tken on the second dy of smpling; consequently, the RO permete concentrtions do not necessrily mtch the vlues in Tble As discussed in Section 7.3.3, the RO permete concentrtions were low; becuse these low vlues cused potentilly misleding removl vlues, RO permete concentrtions re provided insted in Tbles 7-15 nd Note tht the Phse 1 RO permete vlues re single vlues from the dy tht the AOP smples were lso tken, nd do not mtch the verge vlues given in Tble AOP hd similr effects on most compounds in both effluents, such s the decrese in lklinity. Formldehyde concentrtions incresed for both effluents; the concentrtions fter AOP remined well below the trget level of 100 g/l. 120

141 Tble Comprison of UF-RO nd MBR-RO 121 Ctegory Anlyte Units UF-RO Permete % Chnge Phse 1 Phse 3 MBR-RO Permete % Chnge MBR-RO Permete % Chnge Generl Alklinity, Totl mg CCO 3 /L Prmeters Ammoni mg N/L Boron mg/l Bromide g/l Chloride mg/l Fluoride mg/l Nitrte mg N/L < Nitrte + Nitrite, Totl mg N/L < ph Sodium mg/l Specific Conductnce, 25ºC mho/cm Totl Dissolved Solids mg/l Turbidity NTU < 0.05 > UV Trnsmittnce (254 nm) % Voltile Dibromomethne g/l < < Orgnic Bromochloromethne g/l < <0.5 1 Compounds Dichloromethne g/l < < Chlorodibromomethne g/l < > >92 Bromodichloromethne g/l < > >240 Chloroform g/l Totl THM g/l SWRCB Surrogtes Totl Chlorine Residul mg/l , ,200 Other Chlorte g/l < 10 3 <10 3 Chemicls Formldehyde g/l Concentrtion ws below detection in both the RO influent nd permete. 2 Bromoform ws detected in one of the two RO permete smples t concentrtion of 2.4 g/l, but not detected in the other smple. As result, the totl THM vlue (which includes bromoform) is higher thn the sum of the THM species shown in Tble Inconsistently detected.

142 Tble Comprison of AOP Tretment on the UF nd MBR Trins: Generl Prmeters, Trce Metls, nd Rdiologicl Anlytes 122 Ctegory Anlyte Units Phse 1 Phse 3 UF Trin MBR Trin MBR Trin AOP RO AOP RO LP AOP Effluent Permete 1 Effluent Permete Effluent RO Permete 1 MP AOP Effluent Generl Alklinity, Totl mg CCO 3 /L Physicl Ammoni mg N/L nd Minerl Boron mg/l Smpling Bromide g/l Chloride mg/l Fluoride mg/l Nitrte mg N/L < Nitrte+Nitrite, Totl mg N/L < ph Odor TON 2 < 1 < Sodium mg/l Specific Conductnce, 25ºC mho/cm Totl Dissolved Solids (TDS) mg/l Turbidity NTU 2 < 0.05 < UV Trnsmittnce (254 nm) % Trce Chromium, Hexvlent g/l < < < Metls Copper g/l < 2 27 < 2 21 < Smpling Led g/l < < < 0.5 < 0.5 < 0.5 Rdiologicl Rdium 228 pci/l < 0.89 < 0.84 < < 1 < 1 < 1 1 Phse 1 vlues re from only from the first dy of smpling (when corresponding AOP smples were tken) nd my not mtch the RO vlues in Tble TON = threshold odor number, NTU = nephelometric turbidity unit. 3 Not consistently detected.

143 Tble Comprison of AOP Tretment on the UF nd MBR Trins: Other Prmeters 123 Ctegory Anlyte Units RO Permete 1 Phse 1 Phse 3 UF Trin MBR Trin MBR Trin AOP RO AOP RO LP AOP Effluent Permete 1 Effluent Permete Effluent MP AOP Effluent Voltile Dibromomethne g/l 0.67 < 0.5 < 0.5 < 0.5 <0.5 <0.5 <0.5 Orgnic Bromochloromethne g/l < 0.5 < Compounds Dichloromethne g/l < 0.5 < 0.5 <0.5 <0.5 <0.5 Bromoform g/l < 0.5 < < 0.5 < 0.5 < 0.5 <0.5 Chlorodibromomethne g/l < 0.5 < < < Bromodichloromethne g/l < 0.5 < Chloroform g/l Totl THM g/l SWRCB DOC mg/l < < 0.50 < Surrogtes Totl Chlorine Residul mg/l Other Chlorte g/l 11 < 10 < 10 < 10 <10 2 <10 Chemicls Formldehyde g/l Phse 1 vlues re from only from the first dy of smpling (when corresponding AOP smples were tken) nd my not mtch the RO vlues in Tble Not consistently detected.

144 One difference between the two effluents ws the lrger decrese in totl THM concentrtions in the MBR-RO effluents. In the UF-RO effluent, the totl THMs were comprised completely of chloroform, which is not susceptible to UV photolysis; in the MBR-RO effluent, much of the THMs consisted of bromoform nd chlorodibromomethne, which cn be photolyzed by UV (Jo, et l., 2011). Consequently, the totl THM concentrtion in the AOP effluent ws slightly lower in the MBR trin thn the UF trin; however, concentrtions in both effluents were well below the trget concentrtion of 80 g/l. Differences were lso observed for copper nd led. The increses in Phse 1 were similr for the MBR nd UF trin; both sets of smples were tken from the Trojn UV rector. The levels of these two metls were lower in Phse 3 with the Clgon rector, possibly due to differences in the rectors or chnges in the wter qulity between Phse 1 nd Phse 3. Ultimtely, the finl concentrtions of these metls in the AOP effluent remined well below the trgets. 7.5 SUMMARY For the three sets of Title 22+ smpling events, 291 prmeters were mesured (excluding 1,4- dioxne nd the nitrosmines, which were discussed in Chpter 6). Of these prmeters, only 78 were consistently detected in t lest one set of smples. The UF nd MBR were both effective t removing nlytes tht were ssocited with prticulte mtter, such s turbidity, phosphorus, iron, luminum, nd microbiologicl orgnisms. Biologicl nitrifiction in the MBR cused lower concentrtions of mmoni, orgnic nitrogen, lklinity, nd orgnic crbon (TOC nd DOC), nd higher concentrtions of nitrte. Biologicl ctivity my lso be responsible for the lower levels, reltive to the UF effluent, of mngnese, color, formldehyde, t-butyl lcohol, trihlomethnes, nd dichloromethne. Concentrtions of some trce orgnic constituents (the lkylphenols nd lkylphenol ethoxyltes, bisphenol A, cffeine, DEET, gemfibrozil, nd triclosn) were lso lower in the MBR permete thn in the UF filtrte, possibly due to biologicl ctivity nd/or sorption to solids in the MBR mixed liquor. The RO units were effective t removing most of the compounds, such s the trce orgnic constituents. Some differences, such s the nitrogen specition, remined even fter RO tretment. In ddition, the distribution of the hlogented methne DBPs differed between the two trins, which my reflect the orgnic content of the two effluents t the point of chlorintion: secondry effluent for the UF trin, nd MBR permete for the MBR trin. The AOP processes behved similrly on both trins. Alklinity decresed slightly, nd concentrtions of hexvlent chromium, copper, nd led incresed, likely due to contmintion from fittings. Formldehyde concentrtions incresed for both effluents but remined well below the trget concentrtion of 100 g/l. The totl THM concentrtions were similr in the RO permetes from the two trins, but were slightly lower in the AOP effluent from the MBR trin thn from the UF trin, due to the fct tht the THM species in the MBR-RO effluent were more susceptible to UV photolysis thn the THM species present in the UF-RO effluent; however, concentrtions in both effluents were well below the trget concentrtion of 80 g/l. Overll, the Title 22+ smpling tested brod rnge of nlytes. The processes on both trins effectively treted the 291 prmeters discussed in this chpter, nd with the exception of boron (discussed in more detil in Section 5.3.1) nd ph (Section 5.4.2), the AOP effluent met ll wter qulity trgets. 124

145 8. SUMMARY The project results re reviewed in this chpter. Section 8.1 provides comprison of UF nd MBR trins. Wter qulity results nd the bility of the pilot-scle system to meet the trget concentrtions re presented in Section 8.2. Section 8.3 provides brief summry of the conclusions. 8.1 COMPARISON OF THE UF AND MBR TRAINS Both the UF nd MBR trins successfully treted secondry effluent from the JWPCP for most constituents of interest, nd both were operted successfully t flux of pproximtely 20 gfd. A summry of the differences between the two trins is presented in Tble 8-1, nd Sections nd provide more detils on differences in opertions nd wter qulity, respectively. Tble 8-1. Comprison of the UF nd MBR Trins Opertion UF-RO-AOP Opertions of UF ws more ffected by the secondry effluent wter qulity; poor secondry effluent wter qulity incresed fouling nd clening requirements MBR-RO-AOP Opertion of MBR ws less ffected by secondry effluent wter qulity; tertiry MBR could be operted t flux similr to the UF flux Design Required smller footprint Required ertion tnk(s) s well s membrne tnk(s) Chemicl Use Energy Use Effluent Wter Qulity Sulfuric cid dose to lower the ph of UF filtrte ws higher Energy to operte the UF system ws lower Medin totl nitrogen concentrtion ws ~2 mg NH 3 -N/L TOC concentrtion ws occsionlly higher thn the trget of 0.5 mg/l Sulfuric cid dose to lower the ph of MBR permete ws much lower becuse the MBR consumed 75% of the secondry effluent lklinity during nitrifiction MBR system required ir scouring of the membrnes, therefore using more energy; ir used for membrne scouring ws sufficient to fully nitrify the secondry effluent in this study Medin totl nitrogen concentrtion ws ~3 mg NO 3 -N/L TOC concentrtion ws consistently below the trget of 0.5 mg/l AOP removl of nitrosmines nd 1,4-dioxne ws slightly better becuse of lower lklinity nd/or higher UVT in the RO permete. 125

146 8.1.1 Opertions The UF hd the dvntge of simplicity over the MBR: it hd smller footprint, nd becuse it lcked biologicl tretment, it required fewer components, nd less process ir nd energy. The UF lso recovered from process upsets more quickly; dys or weeks were sometimes required to bring the MLSS concentrtion in the MBR bck to the desired vlue fter n upset. However, the UF ws prone to fouling nd ws more sensitive thn the MBR to chnges in the JWPCP secondry effluent wter qulity due to events such s rin storms. The greter resistnce to fouling by the MBR membrnes my be due to biologicl ctivity, which could ttenute nd degrde some orgnic foulnts in the secondry effluent, or could be due to the MBR opertion nd clening cycles, which re designed to mintin performnce in the concentrted environment of mixed liquor. As prcticl impliction of this difference, the MBR my require less clening mintennce thn the UF, prticulrly towrd the end of the membrne life. For the two RO units, the biggest difference in opertions ws the sulfuric cid dose required to rech the trget ph vlue. Doses rnged from 97 to 162 mg/l for the UF tretment trin, nd from 3 to 53 mg/l for the MBR tretment trin. These differences re due to the nitrifiction rection tht occurred in the MBR, which produced cid nd consumed lklinity in the wter, thereby reducing the buffering cpcity nd the scling potentil of the effluent. To meet trgets in the AOP system, the hydrogen peroxide dose in MBR-RO permete ws 1-2 mg/l lower thn in the UF-RO permete. This difference ws likely cused either by lower levels of lklinity, which is scvenger of hydroxyl rdicls, or by the higher UV trnsmittnce in the MBR-RO permete. The cost svings from the reduced doses of both sulfuric cid nd hydrogen peroxide could be significnt dvntge for the MBR-RO-AOP process over the UF- RO-AOP process Wter Qulity Severl wter qulity differences were observed between the effluents of the UF nd MBR trins due to biologicl ctivity in the MBR, which likely cused the following trends in the MBR trin: An increse in nitrte concentrtions cross the MBR due to nitrifiction, nd decreses in the concentrtions of mmoni nd TKN. A decrese in lklinity (due to nitrifiction), which decresed chemicl usge in the downstrem processes, s explined in Section Consumption of orgnic mtter (TOC nd COD). The decrese in TOC levels cross the MBR my hve helped to mintin MBR-RO permete concentrtions below the trget of 0.5 mg/l in Phses 1 nd 2, while the UF-RO permete concentrtions occsionlly exceeded the trget; however, this benefit my be mrginl, s both trins consistently met the trget in Phse 3, fter the membrnes in both RO units were replced. Better removl of five nitrosmine compounds: NDMA, NDPA, NDBA, NPIP, nd NPYR. Reduced levels of some trce orgnic constituents: lkylphenols nd lkylphenol ethoxyltes, bisphenol A, cffeine, DEET, gemfibrozil, nd triclosn. Sorption to solids in the MBR mixed liquor, followed by filtrtion through the MBR membrne, my hve lso plyed role in removing these compounds from secondry effluent. Lower levels of mngnese, color, formldehyde, t-butyl lcohol, trihlomethnes, nd dichloromethne. 126

147 The RO units were effective t removing most compounds but some differences remined even fter RO tretment. For exmple, the dominnt nitrogen species ws mmoni in the UF-RO permete, nd nitrte in the MBR-RO permete. In ddition, the distribution of the hlogented methne DBPs differed between the two trins, which my reflect the orgnic content of the two effluents t the points of chlorintion: secondry effluent for the UF trin, nd MBR permete for the MBR trin. Three dihlomethne species (dibromomethne, bromochloromethne, nd dichloromethne) were detected in the UF-RO permete, but not in the MBR-RO permete. Totl THM levels were similr in the two RO permetes, but were entirely composed of chloroform in the UF-RO permete, nd were distributed mong the four species in the MBR-RO permete. Becuse chloroform is not susceptible to UV photolysis, THM concentrtions did not decrese with AOP tretment of the UF-RO permete. THM concentrtions were lower in the MBR-RO-AOP effluent, becuse UV photolyzes bromoform nd chlorodibromomethne. However, totl THM concentrtions in both effluents were well below the trget concentrtion of 80 g/l. 8.2 MEETING WATER QUALITY TREATMENT GOALS The wter qulity trgets for this project were bsed on requirements for groundwter rechrge in Cliforni (Section 3.5). Tbles 8-2 nd 8-3 list the trget concentrtions nd nd the RO effluent concentrtions for ech of these prmeters. Dt from the routine wter qulity smples (Section 3.2) were used where vilble; otherwise, the Title 22+ dt were used insted. As seen in Tbles 8-2 nd 8-3, the concentrtions of lmost ll prmeters were below the trget levels. The following compounds require dditionl explntion: Boron concentrtions did not meet the trget. Boron is difficult to remove, nd lthough technologies such s ion exchnge could be used, source control should be considered to reduce the concentrtions entering the JWPCP. Medin TOC concentrtions met the trget, but mesured vlues occsionlly exceeded the trget in the UF-RO permete during Phses 1 nd 2. Trget levels were consistently chieved during Phse 3 in the UF-RO permete (fter new membrnes were instlled), nd in the MBR-RO permete during ll phses. Becuse TOC concentrtions in RO permetes re generlly < 0.5 mg/l in most AWT systems, TOC is unlikely to be problem in full-scle system, but should be monitored crefully. Medin 1,4-dioxne concentrtions met the trget, but mesured vlues occsionlly exceeded the trget. In ddition, the CDPH DGRR specified tht AOP be used to chieve 0.5-log removl for groundwter rechrge through subsurfce injection. The AOP is discussed in more detil below. Concentrtions of NDMA, NDEA, nd occsionlly NDPA exceeded trgets. The 2008 CDPH DGRR lso specified tht AOP be used to chieve 1.2-log removl for groundwter rechrge through subsurfce injection. AOP results re discussed below. Becuse sulfuric cid ws dded upstrem of the RO units to help control inorgnic fouling, the ph in the RO permete ws pproximtely 5.5, lower thn the trget of As with most AWT systems, the RO permete would likely need to be treted (e.g., with decrbontion nd lime) to rise the ph before use. The reporting limits (RLs) for 17 -estrdiol nd 3-hydroxycrbofurn were greter thn the trget concentrtion, which ws bsed on the monitoring trigger levels (MTLs) from the SWRCB; these MTLs re guidelines, not regultory limits. The RL for 3-127

148 hydroxycrbofurn ws very close to the MTL, indicting tht the concentrtions were ner the MTL or below it. The RL for 17 -estrdiol decresed when the nlyticl method ws improved in Phse 3; concentrtions were < 0.5 ng/l in both Phse 3 MBR- RO smples, suggesting tht the 17 -estrdiol levels were lso below the trget. Tble 8-2. Trget nd Mesured Medin RO Permete Concentrtions for Generl Physicl nd Minerl Prmeters, Trce Metls, nd Rdiologicl Anlytes Trget Mesured Medin Ctegory Constituent Units Conc. UF-RO MBR-RO Generl Chloride mg/l Physicl Color ACU 15 < 3 < 3 nd Conductivity umho/cm 1, Minerl Fluoride mg/l < 0.10 Prmeters Foming Agents (MBAS) mg/l 1 < 0.05 <0.05 Nitrte mg N/L 10 < Nitrite mg N/L 1 < 0.01 < 0.01 Odor TON 3 < 1 < 1 ph Sulfte mg/l 100 < 0.5 < 0.5 TDS mg/l Totl Nitrte + Nitrite mg N/L 10 < 0.1 ~2.8 Totl Nitrogen mg N/L 10 ~1.9 ~2.8 Totl Orgnic Crbon mg/l 0.5 < 0.5 < 0.5 Turbidity NTU 2 < 0.1 < 0.1 Trce Aluminum g/l 50 < 10 < 10 Metls Antimony g/l 6 < 1 < 1 Arsenic g/l 10 < 1 < 1 Brium g/l 1,000 < 0.5 < 0.5 Boron mg/l Chromium (Totl) g/l 50 < 1 < 1 Copper g/l 1300 < 2 < 2 Iron mg/l 0.3 < 0.02 < 0.02 Led g/l 15 < 0.5 < 0.5 Mngnese g/l 50 < 2 < 2 Nickel g/l 100 < 5 < 5 Selenium g/l 50 < 5 < 5 Rdiologicl Gross Bet pci/l 50 < 3 < 3 Urnium pci/l 20 < 0.7 < TON = threshold odor number, NTU = nephelometric turbidity unit. 128

149 Tble 8-3. Trget nd Mesured Medin RO Permete Concentrtions for Other Prmeters Trget Mesured Medin Ctegory Constituent Units Conc. UF-RO MBR-RO 1,4-Dioxne 1,4-Dioxne 1 g/l nd NDMA 2 ng/l Nitrosmines NDEA ng/l NDPA ng/l < 2 NPYR ng/l 20 < 2 < 2 Hormones 17 -estrdiol ng/l 1 < 2 < 2 nd Bisphenol A ng/l 350,000 < 10 < 10 EDCs Nonylphenol ng/l 500,000 < 25 < 25 Octylphenol ng/l 50,000 < 5 < 5 PPCPs Acetminophen ng/l 350,000 < 10 < 10 nd Azithromycin ng/l 3,900 < 10 < 10 Wstewter Crbmzepine ng/l 1,000 < 10 < 10 Indictors Gemfibrozil ng/l 45,000 < 10 < 10 Ibuprofen ng/l 34,000 < 10 < 10 Meprobmte ng/l 260,000 < 10 < 10 Sulfmethoxzole ng/l 35,000 < 10 < 10 Triclosn ng/l 350 < 10 < 10 DEET ng/l 2,500 < 10 < 10 Cffeine ng/l 350 < 10 < 10 Iopromide ng/l 750,000 < 30 < 30 TCEP ng/l 2,500 < 10 < 10 VOCs 3 Dichloromethne g/l < 0.5 MTBE g/l 5 < 0.5 < 0.5 Totl THMs g/l SVOCs 3 Di (2-Ethylhexyl) Phthlte g/l 4 < 0.6 < 0.6 Pesticides 3-hydroxycrbofurn g/l 0.42 < 0.5 < 0.5 Other Formldehyde g/l Tertiry Butyl Alcohol g/l 12 < 2 < 2 Crbon disulfide g/l 160 < 0.5 < 0.5 Chlorte g/l < ,4-dioxne hd n dditionl tretment requirement of 0.5-log removl in both the 2008 nd 2011 DGRRs. 2 NDMA hd n dditionl tretment requirement of 1.2-log removl in the 2008 DGRR; this requirement ws removed in the 2011 drft, but ws kept s trget for this project. 3 VOCs refer to voltile orgnic compounds, nd SVOCs refer to semi-voltile orgnic compounds. 129

150 AOP experiments were conducted to determine the doses required to meet the trget concentrtions for NDMA, NDEA, nd NDPA, s well s the removl requirements for NDMA nd 1,4-dioxne. It should be noted tht UV EED vlues re rector-specific nd cnnot be pplied to ny other rector. The results re summrized in Tble 8-4. The tested doses were sufficient to remove 1,4-dioxne, NDMA, nd NDPA from the highest observed RO permete concentrtions to the trget levels. However, meeting trgets with the highest observed RO permete concentrtion of NDEA required higher doses thn were tested. Tble 8-4. Approximte Hydrogen Peroxide Doses (mg/l) Required to Meet Tretment Gols in the Trojn UV Rector with the Mximum Observed Concentrtions in the RO Permetes UV EED (kwh/kgl) Compound ,4-dioxne ~2 NDMA x 0 0 NDEA x x x NDPA x 6 4 x: Did not meet tretment gols t tested hydrogen peroxide doses. During the Title 22+ smpling, the UV EED ws 4 kwh/kgl nd the hydrogen peroxide dose ws 4 mg/l. Smples tken from the AOP rectors showed smll increses in the concentrtions of nitrte, chloride, formldehyde, hexvlent chromium, copper, nd led. However, concentrtions of ll of these prmeters remined well below the trget levels. Concentrtions of the other mesured nlytes showed no significnt increse, or decrese in concentrtions. 8.3 CONCLUSIONS In summry, the UF-RO-AOP nd MBR-RO-AOP tretment trins successfully met the trgets for lmost ll prmeters, except the following: TOC occsionlly exceeded the trget concentrtion of 0.5 mg/l in the UF-RO-AOP tretment trin. Boron concentrtions exceeded the trget in both tretment trins. It is difficult to remove, nd lthough technologies such s ion exchnge could be used, source control should be considered priority to reduce the concentrtions entering the JWPCP. The ph vlue ws below the trget rnge; dditionl tretment (e.g., with decrbontion nd lime) would likely be needed to rise the ph before use. NDPA nd NDEA re more reclcitrnt thn NDMA to AOP tretment. At the concentrtions resulting from the UF-RO nd MBR-RO systems, the requirements for the AOP doses re likely to be driven by the NDEA removl requirements. NDEA concentrtions incresed cross both the UF nd MBR. The increse cross the UF my be due to chlormintion of the secondry effluent. However, the MBR permete smples were not chlorminted. More work is needed to better understnd the formtion mechnisms of NDEA. 130

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155 APPENDIX A ACRONYMNS

156 AOP: dvnced oxidtion process AWT: dvnced wter tretment BOD: biochemicl oxygen demnd BW: bckwsh CDPH: Cliforni Deprtment of Public Helth CEB: chemiclly enhnced bckwsh (UF) CIP: clen in plce (UF) COD: chemicl oxygen demnd CRWRF: Crson Regionl Wter Recycling Fcility CTS: centrte thickening system (t JWPCP) DBP: disinfection byproduct DEET: N,N-Diethyl-met-tolumide DGRR: Drft Groundwter Rechrge Regultions (by CDPH) DOC: dissolved orgnic crbon EC: extended clen (UF) EDC: endocrine disrupting compound EED: electricl energy dose (for UV) EPA: Environmentl Protection Agency gl: gllons gfd: gllons per squre foot per dy gpm: gllons per minute GWRS: Groundwter Replenishment System HPC: heterotrophic plte count HRT: hydrulic residence time JWPCP: Joint Wter Pollution Control Plnt kgl: kilogllon (1,000 gllons) kwh: kilowtt-hour LADPW: Los Angeles Deprtment of Public Works LP: low pressure (UV lmp) MBR: membrne biorector MC: mintennce clen MCL: mximum contminnt level MF: microfiltrtion MGD: million gllons per dy MLSS: mixed liquor suspended solids MP: medium pressure (UV lmp) MTBE: methyl tertiry-butyl ether MTL: monitoring trigger level MWD: Metropolitn Wter District of Southern Cliforni A-1

157 NA: not pplicble or not vilble ND: not detected NDBA: N-nitrosodi-n-butylmine NDEA: N-nitrosodiethylmine NDMA: N-nitrosodimethylmine NDPA: N-nitrosodi-n-propylmine NL: notifiction level NMEA: N-nitrosomethylethylmine NPIP: N-nitrosopiperidine NPYR: N-nitrosopyrollidine NS: not smpled NTU: nephelometric turbidity unit OCSD: Ornge County Snittion District OCWD: Ornge County Wter District OD: outer dimeter PBDE: polybrominted diphenyl ether PLC: progrmmble logic controller PMCL: primry mximum contminnt level PP: polypropylene PPCPs: phrmceuticls nd personl cre products PVDF: polyvinylidene fluoride RL: reporting limit RO: reverse osmosis RWC: recycled wter contribution SCOD: soluble COD SM: Stndrd Methods SMCL: secondry mximum contminnt level SRT: solids retention time SVOC: semi-voltile orgnic compound SWRCB: Stte Wter Resources Control Bord TCEP: Tris (2-chloroethyl) phosphte TDS: totl dissolved solids THM: trihlomethne TIWRP: Terminl Islnd Wter Reclmtion Plnt TKN: totl Kjeldhl nitrogen TMP: trnsmembrne pressure TOC: totl orgnic crbon TSS: totl suspended solids UF: ultrfiltrtion UV: ultrviolet UVT: UV trnsmittnce VOC: voltile orgnic compound A-2

158 WBMWD: West Bsin Municipl Wter District WPCF: Wter Pollution Control Fcility WRD: Wter Replenishment District WRF: wter reclmtion fcility WRP: wter reclmtion plnt A-3

159 APPENDIX B LITERATURE REVIEW

160 Cse Studies of Indirect Potble Reuse in the United Sttes nd Austrli Prepred by Christopher J. Gbelich, Environmentl Specilist August 2011 B-1

161 This pge intentionlly left blnk B-2

162 TABLE OF CONTENTS SUMMARY... 1 SECTION 1. INTRODUCTION... 3 SECTION 2. REGULATORY OVERVIEW FOR CALIFORNIA... 3 SECTION 3. PERMIT REQUIREMENTS... 6 SECTION 4. CASE STUDIES Groundwter Replenishment System Source Wter Pretretment Reverse Osmosis UV Oxidtion Post Tretment Finl Wter Qulity Specil Studies West Cost Bsin Brrier Project Source Wter Pretretment Reverse Osmosis UV Oxidtion Post Tretment Finl Product Wter Qulity Specil Studies Almitos Brrier Recycled Wter Project Source Wter Pretretment Reverse Osmosis UV Oxidtion Post Tretment Finl Product Wter Qulity Specil Studies Western Austrli Source Wter Pretretment Reverse Osmosis UV Oxidtion Post Tretment Finl Product Wter Qulity Specil Studies Occoqun Reservoir, Virgini Upper Occoqun Service Authority Firfx County Wter Authority REFERENCES i B-3

163 TABLES Tble 1. Full-Scle Indirect Potble Reuse Projects in Cliforni Tble 2. Drft Cliforni Regultions for Groundwter Rechrge into Potble Aquifers Tble 3. Comprison of Methods to Determine Retention Time to Drinking Wter Wells Tble 4. Generl Process Trins for Three Cliforni Cse Studies nd Western Austrli Utilizing Membrne Tretment Tble 5. Wter Qulity Dt for Five Cse Studies Tble 6. Non-crcinogenic Risk Assessment for OCWD GWRS Product Wter Tble 7. Non-crcinogenic Risk Assessment for Snt An River nd Imported Wters Tble 8. Comprison of Crcinogenic Risk for OCWD GWRS nd Snt An River Wter Tble 9. Summry of Trce-Orgnic Compounds Removl cross WBMWD s Brrier Project 63 Tble 10. Wter Qulity Results for Beenyup Pilot Plnt in Western Austrli Tble 11. Log Removl/Inctivtion Credits Adopted for Beenyup Advnced Wter Tretment Plnt in Western Austrli Tble 12. Surrogtes Used to Guge Opertionl Stbility in Western Austrli Tble 13. Suggested Chemicl Indictors to Guge Tretment Performnce in Western Austrli Tble 14. Chemicl Indictors of Recycled Wter Qulity for Western Austrli Tble 15. UOSA Permit Limits Tble 16. Microbil Removl Assessment for Millrd H. Robbins, Jr. Wter Reclmtion Plnt Tble 17. Lnd use in the Occoqun Wtershed bsed on LANDSAT stellite imgery Tble 18. Comprison of FCWA 2005 Lorton WTP nd 2010 Griffith WTP Influent nd Effluent Wter Qulity Dt FIGURES Figure 1. Schemtic Process Digrm of GWRS Figure 2. Specific flux for GWRS over time Figure 3. Improvement in SDI nd MFI fter Chnge to Sludge Blnket Opertion Figure 4. Chemicl Risk Assessment Approch for Western Austrli Figure 5. Tretment Process Flow Digrm for the Millrd H. Robbins, Jr., Wter Reclmtion Fcility Figure 6. Firfx County Wter Authority Wter Tretment Plnt Process Flow Digrms ii B-4

164 ABBREVIATIONS AND ACRONYMS AOP... dvnced oxidtion process Brrier plnt... West Cost Bsin Brrier Project Bsin Plns... Wter Qulity Control Plns BOD... biologicl oxygen demnd CCR... Cliforni Code of Regultions CDPH... Cliforni Deprtment of Public Helth CFR... Code of Federl Regultions CHSC... Cliforni Helth nd Sfety Code CTR... Cliforni Toxics Rule CWC... Cliforni Wter Code DBP... disinfection byproduct DO... dissolved oxygen EDC... endocrine disrupting compound FCWA... Firfx County Wter Authority gfd... gllons per squre foot per dy gpm... gllons per minute Griffith... Frederick P. Griffith, Jr. Wter Tretment Plnt GWRS... Groundwter Replenishment System IAP... Independent Advisory Pnel LACSD... Los Angeles County Snittion District LBWRP... Long Bech Wter Reclmtion Plnt LSI... Lngelier Sturtion Index MCL... mximum contminnt level MDL... method detection limit MF... microfiltrtion MFI... Modified Fouling Index MGD... million gllons per dy MOA... Memorndum of Agreement NDMA... N-Nitrosodimethylmine NPDES... Ntionl Pollutnt Dischrge Elimintion System OCSD... Ornge County Snittion District OCWD... Ornge County Wter District PCB... polychlorinted biphenyls PPCP... phrmceuticls nd personl cre products ppm... prts per million RO... reverse osmosis RQ... risk quotient RWP... Recycled Wter Policy RWQCB... Regionl Wter Qulity Control Bord SDI... Silt Density Index SIP... Policy for Implementtion of Toxics Stndrds for Inlnd Surfce Wters, Enclosed Bys, nd Esturies of Cliforni SWRCB... Stte Wter Resources Control Bord TDS... totl dissolved solids iii B-5

165 TOC... totl orgnic crbon TON... threshold odor number TSS... totl suspended solids TTHM... totl trihlomethne UF... ultrfiltrtion UOSA... Upper Occoqun Service Authority USEPA... United Sttes Environmentl Protection Agency UV... ultrviolet UVT... UV light trnsmittnce VOC... voltile orgnic compounds WBMWD... West Bsin Municipl Wter District WRD... Wter Replenishment District of Southern Cliforni WRP... Wter Reclmtion Plnt WTP... wter tretment plnt WWTP... wstewter tretment plnt iv B-6

166 SUMMARY This report provides three cse studies of indirect potble reuse in Cliforni, two exmples in Western Austrli, nd one exmple from Virgini. The three Cliforni-bsed cse studies include the Groundwter Replenishment System in Fountin Vlley, the West Cost Brrier Project in El Segundo, nd the Almitos Brrier Recycled Wter Project in Long Bech. Ech of these projects is in full-scle opertion. For Western Austrli, the two cse studies re the fullscle Kwinn Wter Reclmtion Plnt nd pilot plnt t the Beenyup Wstewter Tretment Plnt. The Virgini exmple is the Millrd H. Robbins, Jr. Wter Reclmtion Plnt in Centreville, Virgini, which dischrges to surfce wters feeding the Occoqun Reservoir. The purpose of this report is to provide summry of recent findings regrding the implementtion of indirect potble reuse. Ares covered in this report include () brief regultory overview, (b) source nd product wter qulity, (c) complince with ll Federl nd Stte mximum contminnt levels (MCLs), notifiction levels, nd wter tretment nd disinfection nd disinfection by-products rules, nd (d) removl of non-regulted compounds (e.g., phrmceuticls nd personl cre products [PPCPs] nd endocrine disrupting compounds [EDCs]). In Cliforni, regultory oversight of recycled wter projects is crried out by the Cliforni Deprtment of Public Helth (CDPH), Stte Wter Resources Control Bord (SWRCB), nd the individul Regionl Wter Qulity Control Bords (RWQCBs). Permit conditions re set bsed on federl nd stte primry nd secondry MCLs, stte notifiction levels, s well s the stte Anti-degrdtion Policy nd regionl Bsin Plns. CDPH requires the project to use demonstrted tretment technologies tht provide multiple brriers in the design nd opertion of wter reclmtion fcilities for indirect potble reuse to ugment potble wter supplies. With the exception of the Millrd H. Robbins, Jr. Wter Reclmtion Plnt in Virgini, ech plnt trets either secondry or tertiry treted wstewter with combintion of microfiltrtion (MF), reverse osmosis (RO), or ultrviolet light oxidtion (UV). The Groundwter Replenishment System nd West Cost Brrier Project use UV in combintion with hydrogen peroxide s n dvnced oxidtion process (AOP) to oxidize refrctory compounds, such s 1,4- dioxne nd N-nitrosodimethylmine (NDMA). Ech of the MF-RO-UV plnts serve s indirect potble reuse projects tht ugment groundwter supplies through either direct injection or spreding bsins. The Millrd H. Robbins, Jr. Wter Reclmtion Plnt is designed for nutrient removl to improve the wter qulity of the Occoqun Reservoir. Given the difference in reuse objectives, the Millrd H. Robbins, Jr. Wter Reclmtion Plnt further trets secondry wstewter using lime clrifiction, medi filtrtion, crbon contctors, nd chlorine disinfection. The dechlorinted effluent provides pproximtely 20 percent of the surfce wter flow into the Occoqun Reservoir. 1 B-7

167 Ech of the forementioned plnts met or exceeded their permit requirements. Wter qulity criteri include limits on totl dissolved solids (TDS), totl orgnic crbon (TOC), totl nitrogen, totl phosphorous, trce metls, disinfection byproducts (DBPs), nd pthogens. This report contins brief overviews of helth effects studies, unit process selection, MF nd RO membrne performnce studies, trce orgnic compound removl, post-tretment issues, nd the effects of pplying high purity wter in groundwter quifers. 2 B-8

168 SECTION 1. INTRODUCTION Tble 1 provides summry of opertionl indirect potble reuse projects in Cliforni. Indirect potble reuse of treted municipl wstewter hs been prcticed in southern Cliforni since 1962 [1]. In Cliforni, indirect potble reuse hs been limited to ugmenting groundwter quifers vi either surfce spreding, followed by percoltion, or direct injection into the ground. This report provides three cse studies of indirect potble reuse in Cliforni, two exmples in Western Austrli, nd one exmple from Virgini. The three Cliforni-bsed cse studies include the Groundwter Replenishment System in Fountin Vlley, the West Cost Brrier Project in El Segundo, nd the Almitos Brrier Recycled Wter Project in Long Bech. Ech of these projects is in full-scle opertion. For Western Austrli, the two cse studies re the fullscle Kwinn Wter Reclmtion Plnt nd pilot plnt t the Beenyup Wstewter Tretment Plnt. The Virgini exmple is the Millrd H. Robbins, Jr. Wter Reclmtion Plnt in Centreville, Virgini, which provides wter to the Occoqun Reservoir. The purpose of this report is to provide summry of recent findings regrding the implementtion of indirect potble reuse. Ares covered in this report include () brief regultory overview, (b) source nd product wter qulity, (c) complince with ll Federl nd Stte MCLs, notifiction levels, nd wter tretment nd disinfection nd disinfection byproducts rules, nd (d) removl of non-regulted compounds (e.g., PPCPs nd EDCs). The findings in this report re dynmic in nture nd my chnge s dditionl dt in the wter reuse field re obtined. SECTION 2. REGULATORY OVERVIEW FOR CALIFORNIA The August 5, 2008, drft CDPH Title 22, Wter Recycling Criteri does not provide n officil definition of indirect potble reuse [2]. However, lnguge found in Sente Bill (SB) 918 on wter recycling, s submitted by Sentor Pvley on Februry 1, 2010, provides the following definitions [3]: Indirect potble reuse for groundwter rechrge mens the plnned use of recycled wter for replenishment of groundwter bsin or n quifer tht hs been designted s source of wter supply for public wter system; Surfce wter ugmenttion mens the plnned plcement of recycled wter into surfce wter reservoir used s source of domestic drinking wter supply; nd Direct potble reuse mens the plnned introduction of recycled wter either directly into public wter system or into rw wter supply immeditely upstrem of wter tretment plnt. SB 918 ws chrtered nd signed into lw on September 30, 2010 [3]. The lw requires the CDPH to estblish uniform sttewide recycling criteri for: 3 B-9

169 Indirect potble wter reuse for groundwter rechrge by December 31, 2013; Surfce wter ugmenttion by December 31, 2016, if specified expert pnel convened pursunt to the bill finds tht the criteri would dequtely protect public helth; nd Direct potble reuse by December 31, For direct potble reuse, CDPH shll only investigte the fesibility of such, nd not develop uniform criteri. For the purpose of this report, indirect potble reuse is defined s the ugmenttion of drinking wter source (surfce wter or groundwter) with recycled wter followed by n environmentl buffer tht precedes norml drinking wter tretment [1]. Current lw estblishes the SWRCB nd the Cliforni regionl wter qulity control bords s the principl stte gencies with uthority over mtters relting to wter qulity. Regultory oversight of recycled wter projects is crried out by CDPH, SWRCB, nd the individul RWQCBs. CDPH, by sttutory mndte, hs estblished uniform sttewide reclmtion criteri for the vrious uses of reclimed wter, s set forth in Title 22, Recycling Criteri [2]. These criteri estblish the sttutory uthorities over wter reclmtion nd include specified pproved uses of reclimed wter, numericl limittions nd requirements, tretment method requirements, reporting mechnisms, nd performnce stndrds. Use of recycled wter is lso regulted through the Cliforni Wter Code (CWC) nd the Cliforni Helth nd Sfety Code (CHSC). It should lso be noted tht the Recycling Criteri could be considered primrily focusing on domestic wste, s indicted in CWC 60302, which sttes tht the requirements in this chpter shll only pply to recycled wter from sources tht contin domestic wste, in whole or in prt. Bsed on Memorndum of Agreement (MOA) between CDPH nd the SWRCB, CDPH hs the responsibility to identify when nd under wht conditions rw wter supply is suitble for potble purposes [4]. In Cliforni, CDPH hs primcy in enforcing both Federl (United Sttes Environmentl Protection Agency [USEPA], Title 40, Chpter 1 of the Code of Federl Regultions [CFR]) nd the Stte (Title 22, Division 4, Chpter 15 of the Cliforni Code of Regultions [CCR]) drinking wter stndrds. In ddition to estblishing helth-relted drinking wter stndrds, both USEPA nd sttes hve estblished secondry drinking wter stndrds to ssure potble wter supply cceptble in tste, odor, nd ppernce. For some constituents, in lieu of mximum contminnt level (MCL), surfce wter tretment regultions my require tretment technique to minimize the risk ssocited with rw surfce wter supplies. Title 22 MCLs hve been used s bsis for effluent limittions in wter recycling permits to protect the municipl nd domestic supply beneficil use [4]. The RWQCBs rely on the expertise of CDPH for the estblishment of permit conditions needed to protect public helth. CDPH s requirements re then incorported into the sponsor s RWQCB permit in ccordnce with the Title 22 Recycling Criteri. The SWRCB nd the RWQCBs hve the exclusive uthority to enforce wter reclmtion requirements through permit enforcement. 4 B-10

170 The ltest drft groundwter rechrge regultions for indirect potble reuse proposed in 2008 [5] will be included in the Recycling Criteri if they re formlly finlized nd subsequently dopted. Selected requirements in the current published version of the drft regultions re summrized in Tble 2. Severl requirements specified in the drft regultions would lso pply to direct potble reuse projects (e.g., industril pretretment nd source control progrms, n opertions pln, nd contingency pln), nd product wter qulity requirements would be t lest s restrictive s those currently prescribed for indirect potble reuse nd my be more restrictive for some constituents. The existing drft groundwter rechrge regultions re being modified to set comprehensive, objective criteri tht ddress both surfce spreding nd subsurfce injection projects involving indirect potble reuse of the recovered wter [1]. CDPH requires tht multiple brriers be incorported in the design nd opertion of wter reclmtion fcilities tht produce recycled wter for indirect potble reuse to ugment potble wter supplies. The multiple brrier concept is bsed on the principle of estblishing series of brriers to preclude the pssge of microbil pthogens nd hrmful chemicl constituents into the wter system to the gretest extent prcticl [5]. Such brriers my include the following: Source control progrms designed to prevent the entrnce of constituents of emerging concern into the wstewter collection system tht will inhibit tretment or my preclude use of the wter. A combintion of tretment processes (which my include primry, secondry, nd dvnced tretment processes) where ech process provides specific level of constituent reduction. Constituent monitoring t vrious points of tretment. Design nd opertionl procedures to rpidly detect bnormlities in tretment process performnce so tht corrective ction cn be tken. Environmentl buffers tht cn provide dilution, nturl ttenution of contminnts, nd retention time. An environmentl buffer is considered by CDPH to be one of the necessry multiple brriers for indirect potble reuse projects to provide dditionl tretment nd time to tke corrective ction in the event tht ll wter qulity requirements re not met in the product wter. The environmentl buffer in n indirect potble reuse project serves to isolte the public wter system from n immedite concern, such s might be cused by the dischrge of toxic wste to the sewerge system or equipment or tretment problems t the wstewter tretment fcility. Without this buffer, timely notifiction of problems (e.g., source wter deteriortion, tretment process opertionl filures, nd indequte wter qulity) becomes even more importnt. 5 B-11

171 SECTION 3. PERMIT REQUIREMENTS As prt of the permit ppliction process, the pplicnt must submit n engineering report to CDPH nd RWQCB for review nd pprovl. CDPH must hold three public herings before mking finl determintion on ny public helth spects relted to the project. After the public herings, CDPH will consult with RWQCB regrding permit requirements. RWQCB would then issue Ntionl Pollutnt Dischrge Elimintion System (NPDES) permit fter considering how the project complies with regionl Wter Qulity Control Plns (Bsin Plns), Cliforni Toxics Rule (CTR), nd SWRCB s Recycled Wter Policy (RWP) nd Policy for Implementtion of Toxics Stndrds for Inlnd Surfce Wters, Enclosed Bys, nd Esturies of Cliforni (SIP). The Bsin Plns contin wter qulity objectives tht provide resonble protection of the beneficil use of surfce wters nd groundwters within the region. The RWP provides uniform guidelines such tht individul RWQCBs conform with Cliforni s Anti-degrdtion Policy for wter recycling nd groundwter rechrge projects. The Anti-degrdtion Policy requires the use of best prcticl tretment nd control nd tht SWRCB blnce the preservtion of high qulity wter with the mximum benefit of the people of Cliforni. The SIP implements the requirements set for by the CTR [6]. The engineering report shll be prepred by licensed engineer nd hydrologist nd shll clerly indicte the mens by which the project will meet ll regultory requirements [2]. Bsic elements tht re included in the engineering report include source wter chrcteriztion, proposed tretment process, effluent wter qulity monitoring, subsurfce chrcteriztion, product wter blending pln, downstrem monitoring pln, nd opertions pln. All permitting spects for proposed projects re cse specific nd my chnge bsed on discussions with CDPH nd RWQCB stff. The source wter control pln includes n up-to-dte inventory of contminnts dischrged into the wstewter collection system, such tht new contminnts of concern cn be redily identified. Other spects of the source wter control pln include public outrech progrms to mnge nd minimize the dischrge of contmintes (e.g., methylene chloride or PPCPs), nd monitoring progrms for CDPH-specified contminnts. For the selection of the tretment trin, CDPH provides generl guidelines of the level of tretment required depending on the fte of the finl product wter (Tble 2). In generl, for indirect potble reuse projects using direct injection, the tretment trin involves MF, RO, followed by UV oxidtion of post-secondry treted wstewter. CDPH lso provides guidnce s to the selection of tretment technologies for use in indirect potble rechrge projects [7]. The pre-pproved list ws generted from review of files nd correspondence with CDPH detiling system performnce, robustness, nd bility to comply with the conditions set forth in the Wter Recycling Criteri. All dt were reviewed by CDPH nd RWQCB stff, the sponsoring gency, nd industry representtives. The tretment technology guidnce list is periodiclly updted when new informtion becomes vilble. 6 B-12

172 Tble 3 shows the level of effort needed to chrcterize the subsurfce zone within the groundwter rechrge re. Mndted retention times between the injection nd extrction wells vry from 6 to 24 months, depending on the method used in determining the subsurfce retention time. CDPH prefers tht trcer test using n inert compound be conducted. For those projects hving vlid trcer test, the trvel time within the groundwter quifer before finl product wter reches drinking wter production well needs to be greter thn or equl to 6 months. Monitoring plns for the finl product wter need to include: Regulted contminnts mesure ll federl nd stte regulted drinking wter compounds on qurterly bsis, including: o Inorgnic chemicls o Rdionuclides o Orgnic chemicls o Disinfection by-products o Led nd copper; Totl nitrogen three methods for nitrogen control re proposed. The pplicnt my choose which complince method to use depending on the circumstnces: o 5 mg/l totl nitrogen, smples to be tken t no less thn three dys prt; o 10 mg/l totl nitrogen if dissolved oxygen (DO), biologicl oxygen demnd (BOD), nitrte, nitrite, mmoni re within MCLs nd limits estblished in the engineering report. Smpling frequency to be determined by CDPH; o MCLs for nitrte nd nitrite. This option is only llowed for projects in opertion greter thn 20 yers with no evidence of degrdtion of the receiving wter body. Totl orgnic crbon (TOC) 0.5 mg/l for smples tken once per week. TOC complince is bsed on 20-week running verge; Recycled wter contribution ech month, the reuse project shll clculte the running monthly verge of the blend of finl product wter nd blend wter (e.g., surfce wter). The initil mximum recycled wter contribution shll not exceed 50 percent for subsurfce ppliction projects with or without RO, nd dvnced oxidtion processes (AOP; e.g., ultrviolet (UV) oxidtion with hydrogen peroxide) to chieve greter thn 1.2 log N-Nitrosodimethylmine (NDMA) reduction nd 0.5 log 1,4-dioxne reduction. The mximum percent contribution by recycled wstewter is bsed on the following formul: TOC mx = 0.5 mg/l/(recycled wter contribution) (1) Whereby the TOC mx for the receiving wter is determined in the engineering report. For exmple, using Eqution 1 bove, the reltive recycled wter contribution for the finl blended receiving wter would be clculted thus [8]: 7 B-13

173 TOC mx (mg/l) Recycled Wter Contribution % or % or % or % or % or 0.75 Note tht TOC is clculted on 20-week running verge, while recycled wter contribution is clculted on 60-month running verge. Unregulted contminnts with Notifiction Levels. Unregulted contminnts shll not exceed the CDPH Notifiction Levels, s these chemicls hve been identified in typicl wstewter sources. Exmples of unregulted contminnts with notifiction levels (in prentheses) identified in typicl wstewter sources include: o Boron (1 mg/l), o Chlorte (0.8 mg/l), o NDMA ( mg/l), o N-Nitrosodiethymine (NDEA; mg/l), o N-Nitrosodi-n-propylmine (NDPA; mg/l), o 1,2,3-Trichloropropne ( mg/l), o Formldehyde (0.1 mg/l), o Vndium (0.05 mg/l), nd o 1,4-Dioxne (0.001 mg/l). Unregulted Contminnts without Notifiction Levels. Additionl compounds indicted by CDPH for dditionl monitoring include: o Chromium-6 (hexvlent chromium), o Dizinon, nd o Nitrosmines for which USEPA hs developed nlyticl methods. Two clsses of compounds hve lso received incresed interest in recent yers. These chemicl clsses re PPCPs nd EDCs. CDPH is interested in collecting informtion tht reltes to the presence of these compounds in municipl wstewter nd finl recycled wter effluent. While CDPH does not recommend specific chemicls to monitor, it does dvocte tht representtive constituents for these clsses, or surrogtes for their presence be monitored. Monitoring progrms my be short in durtion (e.g., twice yer for two to three yers). Agin, while CDPH does not recommend monitoring for specific compounds t this time, CDPH does recommend the reuse project investigte the following sub-clsses of compounds [2]: 8 B-14

174 Hormones: o Femle hormones, o Mle hormones, or o Approprite surrogtes; Industril EDCs: o Bisphenol A, o Nonylphenol nd nonylphenol polyethoxyltes, o Octylphenol nd octylphenol polyethoxyltes, nd o Polybrominted diphenyl ethers, or o Approprite surrogtes tht could represent one or more of the industril EDCs; Phrmceuticls: o Acetominophen, o Amoxicillin, o Azithromycin, o Crbmzepine, o Ciprofloxcin, o Dilntin, o Gemfibrozil, o Ibuprofen, o Lipitor, o Mepromte, o Sulfmethoxzole, o Trimethoprim, o Slicylic cid, or o Approprite surrogtes tht could represent one or more phrmceuticls; Personl Cre Products: o Triclosn, o DEET, or o Approprite surrogtes tht could represent one or more personl cre products; Other: o Cffeine, o Iodinted contrst medi, o Fire retrdnts such s TCEP, or o Approprite surrogtes tht could represent one or more these compounds. Note CDPH does not intend for the forementioned compounds to comprise definitive list nd compounds my be dded or deleted depending on the outcome of the source wter monitoring progrm. Diluent Wter Monitoring. CDPH requires monitoring of the diluent wter (e.g., surfce wter, groundwter, or stormwter runoff). The diluent wter must meet ll primry 9 B-15

175 MCLs nd Notifiction Levels, s well s be monitored qurterly for nitrte nd nitrite. Additionl monitoring my be required by CDPH bsed on the source wter monitoring results. Monitoring of Subsurfce Blended Wter. Prior to the drinking wter well, the project shll construct monitoring wells whereby the injected wter hs been retined 1 3 months, or t lest 3 months prior to being pumped for domestic supply well. Two smpling events shll be conducted prior to the project strt up nd qurterly therefter. Wter qulity smples shll include TOC, totl nitrogen, nitrte, nitrite, totl coliform bcteri, nd ny wter qulity constituents specified by CDPH. During the first yer of opertion, nd ll time therefter, the tretment fcility shll operte in fshion providing optiml contminnt removl. Within six months of opertion, the tretment plnt shll updte the opertions pln to include ny chnges in opertionl procedures nd submit the revised opertions pln to CDPH for review. SECTION 4. CASE STUDIES Groundwter Replenishment System The Groundwter Replenishment System (GWRS) is joint wter reuse project conducted by the Ornge County Wter District (OCWD) nd Ornge County Snittion District (OCSD). Locted in Fountin Vlley, Cliforni, the GWRS begn opertions in Jnury The plnt supplements existing groundwter supplies through ppliction of the product wter to rechrge bsins in the Ornge County Groundwter Bsin or injected directly to prevent sewter intrusion. Ner-term plns re to increse the cpcity of the fcility from its current rting of 70 million gllons per dy (MGD) to 100 MGD [9]. While the GWRS consists of three mjor components ([1] the Advnced Wter Purifiction Fcility nd pumping sttions; [2] pipeline connecting the tretment fcilities to existing rechrge bsins; nd [3] n expnded sewter intrusion brrier well system), for the purposes of this report, the term GWRS refers to just the Advnced Wter Purifiction Fcility portion of the project. The GWRS consists of microfiltrtion (MF) pretretment, followed by reverse osmosis (RO) membrne tretment nd UV light exposure with hydrogen peroxide (H 2 O 2 ) for dvnced oxidtion [10] (Figure 1). Figure 1. Schemtic Process Digrm of GWRS. SA = sulfuric cid; TI = threshold inhibitor (i.e., ntisclnt) [10] 10 B-16

176 Per OCWD s permit, the key opertionl requirements for GWRS re [11]: 100 percent RO nd AOP tretment for ll finl product wter; Meet or exceed ll federl nd stte drinking wter requirements; 0.5 mg/l TOC; 5 mg/l totl nitrogen; 10 ng/l (prts per trillion) NDMA; 6 month trvel time within the groundwter quifer before finl product wter reches drinking wter production well; Initil blending of sewter intrusion brrier wter to 75:25 rtio with imported drinking wter; Monitor select PPCPs nd EDCs in the finl product wter nd report vlues to RWQCB on qurterly bsis; nd Estblish n Independent Advisory Pnel (IAP) to review the plnt opertions on periodic bsis. All recommendtions from the IAP must be ddressed, but the decision to implement those recommendtions is t the discretion of OCWD. Source Wter Source wter for the GWRS origintes from the neighboring OCSD Plnt No. 1. OCSD service re covers over 479 squre miles of centrl nd northwest Ornge County nd trets wstewter derived from residentil, commercil, nd industril sources. Industril sources comprise pproximtely 16 percent of the wstewter entering OCSD s Plnt No. 1 [12]. The wter sent to GWRS is secondry effluent from either trickling filtrtion or ctivted sludge tretment. The initil greement between OCWD nd OCSD stipulted tht OCWD receive blend of 80 percent ctivted sludge nd 20 percent trickling filter effluent. Since tht time, the 80/20 blend hs been lifted in n effort to mximize production. The secondry effluent is prtilly nitrified effluent with up to 31 mg/l excess mmoni s nitrogen. Tble 5 presents list of verge nd mximum vlues for compounds nlyzed by OCWD from the OCSD Plnt No. 1 effluent from Februry 2008 through April 2010 [13]. For those dt below the method detection limit (MDL), vlues were reported s less thn the MDL. Blnk dt entries indicte tht no dt were provided for tht compound. GWRS influent wter qulity dt reveled the secondry treted wter contined high levels of mmoni (21 mg/l NH 3 -N verge nd 31 mg/l NH 3 -N mximum), color, turbidity, totl nd fecl coliforms, totl dissolved solids (TDS), totl nitrte nd nitrite, nd vrious trce metls. Bsed on permit requirements, limited trce orgnic compounds were monitored in the GWRS influent. However, 1,4-dioxne (1.7 µg/l verge nd 12.6 µg/l mximum) nd N- nitrosodimethylmine (NDMA) (38 ng/l verge nd 330 ng/l mximum) were mesured t levels tht would require further tretment. For rdiologicls, OCWD monitors only for tritium in the influent wter. Averge nd mximum tritium vlues were 149 (± 221) pci/l nd 11 B-17

177 766 (± 232) pci/l, respectively. It should be noted tht the verge tritium level ws below the counting error for tritium. Pretretment Clrified secondry effluent from OCSD Plnt No. 1 trvels by grvity to the screening fcility nd then to the MF system. The screening fcility hs four rotting 2-mm grvity screens to remove lrger prticles from the secondry effluent hed of the MF process. OCWD reported tht upstrem screening ws vitl to mintining MF performnce nd is required s prt of the MF membrne mnufcturer wrrnty conditions [14]. The full-scle MF system consists of 26 submerged MF (CS, Siemens Wter Technology [formerly US Filter/Memcor], Wrrendle, Penn.) cells, ech with 608 polypropylene modules. The nominl hollow fiber pore size is 0.2 micron, nd the recovery rte is between 88 percent nd 90 percent. The MF system hs filtrte cpcity of 86 MGD. Ech cell opertes t 20 gllons per squre foot per dy (gfd), 22 minute bckwsh cycles, nd 21 dy clening intervls. Prior to MF tretment, 3 5 mg/l chlormine residul ws mintined to control biologicl ctivity for both the MF nd RO systems. In this regrd, only chlorine ws dded, s mbient mmoni ws sufficient to convert ll dded chlorine to chlormines. The MF filtrte wter hs low turbidity (< 0.2 NTU) nd 15-minute Silt Density Index (SDI) below 3 [14]. Reverse Osmosis The RO system includes the RO trnsfer pump sttion, RO pretretment chemicl ddition, crtridge filtrtion, high pressure membrne feed pumps, RO tretment trins, flushing systems, nd clen-in-plce systems. The RO trnsfer pump sttion pumps MF effluent from the MF filtrte tnk through 10-µm crtridge filters to the RO high pressure membrne feed pumps. Chemicl feeds include sulfuric cid to djust ph from 7.5 to nd proprietry ntisclnt to protect ginst clcium crbonte nd clcium phosphte scling. The RO system consists of 15 RO trins of 5 MGD cpcity ech, for totl of 70 MGD RO permete cpcity. The RO trins operte t 85 percent recovery nd mximum permete flux of 12 gfd. Ech trin includes 150 pressure vessels with 7 RO elements (ESPA2, Hydrnutics, Ocenside, Clif.) per vessel rrnged in 78:48:24 rry. During the first yer of opertion nd continuing through July 2010, the RO system showed generl trend of incresed third stge fouling [14]. Clcium phosphte ws projected to be the primry limiting sclnt t 85 percent wter recovery. However, membrne utopsies indicted tht luminum silictes were fouling the terminl elements. Averge RO influent concentrtions for luminum nd silic were 12 µg/l nd 22 mg/l, respectively levels t which most RO modeling softwre pckges do not predict s being problemtic. Additionlly, one of the diphrgm ntisclnt feed pumps stopped feeding. Hence, significnt loss in specific flux ws observed in July 2008 (Figure 2). Supervisory control nd dt cquisition (SCADA) screens, s well s opertor checks, filed to notice the problem in timely mnner. 12 B-18

178 Clening with 2 percent citric cid solution proved ineffective in restoring membrne flux. Subsequent clening of the third rry using proprietry peroxide-bsed silic clener restored mjority, but not ll, of the lost membrne flux cpcity. OCWD continues to investigte new clening regimes nd threshold inhibitors to increse nd mintin wter production. In ddition, OCWD now vries the feed ph to the RO system on sesonl bsis to help control scle while lso reducing sulfuric cid costs. In the hotter summer months the feed ph is kept ner 6.5 to 6.6 while in the colder winter months, when the feedwter is cooler, the ph is held ner 6.7 to 6.8. UV Oxidtion The UV system utilizes low-pressure, high-output UV lmps (TrojnUVPhox, Trojn Technologies, Ontrio, Cnd) to tret the RO permete. The UV fcility consists of nine lmp ssemblies with ech ssembly designed to tret 8.75 MGD. The UV system is designed to provide 4-log reduction of viruses nd 1.2-log reduction of NDMA. The ddition of 3 mg/l H 2 O 2 upstrem of the UV system provides 0.5-log reduction cpbility for 1,4-dioxne. Post Tretment Lime stbiliztion to protect the conveynce pipelines, Product Wter nd Brrier Pump Sttions, nd ppurtennces from the ggressive deminerlized RO product wter consists of decrbontion with prtil bypss followed by lime ddition. The GWRS utilizes decrbontion system consisting of blowers nd pck towers to prtilly strip the crbon dioxide from the wter. After prtil decrbontion, the UV product is stbilized with hydrted lime. The lime system consists of storge silos with powder hydrted lime (pproximtely 20 mg/l s clcium hydroxide), slurry mix tnks, slurry trnsfer pumps, sturtors, nd polymer ddition system. A 7 percent lime slurry is pumped vi peristltic pumps from the lime storge building to sturtor/clrifier (IDI Accelertor). The sturtor is dosed with n nionic polymer t dose of 1.5 mg/l to id in settling. The superntnt from the sturtor is then dosed into the blend of decrbonted nd non-decrbonted RO permete wter. Finl product wter guidelines include [10]: slightly positive Lngelier Sturtion Index (LSI), Aggressive Index (AI) of ner 12, nd ph between 6 nd 9. The stbilized product wter will then be pumped to the sewter intrusion brrier nd to groundwter rechrge bsins locted 14 miles wy from the plnt site. OCWD opertors experienced problems ssocited with the lime post tretment system [14]. For the first five months of plnt opertion, the lime sturtor ws operted s solids contct clrifier, per design. However, downstrem injection wells receiving the GWRS product wter begn to foul t n incresed rte. Subsequent tests found the finl product wter SDI nd Modified Fouling Index (MFI) vlues were bove 10. The SDI nd MFI should be below 3 to 13 B-19

179 ensure the wter does not hve significnt fouling potentil. OCWD stff determined tht the sturtor would operte better if operted in sludge blnket mode. Figure 3 shows the improvement of the finl product wter SDI nd MFI fter the switch to sludge blnket opertion of the sturtor. In this mode, lyer of lime sludge is llowed to build up in the bottom of the sturtor nd cts s mens to increse the cpture of slowly settble lime solids. Loss of TI flow to RO Figure 2. Specific flux for GWRS over time. TI = threshold inhibitor (i.e., ntisclnt) [14] 14 B-20

180 Chnge to sludge blnket MFI, SDI MFI SDI 0 7/3/2008 6/26/2008 6/19/2008 6/12/2008 6/5/2008 5/29/2008 5/22/2008 5/15/2008 5/8/2008 5/1/2008 4/24/2008 4/17/2008 4/10/ Figure 3. Improvement in SDI nd MFI fter Chnge to Sludge Blnket Opertion [14] Finl Wter Qulity Tble 5 lso shows the finl product wter qulity for the GWRS. For the dt shown, between Februry 2008 nd April 2010, GWRS ws ble to meet or exceed ll regultory requirements. The following generl wter qulity conditions were met: 86 mg/l TDS, 2.4 mg/l TOC, 2.5 mg/l totl nitrogen, 0.01 mg/l totl phosphorous, All trce metls below their respective MCL, No totl or fecl coliforms, All rdiologicl constituents below their respective MCL, nd 0.3 µg/l totl trihlomethnes (TTHMs). Methylene chloride ( mg/l mximum) ws detected in the finl product wter, but ws fr below the MCL of mg/l. NDMA prevlence dt showed n verge concentrtion of 1 ng/l nd mximum vlue of 14 ng/l, bove the 10 ng/l notifiction level. Gemfibrozil, n unregulted PPCP, ws detected in the finl product wter t less thn 1.2 ng/l concentrtions. 15 B-21

181 Specil Studies Pretretment Selection Between 2000 nd 2003, pilot-scle MF nd ultrfiltrtion (UF) evlutions were conducted to pre-qulify pretretment systems for the GWRS [10,15]. Products from severl MF mnufcturers were evluted in order to qulify for prticiption in the project nd to determine operting conditions nd design criteri. Mnufcturers included Siemens Wter Technology (formerly US Filter/Memcor), Pll Corportion, nd GE Zenon (formerly Zenon Environmentl). Further demonstrtion testing of the sme units ws conducted between 2004 nd From these tests, the finl design criteri (e.g., membrne flux, bckwsh intervls, nd clening cycles) were determined. Finl selection of the pretretment process (CS MF, Siemens Wter Technology) ws bsed on competitive bid. RO Membrne Selection Pilot tests were conducted to evlute vrious brckish wter RO elements for use in the GWRS. Thin-film composite polymide RO membrnes from Dow, Koch Membrnes, nd Hydrnutics were evluted in either single-element test skids or multi-rryed RO skid cpble of higher wter recoveries. Through these tests, the Hydrnutics ESPA2 membrne ws selected nd design criteri of 12 gfd nd 85 percent recovery were determined [10]. UV Dose Determintion OCWD conducted pilot-scle investigtions on UV oxidtion of NDMA from secondry treted wstewter derived microfiltered RO permete [16]. The study found tht > 400 mj/cm 2 of UV light ws needed to remove NDMA from 150 ng/l to below the 10 ng/l CDPH Notifiction Level (1.2-log removl). Oxidtive doses of UV light were more thn four times tht necessry for typicl disinfection (80 mj/cm 2 ) for wstewter pplictions [17]. A key finding ws tht UV system hydrulics, rther thn lmp design (e.g., low-pressure high-intensity nd mediumpressure high- intensity), hd profound effect on NDMA reduction. The feed wter to the UV system must be distributed throughout the rection chmber in mnner tht llows mximum contct with ultrviolet light. The rector hydrulics nd lmp spcing design re very much size nd flow dependent, which mkes full-scle testing must to ensure n effective UV system. Further, investigtions found tht for equivlent NDMA reduction, full-scle UV systems used between 40 nd 80 percent less energy compred to pilot-scle systems. This conclusion tht full-scle systems were more efficient in terms of NDMA destruction thn pilot-scle systems ws cused by better system hydrulics [18]. Finl selection of the UV process (Trojn Technologies) ws bsed on competitive bid. Helth Effects Study The OCWD nd OCSD, in conjunction with consultnt, conducted risk ssessment to determine the reltive increse or decrese in potentil dverse public helth outcomes ssocited with the GWRS project [19]. The bsic hypothesis ws the qulity of the recycled wter is expected to be better thn tht of lterntive wter supplies nd the [groundwter] bsin s 16 B-22

182 overll qulity should ctully improve. The purpose of the risk ssessment ws to use quntittive reltive risk ssessment methods to compre pilot plnt effluent representtive of the expected GWRS project effluent with existing wter sources. Study Methodology The study methodology used estimtes of the reltive risks to humn helth ssocited with ech wter source. Wter smpling dt were compiled for GWRS RO permete, Snt An River, Colordo River, nd Stte Wter Project wters. Summry sttistics were compiled for ech source wter nd for ech constituent monitored. Constituents of potentil concern in ech of the source wters were identified s those tht were detected in levels significntly greter thn lbortory or trvel blnks, nd hve ssocited helth bsed criteri, which cn be used to quntify the estimtes of reltive potentil risk. Potentil helth risks ssocited with the exposure scenrio described bove were chrcterized for ech constituent of potentil concern in ech of the rechrge wters. The chrcteriztion of helth risks ws divided into noncrcinogenic helth risks, crcinogenic helth risks, nd risks from microbiologicl contminnts. The hzrd index metric used to clculte non-crcinogenic risk ws defined s follows: Hzrd Index = E 1 /RfD 1 + E 2 /RfD E i /RfD i (2) Where: E i = Exposure level to the ith toxicnt RfD i = Reference dose for the ith toxicnt Ei/RfD i = Hzrd Quotient for the ith toxicnt Crcinogenic risks were estimted s the incrementl probbility of n individul developing cncer over lifetime s result of exposure to potentil crcinogen. The numericl estimte of excess lifetime cncer risk ws clculted s follows: Risk (probbility/lifetime) = Chemicl Intke (mg/kg/dy) x Slope Fctor (mg/kg/dy) -1 (3) Cncer slope fctors with 95 th percentile confidence limits were bsed on experimentl niml dt nd limited epidemiologicl studies, when vilble. A liner non-threshold mthemticl model for low-dose extrpoltion ws used to clculte numericl cncer potency vlues. Tble 6, Tble 7, nd Tble 8 show the non-crcinogenetic nd crcinogenic risk fctors clculted for both GWRS effluent, Snt An River, nd imported surfce wters. Note: neither Ei/RfD i nor the slope fctors were provided in the originl report. Hence, the dt contined in Tbles 6 8 cnnot be confirmed. Risks Associted with Non-Crcinogenic Helth Effects Tble 6 nd Tble 7 provide summries of non-crcinogenic risks ssocited with direct consumption of GWRS product wter, nd Snt An River wter nd imported wters, respectively. Through the hzrd index method, the non-crcinogenic helth risk for drinking 17 B-23

183 GWRS product wter (0.14) ws lower thn either Snt An River (0.65) or imported wter (0.51). Risks Associted with Crcinogenic Helth Effects Tble 8 provides comprison of estimte crcinogenic risk for individuls drinking either GWRS product wter or Snt An river wter. The generl findings were: The estimted crcinogenic risks ssocited with direct consumption of GWRS product wter ws lower thn tht ssocited with direct consumption of either Snt An River or imported wter; Although the levels of rsenic in ll three source wters re below the existing nd the proposed regultory levels, rsenic is the constituent tht ccounts for the mjority of the risk ssocited with continued relince on the Snt An River; At n (ssumed) mximum concentrtion of 20 ng/l, NDMA would present more crcinogenic risk thn ny other constituent of concern identified in GWRS product wter; nd The presence of rsenic is the dominnt risk fctor ssocited with blends in either wter source. Risks Associted with Microbiologicl Contminnts GWRS product wter ws projected to present much lower risk thn existing rechrge wters from bcteri, prsites, nd viruses, provided tht ll unit processes in the tretment fcility were fully opertionl nd operted properly. This conclusion ws bsed on the expected pthogen levels in the rw wstewter influent (generlly 10 3 pfu/l or less), the documented virus removl cpbilities of the GWRS integrted tretment trin, previously reported removl of prsites through n AWT tretment trin, nd the fct tht ultrviolet disinfection would be prt of the integrted tretment trin [19]. Study Conclusions The risk ssessment study concluded tht the reltive helth risk ssocited with the GWRS project ws less thn or equl to tht ssocited with the current surfce spreding opertions. The cvets to this conclusion were: The concentrtion of NDMA does not exceed 20 ng/l, s used in the risk ssessment; The concentrtion of the remining non-microbil constituents do not increse more thn fctor of five bove tht used for the risk ssessment; nd No degrdtion in wter qulity being observed bsed on continul monitoring of the GWRS product wter. Constituents of Emerging Concern Monitoring OCWD conducted severl projects to evlute the effectiveness of dvnced wter tretment technologies to remove PPCPs nd EDCs from secondry or tertiry treted wstewter effluents [20,21]. The objectives of these projects vried, but the min thrust ws to gin better 18 B-24

184 understnding of PPCP nd EDC removl rtes cross dvnced wter tretment processes for indirect potble reuse. Bench-scle work developed model whereby specific PPCP nd EDC removl rtes cross RO nd NF membrnes could be estimted priori. This theoreticl model ws bsed on complex physico-chemicl interctions between the compounds of interest nd membrne properties. The following key solute prmeters were identified to primrily ffect solute rejection: moleculr weight (MW), moleculr size (length nd width), cid disssocition constnt (pk ), hydrophobicity/hydrophilicity (log K ow ), nd diffusion coefficient (D p ) [22]. Key membrne properties ffecting rejection tht were identified include moleculr weight cut-off (MWCO), pore size, surfce chrge (mesured s zet potentil), hydrophobicity/ hydrophilicity (mesured s contct ngle), nd surfce morphology (mesured s roughness). Full-scle wter qulity monitoring indicted tht GWRS s MF-RO-AOP tretment trin produced wter of sufficient qulity to meet ll Stte nd Federl primry drinking wter stndrds (Tble 5). With the exception of gemfibrozil, ll PPCPs nd EDCs detected in the MF feedwter were reduced to levels below method detection limits in the finl product wter. Arsenic Leching Per OCWD s permit, blend of 75 percent reclimed wter nd 25 percent imported drinking wter ws mintined between 2008 nd Strting in 2010, this provision ws lifted s OCWD ws ble to show no degrdtion of the quifer wter qulity ws cused by GWRS opertions t the 75 percent blend. However, shortly fter going to 100 percent reclimed wter, higher thn expected rsenic levels were observed in severl monitoring wells ner the Krmer nd Miller spreding grounds. While the source of the rsenic ws not identified, it ws believed tht the incresed quntity of reclimed wter my hve contributed to the dissolution of rsenic in the bsin soil. OCWD hs since returned to the 75:25 blend nd reduced the product wter ph from 9.0 to 7.5 until the source of the elevted rsenic could be better understood [6]. West Cost Bsin Brrier Project The Edwrd C. Little Wter Recycling Fcility, operted by West Bsin Municipl Wter District (WBMWD), consists of three seprte tretment processes currently designed to produce totl of up to 50 MGD of vrious qulity recycled wter. This report will focus solely on the West Cost Bsin Brrier Project (herefter referred to s the Brrier plnt), n dvnced purifiction fcility designed to provide recycled wter for injection into sewter intrusion brrier. The Brrier plnt ws upgrded to 12.5 MGD in 2006 nd consists of newly instlled MF, RO, nd dvnced oxidtion (UV nd hydrogen peroxide) systems [23]. Source Wter The source wter for the Edwrd C. Little Wter Recycling Fcility is secondry effluent from the Hyperion Tretment Plnt tht is owned nd operted by the City of Los Angeles. Industril wstewter sources rnges from 10 to 15 percent of Hyperion s influent flow [24]. Primry tretment is provided by sedimenttion tnks in order to remove 85 percent of orgnic nd 19 B-25

185 inorgnic solids from rw wstewter. Primry effluent then treted through high-purity oxygen ctivted sludge bsins followed by secondry clrifiction tnks where settling of the biomss occurs. The Brrier plnt uses side strem of the secondry treted effluent prior to being dischrged into the Snt Monic By s the feed. Sodium hypochlorite is dded to this wter to generte between 3 nd 5 mg/l chlormines prior to the MF pretretment. Tble 5 provides summry of the influent wter qulity dt for the Brrier plnt. These dt were tken from the City of Los Angeles 2009 Annul Monitoring Report for the Hyperion Tretment Plnt [25]. Brrier plnt influent wter qulity dt reveled the secondry treted wter contined high levels of mmoni (41 mg/l NH 3 -N verge nd 44 mg/l NH 3 -N mximum), turbidity (9 NTU vg. nd 14 NTU mx.), TOC (17 mg/l vg. nd 18 mg/l mx.), nd totl suspended solids (TSS; 18 mg/l vg. nd 25 mg/l mx.). Of the permit regulted trce orgnic compounds, most were below the MDLs nd ll were below MCLs. NDMA ws not detected in the Hyperion Tretment Plnt effluent; however the MDL ws only 0.5 µg/l. Hyperion effluent did contin miniml levels of gross lph (3.57 pci/l vg. nd 5.83 pci/l) nd gross bet (9.4 pci/l vg. nd 12.7 pci/l mx.) emitters. No fecl or totl coliform dt were reported. Pretretment The current MF units consist of Siemens CMF-S with 0.2 µm polypropylene membrnes. The MF system opertes t design flux of 21 gfd nd recovery of 91 percent. Reverse Osmosis RO is two-stge 72:36 rry, with seven 8-inch dimeter by 40-inch long membrne elements (ESPA2, Hydrnutics, Ocenside, Clif.) per vessel. The RO trin opertes t 85 percent recovery t flux rte of 12 gfd. Chemicl feeds to the RO influent include sulfuric cid to lower the ph to 6.4 nd ntisclnt to protect ginst minerl scling. UV Oxidtion The UV system (TrojnUV Phox TM, Trojn Technologies) chieves oxidtion/disinfection vi combintion of direct photooxidtion using low pressure high intensity mlgm lmps tht emit UV dose of greter thn 115 mj/cm 2 t pproximtely 254 nnometers. Three prts per million (ppm) hydrogen peroxide re lso dded for indirect photooxidiztion from highly oxidtive OH rdicls. Post Tretment Product wter from the UV/Peroxide AOP is decrbonted, nd, finlly, pproximtely 33 mg/l lime is dded to djust the ph to pproximtely 8, nd dditionl sodium hypochlorite is dded prior to distribution to brrier injection wells. 20 B-26

186 Finl Product Wter Qulity Tble 5 lso shows the finl product wter qulity for the Brrier plnt [26]. For the dt shown for 2007 nd 2009, the Brrier plnt ws ble to meet or exceed ll regultory requirements. The following generl wter qulity conditions were met: 83 mg/l TDS, 0.3 mg/l TOC, 3.2 mg/l totl nitrogen, All trce metls below their respective MCLs, No totl or fecl coliforms, All rdiologicl constituents below their respective MCLs, nd 1.26 µg/l TTHMs. Methylene chloride (0.001 mg/l mx.) ws detected in the finl product wter, but ws fr below the MCL of mg/l. NDMA dt showed n verge concentrtion of 6.4 ng/l nd mximum vlue of 20 ng/l bove the 10 ng/l CDPH Notifiction Level. Of the EDCs nd PPCPs monitored, only bisphenol-a (5 ng/l vg. nd 17 ng/l mx.) nd ethinyl estrdiol (2.6 ng/l mx.) were detected bove the MDLs. Specil Studies Pretretment Selection WBMWD considered three mnufcturers to supply MF tretment for the Brrier plnt. The three mnufcturers were Siemens Wter Technology (formerly US Filter/Memcor), Pll Corportion, nd GE Zenon (formerly Zenon Environmentl) [27]. Finl selection of the pretretment process (CMF-S MF, Siemens Wter Technology) ws bsed on competitive bid. RO Membrne Selection No dt on membrne selection were found. Bsed on personl communictions with WBMWD stff, RO membrnes were selected bsed on OCWD s GWRS results [28]. UV Oxidtion Selection UV oxidtion in tndem with H 2 O 2 ddition ws studied to evlute NDMA removl from post- RO wter [27]. The min objectives of the UV studies were to: 1. Evlute both low- nd medium-pressure UV lmps in terms of NDMA removl (with nd without H 2 O 2 ), energy consumption, nd mintennce, nd spce requirements; nd 2. Exmine NDMA re-formtion potentil in post chlorinted RO wter. 21 B-27

187 Mjor conclusions from these studies were: NDMA removl efficiency ws not predicted on lmp design (i.e., low- or mediumpressure lmps), NDMA ws ble to be reduced from 200 ng/l to less thn 2 ng/l on relible bsis. It should be noted tht WBMWD did not report specified UV dose for NDMA destruction, only n pproximte energy consumption ( kwh/1000 gllons for medium-pressure lmps nd kwh/1000 gllons for low-pressure lmps), UV efficcy for NDMA removl not dependnt on H 2 O 2 concentrtion, Simulted distribution testing did not indicte tht NDMA would reform once wter ws treted with UV nd subsequently chlorinted with two-dy contct time. Technicl dvisory pnel recommended to CDPH (formerly Cliforni Deprtment of Helth Services) tht H 2 O 2 ddition be continued to provide n dded level of protection ginst s yet unidentified constituents of emerging concern. Constituents of Emerging Concern Monitoring WBMWD, in conjunction with Seprtion Processes, Inc., conducted study to evlute removl rtes of trce-orgnic compounds commonly found in secondry treted wstewter through the full-scle dvnced wter purifiction processes (MF, RO, nd UV plus hydrogen peroxide) [29]. A totl of 158 trce-orgnic compounds were nlyzed in this study, nd 23 were detected in levels suitble to determine removl rtes s shown in Tble 9. The compounds detected included phrmceuticls, trihlomethnes, endocrine disrupting compounds, plsticizers, solvents, herbicides, nd industril byproducts. Overll, MF ws less effective thn RO nd UV for removl of the selected orgnic compounds shown in Tble 9. RO cn effectively remove dichlorocetic cid (DCAA), trichlorocetic cid (TCAA), bromoform, methyl-tert-butyl ether, toluene, 1,4 dioxne, nd dlpon. UV demonstrtes better performnce thn RO for removl of 1,4-dichlorobenzene (pdichlorobenzene), dibromochloromethne, dibromomethne, tetrchloroethene, nd bromochloromethne. It ppers tht none of processes cn effectively remove methylene chloride nd bromochloromethne. These results were similr to previous pilot-scle testing performed by WBMWD [30]. Almitos Brrier Recycled Wter Project The Almitos Brrier Recycled Wter Project ws undertken by the Wter Replenishment District of Southern Cliforni (WRD) to supplement the imported wter supply used to protect drinking wter quifers in the Centrl Bsin of Los Angeles County. As such, the Leo J. Vnder Lns Advnced Wter Tretment Fcility ws commissioned in The 3-MGD design cpcity plnt trets disinfected tertiry effluent from the Los Angeles County Snittion Districts (LACSD s) Long Bech Wter Reclmtion Plnt (LBWRP) with MF pretretment, followed by RO nd UV. The Advnced Wter Tretment Fcility is designed to produce 22 B-28

188 recycled wter tht meets the CDPH requirements for indirect potble reuse using intermedite groundwter storge. Source Wter The source wter for the Leo J. Vnder Lns Advnced Wter Tretment Fcility is disinfected tertiry effluent from the LBWRP. The originl source wter for the LBWRP is predominntly comprised of residentil nd commercil wstewter, with only 5 percent of the flow of industril origin. There were no known chemicl, phrmceuticl, photogrphic, or biologicl production fcilities within the LBWRP s ctchment re [31]. Primry tretment involves settling tnks to remove grit nd debris. Secondry nd tertiry tretments include ctivted sludge ertion tnks to reduce biologicl oxygen demnd (BOD) nd multi-medi filtrtion nd chlorintion for pthogen nd virus inctivtion, respectively. Tble 5 shows influent wter qulity dt for the Leo J. Vnder Lns fcility (i.e., effluent from the LBWRP) [32,33]. The finl filtered effluent from the LBWRP is permitted s Title 22 qulity recycled wter for non-potble (e.g., irrigtion nd industril) uses. Leo J. Vnder Lns verge (mximum) influent wter qulity dt reveled the tertiry treted wter contined 1.11 mg/l mmoni s nitrogen (1.72 mg/l NH 3 -N), 0.76 mg/l (5.8 mg/l) TSS, 0.53 NTU (0.85 NTU) turbidity, 5.85 mg/l (7.71 mg/l NO 3 -N) nitrte s nitrogen, nd vrious trce metls. The mjority of trce orgnic compounds were below the MDLs. However, NDMA verged 470 ng/l with mximum vlue of 1,400 ng/l. Rdiologicls (e.g., gross lph, gross bet, nd urnium) were detected in the influent wter, though below their respective MCLs. No totl or fecl coliforms were detected in the source wter to the Leo J. Vnder Lns fcility. Pretretment The selection of pretretment equipment ws pre-qulified by WRD engineers through review of OCWD nd WBMWD s pilot- nd demonstrtion-scle test dt. Of the two pre-qulified vendors (UF Filter/Memcor nd Pll Corportion), the Pll MF system (module model #USV- 6203, Pll Corportion, Port Wshington, NY) ws chosen through competitive bid process. The 3.53 MGD MF system consists of outside-in hollow fiber membrnes with 200 MF modules rrnged in 8 rcks (25 modules per rck). The design operting flux for the MF system is pproximtely 33 gfd on 24-hour bsis. The MF system does not hve feed pumps, but uses modulting vlves to regulte the pressure from the LBWRP distribution system ( psi) to filter the tertiry treted wstewter [34]. Chlorine ws fed prior to the MF unit to protect ginst biofouling. The chlorine combined with mbient mmoni to form chlormines, with the chlormine residul being mintined throughout the MF process. Reverse Osmosis The RO design criteri were developed by the WRD s consultnts (Cmp Dresser nd McKee Inc., nd Seprtion Processes, Inc.). RO tretment consists of single 3.0-MGD 2:1 rry system designed to operte t 10 gfd membrne flux, 85 percent feed wter recovery nd 90 percent opertionl relibility. Ech of the 72 first-stge nd 36 second-stge vessels house 23 B-29

189 seven 8-inch dimeter by 40- inch long spirl wound membrne elements (ESPA2, Hydrnutics, Ocenside, CA). Chemicl feeds to the RO influent include sulfuric cid nd ntisclnt to protect the system ginst minerl scling. UV Oxidtion A UV system (Model 30AL50, TrojnUVPhox, Trojn Technologies, Ontrio, Cnd) ws dded downstrem of the RO system to oxidize NDMA found in the LBWRP effluent wter. An engineering study conducted by the WRD identified UV oxidtion ws the preferred method for controlling NDMA [35]. WRD required tht the UV system be ble to reduce NDMA concentrtions from n verge of 420 ng/l to below 10 ng/l the CDPH Notifiction Level ( 1.6-log reduction). Dt from OCWD nd WBMWD were sited showing NDMA ws rejected by RO membrnes by pproximtely 50 percent. The mjor ssumption in the UV design ws tht n estimted verge of 600 ng/l NDMA in the Leo J. Vnder Lns influent would conservtively experience 30 percent removl cross the RO system; hence the 420 ng/l NDMA verge vlue ws used. Thus, t 2,000 gllons per minute (gpm) nd UV light trnsmittnce (UVT) of 95 percent, the UV dosge to chieve 1.6-log photolysis of NDMA ws estimted to be 149 mj/cm 2. These design criteri were developed through pilot testing by the UV mnufcturer nd WRD [35]. Post Tretment Post tretment of the RO permete includes pcked-tower decrbontion step to remove excess crbon dioxide nd ph djustment to 8.7 with sodium hydroxide. Finl trget ph nd LSI once permete wter is blended with surfce wter prior to injection is 8.1 nd 0.1, respectively [31]. Finl Product Wter Qulity Tble 5 lso shows the finl product wter qulity for the Leo J. Vnder Lns Advnced Wter Tretment Fcility. For the dt shown, between Jnury 2008 nd December 2009, the Leo J. Vnder Lns plnt ws ble to meet or exceed ll regultory requirements. The following generl wter qulity conditions were met: 72 mg/l TDS, 0.48 mg/l TOC 1.6 mg/l totl nitrogen, All trce metls below their respective MCLs, No totl or fecl coliforms, All rdiologicl constituents below their respective MCLs, nd 8.7 µg/l TTHMs. NDMA dt showed n verge concentrtion of 4.3 ng/l nd mximum vlue of 6.4 ng/l, below the 10 ng/l Notifiction Level. Gemfibrozil, n unregulted PPCP, ws detected in the finl product wter t less thn 1.3 ng/l. 24 B-30

190 Specil Studies Improving System Performnce Between 2003 nd 2008, the Leo J. Vnder Lns plnt ws not ble to operte continuously t design conditions (85 percent wter recovery, 10 gfd flux, nd 3.0 MGD cpcity) [34]. Despite running t lower operting flux (8 9 gfd) nd wter recovery rtes (81 percent), the plnt experienced excessive membrne fouling, which led to 2 3 week chemicl clening intervls. A consultnt evluted the Leo J. Vnder Lns plnt s operting dt nd determined the following: The MF system ws operting within design prmeters (turbidity 0.15 NTU, SDI 3 5 units, nd percent fiber brekge); Primry RO minerl sclnts (clcium crbonte nd clcium phosphte) were within design limits; The mjor cuse of membrne fouling ws byproduct of elevted luminum ( µg/l) in the plnt influent, most likely cused by the use of luminum sulfte cogultion t the LBWRP. The residul luminum precipitted on the RO membrnes s luminum hydroxide, luminum phosphte, or luminum silicte. Sequentil cidbse chemicl clenings were ble to restore membrne performnce. LBWRP subsequently discontinued lum ddition nd RO membrne performnce improved, s evidenced by reduced rtes in incresing pplied feed pressure from initilly 10 psi/dy to 3 psi/dy. Biofouling my lso hve been minor cuse of membrne fouling. Sodium bisulfite ws fed t the RO influent to quench the chlormine residul to protect the membrnes ginst membrne oxidtion. The sodium bisulfite feed ws eliminted in August After the elimintion of lum fed t the LBWRP nd sodium bisulfite feed t the RO influent, the RO system ws ble to meet design set points. The most criticl fctor ws the discontinution of the lum feed t the LBWRP. Western Austrli A reserch consortium comprised of vrious governmentl entities (Government of Western Austrli s Deprtment of Helth, Deprtment of Wter, Deprtment of Environment nd Conservtion, Ntionl Mesurement Institute, CSIRO, nd the Chemistry Centre of Western Austrli), privte compny (the Wter Corportion), nd two universities (University of Western Austrli, Curtin University of Technology) conducted three-yer study to determine the fesibility of ugmenting drinking wter supplies in Western Austrli through groundwter replenishment [36]. The reserch ws conducted to determine the fesibility of using MF nd RO tretment to provide wter to supplement wter supplies through groundwter injection. While UV tretment ws recommended for future studies, no UV testing ws prt of this report. The ims of the project were to: 25 B-31

191 Chrcterize the microbil nd chemicl constituents of the lrge metropolitn wstewter tretment plnts (WWTPs) tht could serve s the source for potentil wter recycling plnts. Plese note tht while three WWTPs source wters were studied in the report, this document will only report on two of them (Woodmn Point nd Beenyup), s these plnts hd MF-RO dt ssocited with them. Anlyze the permete to ssess the performnce of MF followed by RO tretment t the Kwinn Wter Reclmtion Plnt (WRP) fed by Woodmn Point WWTP nd the specilly constructed Beenyup pilot plnt, to consistently produce wter meeting helth nd environmentl requirements. Use the reserch results to develop nd refine helth nd environmentl guidelines. Source Wter The Perth Metropolitn wstewter system comprises minly with urbn nd commercil sources, with low industril lodings. The three min wstewter tretment plnts re Beenyup, Subico, nd Woodmn Point WWTPs. The 36-MGD Beenyup WWTP serves the north of the city, which is minly residentil. The Woodmn Point WWTP trets up to 34 MGD nd serves the south metropolitn region. Source wter for the Woodmn Point WWTP comes from residentil, non-residentil (mjority from food mnufcture nd processing or resturnt industries), industril (six percent), nd medicl wste (less thn percent). The Beenyup WWTP process trin includes screening, grit removl, ctivted sludge tretment with erted nd noxic zones (designed for denitrifiction) nd clrifiction. The Woodmn Point plnt uses screening, grit removl nd ctivted sludge tretment vi sequencing btch rector. This process conducts ctivted sludge tretment in btches tht re subject to ertion nd non-ertion periods (designed for nitrifiction nd denitrifiction) followed by decnting the clrified wstewter. The Subico plnt will not be discussed further in this document s the Subico plnt hs no MF or RO fcilities ssocited with it. Tble 5 shows the combined influent wter qulity dt for the Beenyup pilot plnt nd Kwinn WRP tken between 2005 nd 2008 [36]. Individul WWTP dt, where vilble, re noted in Tble 5 through vrious superscripts. Both the Woodmn Point (source wter for the Kwinn WRP) nd Beenyup WWTPs hve prtilly nitrified effluent. As such, the verge influent wter qulity dt for the secondry treted effluents were 4.48 mg/l NH 3 -N, 17.9 mg/l totl TSS, 8.68 NTU turbidity, 4.4 mg/l NO 3 -N, nd vrious trce metls. The mjority of trce orgnic compounds were below the MDLs. However, NDMA ws bove the CDPH 10 ng/l Notifiction Level with n verge of 16 ng/l nd mximum vlue of 43 ng/l. Low levels of gross lph nd gross bet emitters were detected in the influent wter, though below their respective MCLs. No totl or fecl coliforms dt were reported. However, enterococcus nd thermotolernt coliforms were present in ll smples tken from the Beenyup WWTP. Enteric virus nd coliphges, while not quntified, were lso regulrly detected in Beenyup WWTP effluent. 26 B-32

192 Pretretment Pretretment for the full-scle Kwinn WRP involves initil 2-mm course screening, chlormintion (1 2 mg/l), ph djustment (ph ), nd hollow-fiber, outside-in, polypropylene-membrne MF (Memcor CMF S10T, Siemens). Antisclnt (PC-191T, Nlco Compny, Nperville, Illinois) ws dosed prior to RO membrne tretment. Pretretment for the continerized Beenyup pilot plnt consisted of 1-mm course screening, followed by pressurized MF using polyvinylidene fluoride (PVDF) membrnes (Memcor CMF-L 6L10V, Siemens). Chemicl feeds included mmoni nd sodium hypochlorite to form 1 2 mg/l chlormines, sulfuric cid to mintin n RO feed ph of 6.0, nd ntisclnt (Hydrex 4101, Veoli Wter Solutions & Technologies, Pyrmont, New South Wles, Austrli) for minerl scle control. Reverse Osmosis RO tretment for Kwinn WRP consisted of 8-in wide x 40-in long polymide membrnes (BW FR, Dow Flimtec, Minnetonk, Minn.) designed for pproximtely 9 gfd t 70 percent wter recovery. The pilot-scle RO system t the Beenyup WWTP utilized 4-in long x 40-in long polymide RO membrnes (ESPA2, Hydrnutics, Ocenside, Clif.) operted t 9.3 gfd between percent wter recovery. UV Oxidtion During this study period, no UV tretment ws conducted by either plnt. However, UV oxidtion (200 mj/cm 2 ) ws used t the Beenyup groundwter replenishment project in lter testing [37]. No UV dt re vilble t this time. Post Tretment Post tretment for the Kwinn WRP ws sodium hypochlorite nd sodium hydroxide to rise ph. No chlorine or ph set points were specified in the report. No post tretment ws conducted t the Beenyup pilot plnt. Finl Product Wter Qulity Tble 5 lso shows the finl product wter qulity for the Beenyup pilot plnt nd Kwinn WRP. For n bbrevited list of chemicl constituents for the Beenyup pilot plnt, see Tble 10. For the dt tken between 2005 nd 2008, both plnts were ble to meet or exceed ll regultory requirements. The following generl wter qulity conditions were met: 5 mg/l TDS (dt tken prior to post stbiliztion), 0.35 mg/l TOC 1.0 mg/l totl nitrogen, All trce metls were below their respective MCLs, No detectble pthogens or viruses, All rdiologicl constituents were below their respective MCLs, nd 27 B-33

193 8.7 µg/l TTHMs. NDMA dt showed n verge concentrtion of 4.5 ng/l, but hd mximum vlue of 30 ng/l bove the 10 ng/l CDPH Notifiction Level. Mny orgnic chemicls tht were detected in wstewter were lso reported in t lest one post-ro wter smple. Acrylonitrile ws detected in 83 percent of the post-ro smples followed by 1,4-dioxne (29 percent), zobenzene (24 percent) nd butylbenzylphthlte (14 percent). The following nlytes were only mesured in one smple from Kwinn WRP: 4-chlorophenoxybenzene, 4- bromophenoxybenzene, hexchlorobenzene, nd MTBE. Aprt from MTBE (1.66 µg/l), the highest medin concentrtions were 0.12 µg/l for 1,4-dioxne nd 0.13 µg/l for crylonitrile. The medin concentrtion of ll other chemicls ws lower thn 0.04 µg/l. It ws uncler s to why MBTE concentrtion in the post-ro smple ws higher thn tht found in the corresponding wstewter smple. For crylonitrile, the medin concentrtion in post-ro wter (0.13 µg/l) ws higher thn tht in secondry wstewter (0.04 µg/l), nd percentge detections in post-ro wter (83 percent) were lso higher thn in secondry wstewter (50 percent). Of the 36 phrmceuticl compounds nlyzed, only clofibric cid (1.6 ng/l), dizepm (26.4 ng/l), nd nproxen (15 ng/l) were detected in the post-ro effluent. In should be noted tht these dt were tken without ny dditionl UV/peroxide tretment [36]. Specil Studies Risk Quotients Figure 4 shows the three-tiered chemicl risk ssessment pproch used by the Western Austrli government to estblish wter qulity guidelines for indirect potble reuse within the region [37]. Risk quotients (RQs) indictors of potentil helth risks were ssigned to ech constituent of concern. Constituents of concern included trce metls, rdiologicls, pesticides, DBPs, N-nitrosmines, voltile orgnic compounds (VOCs), miscellneous orgnics (e.g., phenols, dioxins, furns, polychlorinted biphenyls [PCBs], 1,4-dioxne, nd MTBE), PPCPs, nd estrogenic hormones. RQs were clculted by dividing the mesured concentrtion (MC) of detected contminnt by either its guideline vlue for regulted compound (Tier 1), helth vlue for unregulted chemicls with toxicity informtion (Tier 2), or threshold of toxicologicl concern vlue for unregulted chemicls without toxicity informtion (Tier 3). Wter qulity guideline nd helth vlues were bsed on dt found in Austrlin Drinking Wter Guidelines, World Helth Orgniztion, USEPA, Title 22: CCR, nd Europen Union wter qulity regultions. When dt were lcking on toxicologicl significnce, the Western Austrli government consulted with Austrli s Interntionl Agency on Cncer Reserch, Integrted Risk Informtion System, Risk Assessment Informtion System, nd Ntionl Toxicology Progrm [36]. An RQ less thn 1 implies low helth risk [36]. RQs before nd fter RO were clculted using medin nd mximum concentrtions (RQ medin nd RQ mx ). 28 B-34

194 For ll rdiologicls, VOCs, miscellneous orgnics, PPCPs, nd estrogenic hormones mesured, RQs were below 1 indicting low helth risks for these compounds. The trce metls luminum nd nickel nd pesticides trzine nd propiconzole hd RQs equl to 1 ; otherwise ll other RQs for compounds in these two clsses were below 1. The highest RQs bsed on mesurble constituents of concern were the DBPs bromochlorocetldehyde (RQ mx = 1.4) nd dibromocetldehyde (RQ mx = 1.3), nd the N-nitrosomines NDMA (RQ mx = 3), N-nitrosomorpholine (RQ mx = 2.2), N-nitrosodi-n-bultyldimine (RQ mx = 2.1), N-nitrosopiperidine (RQ mx = 1.5), nd N-nitrosodi-n-propylmine (RQ mx = 1.4) [36]. It is worth noting tht the concentrtions of DBPs observed in the post-ro wter were pproximtely 10 to 100 times lower thn typicl concentrtions in Perth drinking wter [36]. The uthors did recommend further studies on N-nitrosmine precursor removl, post-ro tretment (e.g., UV oxidtion), nd nturl degrdtion in the environment be conducted. The uthors lso suggested tht NDMA be used s chemicl indictor to guge tretment efficcy (see Chemicl Indictors of Tretment Performnce below) [36]. Virl Chllenges Two chllenge tests were undertken t Beenyup pilot plnt using the coliphge MS2 s n indictor of enteric viruses to ssess the cpcity of the RO membrnes to exclude such viruses. The results showed tht the RO membrnes lone were ble to chieve t lest 4-log removl (i.e., percent removl) of viruses. However, the uthors cutioned tht integrity monitoring ws vitl to ensure tht rejection of viruses, bcteri, nd pthogens ws mintined. Tble 11 shows the log-removl/inctivtion credits dopted for the Beenyup Advnced Wter Tretment Plnt in Western Austrli [37,38]. These performnce criteri were dopted bsed on literture vlues, s well s pilot- nd full-scle dt where pplicble. As shown in Tble 11, the proposed Beenyup Advnced Wter Tretment Plnt would exceed removl/inctivtion credits for bcteri, viruses, nd protozo. Chemicl Indictors of Tretment Performnce The key outcome of this reserch ws the identifiction of chemicl indictors of RO tretment performnce nd recycled wter qulity indictors relevnt for Western Austrli. The results from this project were nlyzed to derive group of indictors pproprite for monitoring chemicl removl for different chemicl groups by MF followed by RO. Rejection of chemicl contminnts by MF followed by RO is relted to interctions between RO membrne chrcteristics, filtrtion operting conditions, nd compound properties. While chemicls of low moleculr weight nd high polrity re expected to be poorly rejected by the membrnes, the presence of ny of the chemicl indictors with lrge moleculr weight in the post-ro wter will indicte filure of the tretment system. Of the 396 compounds investigted in the study, 25 were determined to hve percentge detections in post-ro wter greter thn 25 percent. Eight of these compounds were disinfection 29 B-35

195 by-products (seven hlogented DBPs, one N-nitrosmine, nd one inorgnic disinfection byproduct), while six were metls or metlloids, four were VOCs, nd the remining compounds were from the clsses of complexing gents, phenols, or miscellneous chemicls. Only the N- nitrosmines pose potentil concern from helth point of view. Eight compounds hd higher percentge detection in post-ro thn in secondry wstewter, nd this ws ttributed to contmintion (e.g., toluene), formtion during chlormintion (e.g., hlomethnes), or unintentionl ddition during the MF followed by RO process (e.g., crylonitrile, chlorte). These constituents demonstrte tht chlormintion procedure, membrne mterils, nd ntisclnt chemicl usge lso need to be considered s potentil sources of chemicls in post-ro wter. Tble 12 shows proposed surrogtes to be used in guging the dy-to-dy opertion of the overll tretment process [36]. Surrogtes were chosen for their ese in monitoring through the use of clibrted on-line probes. Specific surrogtes include dissolved oxygen, turbidity, conductivity, TOC, UV light intensity, nd ph. Tble 13 presents the selected chemicl indictors of MF followed by RO tretment performnce, s identified by the Western Austrlin reserch tem [36]. The chemicl indictors cover chemicl groups with different: Moleculr weights (rnged from 10.8 to 296 g/mol), Hydrophobicity properties (log K ow rnged from to 3.4), nd Acidic/bsic chrcteristics (pk rnged from 2.13 to 10.4). Indictor chemicls were selected bsed on the following criteri: Commonly detected in secondry wstewter (most more thn 90 percent of the time); Detected t higher concentrtions thn other chemicls of the sme group. If more thn one compound ws commonly detected in secondry wstewter t similr concentrtions, the one with the lower percentge of rejection ws selected s it is considered more sensitive to ssess the performnce of the tretment; Prtilly removed under norml operting conditions. Indictor compounds tht re prtilly removed by the tretment process re more sensitive indictors of system filure thn poorly removed compounds; Hve chrcteristics tht cn be linked to predominnt removl mechnism (e.g., filtrtion, dsorption, or oxidtion), becuse different tretment processes trget different properties; Be present in concentrtions tht re representtive of the broder clss of compounds nd tht re sufficiently high to determine meningful degree of reduction through unit process or sequence of processes; nd Be quntifible using n estblished, nd preferbly ccredited, nlyticl method. 30 B-36

196 Tble 14 shows dditionl compounds tht my provide chemicl indictors of recycled wter qulity. Recycled wter qulity indictors hve the purpose of demonstrting sfety of recycled wter with respect to specific chemicl groups, nd hence provide dditionl confidence beyond tretment performnce indictors found in Tble 13. This cn be prticulrly importnt for some chemicl groups such s hormones nd pesticides for which no chemicl ws selected s tretment performnce indictor. Is Drinking Wter Stndrd Avilble for the Compound? Yes No TIER 1: RQ = MC/GV Is Toxicity Dt Avilble? Yes No TIER 2: RQ = MC/HV TIER 3: RQ = MC/TTC Flow Chrt shows three tiered pproch, with RQ =risk quotient, MC = mesured concentrtion, GV = guideline vlue, HV = helth vlue, nd TTC = threshold of toxicologicl concern Figure 4. Chemicl Risk Assessment Approch for Western Austrli. Adpted from [37] Occoqun Reservoir, Virgini The Occoqun Reservoir is component in wter supply system tht currently serves over 1.7 million residents of Northern Virgini [39]. In the 1960s, the Occoqun wtershed begn trnsforming from lrgely rurl to predomintely urbn/suburbn region. This rpid growth resulted in deteriortion of wter qulity in the eleven-billion-gllon (34,000-cre-feet) Occoqun Reservoir. The reservoir s wter qulity degrdtion resulting in [40]: 31 B-37

197 Frequent nd intense lgl blooms; Periodic episodes of tste nd odor in the finished drinking wter; Low dissolved oxygen levels; Periodic fish kills; nd Genertion of hydrogen sulfide in the lower reches of the reservoir. Initil studies showed tht the wter qulity deteriortion in the reservoir ws cused by substndrd wstewter dischrges from eleven secondry wstewter tretment plnts nd nonpoint sources of pollution. The Upper Occoqun Service Authority (UOSA) plnt replced the eleven smll secondry tretment plnts in the region. Unlike the previous four cse studies, the UOSA plnt ws designed to reduce the nutrient loding in the surfce wters feeding the Occoqun Reservoir, rther thn ugmenting groundwter supplies. More specificlly, the UOSA plnt ws designed to: Prevent the relese of sediment bound phosphorus; Reduce the relese of mmoni from reservoir sediments; Prevent the reduction of sulfte to sulfide in the bottom lyers of the reservoir; Possibly prevent the relese of mngnese (II) from sediments; nd Mintin green lge nd ditoms species dominnce nd preventing the prolifertion of less desirble blue-green lge. The subsection below describes the dvnced wter tretment system used to improve the wter qulity of the Occoqun Reservoir. The following subsection describes the drinking wter tretment plnts (WTPs) operted by the Firfx County Wter Authority (FCWA) tht use the Occoqun Reservoir s the source wter. Prior to 2007, both the Lorton nd Occoqun Wter Tretment Plnts treted Occoqun Reservoir wter. However, once the Frederick P. Griffith, Jr. (Griffith) Wter Tretment Plnt ws commissioned in My 2006, these older plnts were phsed out nd decommissioned [41]. Upper Occoqun Service Authority The Millrd H. Robbins, Jr. Wter Reclmtion Plnt, operted by the Upper Occoqun Service Authority (UOSA) [formerly known s the Upper Occoqun Sewge Authority], is locted in Centreville, Virgini. UOSA serves the western portions of Firfx nd Prince Willim counties, nd the cities of Mnsss nd Mnsss Prk in the Stte of Virgini. The Millrd H. Robbins Wter Reclmtion Plnt includes primry nd secondry tretment, followed by dvnced wstewter tretment. The dvnced wstewter tretment portion of the plnt includes chemicl clrifiction, two-stge recrbontion with intermedite settling, multimedi filtrtion, grnulr ctivted crbon dsorption, chlorintion for disinfection nd dechlorintion (Figure 5). In 1978, the UOSA Regionl Wter Reclmtion Plnt (lter renmed the Millrd H. Robbins, Jr. Wter Reclmtion Plnt) commenced opertions. Through severl expnsions, the initil B-38

198 MGD cpcity of the Millrd H. Robbins, Jr. Wter Reclmtion Plnt ws incresed to 32 MGD in 1995, followed by nother mjor expnsion to 54 MGD in 2005 [42]. The UOSA plnt is reltively unique in tht the highly treted output from the plnt supplies roughly 20 percent of the inflow into the Occoqun Reservoir, which provides drinking wter used by the FCWA. During drought periods the plnt my briefly provide up to 90 percent of the reservoir inflow. In effect, Firfx Wter is drwing portion of its influent from recycled sewge. UOSA hs demonstrted tht treted plnt effluent is ctully fr clener thn the strem sources of surfce wter inflow into the Occoqun Reservoir [43]. UOSA opertes under Virgini Pollutnt Dischrge Elimintion System Permit, which is issued by the Virgini s Deprtment of Environmentl Qulity. Given the ge of the Millrd H. Robbins, Jr. Wter Reclmtion Plnt, no publicly vilble dt were found regrding the regultory issues ssocited with permitting n indirect surfce wter ugmenttion project in the 1970s. The publicly vilble permit limittions re listed in Tble 15 [44,45]. Source Wter Tble 5 shows the influent wter qulity dt for the Millrd H. Robbins, Jr. Wter Reclmtion Plnt tken between 2006 nd 2010 [46]. The verge (mximum) influent wter qulity dt reveled: 29.4 mg/l mmoni s nitrogen (38.9 mg/l NH 3 -N), 209 mg/l (808 mg/l) TSS, 5 mg/l (8.97 mg/l) totl phosphorous, 5.8 mg/l (7.2 mg/l) foming gents (MBAS), 41.6 mg/l (62.2 mg/l) totl Kjeldhl nitrogen, nd vrious trce metls. The mjority of trce orgnic compounds, including NDMA, were below the MDLs (typiclly less thn 0.01 mg/l), with the exception of chloroform ( chlorinted DBP; mg/l verge [ mg/l mx.]), phenols ( mg/l verge [ mg/l mx.]), nd xylenes ( mg/l verge [ mg/l mx.]). No influent rdiologicl (e.g., gross lph, gross bet, nd urnium) dt were provided. While UOSA did monitor for Clostridium perfringens, fecl nd totl coliforms, nd E. coli, Enterococcus, coliphge, enterovirus, Cryptosporidium, nd Girdi in the influent wter, these dt were presented s log removl dt in the finl product wter (Tble 16) [46]. As such, no directly reportble plnt influent microbiologicl dt were provided. See Finl Product Wter Qulity for further discussion. Primry nd Secondry Tretment Figure 5 provides schemtic drwing of the overll tretment trin for the Millrd H. Robbins, Jr. Wter Reclmtion Plnt [42]. Primry nd secondry tretment includes: Mechniclly clened br screens (0.5-inch openings); 24-ft dimeter vortex grit chmbers; 125-ft dimeter circulr center-feed primry clrifiers with primry scum collection; Archimedes screw primry effluent lift pumps; Aerobic biologicl selectors; 33 B-39

199 Activted sludge ertion bsins; o Most bsins fine-bubble diffusers o All bsins operte in nitrifying mode with ctive D.O. control o Four bsins hve modified Ludzck Ettinger denitrifiction processes; Multistge centrifugl blowers (totl of 5,700 horsepower cpcity [96,200 scfm]); 125-ft dimeter circulr center-feed secondry clrifiers with drft tubes, slot-vlve drft control, nd biofom collection; Continuous monitoring of secondry effluent TSS nd nitrte. Advnced Wter Tretment UOSA uses the high-lime process to reduce phosphorus to below 0.10 mg/l. This process lso serves s brrier to viruses, cptures orgnics leving secondry tretment, nd precipittes hevy metls. Bsic unit processes include [42]: Silos with totl storge for 240 tons of clcium oxide s pebble quicklime; Detention-type lime slkers with lime ging tnks; Rpid mix bsins for lime slurry ddition with feedbck control of ph to 11; Declining-rte floccultion bsins with nionic polymer ddition; 125-ft circulr chemicl clrifiers; First stge recrbontion to lower ph to 10 nd second stge to lower ph to 7. Both stges use corse-bubble diffusers nd introduce crbon dioxide from digester boiler, crbon furnce, nd pelletizer exhust gsses, s well s purchsed CO 2 s necessry; Recrbontion clrifiers between first nd second stges to collect precipitted clcium crbonte; Grvity thickeners to concentrte chemicl nd recrbontion sludge; Recessed chmber plte nd frme filter presses to dewter sludge; nd Onsite 2 million cubic yrd cptive lndfill for dewtered lime solids. The UOSA permit requires TSS below 1 mg/l nd chemicl oxygen demnd below 10 mg/l. To meet these stringent levels, multimedi depth filtrtion nd ctivted crbon re used. UOSA hs two process trins: one with pressure filtrtion nd one with grvity. The grvity system (L/2) is s follows: Six 100-hp verticl turbine pumps trnsfer effluent to filters Alum nd/or polymer s filter id. 10 multimedi filters with 36-in bed of nthrcite, silic, nd grnet Continuous online turbidity mesurement High rte bckwsh with ir scour Intermedite pump sttion with four 120-hp submersible pumps Eight upflow/downflow crbon contctors with 2 million pounds of ctivted crbon, 22-min contct time 34 B-40

200 Trnsfer fcilities nd blow tnks The pressure process trin is similr: 12 horizontl multimedi filters 32 upflow crbon contctors Eight post-filters for crbon fine removl Activted crbon is regenerted onsite with multi-herth furnce Disinfection The finl brrier to pthogens is chlorintion nd dechlorintion process. UOSA uses sodium hypochlorite nd sodium bisulfite, nd is designed to use these chemicls for brekpoint chlorintion s necessry. Storge for 36,000 gllons of sodium hypochlorite; Three primry disinfection chlorintion pumps nd three bckups (52 gph); Three primry brekpoint chlorintion pumps nd three bckups (1086 gph); Two mix chmbers nd four 345,000 gllon covered lbyrinth contct bsins; Continuous online mesurement of totl nd free residul chlorine t mix chmber nd fter 30-minute contct time; Bulk storge of 20,000 gllons of sodium bisulfite nd trnsfer pumps for dy tnks; Three bisulfite feed pumps (52 gph) nd two brekpoint bisulfite feed pumps (250 gph); Continuous online mesurement of pre-dechlorintion totl residul for bisulfite pcing; Continuous online mesurement of post-dechlorintion totl residul; nd Outfll to 180 million gllon finl effluent reservoir Finl Product Wter Qulity UOSA dischrges the finl product wter into Bull Run, which is mjor tributry of the Occoqun Reservoir. Tble 5 provides verge (mximum) finl product wter qulity dt. For the dt shown, the UOSA Millrd H. Robbins, Jr. Wter Reclmtion Plnt ws ble to meet ll regultory permit requirements. Specificlly, the following verge (mximum) wter qulity dt were observed [46]: E. coli < 1.0 per 100 ml Chemicl oxygen demnd = 6 9 mg/l TDS = 472 mg/l (702 mg/l) TOC < 3.1 mg/l (3.5 mg/l) TSS = 0.12 mg/l (0.9 mg/l) Turbidity = 0.16 NTU (0.45 NTU) Totl phosphorous = mg/l (0.14 mg/l) 35 B-41

201 Surfctnts (MBAS) = mg/l (0.038 mg/l) Totl Kjeldhl nitrogen = mg/l Totl nitrogen = 12.4 mg/l (36 mg/l) Ammoni = mg/l (0.53 mg/l) Chlorine residul (during contct time) = mg/l Chlorine residul (finl) = non-detect Finl effluent rdioctive mterils included gross lph emitters 0.12 pci/l (1.1±1.2 pci/l), gross bet emitters pci/l (19.4±2.0 pci/l), rdium 226 nd pci/l (3.16±0.69 pci/l), nd urnium µg/l (0.1±0.00 µg/l). Tble 16 provides microbil removl ssessment cross the Millrd H. Robbins, Jr. Wter Reclmtion Plnt. The lowest log-removl for ny microbe monitored ws for Girdi ( log reduction). Girdi ws detected t 1.1 oocysts/100 ml with detections in three out of fourteen smples. All other microbes (Clostridium perfringens, fecl nd totl coliforms, nd E. coli, Enterococcus, coliphge, enterovirus, nd Cryptosporidium) showed greter thn 4-log reductions (i.e., percent removl) cross the tretment plnt. Figure 5. Tretment Process Flow Digrm for the Millrd H. Robbins, Jr., Wter Reclmtion Fcility. Adpted from [41] Firfx County Wter Authority Firfx County Wter Authority (FCWA) supplies drinking wter to more thn 1.7 million people in Northern Virgini. The primry wter sources re the Potomc River nd the Occoqun Reservoir [41]. This report will only discuss the Occoqun Reservoir wter source. In previous yers, FCWA operted two tretment plnts using Occoqun Reservoir s the source 36 B-42

202 wter: the Lorton nd Occoqun WTPs with nominl combined tretment cpcity of 111 MGD [47]. In My 2006, the 120 MGD Griffith WTP ws brought online to replce the Lorton nd Occoqun WTPs. The Griffith WTP is similr in design to the Lorton nd Occoqun WTPs with the exception of the use of intermedite ozontion nd grnulr ctivted crbon filters (Figure 6). The Griffith WTP ws designed to help FCWA better reduce DBP formtion potentil nd tret tste nd odor episodes [48]. Source Wter Tble 17 provides summry of lnd uses within the Occoqun wtershed [49]. The Occoqun wtershed contins less thn seven percent hevy industry, with more thn 85 percent of the County s households nd nerly ll businesses connected to the public sewer [50]. The most significnt point sources in Firfx County re two lrge wstewter tretment plnts: the Normn M. Cole, Jr. Pollution Control Plnt, which is locted in the southern portion of the County, nd the UOSA Millrd H. Robbins, Jr. Wter Reclmtion Plnt in the Centreville re [43]. Wter qulity from the Millrd H. Robbins, Jr. Wter Reclmtion Plnt ws discussed previously. In norml yers, the UOSA plnt supplies roughly 20 percent of the inflow into the Occoqun Reservoir, while in drought yers, the UOSA plnt my briefly provide up to 90 percent of the reservoir inflow [51]. Tble 5 shows the influent wter qulity dt for the Lorton nd Occoqun WTPs tken in yer 2005 the lst yer tht complete inorgnic nd orgnic wter qulity dt were posted online [52]. Generl verge (mximum) wter qulity dt include: TDS = 147 mg/l (208 mg/l) TOC = 5.1 mg/l (8.6 mg/l) Bromide = 0.02 mg/l (0.03 mg/l) Turbidity = 15 NTU (55 NTU) Totl phosphorous = 0.01 mg/l (0.04 mg/l) Nitrte s N = 1.2 mg/l (2.7 mg/l) Ammoni s N = 0.11 mg/l (0.24 mg/l) It should be noted tht these dt were for single yer nd my not be representtive of longterm wter qulity trends. No occurrence dt for tste-nd-odor compounds or lge were found in publicly vilble records. Tretment Processes Figure 6 shows the bsic tretment processes for the Lorton nd Occoqun WTPs, s well s the new Griffith WTP [47]. It should be noted tht Figure 6 ws developed while the Griffith WTP ws under construction. In 2006, the Griffith WTP replced both the Lorton nd Occoqun WTPs. For the Lorton WTP, the originl (old) nd expnded (new) WTP module designs re shown seprtely. The Griffith WTP is similr in design to the Lorton nd Occoqun WTPs with 37 B-43

203 the exception of the use of intermedite ozontion nd grnulr ctivted crbon filters. Ech WTP used vrition of conventionl tretment, whereby lum nd cogulnt id re dded prior to floccultion, settling, nd filtrtion. Lime or sodium hydroxide (NOH) ws dded for ph djustment. Reservoir wter my lso be treted with powdered ctivted crbon nd/or potssium permngnte (KMnO 4 ) for tste nd odor control, s well s for the removl of trihlomethne precursor compounds. Fluoride ws dded prior to filtrtion. After finl ph djustment, the wter ws chlorminted nd orthophosphte corrosion inhibitor is dded before distribution [47]. Doses for individul chemicls were not provided. Bsic design criteri for individul unit processes cn be found in Figure 6. Finished Wter Qulity The primry purpose for replcing the Lorton nd Occoqun WTPs with the upgrded Griffith WTP ws to lower DBPs in the treted wter nd provide greter protection ginst tste-ndodor episodes in the Occoqun Reservoir [48]. Towrds this end, this report compres the wter qulity dt from the Lorton WTP tken in 2005 (the lst full yer the plnt ws in opertion) nd the wter qulity dt from the Griffith WTP tken in 2010 (Tble 18) [52]. It should be noted tht the Lorton WTP used conventionl tretment (i.e., rpid mix, floccultion, sedimenttion, filtrtion), wheres the Griffith WTP uses intermedite ozontion between the sedimenttion nd filtrtion steps (Figure 6). Additionlly, the Lorton WTP used nthrcite/snd filter medi, wheres the Griffith WTP uses grnulr ctivted crbon filter medi. From Tble 18, DBP dt for HAAs nd THMs from the Griffin WTP effluent were 72 percent nd 33 percent lower thn those for the Lorton WTP. The lower HAA nd THM levels cn be ttributed to the lower usge of chlorine during the tretment process (verge free nd totl chlorine residuls were 1.6 mg/l nd 4.1 mg/l, respectively, for the Lorton WTP, nd 0.9 mg/l nd 3.1 mg/l, respectively, for the Griffith WTP). Though it should be noted tht TOC levels in 2005 were slightly higher t the Lorton WTP thn those reported in 2010 for the Griffith WTP (verge = 5.1 mg/l nd 4.6 mg/l, respectively). Higher TOC levels generlly produce higher HAA nd THM levels when exposed to free nd totl chlorine. No ultrviolet light bsorbnce dt were reported. TOC removl cross the Lorton nd Griffith WTPs were comprble t 53 nd 48 percent, respectively. Therefore, no conclusion could be mde regrding whether the Griffith WTP using ozone nd GAC filters provided better TOC removl thn the Lorton WTP using chlorine nd nthrcite/snd filters. However, the use of ozone t the Griffin WTP did result in the formtion of low levels of bromte (verge < 5 µg/l nd mximum = 6 µg/l). Bromte formtion ws low due to the low levels of bromide in the source wter (mximum 0.04 mg/l). It should lso be noted tht these dt re for single yer per WTP, nd my not represent long term trends. Tble 18 lso provides two indictors of improved tste-nd-odor removl from the Occoqun Reservoir source wter: tste nd threshold odor number (TON). Tste, presumbly derived 38 B-44

204 through flvor profile nlysis though not indicted in the source mteril, improved from n verge (mximum) of 3 (4) for the Lorton WTP to 2 (4) for the Griffith WTP. TON vlues were lso lower for the Griffith WTP [verge (mximum) = 5 (11) for Lorton WTP nd 4 (8) for Griffith WTP]. It should lso be noted tht plnt effluent turbidity improved from n verge (mximum) of 0.56 NTU (3.1 NTU) for the Lorton WTP to 0.08 NTU (0.15 NTU) for the Griffith WTP. The dt presented in Tble 18 indicte tht the overll objectives of lowering DBPs nd improving tste-nd-odor control were chieved by the new Griffith WTP through the use of ozone nd grnulr ctivted crbon filters. 39 B-45

205 FCWA New Lorton Wter Tretment Plnt FCWA Occoqun Wter Tretment Plnt KMnO4 Crbon Source Wter from Occoqun Reservoir KMnO4 Crbon Source Wter from Occoqun Reservoir Cogulnt Cogulnt Aid Lime Rpid Mix (1 Verticl Turbine Mixer) Cogulnt Cogulnt Aid Lime Sttic or Rpid Mix (1 In-line Mechnicl Mixer) Floccultion (4 Bsins, Pddle Floccultors, t 32 MGD Retention Time = 22.5 minutes) Floccultion (5 Upflow Sludge Blnket Tretment Units, Hydrotreter Arm System, t 40 MGD Retention Time = 1.3 minutes) Settled Wter Solids Filter Wsh Wter Cl2 Fluoride Lime Filter Aid Cl2 NH3 Lime Sedimenttion Filtrtion 4 Dul Medi Filters Filter Rte 4.0 gpm/sf Finished Reservoir Wter (4 Dul Lyer Bsins, 1.77 gpm/sf, t 32 MGD Retention Time = 120 minutes) (Anthrcite 12 inches Filter Snd 12 inches Torpedo Snd 6 inches Grded Grvel 12 inches Leopold Underdrin Bckwsh on Hedloss, Turbidity nd Hours in Service) Cpcity = 3.25 million gllons Shred with Old Lorton WTP) Settled Wter Solids Filter Wsh Wter dischrges to Occoqun Reservoir by permit Filter Wsh Wter Cl2 Fluoride Cl2 NH3 Lime Sedimenttion Filtrtion 5 Upflow Sludge Blnket Tretment Units Filters Filter Rte 4.0 gpm/sf Finished Reservoir Wter (5 Upflow Sludge Blnket Tretment Units, 1.46 gpm/sf, t 40 MGD Retention Time = 89.4 minutes) (Anthrcite 12 inches Filter Snd 12 inches Torpedo Snd 6 inches Grded Grvel 12 inches Wheeler Underdrin Bckwsh on Hedloss, Turbidity nd Hours in Service) Cpcity = 1.7 million gllons) Settling Pond Settling Pond Superntnt dischrges to Occqun River by permit Distribution System Superntnt dischrges to Occqun River by permit Distribution System B-46 FCWA Old Lorton Wter Tretment Plnt KMnO4 Crbon Source Wter from Occoqun Reservoir FCWA Griffith Wter Tretment Plnt (under construction) KMnO4 Crbon Source Wter from Occoqun Reservoir Cogulnt Cogulnt Aid Lime Sttic Mix through inlet pipe Cogulnt Cogulnt Aid Lime Rpid Mix (1 Primry Pump Diffusion System 2 Secondry Pump Diffusion Systems) Floccultion (12 Horizontl Slow Tretment Units t 40 MGD Retention Time = 20.4 minutes) Floccultion (4 Bsins, Verticl Hydrofoil Floccultors, t 126 MGD Retention Time = 33 minutes) Settled Wter Solids Sedimenttion (12 Horizontl Slow Tretment Units, 0.37 gpm/sf, t 40 MGD Retention Time = 195 minutes) Settled Wter Solids Sedimenttion (4 Dul Lyer Bsins, gpm/sf, t 126 MGD Retention Time = 33 minutes) Filter Wsh Wter Cl2 Fluoride Cl2 NH3 Lime Filtrtion 12 Horizontl Slow Tretment Units Filter Rte 3.0 gpm/sf Finished Reservoir Wter (Anthrcite 12 inches Filter Snd 12 inches Torpedo Snd 6 inches Grded Grvel 12 inches Wheeler Underdrin Bckwsh on Hedloss, Turbidity nd Hours in Service) Cpcity = 3.25 million gllons Shred with New Lorton WTP) Filter Wsh Wter Cl2 Fluoride Ozone Lime Filter Aid Cl2 NH3 NOH Filtrtion 14 GAC Filters Filter Rte 6.3 gpm/sf Finished Reservoir Wter (Grnulr Activted Crbon 72 inches Filter Snd 12 inches Bckwsh Air Scour on Hedloss, Turbidity nd Hours in Service) Cpcity = 12 million gllons) Settling Pond Settling Pond Superntnt dischrges to Occqun River by permit Distribution System Superntnt dischrges to Occqun River by permit Distribution System Figure 6. Firfx County Wter Authority Wter Tretment Plnt Process Flow Digrms [47] 40

206 Tble 1. Full-Scle Indirect Potble Reuse Projects in Cliforni Project Montebello Foreby Groundwter Rechrge Project Wter Fctory 21 (decommissioned in 2004) West Cost Bsin Brrier Project Ely Bsin Project Almitos Brrier Project Hrbor Wter Recycling Project Dominguez Gp Project Chino Bsin Groundwter Rechrge Project Groundwter Replenishment System Groundwter Rechrge Enhncement nd Tretment (GREAT) Progrm Adpted from [1] Agency Wter Replenishment District of Southern Cliforni Ornge County Wter District West Bsin Municipl Wter District nd Los Angeles County Deprtment of Public Works Inlnd Empire Utilities District (now prt of the Chino Bsin Groundwter Rechrge Project) Los Angeles County Deprtment of Public Works, Wter Replenishment District of Southern Cliforni, nd City of Long Bech City of Los Angeles Inlnd Empire Utilities Agency Ornge County Wter District City of Oxnrd Type of Indirect Potble Reuse Groundwter rechrge vi surfce spreding bsins Sewter brrier vi direct injection Sewter brrier vi direct injection Groundwter rechrge vi surfce spreding bsins Sewter brrier vi direct injection Sewter brrier vi direct injection Groundwter rechrge vi surfce spreding bsins Groundwter rechrge vi direct injection nd surfce spreding bsins Groundwter rechrge vi direct injection nd surfce spreding bsins Strt-Up Dte B-47

207 Tble 2. Drft Cliforni Regultions for Groundwter Rechrge into Potble Aquifers Recycled Wter Qulity Limits Tretment Required Other Selected Requirements Drinking wter MCLs 5 log virus inctivtion 2.2 totl E. coli/100 ml 2 nephelometric turbidity units (NTU) 0.5 mg/l TOC of wstewter origin Action levels for led nd copper Nitrogen limits vry: depend on method used Spreding Secondry Filtrtion Disinfection Soil quifer tretment Injection Secondry Filtrtion Reverse osmosis Advnced oxidtion process (AOP)* Industril pretretment nd source control progrm 80% dilution for spreding (to strt); 50% dilution for spreding pplictions (to strt) tht provide reverse osmosis nd AOP)* 50% dilution for injection (to strt) 6-month retention time underground Monitor recycled wter nd monitoring wells for priority toxic pollutnts, chemicls with stte notifiction levels specified by CDPH, nd unregulted constituents specified by CDPH Opertions pln Contingency pln * AOP must reduce N-nitrosodimethylmine (NDMA) nd 1,4-dioxne by t lest 1.2 logs nd 0.5 logs, respectively. Adpted from [1] Tble 3. Comprison of Methods to Determine Retention Time to Drinking Wter Wells Method Generl Accurcy Level of Effort Retention Time (months) Sfety Fctor Inert Trcer Best Trck dded trcer Intrinsic Trcer Good Smpling of existing indictors 3-D Model Fir Extensive informtion on quifer 12 2 Poor 24 4 Formul (Drcy s Eq.) Adpted from [8] Miniml informtion on quifer 42 B-48

208 Tble 4. Generl Process Trins for Three Cliforni Cse Studies nd Western Austrli Utilizing Membrne Tretment Plnt OCWD GWRS West Cost Bsin Brrier Project WRD Leo Vnder Lns Western Austrli Scle Full Full Full Full / Pilot Source Wter Secondry Effluent Secondry Effluent Tertiry Effluent Secondry Effluent Pretretment Pre-MF Chemicls Oxidnt NOCl NOCl NOCl NOCl Other Ammoni Tretment Microfiltrtion Microfiltrtion Microfiltrtion Microfiltrtion Nominl Pore Size 0.2 µm 0.2 µm 0.1 µm 0.2 µm Membrne Mteril Polypropylene Polypropylene Polyvinylidene Fluoride (PVDF) Polypropylene PVDF Model & Mnufcturer CS, Siemens CMF-S, Siemens USV-6203, Pll Corp. CMF-S, Siemens Post-MF Chemicls ph Adjustment H 2 SO 4 H 2 SO 4 H 2 SO 4 H 2 SO 4 Ammoni Antisclnt Yes Yes Yes Yes Dechlorintion * NHSO 3 -- RO Crtridge filtrtion 5 micron 5 micron 5 micron 5 micron Membrne Type BWRO BWRO BWRO BWRO Model # nd Mnufcturer ESPA2, Hydrnutics ESPA2, Hydrnutics ESPA2, Hydrnutics BW30-FR, Dow ESPA2, Hydrnutics UV Oxidtion Model # nd UVPhox TM, UVPhox TM, UVPhox TM, -- Mnufcturer Trojn Technol. Trojn Technol. Trojn Technol. UV Dose > 400 mj/cm 2 > 115 mj/cm 2 ~149 mj/cm 2 -- H 2 O 2 Dose 3 mg/l 3 mg/l Post-Tretment Decrbontion Prtil Yes Yes -- Disinfectnt -- NOCl -- NOCl Alklinity Lime Lime ph Adjustment NOH NOH Inhibitors * Discontinued in 2008 Kwinn WWTP Beenyup pilot plnt 43 B-49

209 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) Color (15 2nd ) p.c.u < 3 < 3 < 3 Odor (3 2nd ) T.O.N Totl Suspended Solids mg/l Turbidity (5 2nd ) NTU Bicrbonte NS mg/l s CCO Crbonte NS mg/l s CCO Totl Alklinity NS mg/l s CCO Clcium NS mg/l < Cynide 0.2 (0.15) mg/l < < < < 1 DNQ (< 0.002) < 0.1 Tble 5. Wter Qulity Dt for Five Cse Studies Constituent Inorgnic Smpling (Generl Physicl) CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Inorgnic Smpling (Generl Minerl) B-50 Bromide mg/l < 0.01 Chloride (250 2nd ) mg/l Fluoride 2 (1) mg/l < < Foming Agents (MBAS) (0.5 2nd ) mg/l < < Mgnesium NS mg/l Ammoni s N NS mg/l Nitrte s NO 3 45 mg/l Nitrte s N 10 mg/l DNQ (est ) DNQ (est. 0.17) Nitrite s N 1 mg/l < Totl Nitrte + Nitrite s N 10 mg/l Totl Nitrogen mg/l Perchlorte (0.006) mg/l < < < < ph NS Totl Phosphorus mg/l < Potssium mg/l < 1 2 Sodium NS mg/l Sulfte (250 2nd ) mg/l Electricl Conductivity (900 2nd ) µmho/cm TDS (500 2nd ) mg/l Totl Hrdness NS mg/l s CCO < 3 Totl Orgnic Crbon NS mg/l Asbestos 7 MFL 0.2 x 10 6 fibers/l > 10 µm < 0.2 < 0.2 < 0.2 Ultr Violet 254 nm NS bs/cm < Inorgnic Smpling (Trce Metls) Aluminum 1 (0.2 2nd ) (0.6) Antimony (0.02) mg/l < mg/l < DNQ (est ) < Arsenic 0.01 mg/l < DNQ (est ) <

210 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) B-51 Constituent CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Brium 1 mg/l < < Beryllium mg/l < < < < < < Boron (1) mg/l Cdmium ( ) mg/l < < < DNQ (est ) < < DNQ (< ) < Chromium (Totl) 0.05 mg/l < DNQ (est ) DNQ (est ) < DNQ (< ) < Hexvlent Chromium (PHG drft ) mg/l < < < DNQ (< ) Copper 1.3 (1.0 2nd ) (0.3) mg/l < < Iron (0.3 2nd ) mg/l < < 0.02 Led (0.0002) Mngnese (0.05 2nd ) (0.5) Mercury (0.0012) Nickel 0.1 (0.012) mg/l < < < DNQ (est ) < mg/l < < mg/l < < DNQ (est ) 45 < < mg/l < DNQ (est ) DNQ (est ) < Selenium 0.05 mg/l < DNQ (est ) DNQ (est ) < < DNQ (< ) < Silver (0.1 2nd ) mg/l < < < < DNQ (< ) < Thllium (0.0001) mg/l < < < DNQ (est ) < < Vndium (0.05) mg/l < < < Zinc (5 2nd ) mg/l < < Rdiologicl Gross Alph 15 pci/l (gross α-urnium) Gross Bet 4 millirems/yr (50 pci/l) Rdium (0.05) Rdium (0.019) Combined Rdium 226 & pci/l < Rdon NS pci/l Strontium-90 8 (0.35) pci/l < < 3 pci/l < < 3 pci/l < < 1 pci/l < < 1 pci/l < 1.74 < < 8 Tritium 20,000 pci/l < 381 < 210 Urnium 20 (0.43) Microbiology Heterotrophic Plte Counts TT CFU/100 ml pci/l < < 0.7 Totl Coliforms 5%*** MPN/100 ml 1,488,439 16,000,000 < 2 < < 2 < 2.0 Fecl Coliforms t MPN/100 ml 519,671 16,000,000 < 2 E. coli t CFU/100 ml Enterococcus MPN/100 ml

211 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) B-52 Constituent CDPH MCL, PHG or NL Units Cryptosporidium TT oocysts/l Girdi TT cysts/l Enteric Viruses (Totl Culturble Virus) TT MPN IU/100 L Voltile Orgnic Compounds Benzene (0.0005) Bromobenzene Unreg.A mg/l < Bromochloromethne Unreg.B mg/l < Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. mg/l < < < < < Bromodichloromethne (drft ) mg/l < DNQ (est ) DNQ (est ) Bromoform (drft 0.005) mg/l < DNQ (est ) < < Bromomethne Unreg.A mg/l < < < sec-butylbenzene (0.26) mg/l < < < n-butylbenzene (0.26) mg/l < < < tert-butylbenzene (0.26) mg/l < < < Crbon Tetrchloride (0.0001) mg/l < < < < < Chlorobenzene 0.07 mg/l < < < < < Chlorodibromomethne (drft ) mg/l Chloroethne Unreg.A mg/l < < < < Chloroform (drft 0.005) mg/l < < Chloromethne Unreg.A mg/l < < DNQ (est ) 2-Chlorotoluene or o-chlorotoluene Unreg.A (0.14) mg/l < < Chlorotoluene or p-chlorotoluene (0.14) mg/l < < Dibromomethne Unreg.A mg/l < ,2-Dichlorobenzene 0.6 (0.6) mg/l < DNQ (est ) DNQ (est ) < < ,3-Dichlorobenzene Unreg.A mg/l < < < ,4-Dichlorobenzene (0.006) 1,2-Dichloroethne (0.0004) mg/l < < < < mg/l < < < < < ,1-Dichloroethne mg/l < < < < < ,1-Dichloroethene (0.01) cis-1,2-dichloroethene (0.1) trns-1,2-dichloroethene 0.01 (0.06) mg/l < < < < mg/l < < < mg/l < < < < Dichlorodifluoromethne (Freon12) (1) mg/l < < < ,2-Dichloropropne (0.0005) mg/l < < < < < ,3-Dichloropropne Unreg.A mg/l < < ,2-Dichloropropne Unreg.A mg/l < ,1-Dichloropropene Unreg.A mg/l <

212 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) B-53 Constituent 1,3-Dichloropropene (0.0002) CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. mg/l < < cis-1,3-dichloropropene mg/l < < < trns-1,3-dichloropropene mg/l < < < ETBE (Ethyl tertiry butyl ether) Unreg B mg/l < < Ethylbenzene 0.7 (0.3) mg/l < < < < < Hexchlorobutdiene Unreg.B mg/l < < < < Isopropylbenzene (0.77) mg/l < < < p-isopropyltoluene Unreg.B mg/l Methylene Chloride (dichloromethne) (0.004) mg/l < DNQ (est ) < DNQ (< ) < MTBE mg/l < < < < Monochlorobenzene ( nd ) (0.013) mg/l < Nphthlene (0.17) mg/l < < < < < n-propylbenzene Unreg.B (0.26) Styrene 0.1 (0.0005) mg/l < < mg/l < < < TAME (Tertiry myl methyl ether) mg/l < < ,1,1,2-Tetrchloroethne Unreg.A mg/l < < ,1,2,2-Tetrchloroethne (0.0001) Tetrchloroethene ( ) Toluene 0.15 (0.15) mg/l < < < < mg/l < < < mg/l < DNQ (est ) DNQ (est ) < < < ,2,3-Trichlorobenzene Unreg.B mg/l < < ,2,4-Trichlorobenzene 0.07 (0.005) 1,1,1-Trichloroethne 0.2 (1) 1,1,2-Trichloroethne (0.0003) Trichloroethene (0.0008) Trichlorofluoromethne 0.15 (0.7) 1,2,3-Trichloropropne Unreg.A ( ) 1,1,2-Trichloro-1,2,2-trifluoroethne (FREON) 1.2 (4) mg/l < < < < mg/l < < < < mg/l < < < < < mg/l < < < mg/l < < < mg/l < < < DNQ (< ) mg/l < < ,3,5-Trimethylbenzene (0.33) mg/l < < ,2,4-Trimethylbenzene (0.33) mg/l < < Vinyl Chloride ( ) mg/l < < < < <

213 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) B-54 Constituent Xylenes (single or sum of isomers) 1.75 (1.8) CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. mg/l < < < Totl THMs mg/l Semivoltile Orgnic Compounds Benzo (A) Pyrene ( ) Di (2-Ethylhexyl) Adipte 0.4 (0.2) Di (2-Ethylhexyl) Phthlte (0.012) Fumignts mg/l < < < < < mg/l < mg/l DNQ (est ) DNQ (est ) < < Ethylene dibromide (EDB) mg/l < < Dibromochloropropne (DBCP) ( ) Orgnochlorine Pesticides Alchlor (0.004) Aldrin Unreg. C ( ) Chlordne ( ) Chlorothnlonil Unreg. B mg/l < Dieldrin Unreg. C ( ) Endrin (0.0018) Heptchlor ( ) Heptchlor Epoxide ( ) Hexchlorobenzene ( ) Hexchlorocyclopentdiene 0.05 (0.05) Lindne ( ) Methoxychlor 0.03 (0.03) Polychlorinted Biphenyls ( ) mg/l < < mg/l < < < mg/l < < < < < mg/l < < < < mg/l < < < < < mg/l < < < < < mg/l < < < < < mg/l < < < < < mg/l < < < < < mg/l < < < < < mg/l < < mg/l < < < mg/l < Aroclor-1016 (PCB-1016) mg/l < < < < < Aroclor-1221 (PCB-1221) mg/l < < < < < Aroclor-1232 (PCB-1232) mg/l < < < < < Aroclor-1242 (PCB-1242) mg/l < < < < < Aroclor-1248 (PCB-1248) mg/l < < < < < Aroclor-1254 (PCB-1254) mg/l < < < < < Aroclor-1260 (PCB-1260) mg/l < < < < <

214 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) B-55 Constituent CDPH MCL, PHG or NL Units Propchlor (0.09) mg/l < Toxphene ( ) Orgnochlorine Herbicides Bentzon (Bsgrn) (0.2) 2,4-Dichlorophenoxycetic cid (2,4-D) 0.02 (0.07) Dlpon 0.2 (0.79) Dicmb Unreg.C mg/l < Dinoseb (0.014) Pentchlorophenol (0.0003) Pichlorm 0.5 (0.5) Silvex (2,4,5-TP) 0.05 (0.025) Crbmte Pesticides Diuron Unreg.B mg/l < Aldicrb Unreg.C (0.007) Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. mg/l < < < < < mg/l < < < mg/l < < < mg/l < < < mg/l < < < mg/l < < < < < mg/l < < < mg/l < < < mg/l < Aldicrb sulfone Unreg.C mg/l < Aldicrb sulfoxide Unreg.C mg/l < Bygon (Propoxur) (0.03) mg/l < Crbofurn (0.0017) Crbryl Unreg.C (0.7) mg/l < < < mg/l < hydroxycrbofurn Unreg.C mg/l < Methomyl Unreg.C mg/l < Oxmyl 0.05 (0.026) Miscellneous Diqut 0.02 (0.015) Endothll 0.1 (0.58) Glyphoste 0.7 (0.9) Prqut mg/l < Polynucler Aromtic hydrocrbon mg/l Anthrcene mg/l Fluornthene mg/l Phennthrene mg/l Pyrene mg/l mg/l < < < mg/l < < < mg/l < < < mg/l < < <

215 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) B-56 Constituent CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. 2,3,7,8-TCDD Dioxin 3 x 10-8 (1 x 10-9 ) mg/l < 5 x 10-9 < 6 x < 1.10 x 10-8 < 5 x 10-9 Nitrogen/Phosphorus Pesticides Atrzine ( ) Bromcil Unreg.B mg/l < Butchlor Unreg.C mg/l < mg/l < < < Dizinon (0.006) mg/l < < < Dimethote Unreg.B (0.001) mg/l < Mlthion (0.16) mg/l < Metolchlor Unreg.C mg/l < Metribuzin Unreg.C mg/l < Molinte 0.02 (0.001) mg/l < < < Prometryn Unreg.B mg/l < Simzine (0.004) Thiobencrb (Bolero) 0.07 ( nd ) (0.07) Other Chemicls mg/l < < < mg/l < < < Benzene Hexchloride (-BHC) ( ) mg/l < < < b-benzene Hexchloride (b-bhc) ( ) mg/l < < ,4-Dimethylphenol (0.1) mg/l < < < ,4-Dioxne (0.003) mg/l < < < Diphenmide (0.2) mg/l < Ethion (0.004) mg/l < Formldehyde (0.1) mg/l < Isopropyl N (3-Chlorophenyl) Crbmte (CIPC) (1.2) mg/l Methyl Isobutyl Ketone (MIBK) (0.12) mg/l < < < Methyl Prthion (0.002) mg/l N-Nitrosodimethylmine (NDMA) ( ) mg/l < Prthion (0.040) mg/l < Pentchloronitrobenzene (0.02) mg/l Phenol (4.2) mg/l < < < < DNQ (< ) < Trithion (0.007) mg/l < Cptn (0.015) mg/l < Chloropicrin (0.037) mg/l < Tert butyl lcohol (0.012) mg/l < < < Crbon disulfide mg/l < < Chlorte mg/l < Ethylene glycol mg/l < 32 HMX mg/l N-Nitrosodiethymine (NDEA) mg/l < <

216 OCWD GWRS (Feb 2008 Apr 2010) WBMWD Brrier System LACSD Leo Vnder Lns (2009) B-57 Constituent CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent (2009) Effluent ( ) Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. N-Nitrosodi-n-propylmine (NDPA) mg/l < < < n-propylbenzene mg/l RDX mg/l 2,4,6-Trinitrotoluene (TNT) mg/l Endocrine Disrupting Compounds Ethinyl estrdiol mg/l < < α Ethinyl estrdiol mg/l 17-β Estrdiol mg/l < Estrone mg/l < < Bisphenol A mg/l < Nonylphenol (4-Nonyl phenol) mg/l < Phrmceuticls nd Other Chemicls Acetminophen mg/l < < < Cffeine < < < Crbomzpine < < Gemfibrozil mg/l < Ibuprofen mg/l < < < Triclosn mg/l < < Dizepm Nproxen Clofibric cid ND Not Detected (#) Number in prenthesis is Cliforni Public Helth Gol (#) Number in prenthesis nd bold itlics is Cliforni Notifiction Level or rchived Action Level (# 2nd ) Indictes vlue is Cliforni secondry MCL NS No Stndrd. Monitoring required in Cliforni * Ave CRW microbiologicl dt from 1/2005-6/2009 *** No more thn 5% of the smples/month my be positive t If repet totl coliform smple is fecl-coliform or E. coli-positive, the system is in violtion of the MCL for totl coliforms TT Tretment technique in plce of MCL Unreg.A Unregulted. Monitoring required for ll community nd non- trnsient, non-community wter systems Unreg.B Unregulted. Monitoring required for ll community nd non- trnsient, non-community wter systems if determined vulnerble Unreg.C Unregulted. Monitoring required for ll community nd non- trnsient, non-community wter systems if determined vulnerble Unreg.D Unregulted. Monitoring my be required t Stte's discretion Unreg.E Unregulted. Monitoring required unless determined not vulnerble. DNQ Detected, but Not Quntifible. Estimted concentrtion vlue in prenthesis 1 Beenyup only 2 Kwinn only 3 Mnipulted dt - x ve = (x 1n 1+x 2n 2)/(n 1+n 2), where x i is the men vlue for ech plnt nd n i is the number of smples tken to determine tht men vlue **** Mnipulted dt - x ve = [(x1n1+x2n2)/(n1+n2)]*2.7*10-11 *10 12, where x i = men vlue for ech plnt, n i = number of smples tken to determine tht men vlue, 2.7*10-11 = number of Ci in 1 Bq, = number of pci in 1 Ci 2006 to 2010 b 2010 c 2007 to 2010 d September 2002 e 2008 to 2010 f 2009 & 2010 g As totl Kjeldhl nitrogen 51

217 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority Lorton/Occoqun Wter Tretment Plnts Color (15 2nd ) p.c.u < 1 1 < Odor (3 2nd ) T.O.N. < Totl Suspended Solids mg/l b 808 b 0.12 b 0.9 b 9 35 Turbidity (5 2nd ) NTU b 0.45 b Constituent Inorgnic Smpling (Generl Physicl) CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Inorgnic Smpling (Generl Minerl) B-58 Bicrbonte NS mg/l s CCO Crbonte NS mg/l s CCO Totl Alklinity NS mg/l s CCO b 122 b Clcium NS mg/l b 54.2 b 74.9 b 79.1 b Cynide 0.2 (0.15) mg/l < < < 0.01 c < 0.01 c Bromide mg/l < b 0.12 b b b Chloride (250 2nd ) mg/l b 102 b 88.2 b 93.1 b Fluoride 2 (1) mg/l < Foming Agents (MBAS) (0.5 2nd ) mg/l 5.8 b 7.2 b b b Mgnesium NS mg/l < b 10.4 b 5.5 b 6 b Ammoni s N NS mg/l b 38.9 b b 0.53 b Nitrte s NO3 45 mg/l Nitrte s N 10 mg/l b 25.3 b Nitrite s N 1 mg/l b b Totl Nitrte + Nitrite s N 10 mg/l b 25.3 b Totl Nitrogen mg/l 41.6 bg 62.2 bg 12.4 b 36 b Perchlorte (0.006) mg/l ph NS b 7.9 b 7.4 b 7.8 b Totl Phosphorus mg/l b 8.97 b b 0.14 b Potssium mg/l Sodium NS mg/l b 77.9 b 75.9 b 77.7 b Sulfte (250 2nd ) mg/l b 106 b 87.5 b 108 b Electricl Conductivity (900 2nd ) µmho/cm b 917 b 713 b 928 b TDS (500 2nd ) mg/l < b 545 b 472 b 702 b Totl Hrdness NS mg/l s CCO b 194 b Totl Orgnic Crbon NS mg/l b 3.5 b Asbestos 7 MFL 0.2 x 10 6 fibers/l > 10 µm Ultr Violet 254 nm NS bs/cm d d Inorgnic Smpling (Trce Metls) Aluminum 1 (0.2 2nd ) (0.6) Antimony (0.02) mg/l < e mg/l < < b < b < Arsenic 0.01 mg/l < < b b b b <

218 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority Lorton/Occoqun Wter Tretment Plnts B-59 Constituent CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Brium 1 mg/l < b b < b Beryllium mg/l < < < b < b < Boron (1) mg/l Cdmium ( ) mg/l < < b b < b < Chromium (Totl) 0.05 mg/l b b < b < Hexvlent Chromium (PHG drft ) mg/l < 0.05 < 0.05 < b Copper 1.3 (1.0 2nd ) (0.3) mg/l b b b b Iron (0.3 2nd ) mg/l < < 0.02 e Led (0.0002) Mngnese (0.05 2nd ) (0.5) Mercury (0.0012) Nickel 0.1 (0.012) mg/l < b b < b mg/l < < e mg/l < < < b < b < mg/l b b b b < Selenium 0.05 mg/l < < b b < b < Silver (0.1 2nd ) mg/l < < b b < b < Thllium (0.0001) Vndium (0.05) mg/l < < mg/l < < < b < b < Zinc (5 2nd ) mg/l b b b b < Rdiologicl Gross Alph 15 pci/l (gross α-urnium) Gross Bet 4 millirems/yr (50 pci/l) Rdium (0.05) Rdium (0.019) pci/l ± 1.2 pci/l ± 2.0 pci/l ± 0.34 pci/l ± 0.6 Combined Rdium 226 & pci/l ± 0.69 Rdon NS pci/l Strontium-90 8 (0.35) Tritium 20,000 pci/l Urnium 20 (0.43) Microbiology pci/l pci/l ± 0.00 Heterotrophic Plte Counts TT CFU/100 ml Totl Coliforms 5%*** MPN/100 ml 0.85 b b Fecl Coliforms t MPN/100 ml ND ND E. coli t CFU/100 ml < 1.0 b 53

219 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority Lorton/Occoqun Wter Tretment Plnts B-60 Constituent CDPH MCL, PHG or NL Units Enterococcus MPN/100 ml Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Cryptosporidium TT oocysts/l < Girdi TT cysts/l Enteric Viruses (Totl Culturble Virus) TT MPN IU/100 L Voltile Orgnic Compounds Benzene (0.0005) mg/l < 0.01 c < < Bromobenzene Unreg.A mg/l < < < Bromochloromethne Unreg.B mg/l < Bromodichloromethne (drft ) mg/l < 0.01 c < Bromoform (drft 0.005) mg/l < 0.01 c < < Bromomethne Unreg.A mg/l < < < 0.01 c < 0.01 c < sec-butylbenzene (0.26) mg/l < < < n-butylbenzene (0.26) mg/l < tert-butylbenzene (0.26) mg/l < Crbon Tetrchloride (0.0001) mg/l < < < 0.01 c < < Chlorobenzene 0.07 mg/l < < Chlorodibromomethne (drft ) mg/l < < 0.01 c < 0.01 c < Chloroethne Unreg.A mg/l < < < 0.01 c < 0.01 c < Chloroform (drft 0.005) mg/l c c < Chloromethne Unreg.A mg/l < 0.01 c < 0.01 c < Chlorotoluene or o-chlorotoluene Unreg.A (0.14) mg/l < < < Chlorotoluene or p-chlorotoluene (0.14) mg/l < < < Dibromomethne Unreg.A mg/l < ,2-Dichlorobenzene 0.6 (0.6) mg/l < < 0.01 c < < ,3-Dichlorobenzene Unreg.A mg/l < < < 0.01 c < 0.01 c < ,4-Dichlorobenzene (0.006) 1,2-Dichloroethne (0.0004) mg/l < 0.01 c < < mg/l < < < 0.01 c < < ,1-Dichloroethne mg/l < < < 0.01 c < 0.01 c < ,1-Dichloroethene (0.01) cis-1,2-dichloroethene (0.1) trns-1,2-dichloroethene 0.01 (0.06) mg/l < 0.01 c < < mg/l < < 0.01 c < < mg/l < < < < Dichlorodifluoromethne (Freon12) (1) mg/l < < < ,2-Dichloropropne (0.0005) mg/l < 0.01 c < < ,3-Dichloropropne Unreg.A mg/l < < <

220 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority Lorton/Occoqun Wter Tretment Plnts B-61 Constituent CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. 2,2-Dichloropropne Unreg.A mg/l < < < ,1-Dichloropropene Unreg.A mg/l < < < ,3-Dichloropropene (0.0002) mg/l < 0.01 c < 0.01 c cis-1,3-dichloropropene mg/l < trns-1,3-dichloropropene mg/l < ETBE (Ethyl tertiry butyl ether) Unreg B mg/l Ethylbenzene 0.7 (0.3) mg/l < < 0.01 c < < Hexchlorobutdiene Unreg.B mg/l < < < 0.01 c < 0.01 c < Isopropylbenzene (0.77) mg/l < < < p-isopropyltoluene Unreg.B mg/l < Methylene Chloride (dichloromethne) (0.004) mg/l < < < 0.01 c < < MTBE mg/l < < < Monochlorobenzene ( nd ) (0.013) mg/l < 0.01 c < 0.01 c Nphthlene (0.17) mg/l < < 0.01 c < 0.01 c < n-propylbenzene Unreg.B (0.26) Styrene 0.1 (0.0005) TAME (Tertiry myl methyl ether) mg/l mg/l < mg/l < < ,1,1,2-Tetrchloroethne Unreg.A mg/l < < < ,1,2,2-Tetrchloroethne (0.0001) Tetrchloroethene ( ) Toluene 0.15 (0.15) mg/l < < < 0.01 c < 0.01 c < mg/l < < 0.01 c < < mg/l < 0.01 c < < ,2,3-Trichlorobenzene Unreg.B mg/l < < ,2,4-Trichlorobenzene 0.07 (0.005) 1,1,1-Trichloroethne 0.2 (1) 1,1,2-Trichloroethne (0.0003) Trichloroethene (0.0008) Trichlorofluoromethne 0.15 (0.7) 1,2,3-Trichloropropne Unreg.A ( ) 1,1,2-Trichloro-1,2,2-trifluoroethne (FREON) 1.2 (4) mg/l < < < 0.01 c < < mg/l < < < 0.01 c < < mg/l < 0.01 c < < mg/l < < < 0.01 c < < mg/l < mg/l < < < mg/l < < ,3,5-Trimethylbenzene (0.33) mg/l <

221 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority Lorton/Occoqun Wter Tretment Plnts B-62 Constituent CDPH MCL, PHG or NL Units 1,2,4-Trimethylbenzene (0.33) mg/l < < Vinyl Chloride ( ) Xylenes (single or sum of isomers) 1.75 (1.8) Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. mg/l < < < 0.01 c < < mg/l < c c < c < Totl THMs mg/l Semivoltile Orgnic Compounds Benzo (A) Pyrene ( ) Di (2-Ethylhexyl) Adipte 0.4 (0.2) Di (2-Ethylhexyl) Phthlte (0.012) Fumignts mg/l < 0.01 c < < mg/l < < mg/l c c < < Ethylene dibromide (EDB) mg/l < < < < Dibromochloropropne (DBCP) ( ) Orgnochlorine Pesticides Alchlor (0.004) Aldrin Unreg. C ( ) Chlordne ( ) Chlorothnlonil Unreg. B mg/l < < Dieldrin Unreg. C ( ) Endrin (0.0018) Heptchlor ( ) Heptchlor Epoxide ( ) Hexchlorobenzene ( ) Hexchlorocyclopentdiene 0.05 (0.05) Lindne ( ) Methoxychlor 0.03 (0.03) Polychlorinted Biphenyls ( ) mg/l < < mg/l < < < < mg/l < < < < < mg/l < < not detected c < < mg/l < < < < < mg/l < < < c < < mg/l < < < c < < mg/l < < mg/l < < c < < mg/l < N/A N/A N/A < c < < mg/l < < < c < < mg/l < < < < < mg/l Aroclor-1016 (PCB-1016) mg/l not detected c < c < Aroclor-1221 (PCB-1221) mg/l not detected c < c < Aroclor-1232 (PCB-1232) mg/l not detected c < c < Aroclor-1242 (PCB-1242) mg/l not detected c < c <

222 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority Lorton/Occoqun Wter Tretment Plnts B-63 Constituent CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Aroclor-1248 (PCB-1248) mg/l not detected c < < Aroclor-1254 (PCB-1254) mg/l not detected c < < Aroclor-1260 (PCB-1260) mg/l not detected c < < Propchlor (0.09) mg/l < < < Toxphene ( ) Orgnochlorine Herbicides Bentzon (Bsgrn) (0.2) 2,4-Dichlorophenoxycetic cid (2,4-D) 0.02 (0.07) Dlpon 0.2 (0.79) mg/l not detected c < < mg/l < < < mg/l < < < mg/l < < Dicmb Unreg.C mg/l < < < Dinoseb (0.014) Pentchlorophenol (0.0003) Pichlorm 0.5 (0.5) Silvex (2,4,5-TP) 0.05 (0.025) Crbmte Pesticides mg/l < < mg/l < 0.02 c < mg/l ND < mg/l < < Diuron Unreg.B mg/l < 0.01 < 0.01 < f Aldicrb Unreg.C (0.007) mg/l < < < Aldicrb sulfone Unreg.C mg/l < f < Aldicrb sulfoxide Unreg.C mg/l < f < Bygon (Propoxur) (0.03) mg/l < < < f < Crbofurn (0.0017) Crbryl Unreg.C (0.7) mg/l < < < f < mg/l < < < f < hydroxycrbofurn Unreg.C mg/l < f < Methomyl Unreg.C mg/l < < < f < Oxmyl 0.05 (0.026) Miscellneous Diqut 0.02 (0.015) Endothll 0.1 (0.58) Glyphoste 0.7 (0.9) mg/l < f < mg/l < mg/l < < < mg/l < Prqut mg/l ND Polynucler Aromtic hydrocrbon mg/l 57

223 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority Lorton/Occoqun Wter Tretment Plnts B-64 Constituent CDPH MCL, PHG or NL Units Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Anthrcene mg/l < 0.01 c < f < Fluornthene mg/l < 0.01 c < f < Phennthrene mg/l < 0.01 c < f < Pyrene mg/l < 0.01 c < f < ,3,7,8-TCDD Dioxin 3 x 10-8 (1 x 10-9 ) mg/l < < Nitrogen/Phosphorus Pesticides Atrzine ( ) mg/l < < Bromcil Unreg.B mg/l < < < f < Butchlor Unreg.C mg/l < f < Dizinon (0.006) mg/l < < < f < Dimethote Unreg.B (0.001) mg/l < < < f < Mlthion (0.16) mg/l < < < f Metolchlor Unreg.C mg/l < < f Metribuzin Unreg.C mg/l < < < f < Molinte 0.02 (0.001) mg/l < < < f < Prometryn Unreg.B mg/l < f < Simzine (0.004) Thiobencrb (Bolero) 0.07 ( nd ) (0.07) Other Chemicls mg/l < < mg/l < f < Benzene Hexchloride (-BHC) ( ) mg/l < f b-benzene Hexchloride (b-bhc) ( ) mg/l < f 2,4-Dimethylphenol (0.1) mg/l N/A < 0.01 c < 0.01 c 1,4-Dioxne (0.003) mg/l Diphenmide (0.2) mg/l < < Ethion (0.004) mg/l < < < f Formldehyde (0.1) mg/l Isopropyl N (3-Chlorophenyl) Crbmte (CIPC) (1.2) mg/l Methyl Isobutyl Ketone (MIBK) (0.12) mg/l Methyl Prthion (0.002) mg/l < < < f N-Nitrosodimethylmine (NDMA) ( ) mg/l < 0.01 c c f Prthion (0.040) mg/l < f Pentchloronitrobenzene (0.02) mg/l < f Phenol (4.2) mg/l c c < 0.01 c Trithion (0.007) mg/l Cptn (0.015) mg/l < < Chloropicrin (0.037) mg/l Tert butyl lcohol (0.012) mg/l Crbon disulfide mg/l < <

224 Combined Results for Kwinn nd Beenyup Upper Occoqun Service Authority TT Tretment technique in plce of MCL Unreg.A Unregulted. Monitoring required for ll community nd non- trnsient, non-community wter systems Unreg.B Unregulted. Monitoring required for ll community nd non- trnsient, non-community wter systems if determined vulnerble Unreg.C Unregulted. Monitoring required for ll community nd non- trnsient, non-community wter systems if determined vulnerble Unreg.D Unregulted. Monitoring my be required t Stte's discretion Unreg.E Unregulted. Monitoring required unless determined not vulnerble. DNQ Detected, but Not Quntifible. Estimted concentrtion vlue in prenthesis 1 Beenyup only 2 Kwinn only 3 Mnipulted dt - x ve = (x 1n 1+x 2n 2)/(n 1+n 2), where x i is the men vlue for ech plnt nd n i is the number of smples tken to determine tht men vlue **** Mnipulted dt - x ve = [(x1n1+x2n2)/(n1+n2)]*2.7*10-11 *10 12, where x i = men vlue for ech plnt, n i = number of smples tken to determine tht men vlue, 2.7*10-11 = number of Ci in 1 Bq, = number of pci in 1 Ci Lorton/Occoqun Wter Tretment Plnts 2006 to 2010 b 2010 c 2007 to 2010 d September 2002 e 2008 to 2010 f 2009 & 2010 g As totl Kjeldhl nitrogen B-65 Constituent CDPH MCL, PHG or NL Units Chlorte mg/l Ethylene glycol mg/l HMX mg/l Influent Effluent Influent Effluent Influent Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. Ave. Mx. N-Nitrosodiethymine (NDEA) mg/l < c N-Nitrosodi-n-propylmine (NDPA) mg/l < < 0.01 c < c n-propylbenzene mg/l < < RDX mg/l 2,4,6-Trinitrotoluene (TNT) mg/l Endocrine Disrupting Compounds Ethinyl estrdiol mg/l < < α Ethinyl estrdiol mg/l < f 17-β Estrdiol mg/l < < f Estrone mg/l < < f Bisphenol A mg/l < < < < < f Nonylphenol (4-Nonyl phenol) mg/l < f Phrmceuticls nd Other Chemicls Acetminophen mg/l < < f Cffeine < f < Crbomzpine f f Gemfibrozil mg/l < f f Ibuprofen mg/l < < f Triclosn mg/l Dizepm < b Nproxen < f Clofibric cid < f ND Not Detected (#) Number in prenthesis is Cliforni Public Helth Gol (#) Number in prenthesis nd bold itlics is Cliforni Notifiction Level or rchived Action Level (# 2nd ) Indictes vlue is Cliforni secondry MCL NS No Stndrd. Monitoring required in Cliforni * Ave CRW microbiologicl dt from 1/2005-6/2009 *** No more thn 5% of the smples/month my be positive t If repet totl coliform smple is fecl-coliform or E. coli-positive, the system is in violtion of the MCL for totl coliforms 59

225 Tble 6. Non-crcinogenic Risk Assessment 1 for OCWD GWRS Product Wter Constituent Men Concentrtion (µg/l) Dose 2 (mg/kg/dy) Reference Dose (mg/kg/dy) Hzrd Index GWRS Product Wter Metls Arsenic E E E-03 Brium E E E-04 Boron E E E-02 Chromium E E E-05 Coblt E E E-05 Mngnese E E E-04 Selenium E E E-02 Orgnics 1,4-Dichlorobenzene E E E-04 Bromodichloromethne E E E-04 Bromoform E E E-04 Chloroform E E E-03 Dibromocetonitrile E E E-04 Dichlorocetonitrile E E E-04 Dibromochloromethne E E E-04 Methylene Chloride E E E-04 Tetrchloroethene E E E-04 Totl Bsed on constituents detected nd listed on IRIS or OEHHA with reference dose for toxicity 2 Point estimte bsed on 2 L/dy wter intke Adpted from [19] 60 B-66

226 Tble 7. Non-crcinogenic Risk Assessment 1 for Snt An River nd Imported Wters Constituent Men Concentrtion (µg/l) Dose 2 (mg/kg/dy) Reference Dose (mg/kg/dy) Hzrd Index Snt An River Wter Metls Arsenic E E E-01 Brium E E E-02 Boron E E E-02 Mngnese E E E-03 Nickel E E E-02 Thllium E E E-03 Orgnics Bis(2-ethylhexyl) phthlte E E E-03 Bromodichloromethne E E E-04 Bromoform E E E-04 Butylbenzyl phthlte E E E-04 Chloroform E E E-03 Dizinon E E E-02 Di-n-butylphthlte E E E-04 Diuron E E E-02 Formldehyde E E E-04 Methoxychlor E E E-03 Propzine E E E-04 Simzine E E E-03 Totl 0.65 Imported Surfce Wters Metls Arsenic E E E-01 Brium E E E-02 Boron E E E-02 Mngnese E E E-03 Molybdenum E E E-02 Selinium E E E-02 Strontium E E E-02 Orgnics Bis(2-ethylhexyl) phthlte E E E-03 Bromodichloromethne E E E-04 Chloroform E E E-03 Dibromochloromethne E E E-04 Totl Bsed on constituents detected nd listed on IRIS or OEHHA with reference dose for toxicity 2 Point estimte bsed on 2 L/dy wter intke Adpted from [19] 61 B-67

227 Tble 8. Comprison of Crcinogenic Risk for OCWD GWRS nd Snt An River Wter Metls Constituent Men Concentrtion (µg/l) GWRS Product Wter Slope Fctor Risk 1,2 (mg/kg/dy) 1 (prob/lifetime) Arsenic E E-06 Orgnics 1,4-Dichlorobenzene E E-07 Bromodichloromethne E E-08 Bromoform E E-08 Chloroform E E-07 Methylene Chloride E E-07 Tetrchloroethene E E-07 NDMA E E-05 Totl 3.3 E-05 Metls Snt An River Wter Arsenic E E-04 Orgnics Bis(2-ethylhexyl) phthlte E E-07 Bromodichloromethne E E-08 Bromoform E E-08 Chloroform E E-08 NDMA E E-06 Totl 1.9 E-04 1 Bsed on 95% SF, nd men concentrtion 2 Point estimte bsed on 2 L/dy wter intke Adpted from [19] 62 B-68

228 Tble 9. Summry of Trce-Orgnic Compounds Removl cross WBMWD s Brrier Project Contminnt 1,4-Dichlorobenzene (p-dichlorobenzene) Dichlorocetic cid (DCAA) Trichlorocetic cid (TCAA) Appliction Phrm./Personl Cre Product Phrm./Personl Cre Product Phrm/Personl Cre Product Rejection Across MF (%) Rejection Across RO (%) UV Oxidtion (%) Removl Across Post Tretment (decrb/ph dj./cl 2 ) (%) < 5 42 >77 ND ND > 95 ND ND ND > 97 ND ND Bromodichloromethne Trihlomethne < > 72 Bromoform Trihlomethne < 5 > 78 ND ND Chloroform Trihlomethne < > 78 Dibromochloromethne Trihlomethne < 5 63 > 73 ND Estrone Endocrine Disruptor NC NC NC ND Bis (2-ethylhexyl) phthlte Plsticizer CON ND ND ND Butylbenzyl phthlte Plsticizer NC NC NC NC Diethyl phthlte Plsticizer CON NC NC NC Di-n-butyl phthlte Plsticizer CON CON ND NC Dibromomethne Solvent < 5 < 5 27 > 66 Methylene Chloride Solvent < 5 < 5 6 > 68 Methyl-tert-butyl ether Solvent < 5 > 81 ND ND Tetrchloroethene Solvent < 5 69 > 78 ND Toluene Solvent NC > 85 ND ND 1,4 Dioxne Solvent < 5 > 89 ND ND Bromochloromethne Fire Ext. < 5 < 5 10 > 72 PBDE-154 Electronics NC 33 ND ND Dlpon Herbicide < 5 89 ND ND NDMA Ind. By-product Increse* 50 > 97 Increse* * These tretment steps include NOCl ddition which my ccount for the observed increses in NDMA concentrtion CON = Smple contmintion suspected NC = Dt not consistent nd thus rejection rtes were not determined ND = Not determined Adpted from [29] using dt from B-69

229 Tble 10. Wter Qulity Results for Beenyup Pilot Plnt in Western Austrli Prmeter Beenyup Secondry WW Beenyup Pilot Plnt Post-RO Removl by MR/RO Std. Men Dev. n Men Std. Dev. n Averge % Alklinity Suspended Solids Orgnic Nitrogen No Dt TKN Phosphte Totl Phosphorus Clcium Potssium Mgnesium < Silic < Chem. Oxygen Demnd BOD 5 (Ops Dt) < Medin < 5 (12.8) (8.5) (218) Totl Orgnic Crbon Dissolved Orgnic Crbon Oil nd Grese No Dt Colour (TCU) < Conductivity (µs/cm) (Ops dt) b (1292) ph - in situ c (Ops Dt) b (94.4) (16702) (28.2) 5.5 (7.0) 12 (16702) (5.90) (0.50) (16702) Dissolved Oxygen c Chlorine c Chlormine c Opertionl dt used in % removl clcultions * AGWR 2008 Guideline level only b Opertionl dt were recorded every 10 minutes while RO system opertionl: 3/18/08 to 12/23/08 c Mesures tken on site either with probe or Hch chemicl method Adpted from [36] using dt from 2006 to 2008 (97.8) B-70

230 Tble 11. Log Removl/Inctivtion Credits Adopted for Beenyup Advnced Wter Tretment Plnt in Western Austrli Unit Process Bcteri (Cmpylobcter) Virus (Adenovirus) Protozo (Cryptosporidium) Secondry Tretment Ultrfiltrtion Reverse Osmosis UV Disinfection (200 mj/cm 2 ) Totl Adpted from [39]; * Per [38] Required* Tble 12. Surrogtes Used to Guge Opertionl Stbility in Western Austrli Criticl Control Point Feed Wter Acceptnce Criteri Surrogte Dissolved Oxygen Mesured online in rel time with DO meters in WWTP ertion tnks Hzrd for which surrogte represents removl Orgnic chemicls, pthogens, prticultes TOC UV Absorbnce Dissolved orgnic chemicls Turbidity Turbidity meter Prticultes, pthogens, chemicls MF Opertion Turbidity Turbidity meters Prticultes, pthogens Turbidity Prticle counter Prticultes, pthogens Pressure Decy Dily test: Pressure Filure in sels, (Dily) pre nd post membrne membrnes degrdtion RO Opertion Conductivity Conductivity meter Inorgnic chemicls, orgnic chemicls, pthogens Monitoring loctions WWTP ertion tnks Rw (AWTP Feed) Rw (AWTP Feed) Rw, Post-MF Post-MF Pre- nd Post-MF Post-MF, Post-RO TOC TOC Anlyzer Orgnic chemicls Post-MF, Post-RO UV Opertion UV Trnsmittnce UV intensity Microbil pthogens UV Feed Injection Acceptnce Criteri Adpted from [36] UV dose (fluorescence) Oxidtion Reduction Potentil UV dose nd flow Microbil pthogens UV unit ORP meter Chemicl stbility (ffecting quifer risks) ph ph meter Chemicl stbility (ffecting quifer risks) Treted wter Treted wter 65 B-71

231 Tble 13. Suggested Chemicl Indictors to Guge Tretment Performnce in Western Austrli Chemicl Chemicl Indictor Properties Boron Metlloid Smll size Chrged (+ or -) Very hydrophilic Nitrte Inorgnic nion Smll size Very hydrophilic Detection in Secondry Wstewter (Medin Conc.) 100% (160 µg/l) 100% (3.45 mg/l) Detection in Post- RO Effluent (Medin Conc.) 89% (75 µg/l) 100% (0.12 mg/l) Medin Removl Efficiency (Min.- Mx.) Reson for Selection Intermedite 62% (31 90%) Intermedite 88% Metl with lowest % rejection Only metl with medin post- RO conc. higher thn groundwter Commonly detected nion with intermedite rejection by RO B-72 NDMA N-nitrosmine Smll size Unchrged Very hydrophilic Very polr Chloroform DBP Smll size Slightly hydrophilic Non-polr Orgnic Bromochloromethne DBP Smll size Unchrged Hydrophilic Non-polr orgnic 96% (16 ng/l) 85% (0.4 µg/l) 94% (0.22 µg/l) 92% (4.5 ng/l) 56% (0.14 µg/l) 100% (0.11 µg/l) (85 99%) Intermedite 79% (30 95%) Intermedite 82% ( %) Intermedite 63% (-50 99%) Highest medin concentrtion nd high % detection in wstewter nd post-ro wter Toxicologicl concerns Hlomethnes were the most commonly detected DBP Represents hydrophobic compounds Potentilly bsorbing to membrne nd prtitioning into RO permete My be better indictor thn chloroform bsed on higher detection nd lower rejection by RO 66

232 B-73 Chemicl Indictor Chemicl Properties 1,4-Dichlorobenzene VOC Intermedite size Unchrged Hydrophobic Non-polr orgnic Crbmzepine Phrmceuticl Non-polr orgnic Modertely lrge sized Slightly hydrophobic EDTA Complexing gent Lrge size Negtively chrged Polr orgnic Diclofenc Phrmceuticl Acidic Lrge size Slightly hydrophobic Polr orgnic ND = Not detected Adopted from [36] Detection in Secondry Wstewter (Medin Conc.) 95% (0.81 µg/l) 97% (938 ng/l) 100% (2 µg/l) 100% (362 ng/l) Detection in Post- RO Effluent (Medin Conc.) 90% (0.2 µg/l) 0% (ND) 48% (0.5 µg/l) 0% (ND) Medin Removl Efficiency (Min.- Mx.) Reson for Selection Intermedite 84% (-20 95%) Good 99.8% ( %) Good 99.5% ( %) Good 99.6% ( ) Highest VOC concentrtion nd % detection in wstewter nd post-ro wter Very persistent in the environment Phrmceuticl with highest % detection nd concentrtion in wstewter Very well rejected by Ro membrnes Detected in ll wstewter smples t reltively high concentrtions Well rejected by Ro membrnes Detected in ll wstewter smples Represents cidic phrmceuticls 67

233 Tble 14. Chemicl Indictors of Recycled Wter Qulity for Western Austrli Chemicl Indictor Chemicl Group Detection in Secondry Wstewter (Medin Conc.) Boron Metlloid 100% (160 µg/l) Nitrte Inorgnic nion 100% (3.45 mg/l) NDMA N-nitrosmine 96% (16 ng/l) Chlorte Anion 37% (12.8 µg/l) 1,4-Dioxne* Neutrl orgnic 100% (0.52 µg/l) 1,4-Dichlorobenzene VOC 95% Non-polr orgnic (0.81 µg/l) Fluorene Polycyclic romtic 64% hydrocrbon (0.003 µg/l) 2,4,6-Trichlorophenol Phenol 64% (44.5 µg/l) Crbmzepine Phrmceuticl 97% Non-polr orgnic (938 ng/l) Estrone Hormone 48% (15 ng/l) EDTA Complexing gent 100% Lrge, polr orgnic (2 µg/l) Diclofenc Phrmceuticl 100% Acidic, polr orgnic (362 ng/l) Triflurlin Pesticide 91% (16 pg/l) Octdioxin Dioxin 67% (16 pg/l) ND = Not detected Adpted from [36] Detection in Post- RO Effluent (Medin Conc.) 89% (75 µg/l) 100% (0.12 mg/l) 92% (4.5 ng/l) 46% (12.7 µg/l) 28.5% (0.12 µg/l) 90% (0.2 µg/l) 19% (0.003 µg/l) 0% (ND) 0% (ND) 0% (ND) 48% (0.5 µg/l) 0% (ND) 0% (ND) 18% (5 pg/l) 68 B-74

234 Tble 15. UOSA Permit Limits Prmeter Limit Unit Flow 54 MGD E. coli < 2 number/100 ml Biologicl Oxygen Demnd mg/l Chemicl oxygen demnd 10.0 mg/l Turbidity 0.5 NTU Totl Suspended Solids 1.0 mg/l Totl Phosphorus 0.1 mg/l Surfctnts 0.1 mg/l MBAS 0.1 mg/l Totl Kjeldhl Nitrogen 1.0 mg/l Dissolved Oxygen > 5.0 mg/l Dechlorintion Chlorine Residul Non detect mg/l Adpted from [44,45] Tble 16. Microbil Removl Assessment for Millrd H. Robbins, Jr. Wter Reclmtion Plnt Log 10 Reduction Microorgnism Averge Product Wter Concentrtion 4.02 Clostridium perfringens 0.35 CFU/100 ml > 5.95 Fecl coliform ND > 5 E. coli ND > 5 Totl coliform ND 5.27 Enterococcus 0.45 CFU/100 ml 5.86 Coliphge 0.02 PFU/100 ml > 4.11 Enterovirus ND > 4 Cryptosporidium 0.04 cysts/100 L (1 of 14) Girdi 1.1 cysts/100 L (3 of 14) Adpted from [46] 69 B-75

235 Tble 17. Lnd use in the Occoqun Wtershed bsed on LANDSAT stellite imgery Lnd Use Acres Percent Agriculture 94, Brren/Trnsitionl Forest 160, Grsslnd 41, Wter 3,910 1 Residentil 51, Urbn/Industril 25,900 7 Totl 378, Adpted from [49] 70 B-76

236 Tble 18. Comprison of FCWA 2005 Lorton WTP nd 2010 Griffith WTP Influent nd Effluent Wter Qulity Dt 2005 Lorton Wter Tretment Plnt 2010 Griffith Wter Tretment Plnt Generl Prmeters Units Influent Effluent Influent Effluent Avg Mx Avg Mx Avg Mx Avg Mx Aggressive Index Number Units Ammoni s N mg/l < Bromide mg/l < Chloride mg/l Chlorine, Free mg/l Chlorine, Totl mg/l Color Units Dissolved Oxygen mg/l Fluoride mg/l < < Hrdness, Clcium mg/l Nitrte s N mg/l Nitrite s N mg/l < < ph Units Phosphte s Phosphorous mg/l < 0.1 < Specific Conductivity μmhos/cm Sulfte mg/l Temperture C Totl Alklinity mg/l Totl Dissolved Solids mg/l Totl Hrdness mg/l Totl Orgnic Crbon mg/l B-77

237 Totl Suspended Solids mg/l 9 35 < < 1 < 1 Turbidity NTU DBPs Bromte μg/l - - < 10 < < 5 6 Hlocetic Acids, Totl μg/l Trihlomethnes, Totl μg/l Tste-nd-Odor Indictors Tste Units Threshold Odor Number Units Adpted from [52] 72 B-78

238 REFERENCES [1] J. Crook Regultory Aspects of Direct Potble Reuse in Cliforni: An NWRI White Pper. Ntionl Wter Reserch Institute, Fountin Vlley, Clif. Dted April [2] Cliforni Deprtment of Public Helth (2008). Title 22, Cliforni Code of Regultions: Division 4. Environmentl Helth. Chpter 3. Recycling Criteri, to Dted August 5, [3] Legisltive counsel s digest Cliforni Sente Bill Sente Bill No. 918, Chpter 700. An ct to mend Sections nd of, nd to dd Chpter 7.3 (commencing with Section 13560) to Division 7 of the Wter Code. [4] Cliforni Deprtment of Helth Services (1996). Memorndum of Agreement Between the Deprtment of Helth Services nd the Stte Wter Resources Control Bord on Use of Reclimed wter ( MemorndumofAgreement.pdf). [5] Cliforni Deprtment of Public Helth (2008). Groundwter Rechrge Reuse DRAFT Regultion, August 5, Cliforni Deprtment of Public Helth, Drinking Wter Progrm, Scrmento, Cliforni. [6] CDM in ssocition with MWH. Drft Technicl Memorndum No. 4: MWD/LACSD Regionl Purified Wter Reuse Study Wter Qulity nd Tretment. Prepred for Metropolitn Wter District of Southern Cliforni nd Snittion Districts of Los Angeles County, dted Mrch 3, [7] Cliforni Deprtment of Public Helth (2009). Stte of Cliforni Division of Drinking Wter nd Mngement: Tretment Technology Report for recycled Wter. Dted December [8] H. Collins. Cliforni s Drft Criteri for Groundwter Rechrge with Reclimed Wter & Emerging Contminnt Control. Presented t 2008 Wter Qulity & Regultory Conference, Ontrio Clif., October 15, [9] S. Deshmukh, J.H. Clrk. Expnding to 100 MGD: The Next Phse of the Groundwter Replenishment System. In Proceedings to 2010 WteReuse Conference, Sn Diego, Mrch B-79

239 [10] T. Knoell, M. Ptel, E. Owens. Groundwter Replenishment System: Opertion from Pilot, Demonstrtion, nd Full-Scle Systems. In Proceedings 2010 AMTA Annul Conference nd Exposition, Sn Diego, July [11] Cliforni Regionl Wter Qulity Control Bord, Snt An Region Order No. R : Producer/User Wter Recycling Requirements for the Ornge County Wter District Interim Wter Fctory 21 nd Groundwter Replenishment System, Groundwter Rechrge nd Reuse t Tlbert Gp Sewter Intrusion Brrier nd Kremer/Miller Rechrge Bsins, Ornge County. [12] D.L. Burris nd R.L. Herndon Title 22 Engineering Report for the Groundwter Replenishment System: A Joint Project of the Ornge County Wter District nd Ornge County Snittion District, dted September [13] Personl communiction with Tom Knoell (OCWD), dted July 20, [14] M.V. Ptel, W. Dunivin. Why Operting Membrne Plnts Cn Drive You Nuts. In Proceedings 2010 AMTA Annul Conference nd Exposition, Sn Diego, July [15] Ornge County Wter District, Reserch nd Development Deprtment. Jnury Scle-Up of Microfiltrtion System in Municipl Wstewter Reclmtion. Finl Report: Electrotechnology Applictions for Potble Wter Production nd Protection of the Environment, Appendix 2.8 B, Tsk 2.8 B. Cliforni Energy Commission, Contrct #CEC [16] Ornge County Wter District, Reserch nd Development Deprtment. Mrch Deployment of Ultrviolet Disinfection Processes in Wter Reuse Applictions. USEPA Finl Report, Deslintion Reserch nd Innovtion Prtnership I. Federl Grnt Assistnce Number: XP [17] Ornge County Wter District, Reserch nd Development Deprtment. Jnury Disinfection Alterntives in Municipl Wstewter Reclmtion. Finl Report: Electrotechnology Applictions for Potble Wter Production nd Protection of the Environment, Appendix 2.5 B, Tsk 2.5 B. Cliforni Energy Commission, Contrct #CEC [18] Ornge County Wter District. Mrch Deployment of Ultrviolet Disinfection Processes in Wter Reuse Applictions. Finl Report to United Sttes Environmentl Protection Agency, Federl Grnt Assistnce Number: XP B-80

240 [19] EOI, Inc. (2000). Ornge County Wter District nd Ornge County Snittion District Groundwter Replenishment System Wter Qulity Evlution: Tsk 7: Conduct Risk Assessment. Finl Report submitted to OCWD nd OCSD, November [20] Ornge County Wter District, Reserch nd Development Deprtment. September Prediction of Orgnics Removl by RO membrnes. USEPA Finl Report, Deslintion Reserch nd Innovtion Prtnership I. Federl Grnt Assistnce Number: XP [21] Ornge County Wter District, Reserch nd Development Deprtment. Jnury Effects of Moleculr nd Environmentl Properties on Removl of Phrmceuticls, Endocrine Disruptors nd Disinfection Byproducts by Polymide Reverse Osmosis Membrnes. USEPA Finl Report, Deslintion Reserch nd Innovtion Prtnership II. Federl Grnt Assistnce Number: XP [22] Liboten, D.; Girlt, J.; Rllo, R.; Cohen, Y.; Girlt, F.; Ridgwy, H.F.; Rodriguez, G.; Phipps, D. Orgnic Compounds Pssge through RO Membrnes, Journl of Membrne Science (2007), doi: /j.memsci [23] D. Murbch. Drft Amended Engineering Report on the Production, Distribution nd Use of Reclimed Wter for Title 22 Irrigtion nd Industril Purposes from Phse IV of the West Bsin Wter Reclmtion Tretment Fcility. Prepred for West Bsin Municipl Wter District. Dted June 3, [24] City of Los Angeles. Personl communiction with Timeyin Dfeton on April 14, [25] City of Los Angeles Annul Monitoring Report for Hyperion Wste Wter Tretment Plnt. Anlysis of 5-Mile Effluent Qulity. Dted April 5, [26] West Bsin Municipl Wter District. Electric wter qulity dtbse for WBMWD Brrier Plnt. Personl communiction with Uzi Dniel on July 21, [27] McGovern, L.M., Dryden, F.D. West Bsin Wter Recycling Plnt: West Cost Bsin Brrier Project expnsion: Phse III Amended Engineering Report. Dted Mrch [28] West Bsin Municipl Wter District. Personl communiction with Uzi Dniel on July 21, [29] West Bsin Municipl Wter District, Crson, CA, December Investigtion of the Rejection Behvior of Trce Orgnic Compounds Using Advnced Seprtion Membrne Processes nd AOP. USEPA Finl Report, Deslintion Reserch nd Innovtion Prtnership II. Federl Grnt Assistnce Number: XP B-81

241 [30] J.E. Drewes, P. Xu, C. Bellon, M. Oedekoven, G. Amy, T.-U. Kim, U. Dniel. Rejection of Wstewter-Derived Micropollutnts in High-Pressure Membrne Applictions Leding to Indirect Potble Reuse: Effects of Membrne nd Micropollutnt Properties. Finl Report, Colordo School of Mines, Cliforni Energy Commission Contrct #CEC December [31] F. D. Dryden, T.A. Johnson. Title 22 Engineering Report for the Almitos Brrier Recycled Wter Project. Prepred by the Wter Replenishment District of Southern Cliforni. August [32] County Snittion Districts of Los Angeles. Long Bech Wter Reclmtion Plnt Annul Monitoring Report for Dted April 9, [33] County Snittion Districts of Los Angeles. Combined NPDES nd Wter Reuse Annul Monitoring Report for Long Bech Wter Reclmtion Plnt for April 8, [34] R.S. Trussel, R.Trussel, P. Fu, R. Seimk, K. Alexnder. Fcility Assessment Provides Significnt O&M Svings t the wter Replenishment District s Vnder Lns Wter Tretment Fcility. Proceedings 24 th Annul WteReuse Foundtion Symposium, Settle, September [35] F.D. Dryden. Amended Title 22 Engineering Report for the Almitos Brrier Recycled Wter Project. Prepred by the Wter Replenishment District of Southern Cliforni. My [36] Premiers Collbortive Reserch Progrm project (2009). Chrcterizing Treted Wstewter for Drinking Purposes Following Reverse Osmosis Tretment. Published by Deprtment of Helth, Western Austrli. ISBN [37] Cdee, K. Applying Leding Edge Technologies: Beenyup Groundwter Replenishment Project. Presented t 7 th IWA Leding Edge Technology Conference, Phoenix, Ariz., June 2 4, [38] Ntionl Helth nd Medicl Reserch Council Annul Report. Austrlin Government. [39] FCWA [40] Asno, T.; Burton, F.L.; Leverenz, H.L.; Tsuchihshi, R.; Tchobnoglous, G. Wter Reuse; Issues, Technologies, nd Applictions. Metclf & Eddy, AECOM press, McGrw Hill, New York B-82

242 [41] FCWA Annul Report on Wter Qulity. [42] [43] Rose, J. B., D. E. Huffmn, K. Riley, S. R. Frrh, J. O. Luksik, nd C. L. Hmnn Reduction of Enteric Microorgnisms t the Upper Occoqun Sewge Authority Wter Reclmtion Plnt. Wter Environ. Res. 73: [44] M.H. Robbins, Jr. & C.G. Ehlt Opertion nd Mintennce of the UOSA Wter Reclmtion Plnt. Journl Wter Pollution Control Federtion Vol. 57 (12): [45] [46] Wter qulity dtbse supplied by Robert Angelotti. Personl communiction, Februry 7, [47] A.C. Vn Den Bos A Wter Qulity Assessment of the Occoqun Reservoir nd Its Tributry Wtershed: Mster of Sciences Thesis to Virgini Polytechnic Institute nd Stte University [48] FCWA. My 5, News relese. [49] FCWA Source Wter Assessment Progrm: Finl Report, dted Jnury [50] Firfx County. Firfx County Comprehensive Pln, 2007 Edition Policy Pln Chespeke By Supplement, Adopted [51] Rose, J. B., D. E. Huffmn, K. Riley, S. R. Frrh, J. O. Luksik, nd C. L. Hmnn Reduction of Enteric Microorgnisms t the Upper Occoqun Sewge Authority Wter Reclmtion Plnt. Wter Environ. Res. 73: [52] FCWA Wter Qulity Anlyticl Reports B-83

243 APPENDIX C WATER QUALITY PARAMETERS, ANALYTICAL METHODS, AND TARGET CONCENTRATIONS

244 This ppendix describes the nlysis methods for ech of the wter qulity prmeters mesured in this project. EPA or Stndrd Methods (bbrevited s SM throughout this report, nd published by the Americn Public Helth Assocition) were used for most compounds. The hormones, endocrine disrupting compounds, nd the phrmceuticls nd personl cre products (PPCPs) do not currently hve stndrdized methods. Most of these compounds were nlyzed ccording to Nelson et l. (2011). However, different method ws used for the lkylphenol ethoxylte smples tken throughout the study, s well s for the steroid nd lkylphenol smples tken during 2012; Section C1 describes the nlyticl method used in 2012 for these three clsses of compounds. Section C2 provides tbles tht list the methods used for the routine wter qulity smples nd the AOP smples. Section C3 provides tbles tht list the methods, minimum required reporting levels, the regultory limits tht drove the nlysis, nd the nlyzing lbortory. C.1 ANALYTICAL METHOD FOR STEROIDS, ALKYLPHENOLS, AND ALKYLPHENOL ETHOXYLATES During 2010 nd 2011, the steroids nd lkylphenols were nlyzed ccording to Nelson et l. (2011). In 2010, the EPA relesed new method (539) for nlyzing steroids in drinking wter nd source wter. However, this method ws not pproprite for wstewter mtrices. Consequently, the method described below ws used for smples tken in 2012; this method provided lower reporting limits thn the previously-used method nd pplied to wider rnge of compounds. The new method dded estriol, equilin, testosterone nd ndrostenedione, nd removed progesterone, which hd never been detected in ny Districts smples over the threeyer period tht it ws smpled. This method ws lso used for ll lkylphenol ethoxylte smples tken throughout the study ( ). The AP nd APEO nlysis t SJCWQL used Shimdzu HPLC system equipped with two LC 10AD-vp metering pumps, DGU-14A degssing unit, nd SIL-HTc utosmpler unit. The mss spectrometer ws n Applied Biosystems API 5000 tndem mss spectrometer with n electrospry ioniztion (ESI) probe, which ws operted in both positive (APEO) nd negtive (AP) ESI modes. Two HPLC columns were used: Thermo Aqusil C18 HPLC column (50 x 2.1mm, 3 m prticle size) ws used for APs, nd Phenomenex Gemini C18 HPLC column (50 x 2.1 mm, 3 m prticle size) ws used for APEOs. The Steroid nlysis used Dionex HPLC system equipped with two Ultimte 3000 ternry pumps, n Ultimte 3000 degssing unit, n Ultimte 3000 HPLC column comprtment, nd n Ultimte 3000 utosmpler unit. The mss spectrometer ws n AB Sciex 5500 QTrp tndem mss spectrometer with n electrospry ioniztion (ESI) probe, which ws operted in both positive nd negtive ESI modes simultneously. A Phenomenex Kinetix XB-C18 HPLC column (50 x 2.1mm, 2.6 m prticle size) ws used. The first phse of the smple preprtion ws SPE, which used Phenomenex Strt -X crtridges (500 mg resin/6 cm 3 ) with Cliper Life Sciences Autotrce progrmmble SPE worksttion. The SPE system ws first clened by flushing with sequence of rinses: 15 ml ech of methnol, dichloromethne, nd methnol, followed by finl 40 ml flush with regent wter nd 3 min of ir-drying. The crtridges were then conditioned with progression of rinses: 7 ml of methnol, nd then 10 ml of regent wter. C-1

245 Prior to extrction, mixture of isotope lbeled nlog compounds ws dded to the effluent smples to fcilitte isotope dilution quntittion. Smples (500 ml) were pssed through the SPE crtridges, which were then wshed with 5 ml of regent wter, followed by 7.0 ml of 65% methnol solution (in regent wter) to remove polr interferences, dried with compressed ir for 25 min, nd eluted with 11 ml of methnol. The eluent volume ws reduced to dryness by strem of dry ir in n Orgnomtion Assocites N-Evp 111 nitrogen evportor, nd the finl volume ws brought up to 1 ml using methnol/wter (50:50). Three seprte nlyses were conducted on the sme smple. The AP nlysis used 3.0 μl of smple, nd compounds were seprted using grdient progrm with two solvents t combined flow rte of 0.4 ml/min. Solvent A ws 40 mg/l of mmonium cette, nd solvent B ws methnol. APEO nlysis used 2.0 μl of smple with two solvents t combined flow rte of 0.4 ml/min. Solvent for APEO nlysis were the sme s for AP nlysis. Steroid nlysis used 12 μl of smple, nd compounds were seprted using grdient progrm with two solvents t combined flow rte of 0.55 ml/min. Solvent A ws regent wter, nd solvent B ws cetonitrile. Additionlly, the steroid nlysis used post-hplc column infusion of NH 4 OH (2.0% in regent wter) to improve the chemicl ioniztion (0.05 ml/ min). Tble B1 provides the grdient profile used for ech mode. Tble C-1. LC Grdient Profiles Alkylphenols Alkylphenol Ethoxyltes Steroids Time (min) % of Solvent B in the Mobile Phse Time (min) % of Solvent B in the Mobile Phse Time (min) % of Solvent B in the Mobile Phse End 13.0 End End For the MS, AP nlysis used n ioniztion energy of -4500V nd temperture of 600ºC, wheres APEO nlysis used n ioniztion energy of 4500V nd temperture of 300ºC. Steroid nlysis used n ioniztion energy tht rpidly lternted between 4500 V nd -4500V, nd temperture of 500ºC. The probe height ws 5 mm. Other conditions on the instrument were s follows: gs 1 t 40 psi, gs 2 t 55 psi, curtin gs t 27, nd collision gs t setting of 6. Nitrogen ws used s the curtin, heter, nd collision gs. Multiple rection monitoring (MRM) trnsitions were used to identify ech of the compounds s shown in Tble B2. Chromtogrphiclly resolved nlytes were quntified by pek re to internl stndrd re rtios for ech specific prent/dughter mss trnsition s mesured by tndem mss spectrometry nd clculted by Anlyst softwre. C-2

246 Tble C-2. MRM Trnsitions Compound ESI Mode Quntittion Trnsition 4-Nonylphenol Negtive tert octylphenol Negtive Nonylphenol monoethoxylte Positive Nonylphenol diethoxylte Positive Octylphenol monoethoxylte Positive Octylphenol diethoxylte Positive Estrone (E1) Negtive Estrdiol (E2) Negtive Ethinylestrdiol (EE2) Negtive Equilin (EQ) Negtive Estriol (E3) Negtive Testorsterone Positive Androstenedione Positive C-3

247 C.2 ANALYTICAL METHOD FOR ROUTINE WATER QUALITY SAMPLES AND AOP SAMPLES The tbles in this section list the prmeters mesured by the Districts lbortories during routine wter qulity smpling, s well s during AOP testing. For ech prmeter, the method nd reporting limit re provided. Tbles C-3 through C-5 list the nlyticl methods nd reporting limits for endocrine disrupting compounds (EDCs) nd phrmceuticls nd personl cre products (PPCPs), which were only mesured in the AOP experiments; the nitrosmines nd 1,4- dioxne; nd the generl wter qulity prmeters. Tble C-3. EDCs nd PPCPs Anlyzed in AOP Experiments Prmeters Method Reporting Limit (ng/l) 17-Alph Ethinylestrdiol See Section C Bet Estrdiol See Section C Nonylphenol (tech mix) See Section C tert Octylphenol See Section C1 5.0 Acetminophen Nelson et l. (2011) 10 Androstenedione See Section C1 0.5 Azithromycin Nelson et l. (2011) 10 Bisphenol A Nelson et l. (2011) 10 Cffeine Nelson et l. (2011) 10 DEET Nelson et l. (2011) 10 Dilntin (Phenytoin) Nelson et l. (2011) 10 Equilin See Section C1 0.5 Estriol See Section C1 0.5 Estrone See Section C Gemfibrozil Nelson et l. (2011) 10 Ibuprofen Nelson et l. (2011) 10 Iopromide Nelson et l. (2011) 30 Meprobmte Nelson et l. (2011) 10 Nonylphenol diethoxylte See Section C1 25 Nonylphenol monoethoxylte See Section C1 25 Octylphenol diethoxylte See Section C1 25 Octylphenol monoethoxylte See Section C1 25 Progesterone See Section C1 1.0 Sucrlose Nelson et l. (2011) 40 Sulfmethoxzole Nelson et l. (2011) 10 TCEP Nelson et l. (2011) 10 Testosterone See Section C1 0.5 Triclosn Nelson et l. (2011) 10 C-4

248 Tble C-4. Nitrosmines nd 1,4-Dioxne Anlyzed in Routine nd AOP Smples Reporting Limits Prmeter Method Units Secondry, UF MBR RO Permete RO Concentrte AOP 1,4-Dioxne EPA 3535/8270C g/l * 0.4 NDMA EPA 1625 ng/l * NDEA EPA 1625 ng/l * NDPA EPA 1625 ng/l * NDBA EPA 1625 ng/l * NMEA EPA 1625 ng/l * NPIP EPA 1625 ng/l * NPYR EPA 1625 ng/l * *Not mesured. C-5

249 Tble C-5. Anlyticl Methods for Routine Wter Qulity Smples C-6 Reporting Limits Prmeters Method Units Secondry, UF MBR RO Permete RO Concentrte AOP Alklinity SM 2320B (Low) mg/l Aluminum EPA g/l * Ammoni SM 4500 NH3 C mg/l Brium EPA g/l * Boron EPA mg/l * Clcium EPA mg/l * Chloride EPA mg/l * COD SM 5220C (SMicro) mg/l Fluoride SM 4500 F C mg/l * Iron EPA mg/l * Mgnesium EPA mg/l * Nitrte SM 4500 NO3 E mg/l Nitrite SM 4500 NO2 B mg/l Orthophosphte SM4500P-E mg/l * ph SM 4500 H+ B ph units * * * * * Potssium EPA mg/l * scod SM 5220C (SMicro) mg/l 10 * * * * Silic EPA mg/l * Sodium EPA mg/l * Strontium EPA g/l ,000 * Sulfte EPA mg/l * TDS SM 2540C mg/l * TKN SM 4500 NH3 C mg/l TOC SM 5310B mg/l TSS SM 2540D mg/l * * * * Turbidity SM 2130B NTU * * * *Not mesured.

250 C.3 ANALYTICAL METHODS FOR TITLE 22+ SAMPLES The tbles in this section list the nlyzing lbortory, the method, the reporting limits, the trget concentrtion for this project, nd limits or other levels considered in setting the trget concentrtion. Compounds were nlyzed by one of three lbortories: MWD, the Districts (referred to s CSD in the tbles below), or Eurofins Eton Anlyticl (referred to s EEA in the tbles below). It should be noted tht the originl contrct for nlysis ws with MWH Lbortories, which were cquired by Eurofins Scientific prtwy through the project. The lbortory fcility ws the sme for ll smples, but the nme of the lbortory chnged to Eurofins Eton Anlyticl. Trgets for wter qulity were bsed on requirements for groundwter rechrge, nd were set to the lowest of the following vlues for ech prmeter: EPA primry mximium contminnt levels (MCLs) nd secondry MCLs for drinking wter, CDPH primry nd secondry MCLs, nd notifiction levels (NLs) for drinking wter, CDPH DGRR levels for totl nitrogen, TOC, nd turbidity, locl bsin pln objectives for Western Sub-bsin of the Min Sn Gbriel Bsin, SWRCB monitoring trigger levels for chemicls of emerging concern (note tht these levels re guidelines, not regultory requirements). In ddition to these limits, removl requirements for N-nitrosodimethylmine (NDMA) nd 1,4- dioxne from the 2008 CDPH DGRR were pplied to the AOP portion of the study; the 2011 DGRR (relesed prtwy through this project) eliminted the NDMA requirement, but it ws kept for this project. In the following tbles, BPO refers to bsin pln objective, MTL refers to monitoring trigger level from the 2010 SWRCB report, NL refers to notifiction level, PMCL refers to primry mximum contminnt level, RL refers to reporting level, nd SMCL refers to secondry mximum contminnt level. Note tht some of the criteri overlp; for exmple, ll CDPH MCLs pply to the bsin pln objectives. For simplicity, these only the unique vlues re included in the tbles in this ppendix. C-7

251 Tble C-6. Inorgnic Smples (Generl Physicl nd Minerl) C-8 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Alklinity, Totl EEA SM 2320B mg/l 2 NA Ammoni s N EEA EPA mg N/L 0.05 NA Asbestos EEA EPA MFL Boron EEA EPA mg/l Bromide EEA EPA ug/l 5 NA Clcium EEA EPA mg/l 1 NA Chloride EEA EPA mg/l Color EEA SM 2120B ACU Conductivity EEA SM 2510B umho/cm 2 NA Cynide EEA SM 4500CN- mg/l Fluoride EEA SM 4500F-C mg/l Foming Agents EEA SM 5540C mg/l Hrdness, Totl EEA SM 2340B mg/l 3 NA Mgnesium EEA EPA mg/l 0.1 NA Nitrte EEA EPA mg N/L Nitrte + Nitrite** EEA EPA mg N/L Nitrite EEA EPA mg N/L Odor EEA SM 2150B TON Orgnic nitrogen CSD SM 4500 NH3 mg N/L 1 NA Perchlorte EEA EPA 314 ug/l ph EEA SM 2330B Units Potssium EEA EPA mg/l 1 NA Sodium EEA EPA mg/l 1 NA Sulfte EEA EPA mg/l TDS EEA EPA mg/l 10 NA Totl Orgnic Crbon CSD SM 5310C mg/l Totl Phosphorus EEA SM 4500P-E mg/l 0.02 NA Turbidity EEA EPA NTU UVT, 254 nm CSD SM 5910 % 0 NA *Smples with detections of cynide were nlyzed with mnul distilltion, which hd lower reporting limit (0.005 mg/l) thn SM 4500CN-F. **CDPH DGRR lso hs limit of 10 mg N/L for totl nitrogen.

252 Tble C-7. Inorgnic Smples (Trce Metls) C-9 Test EPA CDPH Trget Constituent Lb Method Units RL PMCL SMCL PMCL SMCL NL DRGG BPO MTL Conc Aluminum EEA EPA g/l , Antimony EEA EPA g/l Arsenic EEA EPA g/l Brium EEA EPA g/l 2 2,000 1,000 1,000 1,000 Beryllium EEA EPA g/l Cdmium EEA EPA g/l Chromium (Totl) EEA EPA g/l Hexvlent Chromium EEA EPA g/l NA Copper EEA EPA g/l 2 1,300 1,000 1,300 1,000 1, Iron EEA EPA mg/l Led EEA EPA g/l Mngnese EEA EPA g/l Mercury EEA EPA g/l Nickel EEA EPA g/l Selenium EEA EPA g/l Silver EEA EPA g/l Thllium EEA EPA g/l Vndium EEA EPA g/l Zinc EEA EPA g/l 20 5,000 5,000 5,000 5,000

253 Tble C-8. Rdiologicl Smples Test EPA CDPH Trget Constituent Lb Method Units RL PMCL SMCL PMCL SMCL NL DRGG BPO MTL Conc Gross Alph EEA EPA pci/l Gross Bet EEA EPA pci/l mrem/yr 4 mrem/yr Rdium 226 EEA EPA pci/l NA Rdium 228 EEA EPA pci/l NA Combined Rdium 226, 228 EEA EPA pci/l Rdon EEA SM 7500RN pci/l 50 NA Strontium-90 EEA EPA pci/l Tritium EEA EPA pci/l ,000 20,000 20,000 Urnium EEA EPA pci/l C-10

254 Tble C-9. Semi-voltile Orgnic Compounds C-11 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Benzo (A) Pyrene EEA EPA g/l Di (2-Ethylhexyl) Adipte EEA EPA g/l Di (2-Ethylhexyl) Phthlte EEA EPA g/l ,4,6-Trichlorophenol CSD EPA 625 g/l 10 NA P-Chloro-m-Cresol CSD EPA 625 g/l 0.2 NA 2-Chlorophenol CSD EPA 625 g/l 5 NA 2,4-Dichlorophenol CSD EPA 625 g/l 5 NA 2-Nitrophenol CSD EPA 625 g/l 10 NA 4-Nitrophenol CSD EPA 625 g/l 10 NA 2,4-Dinitrophenol CSD EPA 625 g/l 5 NA 4,6-Dinitro-o-Cresol CSD EPA 625 g/l 2.5 NA Benzidine CSD EPA 625 g/l 5 NA Hexchloroethne CSD EPA 625 g/l 1 NA Bis (2-chloroethyl) ether CSD EPA 625 g/l 2 NA 2-chloronphthlene CSD EPA 625 g/l 10 NA 3,3'-dichlorobenzidine CSD EPA 625 g/l 5 NA 2,4-dinitrotoluene EEA EPA g/l 0.1 NA 2,6-dinitrotoluene EEA EPA g/l 0.1 NA 1,2-diphenylhydrzine CSD EPA 625 g/l 1 NA 4-chlorophenyl phenyl ether CSD EPA 625 g/l 5 NA

255 Tble C-9b. Semi-voltile Orgnic Compounds (Continued) EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc 4-bromophenyl phenyl ether CSD EPA 625 g/l 5 NA Bis (2-chloroisopropyl) ether CSD EPA 625 g/l 2 NA Bis (2-chloroethoxy) methne CSD EPA 625 g/l 5 NA Isophorone EEA EPA g/l 0.5 NA Nitrobenzene CSD EPA 625 g/l 1 NA Bis (2-ethylhexyl) phthlte EEA EPA g/l 0.6 NA Butyl benzyl phthlte EEA EPA g/l 0.5 NA Di-n-butyl phthlte EEA EPA g/l 1 NA Di-n-octyl phthlte EEA EPA g/l 0.1 NA Diethyl phthlte EEA EPA g/l 0.5 NA Dimethyl phthlte EEA EPA g/l 0.5 NA C-12

256 Tble C-10. Voltile Orgnic Compounds C-13 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Benzene EEA EPA g/l Bromobenzene EEA EPA g/l 0.5 NA Bromochloromethne EEA EPA g/l 0.5 NA Bromodichloromethne EEA EPA g/l 0.5 NA Bromoform EEA EPA g/l 0.5 NA Bromomethne (Methyl bromide) EEA EPA g/l 0.5 NA sec-butylbenzene EEA EPA g/l n-butylbenzene EEA EPA g/l tert-butylbenzene EEA EPA g/l Crbon Tetrchloride EEA EPA g/l Chlorobenzene EEA EPA g/l Chlorodibromomethne EEA EPA g/l 0.5 NA Chloroethne EEA EPA g/l 0.5 NA Chloroform EEA EPA g/l 0.5 NA Chloromethne (methyl chloride) EEA EPA g/l 0.5 NA 2-Chlorotoluene or o-chlorotoluene EEA EPA g/l Chlorotoluene or p-chlorotoluene EEA EPA g/l Dibromomethne EEA EPA g/l 0.5 NA 1,2-Dichlorobenzene EEA EPA g/l ,3-Dichlorobenzene EEA EPA g/l

257 Tble C-10b. Voltile Orgnic Compounds (Continued) C-14 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc 1,4-Dichlorobenzene EEA EPA g/l ,2-Dichloroethne EEA EPA g/l ,1-Dichloroethne EEA EPA g/l ,1-Dichloroethene EEA EPA g/l cis-1,2-dichloroethene EEA EPA g/l trns-1,2-dichloroethene EEA EPA g/l Dichlorodifluoromethne (Freon12) EEA EPA g/l 0.5 1,000 1,000 1,2-Dichloropropne EEA EPA g/l ,3-Dichloropropne EEA EPA g/l 0.5 NA 2,2-Dichloropropne EEA EPA g/l 0.5 NA 1,1-Dichloropropene EEA EPA g/l 0.5 NA 1,3-Dichloropropene EEA EPA g/l cis-1,3-dichloropropene EEA EPA g/l 0.5 NA trns-1,3-dichloropropene EEA EPA g/l 0.5 NA ETBE (Ethyl tertiry butyl ether) EEA EPA g/l 3 NA Ethylbenzene EEA EPA g/l Hexchlorobutdiene EEA EPA g/l 0.5 NA Isopropylbenzene EEA EPA g/l 0.5 NA p-isopropyltoluene EEA EPA g/l 0.5 NA Methylene Chloride (dichloromethne) EEA EPA g/l MTBE EEA EPA g/l Nphthlene EEA EPA g/l n-propylbenzene EEA EPA g/l Styrene EEA EPA g/l

258 Tble C-10c. Voltile Orgnic Compounds (Continued) C-15 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc TAME (Tertiry myl methyl ether) EEA EPA g/l 3 NA 1,1,1,2-Tetrchloroethne EEA EPA g/l 0.5 NA 1,1,2,2-Tetrchloroethne EEA EPA g/l Tetrchloroethene EEA EPA g/l Toluene EEA EPA g/l 0.5 1, ,2,3-Trichlorobenzene EEA EPA g/l 0.5 NA 1,2,4-Trichlorobenzene EEA EPA g/l ,1,1-Trichloroethne EEA EPA g/l ,1,2-Trichloroethne EEA EPA g/l Trichloroethene EEA EPA g/l Trichlorofluoromethne EEA EPA g/l ,2,3-Trichloropropne EEA EPA 524.2m g/l ,1,2-Trichloro-1,2,2-trifluoroethne EEA EPA g/l 0.5 1,200 1,200 (Freon 113) 1,200 1,3,5-Trimethylbenzene EEA EPA g/l ,2,4-Trimethylbenzene EEA EPA g/l Vinyl Chloride EEA EPA g/l Xylenes EEA EPA g/l 1 10,000 1,750 1,750 TOTAL THMs EEA EPA g/l Acrolein CSD EPA 624 g/l 2 NA Acrylonitrile CSD EPA 624 g/l 2 NA 2-chloroethyl vinyl ether EEA EPA g/l 0.5 NA

259 Tble C-11. Orgnochlorine Pesticides C-16 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Alchlor EEA EPA g/l Aldrin EEA EPA g/l 0.05 NA Chlordne EEA EPA 505 g/l Chlorothnlonil EEA EPA g/l 0.1 NA Dieldrin EEA EPA g/l 0.2 NA Endrin EEA EPA g/l Heptchlor EEA EPA 505 g/l Heptchlor Epoxide EEA EPA 505 g/l Hexchlorobenzene EEA EPA g/l Hexchlorocyclopentdiene EEA EPA g/l Lindne EEA EPA g/l Methoxychlor EEA EPA g/l Polychlorinted Biphenyls EEA EPA 505 g/l Aroclor-1016 (PCB-1016) EEA EPA 505 g/l 0.1 NA Aroclor-1221 (PCB-1221) EEA EPA 505 g/l 0.1 NA Aroclor-1232 (PCB-1232) EEA EPA 505 g/l 0.1 NA Aroclor-1242 (PCB-1242) EEA EPA 505 g/l 0.1 NA Aroclor-1248 (PCB-1248) EEA EPA 505 g/l 0.1 NA Aroclor-1254 (PCB-1254) EEA EPA 505 g/l 0.1 NA Aroclor-1260 (PCB-1260) EEA EPA 505 g/l 0.1 NA

260 Tble C-11b. Orgnochlorine Pesticides (Continued) EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Propchlor EEA EPA g/l Toxphene EEA EPA 505 g/l ,4'-DDT EEA EPA g/l 0.1 NA 4,4'-DDE EEA EPA g/l 0.1 NA 4,4'-DDD EEA EPA g/l 0.1 NA Alph-endosulfn EEA EPA g/l 0.1 NA Bet-endosulfn EEA EPA g/l 0.1 NA Endosulfn sulfte EEA EPA g/l 0.1 NA Endrin ldehyde EEA EPA g/l 0.1 NA Delt-BHC EEA EPA g/l 0.1 NA C-17

261 Tble C-12. Orgnochlorine Herbicides EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Bentzon (Bsgrn) EEA EPA g/l ,4-D EEA EPA g/l Dlpon EEA EPA g/l Dicmb EEA EPA g/l 0.1 NA Dinoseb EEA EPA g/l Pentchlorophenol EEA EPA g/l Pichlorm EEA EPA g/l Silvex (2,4,5-TP) EEA EPA g/l C-18 Tble C-13. Fumignts EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Ethylene dibromide (EDB) EEA EPA g/l Dibromochloropropne (DBCP) EEA EPA g/l

262 Tble C-14. Crbmte Pesticides EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Diuron EEA EPA 532 g/l 1 NA Aldicrb EEA EPA g/l 0.5 NA Aldicrb sulfone EEA EPA g/l 0.5 NA Aldicrb sulfoxide EEA EPA g/l 0.5 NA Bygon (Propoxur) EEA EPA g/l 0.5 NA Crbofurn EEA EPA g/l Crbryl EEA EPA g/l 0.5 NA 3-hydroxycrbofurn EEA EPA g/l NA Methomyl EEA EPA g/l 0.5 NA Oxmyl EEA EPA g/l C-19

263 Tble C-15. Miscellneous Smples C-20 Test EPA CDPH Trget Constituent Lb Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Diqut EEA EPA 547 g/l Endothll EEA EPA g/l Glyphoste EEA EPA g/l Prqut EEA EPA 547 g/l 2 NA Polynucler Aromtic Hydrocrbons EEA EPA NA Acenphthene EEA EPA g/l 0.1 NA Fluornthene EEA EPA g/l 0.1 NA Benzo () nthrcene EEA EPA g/l 0.05 NA Benzo (b) fluornthene EEA EPA g/l 0.02 NA Benzo (k) fluornthene EEA EPA g/l 0.02 NA Chrysene EEA EPA g/l 0.02 NA Acenphthylene EEA EPA g/l 0.1 NA Anthrcene EEA EPA g/l 0.02 NA 1,12-benzoperylene EEA EPA g/l 0.05 NA Fluorene EEA EPA g/l 0.05 NA Phennthrene EEA EPA g/l 0.04 NA 1,2,5,6-dibenznthrcene EEA EPA g/l 0.05 NA Indeno (1,2,3-cd) pyrene EEA EPA g/l 0.05 NA Pyrene EEA EPA g/l 0.05 NA 2,3,7,8-TCDD Dioxin EEA EPA 1613 pg/l

264 Tble C-16. Nitrogen/Phosphorus Pesticides C-21 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Atrzine EEA EPA g/l Bromcil EEA EPA g/l 0.2 NA Butchlor EEA EPA g/l 0.05 NA Dizinon EEA EPA g/l Dimethote EEA EPA g/l 0.1 NA Mlthion EEA EPA g/l 0.1 NA Metolchlor EEA EPA g/l 0.05 NA Metribuzin EEA EPA g/l 0.05 NA Molinte EEA EPA g/l Prometryn EEA EPA g/l 0.05 NA Simzine EEA EPA g/l Thiobencrb (Bolero) EEA EPA g/l

265 Tble C-17. Other Chemicls C-22 Test EPA CDPH Trget Constituent Lb Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc -Benzene Hexchloride (-BHC) EEA EPA g/l 0.1 NA b-benzene Hexchloride (b-bhc) EEA EPA g/l 0.1 NA 2,4-Dimethylphenol EEA EPA 528 g/l 0.2 NA 1,4-Dioxne CSD EPA 8270M g/l Diphenmide EEA EPA 8140 g/l 0.5 NA Ethion EEA EPA 8140 g/l 0.5 NA Formldehyde EEA EPA 556 g/l Isopropyl N (3-Chlorophenyl) EEA EPA 8321 g/l 2 Crbmte (CIPC) NA Methyl Isobutyl Ketone (MIBK) EEA EPA g/l Methyl Prthion EEA EPA g/l 0.5 NA Prthion EEA EPA g/l 0.1 NA Pentchloronitro-benzene EEA EPA 8081 g/l 0.05 NA Phenol EEA EPA g/l 0.2 NA Trithion EEA EPA g/l 0.05 NA Cptn EEA EPA g/l 0.05 NA Chloropicrin EEA EPA g/l 0.5 NA Tert butyl lcohol EEA EPA 524.2m g/l Crbon disulfide EEA EPA g/l Chlorte EEA EPA g/l Ethylene glycol EEA GC-MS g/l 40 14,000 14,000 HMX EEA EPA 529 g/l Isopropyl benzene EEA EPA g/l RDX EEA LC-MS-MS g/l ,4,6-Trinitrotoluene (TNT) EEA EPA 529 g/l N-Nitrosodiphenylmine CSD EPA 625 g/l 1 NA

266 Tble C-18. Microbiology Test EPA CDPH Trget Constituent Lb Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Heterotrophic Plte EEA SM 9215B CFU/ml 1 Counts NA Totl Coliforms EEA SM 9221B* MPN/100 ml 1.1 NA Fecl Coliforms EEA SM 9221B* MPN/100 ml 1.1 NA E. coli EEA SM 9221B* MPN/100 ml 2 NA Cryptosporidium MWD EPA 1623 Oocysts/10L 0.1 NA Girdi MWD EPA 1623 Cysts/10L 0.1 NA Enteric Viruses (Totl Culturble Virus) MWD ICR 5-96 MPN/100 L *SM 9223B ws used for totl nd fecl coliform smples tken on My 15, 2012, nd for E. coli smples tken on My 15 nd 22, NA C-23 Tble C-19. Hormones nd Industril Endocrine Disrupting Compounds Test EPA CDPH Trget Constituent Lb Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc 17 -Estrdiol CSD * ng/l Bisphenol A CSD * ng/l , ,000 Nonylphenol CSD * ng/l , ,000 Nonylphenol Polyethoxltes CSD * ng/l 25 NA Octylphenol CSD * ng/l 25 50, ,000 Octylphenol Polyethoxltes CSD * ng/l 25 NA Polybrominted Diphenyl Ethers EEA EPA 527 ug/l NA *There is no EPA or Stndrd Method for hormones nd lkylphenols. Bisphenol A, nonylphenol, nd octylphenol were nlyzed ccording to Nelson et l. (2011). The lkylphenol ethoxyltes nd 17b-estrdiol were nlyzed ccording to the method described t the beginning of this ppendix.

267 Tble C-20. Phrmceuticls, Personl Cre Products, nd Other Wstewter Indictors C-24 EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc Acetminophen CSD * ng/l , ,000 Azithromycin CSD * ng/l 10 3,900 3,900 Crbmzepine CSD * ng/l 10 1,000 1,000 Dilntin CSD * ng/l 25 N/A NA Gemfibrozil CSD * ng/l 10 45,000 45,000 Ibuprofen CSD * ng/l 10 34,000 34,000 Meprobmte CSD * ng/l , ,000 Sulfmethoxzole CSD * ng/l 10 35,000 35,000 Triclosn CSD * ng/l DEET CSD * ng/l 10 2,500 2,500 Cffeine CSD * ng/l Iopromide CSD * ng/l , ,000 TCEP CSD * ng/l 10 2,500 2,500 Sucrlose CSD * ng/l 40 N/A NA *There is no EPA or Stndrd Method for these compounds, which were nlyzed ccording to Nelson et l. (2011).

268 Tble C-21. SWRCB Surrogte Prmeters EPA CDPH Trget Constituent Lb Test Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc DOC CSD SM 5310B mg/l 0.5 NA Chlorine residul CSD SM 4500 Cl G mg/l 0.05 NA Tble C-22. DBPs nd Nitrosmines C-25 Test EPA CDPH Trget Constituent Lb Method Units RL PMCL SMCL PMCL SMCL NL DGRR BPO MTL Conc HAA5 MWD SM 6251B g/l N-Nitrosodimethylmine (NDMA) CSD EPA 1625 ng/l N-Nitrosodiethylmine (NDEA) CSD EPA 1625 ng/l N-Nitrosodi-n-propylmine (NDPA) CSD EPA 1625 ng/l N-Nitrosopyrollidine (NPYR) CSD EPA 1625 ng/l 2 20 NA N-Nitrosomethylethylmine (NMEA) CSD EPA 1625 ng/l 2 NA N-Nitrosopiperidine (NPIP) CSD EPA 1625 ng/l 2 NA N-Nitroso-n-butylmine (NDBA) CSD EPA 1625 ng/l 2 NA

269 APPENDIX D MEMBRANE AUTOPSY REPORTS

270 Membrne Autopsy Report Prepred for: Snittion Districts of Los Angeles County Envirosoft WO # LACSD PO # My 18, 2011 Rev. 1 Envirosoft Corportion 3637 Motor Avenue, Suite 360 Los Angeles, CA Tel.: 1 (310) Emil: info@envirosoft.net Web: D-1

271 Synopsis Los Angeles County Snittion Districts (LACSD) provided four sets of Hydrnutics ESPA (Low Pressure RO) membrne elements to Envirosoft for nlysis. Two of the elements were the led (SN ) nd til (SN ) RO elements from LACSD pilot UF-RO system, while the remining two were the led (SN ) nd til (SN ) RO elements from LACSD pilot MBR-RO system. Exmintions of the submitted RO membrne elements reveled no visully-observble evidence of physicl dmge. Fiberglss wrps, end cps, brine sels, nd permete tubes ppered to be in good condition. Feed nd permete spcers nd glue lines were lso in stisfctory mechnicl condition. Performnce testing of full RO elements nd membrne smple coupons reveled lower thn norml membrne productivities. For the UF-RO system, the til RO element hd 50% less productivity thn the led element. For the MBR-RO system, the led element hd slightly lower (17%) productivity thn the til element. Productivity performnce of the RO membrne elements were ll well below mnufcturer specifictions by 33% or more, prticulrly the til RO element of the UF-RO system (66% below mnufcturer specifictions). Wter permebility vlues were mostly below mnufcturer specifictions, with the membrne smple coupon from the UF-RO system til RO element hving the lowest wter permebility (43% below mnufcturer specifictions). Internl visul exmintions, opticl imging, light microscope nlysis, FTIR nlysis, nd SEM-EDS nlysis indicted the presence of thin lyer of brown foulnt mteril on the membrne surfces of ll membrne elements, with the til RO element from the UF-RO system ppering to be most fouled. The foulnt lyers were composed of both orgnic nd inorgnic mterils (with silicon, clcium, iron, nd possibly sulfur s primry inorgnic constituents). Biologicl exmintion reveled trce grm-positive bcteri in the led RO element of the UF- RO system nd possible fungi in the led RO element of the MBR-RO system. Results of performnce testing of membrne elements nd membrne smple coupons reveled lower thn norml levels of slt rejection ( percentge points below the RO element mnufcturer specifiction). Fujiwr test ws positive for smples tken from ll of the RO membrne elements, except for those from the UF-RO system til RO element. Positive Fujiwr test results were indictive of membrne hlogention due to membrne exposure to hlogens (i.e., chlorine). It is noted tht extended membrne exposure to chlormine (NH 2 Cl) my led to enhnced membrne hlogention when in the presence of Fe(II) ions 1. Preliminry ssessments of membrne clening suggest tht foulnt mterils cn be removed to recover RO membrne permebility to within or bove mnufcturer s specifictions. Upon membrne clening, however, slt pssge (i.e., slt trnsport coefficient) ws significntly elevted (by up to % nd % bove mnufcturer specifictions for the membrne smples from the UF-RO nd MBR-RO systems, respectively), suggesting tht hlogented membrne res were exposed upon the removl of foulnt mterils. 1 C.J. Gbelich, J.C. Frnkin, F.W.Gerringer, K.P. Ishid, I.H. Suffet, Enhnced oxidtion of polymide membrnes using monochlormine nd ferrous iron, J. Membr. Sci. 258 (2005) D-2

272 Contents Membrne Autopsy Report... i Synopsis... 1 Contents Work Sttement Summry of Results & Anlysis Membrne Autopsy Results Externl visul exmintion Membrne element performnce Membrne coupon smpling nd storge Opticl Imging Fujiwr test FTIR nlysis Light Microscope Anlysis nd Bcteri Grm Stining Test SEM-EDS nlysis Membrne smple coupons performnce Other tests Membrne Scling Tendency Conclusions Appendix Wter qulity dt D-3

273 1. Work Sttement Los Angeles County Snittion Districts (LACSD) nd Metropolitn Wter District of Southern Cliforni (MWDSC) hve been evluting dvnced tretment of the effluent from the Joint Wter Pollution Control Plnt (JWPCP). Two different tretment processes were pilot tested in prllel, utilizing n UF-RO pilot system (UF: 0.04 m, PVDF, Memcor, Siemens) nd n MBR- RO pilot system (MBR: 0.04 m, PVDF, ZeeWeed 500C, GE). Ech pilot system employed n RO unit with totl of 21 RO membrne elements (Hydrnutics ESPA2-4040), rrnged in 2:1 rry configurtion with 7 elements per series per stge. In ech RO unit, ntisclnt tretment (King Lee PreTret Plus 0100) nd RO feed wter ph djustment (to ph ~6.5 with sulfuric cid) were employed to mitigte membrne minerl scling. Chloromine residul (3-4 ppm) ws mintined in the RO feed strems in order to control biofouling. Ech RO unit ws operted t trget wter recovery level of 85%. Envirosoft ws retined by LACSD to mnge the utopsy of four RO elements from the pilot systems. Both the MF-RO nd the MBR-RO pilot systems were shut down on April 4, Two representtive RO membrne elements ( led element from the 1st RO unit stge nd the til element from the 2nd RO unit stge) from ech pilot system were removed nd provided to Envirosoft. This report summrizes the membrne utopsy results. 3 D-4

274 2. Summry of Results & Anlysis 2.1. Membrne Autopsy Results The pilot UF-RO nd MBR-RO systems were shut down in the morning of April 4, From the RO unit of ech system, led RO membrne element in the 1 st RO unit stge nd the til membrne element in the 2 nd RO unit stge were removed from the RO pressure vessels nd submitted for utopsy. The RO elements were ll Hydrnutics ESPA (Size: 4 x 40 ). Tble 1. Submitted RO membrne elements. No System RO Element Position Seril No. (SN) 1 UF-RO Led UF-RO Til MBR-RO Led MBR-RO Til Externl visul exmintion Element weight The RO elements were weighed prior to the utopsy given tht RO element weight is often indictive of the degree of fouling. The led (SN ) nd til (SN ) RO elements from the UF-RO system were of 9 pounds weight ech. The led (SN ) nd til (SN ) RO elements from the MBR-RO system were of weights 9 nd 8 pounds, respectively. New RO elements of this type typiclly weigh 7-9 pounds. Fiberglss wrp The outer fiberglss csing of the membrne elements ppered to be in good condition, with no pprent sign of physicl dmge. They ppered to be reltively clen (Fig. 1), except for the til RO element from the UF-RO system (Fig. 2). Brine sel The brine sels were inspected on site. They were in good condition nd showed no signs of dmge tht could llow bypss of the NF/RO concentrte wter round the spirl wound membrne scrolls. End-cps / Anti-telescoping device (ATD) ATDs re designed to prevent telescoping of element leves t norml differentil pressures. There were no visible signs of physicl dmge (Fig. 3). Permete tube There ws no visible physicl dmge on the ends of the permete tubes tht could llow by-pss of feed wter (Fig. 3). 4 D-5

275 () UF-RO System Led RO Element SN (b) UF-RO System Til RO Element SN (c) MBR-RO System Led RO Element SN (d) MBR-RO System Til RO Element SN Figure 1. Photogrph of submitted RO membrne elements. UF-RO System Til RO Element SN Figure 2. Photogrph (tken on site) of the til RO element from the UF-RO system. Figure 3. Photogrphs of the front nd rer ends of the led nd til RO elements. 5 D-6

276 Membrne element performnce Performnce the RO elements ws tested t 15% wter recovery nd net driving pressure of psig, employing de-chlorinted city wter (~1000 S). The normlized permete flow nd slt rejection of the membrne element represents the overll (verge) performnce of the entire membrne element, including the membrne sheets, the effect of chnnel spcers, s well s the integrity of internl element flow connections nd fluid chnnels. The results below (Tble 2) indicted tht the normlized permete flows of ll of the membrne elements were significntly below mnufcturer s specifictions by 33%-66%; the til RO element from the UF-RO system hd the lowest normlized permete flow. The normlized slt rejection levels were slightly below mnufcturer s specifictions (by 0.2%-0.7%). The differentil pressure drop levels were in the norml rnge of 3-5 psid, indicting tht there ws no significnt blockge of the RO retentte chnnels. Tble 2. Results of RO membrne element performnce testing Element System Permete Flow, gpm 6 Slt Rejection, % Led SN UF-RO Til SN UF-RO Led, SN MBR-RO Til, SN MBR-RO Mnufcturer s Specifictions Differentil Pressure Drop, psid Internl visul exmintion The membrne elements were dissected nd unrolled. Direct visul exmintion (Figs. 4-5) reveled tht exposed RO membrne surfces hd brown stins tht were indictive of thin membrne fouling lyers. The brown stins were drker on the til RO elements, especilly the tested element from the UF-RO system (Fig. 4). Feed spcers Feed spcers re plstic net mteril (Vexr) designed to seprte membrne leves to form thin chnnel for feed flow. Feed spcers in ll of the membrne elements were clen without visul trces of foreign mteril. Permete spcers Permete spcers re typiclly mde of Tricot mteril nd provide porous chnnel for permete flow into centrl permete collection tube. Dmge of tricot mteril cn increse permete-side pressure losses. Tricot mteril ws found to be in good condition in ll membrne elements. Glue lines For ll of the membrne elements, the glue lines t the edges of membrne leves, which seprted feed nd permete chnnels, were in good condition nd showed no signs of pouching or delmintion. D-7

277 SN UF-RO System, Led RO Element SN UF-RO System, Til RO Element Figure 4. Internl view of the led nd til RO elements from the UF-RO system. 7 D-8

278 SN MBR-RO System, Led RO Element SN MBR-RO System, Til RO Element Figure 5. Internl view of the led nd til RO elements from the MBR-RO system. 8 D-9

279 Membrne coupon smpling nd storge For ech membrne element, membrne coupons were smpled from severl loctions s indicted in the exmple shown in Fig. 6. The membrnes were stored in seled plstic bgs nd kept refrigerted before subsequent testing. Figure 6. Exmple loctions of membrne coupon smpling Opticl Imging The surfces of membrne smples tken ner the fluid entrnce (front), midsection (middle), nd exit (rer) regions of ech membrne element (see Fig. 6) were imged opticlly. Color imges were tken under white LED lighting. High-contrst, gryscle imges were tken utilizing specil imging method in order to enhnce the contrst of difficult-to-see membrne surfce fetures. Opticl imges of membrne smples from the UF-RO systems re shown in Figs 7-8. Color imges revel membrne surfce discolortions, prticulrly the surfces of membrne smples tken from the til RO element (Fig. 7); these discolortions could be due to orgnic fouling. Towrd the rer end of the til RO element, trce level presence of powdery mteril ws pprent from high contrst imges (Fig. 8). For ll membrne smples tken from the UF-RO system, embossed ptterns resembling tht of the permete crrier mteril were pprent, suggesting the occurrence of membrne compction the deformtion of the membrne nd 9 D-10

280 membrne bcking mteril under pressure. Embossing of the membrne bcking into the permete (Tricot) crrier mteril cn result in incresed pressure losses on the permete side of the elements. UF-RO System Led RO Element SN UF-RO System Til RO Element SN Rer Middle Front Flow Direction Figure 7. Color surfce imges of membrne smples tken from vrious loctions in the led nd til RO membrne elements from the UF-RO system. 10 D-11

281 UF-RO System Led RO Element SN UF-RO System Til RO Element SN Rer Middle Front Flow Direction Figure 8. High-contrst surfce imges of membrne smples tken from vrious loctions in the led nd til RO membrne elements from the UF-RO system. Opticl imges of membrne smples from the MBR-RO systems re shown in Figs Membrne surfce discolortions were pprent nd were most pronounced on smples tken from the til RO element. High contrst imges lso reveled trce level of powdery mterils towrd the rer end of the til RO element (Fig. 10). Embossed ptterns on the surfces of the membrne smples suggest significnt occurrence of membrne compction (Fig. 10). 11 D-12

282 MBR-RO System Led RO Element SN MBR-RO System Til RO Element SN Rer Middle Front Flow Direction Figure 9. Color surfce imges of membrne smples tken from vrious loctions in the led nd til RO membrne elements from the MBR-RO system. 12 D-13

283 MBR-RO System Led RO Element SN MBR-RO System Til RO Element SN Rer Middle Front Flow Direction Figure 10. High-contrst surfce imges of membrne smples tken from vrious loctions in the led nd til RO membrne elements from the MBR-RO system Fujiwr test The Fujiwr test is qulittive test tht detects the presence of chemiclly bound hlogen compounds on the membrne surfce. The Fujiwr test results were positive for ll membrne smples, except for the smple tken from the til RO element of the UF-RO system. Hlogented membrne surfce is indictive of chemicl trnsformtion occurring t the membrne surfce due to exposure to chemicl oxidnts (e.g., free chlorine), which my ffect membrne slt-rejection performnce. It is noted tht polymide membrnes hve low tolernce 13 D-14

284 to free chlorine (bout 1000 ppm-h). Polymide membrnes tolernce to chlormine cn be significntly higher (bout 300,000 ppm-h); however, membrne exposure to chlormine my led to enhnced membrne hlogention in the presence of certin ions (e.g., Fe(II)) 2. Finlly, one should note tht positive Fujiwr test does not quntify the extent of membrne dmge, but merely suggests the occurrence of membrne surfce hlogention. Tble 3. Fujiwr test results. Element System Fujiwr Test Result Led (SN ) UF-RO Positive (+) Til (SN ) UF-RO Negtive (-) Led (SN ) MBR-RO Positive (+) Til (SN ) MBR-RO Positive (+) FTIR nlysis FTIR nlysis ws conducted using Perkin Elemer 1600 FT-IR system with HATR (ZnSe crystl) ttchment. FTIR nlysis (Fig ) showed peks ssocited with O-H, N-H, C=O, mides, C-O, C-N groups. These groups re consistent with the polymide ctive lyer of the RO membrnes. It is noted tht the C=O nd C-O stretches re lso expected if polyscchrides, orgnic proteins, nd crbohydrtes from orgnic foulnts re on the membrne surfce. Figure 11. FT-IR spectrl imge of membrne surfce smples from the UF-RO system. 2 C.J. Gbelich, J.C. Frnkin, F.W.Gerringer, K.P. Ishid, I.H. Suffet, Enhnced oxidtion of polymide membrnes using monochlormine nd ferrous iron, J. Membr. Sci. 258 (2005) D-15

285 There ppers to be noticeble difference between the FTIR spectr of membrne smples tken from the led nd the til RO elements of the UF-RO system (Fig. 11). Specificlly, IR peks for the til RO element membrne smples ppered to be pronounced, reltive to those of the led RO element membrne smples, t wvenumbers in the rnge of cm -1, while reduced t other wvenumber rnge. Given tht the membrne surfces of the til RO element membrne smples were most stined (Fig. 7), the pronounced IR peks my be indictive of orgnic fouling, possibly polyscchrides nd/or polyscchride-like substnces. However, FTIR nlysis lone is insufficient to provide definitive chemicl identifiction. Figure 12. FT-IR spectrl imge of membrne surfce smples from the MBR-RO system Light Microscope Anlysis nd Bcteri Grm Stining Test Foulnt smples were collected, stined, nd exmined with light microscope. Grm positive bcteri re stined blue while Grm negtive bcteri re stined red. For the UF-RO system, Grm Positive bcteri were visible for the led RO element membrne smple (Fig. 13). In the til RO element, the foulnt mteril ppered morphous; there ws no definitive indiction of bcteril presence in the til RO element membrne smples (Fig. 13b). 15 D-16

286 For the MBR-RO system, the imge of Fig. 14 indicted possible presence of fungi in the led RO element membrne smples. In the til RO element, foulnt mterils ppered morphous; there ws no definitive indiction of bcteril presence in the til RO element membrne smples (Fig. 14b). () (b) UF-RO System Led RO Element SN UF-RO System Til RO Element SN Fig. 13. Light microscope imge (1000X) of grm-stined foulnt smples from the () led nd (b) til RO elements of the MBR-RO system. () (b) MBR-RO System Led RO Element SN MBR-RO System Til RO Element SN Fig. 14. Light microscope imge (1000X) of grm-stined foulnt smples from the () led nd (b) til RO elements of the MBR-RO system. 16 D-17

287 SEM-EDS nlysis SEM/EDS nlysis ws conducted using Philips XL30 FEG Field Emission Microscope with n EDAX ttchment for elementl nlysis vi energy dispersive X-ry spectroscopy (EDS). SEM imges of the membrne smples re shown in Figs for membrne smples from the UF- RO system nd in Figs for membrne smples from the MBR-RO system. SEM imges suggest thin foulnt lyer on the membrne surfces (Fig. 15 nd Fig. 18), s well s some powdery mterils (Figs ). EDS nlysis suggest tht inorgnic foulnt constituents were primrily silicon, iron, nd clcium. Sulfur lso ppered s mjor constituent, but my lso originte from the sulfur content of the RO membrne polysulfone support lyer. At the level of EDS sensitivity, it is likely tht the detected crbon nd oxygen were due to interferences from the RO membrne (i.e., polymide ctive lyer on top of polysulfone nd polyester bcking). UF-RO: Led RO SN Figure 15. SEM imge nd EDS micronlysis of membrne surfce from the led RO element membrne smples of the UF-RO system. UF-RO: Til RO SN Figure 16. SEM imge nd EDS micronlysis of membrne surfce from the til RO element membrne smples of the UF-RO system. 17 D-18

288 MBR-RO: Led RO SN Figure 17. SEM imge nd EDS micronlysis of membrne surfce from the led RO element membrne smples of the MBR-RO system. MBR-RO:Til RO SN Figure 18. SEM imge nd EDS micronlysis of membrne surfce from the til RO element membrne smples of the MBR-RO system Membrne smple coupons performnce Membrne performnce (wter permebility nd slt trnsport coefficient) using membrne smple coupons from the RO elements ws evluted using dechlorinted tp wter (~1000 S), before nd fter membrne clening. Clening of membrne smple coupons were conducted for initil ssessments of membrne clening fesibility. Membrne clening involved sequence of low ph ( ) nd high ph clening ( ) for 60 minutes in ech step. 18 D-19

289 Except for the smple from the UF-RO system led RO element, wter permebility for ll membrne smples prior to clening were well below mnufcturer s specifictions (by 43% for the til element smple from the UF-RO system nd 19-31% for the smples from the MBR-RO system). Slt trnsport coefficient vlues prior to clening were either slightly below (UF-RO system til element), within (MBR-RO led element), or bove specifictions (UF-RO led element nd MBR-RO til element). Upon membrne clening, wter permebility ws recovered for ll membrne smple coupons to within or bove mnufcturer s specifictions. Slt trnsport coefficient vlues, however, were elevted significntly bove the mnufcturer specifictions fter membrne clening (by up to % for the smples from the UF-RO system nd % for the smples from the MBR-RO system). Elevted slt trnsport coefficient my suggest tht dmged res of the membrnes were exposed once the foulnt lyer ws removed by clening. Tble 4. Performnce of membrne smple coupons before nd fter membrne clening. Source of Membrne Smple Wter Permebility Slt Trnsport Coeff. (10-8 m/s/kp) (10-8 m/s) UF-RO System: Led RO Element Pre-Clen SN Post-Clen UF-RO System: Til RO Element Pre-Clen SN Post-Clen MBR-RO System: Led RO Element Pre-Clen SN Post-Clen MBR-RO System: Til RO Element Pre-Clen SN Post-Clen Mnufcturer's specifictions In compring the results of membrne smple coupon testing with membrne element testing (Section 2.1.2), one should note tht membrne smple coupon testing is more sensitive test for quntifying membrne sheet performnce. The results of membrne smple coupon testing only represents membrne performnce in specific sections of the membrne element (see Fig. 6). However, membrne smple coupon testing excludes the impct of flow chnnel integrity of the membrne element, s well s the effect of flow chnnel spcers. Therefore, testing of smll membrne re (from membrne smple coupons) should not be tken s representtive of the whole membrne element test. Tests with smll sections of the membrne serve s indictors of potentil performnce problems tht my develop over time nd thus re useful for evlution nd optimiztion of process conditions. 19 D-20

290 Other tests The following tests could not be conducted due to insufficient foulnt mteril on the surfces of the membrne smples: () Loss on ignition, nd (b) Ion nlysis on digested smple coupons Membrne Scling Tendency Membrne utopsy results, s described in Section 2.1, indicted the presence of orgnic fouling, s well s some inorgnic constituents (silicon, iron, clcium, nd possibly sulfur). In order to evlute the relevnce of the membrne utopsy results, wter qulity dt of the pilot RO systems feed strems (obtined from LACSD; Tble A1) were employed to ssess the membrne scling tendency. Typiclly, membrne scling tendency (for the mjority of springly soluble minerl slts) is ssessed in terms of thermodynmic sturtion index, SI x IAP/ K, where IAP is the ion sp, x ctivity product nd K sp,x is the solubility product for minerl slt x. If the strem in the RO retentte fluid chnnel is supersturted with respect to one or more minerl sclnts (i.e., SI x >1), minerl scle my form nd block RO membrne surfces, which would led to permete flux decline nd eventully shortening of membrne useful life. In the present nlysis, RO concentrte sturtion indices were estimted bsed on the verge, minimum, nd mximum concentrtion levels of ionic species in the feed UF filtrte nd MBR permete of the UF-RO nd MBR-RO systems (Tble A1; see Appendix A), multiplied by the ion concentrtion fctor (CF) of the RO concentrte strems (CF=6.39 t RO recovery level of 85% nd nominl slt rejection of 97%). For the purpose of these clcultions, ph levels in the RO concentrte were estimted to be t ph ~7.5. Dissolved sulfide (HS - ) concentrtion in the RO feed strems, per informtion provided by LACSD, ws estimted to be t the limit of detection. (0.1 mg/l). One should note tht membrne scling tendency ssessment bsed on SI x does not tke into ccount the kinetics of scle formtion. In other words, supersturtion (SI x >1) is necessry but not sufficient condition for scle formtion. Antisclnt tretment, for exmple, cn effectively retrd minerl scle formtion (by ffecting the kinetics of crystl nucletion nd growth), thereby llowing the RO process to operte under supersturted conditions (SI x >1). Antisclnt tretment, however, is only effective up to limited supersturtion levels (SI x ), depending on the minerl sclnt type, ntisclnt type nd dose, nd RO operting conditions. The clcultion results (Tbles 5-6) confirmed tht the RO concentrte strems of the UF-RO nd MBR-RO systems were supersturted (SI x >1) with respect SiO 2, Fe(OH) 3, FeS, consistent with the results of EDS micronlysis which indicted the presence of silicon, iron, nd sulfur on the surfces of the membrne smples (Figs ). The presence of trce clcium on the surfces of the membrne smples (Figs ) my be due to CCO 3, consistent with the slight supersturtion of the RO concentrte strems with respect to CCO 3 (Tbles 5-6). The presence of sulfur (Figs ) would be unlikely to originte from gypsum scling (CSO 4 2H 2 O; Tbles 5-6) s the RO concentrte ws consistently below sturtion with respect to gypsum. 20 D-21

291 Tble 5. Minerl slt sturtion indices of RO concentrte, estimted bsed on wter qulity dt of UF filtrte in the pilot UF-RO system (Tble A1). RO Concentrte ph ws estimted t 7.5. Ion concentrtion level Averge Minimum Mximum Minerl Slt Sturtion Index () Fe(OH) FeS (b) CCO BSO CF SiO C 3 (PO4) Al(OH) CSO 4 2H 2 O () when dissolved iron is primrily in the form of Fe +3. (b) when dissolved iron is primrily in the form of Fe +2 nd RO feed dissolved sulfide concentrtion is t the detection limit of 0.1 mg/l. Tble 6. Minerl slt sturtion indices of RO concentrte, estimted bsed on wter qulity dt of MBR permete in the MBR-RO system (Tble A1). RO Concentrte ph ws estimted t 7.5. Ion concentrtion level Averge Minimum Mximum Minerl Slt Sturtion Index () Fe(OH) FeS (b) CCO BSO CF SiO C 3 (PO4) Al(OH) CSO 4 2H 2 O () when dissolved iron is primrily in the form of Fe +3. (b) when dissolved iron is primrily in the form of Fe +2 nd RO feed dissolved sulfide concentrtion is t the detection limit of 0.1 mg/l. 21 D-22

292 3. Conclusions ) Exmintions of the submitted RO membrne elements did not revel visully-observble evidence of physicl dmge (e.g., glue line filure or delmintion). b) Lower thn norml membrne productivities were evident bsed on performnce testing of full RO elements nd membrne smple coupons. For the UF-RO system, the til RO element hd 50% lower productivity thn the led element. For the MBR-RO system, the led element hd slightly lower (17%) productivity thn the til element. Performnce of the RO membrne elements ws well below mnufcturer specifictions (for ll elements) by 33% or more, prticulrly the til RO element of the UF-RO system (66% below specifictions). Wter permebilities were mostly below mnufcturer s specifictions, with the membrne smple coupon from the UF-RO system til RO element hving the lowest wter permebility (43% below mnufcturer specifictions). c) Internl visul exmintions, opticl imging, light microscope nlysis, FTIR nlysis, nd SEM-EDS nlysis of the membrne surfces indicted the presence of thin lyer of brown foulnt mterils on the membrne surfces of ll membrne elements, with the til RO element from the UF-RO system ppering to be most fouled. The foulnt lyers ppered to be composed of both orgnic nd inorgnic mterils (with silicon, clcium, iron, nd possibly sulfur s primry inorgnic constituents). Biologicl exmintion reveled trce grm-positive bcteri in the led RO element of the UF-RO system nd possible fungi in the led RO element of the MBR-RO system. d) Results of performnce testing of membrne elements nd membrne smple coupons reveled lower thn norml levels of slt rejection (0.2%-0.7% below the RO element mnufcturer s specifiction). Fujiwr test ws positive for the presence of hlogen (i.e., chlorine) on the membrnes smples from ll of the RO membrne elements, except for those tken from the UF-RO system til RO element. e) Preliminry ssessment of membrne clening suggest tht foulnt mterils cn be removed to recover RO membrne permebility to within or bove mnufcturer s specifictions. However, clening resulted in elevtion of the slt pssge (i.e., slt trnsport coefficient) by up to % nd % bove mnufcturer specifictions for the membrne smples from the UF-RO nd MBR-RO systems, respectively, suggesting tht hlogented membrne res were exposed upon removl of foulnt mterils. 22 D-23

293 4. Appendix 4.1. Wter qulity dt Tble A1. Wter qulity dt of UF filtrte nd MBR permete (i.e., RO feed strems) from LACSD UF-RO nd MBR-RO pilot systems, respectively. UF Filtrte MBR Permete Prmeter Unit Avg. Min Mx Avg. Min Mx Field ph Turbidity NTU -- < < TSS mg/l <2.5 <3.0 COD mg/l Sol COD mg/l TOC mg/l NH 3 mg N/L < TKN mg N/L < NO 3 mg N/L -- <0.1 < NO 2 mg N/L -- < < o-po4 mg P/L -- < < Clcium mg/l Mgnesium mg/l Sodium mg/l Potssium mg/l mg/l Totl Alklinity CCO Sulfte mg/l Chloride mg/l TDS mg/l Brium μg/l Strontium μg/l Fluoride mg/l Iron mg/l Aluminum μg/l -- < < Boron mg/l SiO 2 mg/l Diss. Sulfide mg/l <0.1 <0.1 <0.1 <0.1 <0.1 < D-24

294 Membrne Autopsy Report Prepred for: Snittion Districts of Los Angeles County August 15, 2012 Envirosoft Corportion 2288 Westwood Blvd. Suite 200 Los Angeles, CA Tel.: 1 (310) Emil: info@envirosoft.net Web: D-25

295 Synopsis Los Angeles County Snittion Districts (LACSD) provided four sets of Hydrnutics ESPA (Low Pressure RO) membrne elements to Envirosoft for nlysis. Two of the elements were the led (SN ) nd til (SN ) RO elements from LACSD pilot UF-RO system, while the remining two were the led (SN ) nd til (SN ) RO elements from LACSD pilot MBR-RO system. Exmintions of the submitted RO membrne elements reveled no visully-observble evidence of physicl dmge. Fiberglss wrps, end cps, brine sels, nd permete tubes ppered to be in good condition. Feed nd permete spcers nd glue lines were lso in stisfctory mechnicl condition. Performnce testing of full RO elements nd membrne smple coupons reveled lower thn norml membrne productivities. The productivities of the led RO elements from the UF- RO nd MBR-RO systems were slightly lower thn norml by 8% nd 15%, respectively. However, performnce testing of the led element membrne smple coupons reveled norml wter productivity level, suggesting tht fouling in the led elements were loclized nd in its erly stge. Til element productivities were significntly below norml for both the UF-RO (by 41%) nd MBR-RO (by 25%) systems. The lower-thn-norml performnce levels of the til elements were consistent with results from smple coupon performnce testing, with the UF-RO til element hving the lowest level of productivity. Performnce testing lso reveled norml or ner norml levels of slt rejection (i.e., within 0.1% of expected norml performnce). Fujiwr test ws positive for the presence of hlogen (i.e., chlorine) only for the membrnes smples from the MBR-RO system. Internl visul exmintions, opticl imging, light microscope nlysis, FTIR nlysis, nd SEM-EDS, CEI nlysis of the membrne surfces indicted the presence of brownish foulnt mterils on the membrne surfces of ll membrne elements, with the til RO element from the UF-RO system ppering to be most fouled. The foulnt lyers ppered to be composed primrily of metl silictes (clcium silictes), cly, nd iron-bering grnulr mteril, s well s grm negtive bcteri nd morphous orgnic mteril. Preliminry ssessments of membrne clening suggest tht the foulnt mterils cn be removed to recover RO membrne permebility to within mnufcturer s specifictions. Clening resulted in slight elevtion of the slt pssge (i.e., slt trnsport coefficient) tht remined within mnufcturer specifictions. The bove utopsy results suggest tht there is merit in exploring process performnce improvements in order to mitigte fouling by metl silictes, iron-bering mteril, nd orgnics, s well s in hving periodic testing of UF/MBR membrne integrity. 1 D-26

296 Contents Synopsis... 1 Contents Work Sttement Summry of Results & Anlysis Membrne Autopsy Results Externl visul exmintion Membrne element performnce Internl Visul Exmintion Membrne coupon smpling nd storge Fujiwr test Acid testing FTIR nlysis Light Microscope Anlysis nd Bcteri Grm Stining Test SEM-EDS nlysis CEI nlysis Membrne smple coupons performnce Other tests Conclusions D-27

297 1. Work Sttement Los Angeles County Snittion Districts (LACSD) nd Metropolitn Wter District of Southern Cliforni (MWDSC) hve been evluting dvnced tretment of the effluent from the Joint Wter Pollution Control Plnt (JWPCP). Two different tretment processes were pilot tested in prllel, utilizing n UF-RO pilot system (UF: 0.04 m, PVDF, Memcor, Siemens) nd n MBR- RO pilot system (MBR: 0.04 m, PVDF, ZeeWeed 500C, GE). Ech pilot system employed n RO unit with totl of 21 RO membrne elements (Hydrnutics ESPA2-4040), rrnged in 2:1 rry configurtion with 7 elements per series per stge. In ech RO unit, ntisclnt tretment (King Lee PreTret Plus 0100) nd RO feedwter ph djustment (to ph ~6.5 with sulfuric cid) were employed to mitigte membrne minerl scling. Chloromine residul (3-4 ppm) ws mintined in the RO feed strems in order to control biofouling. Ech RO unit ws operted t trget wter recovery level of 85%. Envirosoft ws retined by LACSD to ssess (vi membrne utopsy) the performnce of four RO elements from the pilot systems. Both the MF-RO nd the MBR-RO pilot systems were shut down on June 21, Two representtive RO membrne elements ( led element from the 1st RO unit stge nd the til element from the 2nd RO unit stge) from ech pilot system were removed nd provided to Envirosoft. This report summrizes the membrne utopsy results. 3 D-28

298 2. Summry of Results & Anlysis 2.1. Membrne Autopsy Results The pilot UF-RO nd MBR-RO systems were shut down in the morning of June 21, From the RO unit of ech system, led RO membrne element in the 1 st RO unit stge nd the til membrne element in the 2 nd RO unit stge were removed from the RO pressure vessels nd submitted for utopsy. The RO elements were ll Hydrnutics ESPA (Size: 4 x 40 ). Tble 1. Submitted RO membrne elements. No System RO Element Position Seril No. (SN) 1 UF-RO Led UF-RO Til MBR-RO Led MBR-RO Til Externl visul exmintion Element weight The RO elements were weighed prior to utopsy given tht RO element weight is often indictive of the degree of fouling. The led (SN ) nd til (SN ) RO elements from the UF-RO system weighed 8 lbs ech. The led (SN ) nd til (SN ) RO elements from the MBR-RO system weighed 9 lbs ech. New RO elements of this type typiclly weigh 7-9 lbs. Fiberglss wrp The fiberglss wrpping protects the element from externl differentil pressure, provides compressive strength to prevent telescoping nd to ensure tht the vrious membrne components re held in their correct position for optimum performnce. Dmge to the fiberglss wrp cn be n indiction of rough hndling or dmge from excessive differentil pressure cross the membrne surfce. The outer fiberglss csing of the membrne elements ppered to be in good condition, with no pprent visible signs of physicl dmge (Fig. 1). Brine sel The brine sels were in good condition nd showed no visible signs of physicl dmge tht could llow bypss of the NF/RO concentrte wter round the spirl wound membrne scrolls (Figs. 1-3). End-cps / Anti-telescoping device (ATD) ATDs re designed to prevent telescoping of element leves t norml differentil pressures. There ws no visible sign of physicl dmge (Figs. 2-3). Permete tube There ws no visible sign of physicl dmge on the ends of the permete tubes tht could llow by-pss of feed wter (Figs. 2-3). 4 D-29

299 UF-RO Led Element UF-RO Til Element MBR-RO Led Element MBR-RO Til Element Figure 1. Photogrph of submitted RO membrne elements. UF-RO Led: Feed Entry UF-RO Led: Concentrte Exit UF-RO Til: Feed Entry UF-RO Til: Concentrte Exit Figure 2. Photogrphs of the front (feed entry) nd rer (concentrte exit) ends of the led nd til RO elements from the UF-RO system. 5 D-30

300 MBR-RO Led: Feed Entry MBR-RO Led: Concentrte Exit MBR-RO Til: Feed Entry MBR-RO Til: Concentrte Exit Figure 3. Photogrphs of the front (feed entry) nd rer (concentrte exit) ends of the led nd til RO elements from the MBR-RO system Membrne element performnce The performnce the RO elements ws tested t 15% wter recovery nd net driving pressure of 131 psig, employing de-chlorinted city wter (~1000 S). The normlized permete flow nd slt rejection of the membrne element represents the overll (verge) performnce of the entire membrne element, including the membrne sheets, the effect of chnnel spcers, s well s the integrity of internl element flow connections nd fluid chnnels. The results below (Tble 2) indicted tht the normlized permete flows of the led RO elements from both the UF-RO nd MBR-RO systems were below mnufcturer s specifictions by 8%-15%. The til RO elements from both systems were significntly below mnufcturer s specifictions by 25-41%. The til RO elements from the UF-RO system hd the lowest normlized permete flow. Normlized slt rejection levels were ll within mnufcturer specifictions except for the til RO element from the UF-RO system, which ws just slightly below mnufcturer s specifictions (by 0.1%). The differentil pressure drop levels were in the norml rnge of 3-5 psid, indicting tht there ws no significnt blockge of the RO retentte chnnels. 6 D-31

301 Tble 2. Results of RO membrne element performnce testing Element System Permete Flow, gpm Slt Rejection, % Differentil Pressure Drop, psid Led (SN ) UF-RO Til (SN ) UF-RO Led (SN ) MBR-RO Til (SN ) MBR-RO Mnufcturer s Specifictions Internl Visul Exmintion Scroll end exmintion ATD were removed for exmintion of the scroll ends of the membrne leves for the presences of fouling, feed spcer extrusion, nd membrne gpping. Ech scroll end ws lso exmined for signs of membrne telescoping dmge. The scroll ends of the led RO element from the UF-RO systems were reltively free from debris, lthough cler ornge stin ws pprent (Fig.4). The scroll ends for the other three elements were stined with n ornge colored foulnt mteril (Figs. 4, 8, 12, 16) tht resembled cly. In ech of these elements, the foulnt mteril ws concentrted round the res surrounding the permete tube, possibly trpped by the ATD. Internl visul exmintion The membrne elements were dissected nd unrolled. Direct visul exmintion (Figs. 4-5) reveled tht exposed RO membrne surfces hd brown stins tht were indictive of thin membrne fouling lyers (Figs. 5-6, 9-10, 13-14, 17-18). The brown stins were drker on the til RO elements from the UF-RO (Fig. 9-10) nd MBR-RO systems (Fig ). Feed spcers Feed spcers re plstic net mteril (Vexr) designed to seprte membrne leves to form thin chnnel for feed flow. Feed spcers in ll of the membrne elements ppered to be without significnt visul trces of foreign mteril (Figs. 7, 11, 15, 19). Permete spcers Permete spcers re typiclly mde of Tricot mteril nd provide porous chnnel for permete flow into centrl permete collection tube. Dmge of tricot mteril cn increse permete-side pressure losses. Tricot mteril ws found to be in good condition in ll membrne elements. Glue lines For ll of the membrne elements, the glue lines t the edges of membrne leves, which seprted feed nd permete chnnels, were in good condition nd showed no signs of pouching or delmintion. 7 D-32

302 UF-RO Led: Feed Entry UF-RO Led: Concentrte Exit Figure 4. Photogrphs of the front (feed entry) nd rer (concentrte exit) ends of the led RO element from the UF-RO system. Figure 5. Photogrph of the membrne surfce of the led RO element from the UF-RO system. 8 D-33

303 Figure 6. Photogrph of the membrne surfce of the led RO element from the UF-RO system. Figure 7. Imge of the feed spcer of the led RO element from the UF-RO system. 9 D-34

304 UF-RO Til: Feed Entry UF-RO Til: Concentrte Exit Figure 8. Photogrphs of the front (feed entry) nd rer (concentrte exit) ends of the til RO element from the UF-RO system. Figure 9. Photogrph of the membrne surfce of the til RO element from the UF-RO system. 10 D-35

305 Figure 10. Photogrph of the membrne surfce of the til RO element from the UF-RO system. Figure 11. Imge of the feed spcer of the til RO element from the UF-RO system. 11 D-36

306 MBR-RO Led: Feed Entry MBR-RO Led: Concentrte Exit Figure 12. Photogrphs of the front (feed entry) nd rer (concentrte exit) ends of the led RO element from the MBR-RO system. Figure 13. Photogrph of the membrne surfce of the led RO element from the MBR-RO system. 12 D-37

307 Figure 14. Photogrph of the membrne surfce of the led RO element from the MBR-RO system. Figure 15. Imge of the feed spcer of the led RO element from the MBR-RO system. 13 D-38

308 MBR-RO Til: Feed Entry MBR-RO Til: Concentrte Exit Figure 16. Photogrphs of the front (feed entry) nd rer (concentrte exit) ends of the til RO element from the MBR-RO system. Figure 17. Photogrph of the membrne surfce of the til RO element from the MBR-RO system. 14 D-39

309 Figure 18. Photogrph of the membrne surfce of the til RO element from the MBR-RO system. Figure 19. Imge of the feed spcer of the til RO element from the MBR-RO system 15 D-40

310 Membrne coupon smpling nd storge For ech membrne element, membrne coupons were smpled t the midsection of the membrne element. The membrnes were stored in seled plstic bgs nd kept refrigerted before subsequent testing described in Sections Fujiwr test The Fujiwr test is qulittive test tht detects the presence of chemiclly bound hlogen compounds on the membrne surfce. The Fujiwr test results were negtive for membrne smples tken from the led nd til RO elements of the UF-RO system, but were positive for membrne smples tken from the led nd til RO elements of the MBR-RO system. Hlogented membrne surfce is indictive of chemicl trnsformtion occurring t the membrne surfce due to exposure to chemicl oxidnts, which my ffect membrne sltrejection performnce. One should note tht positive Fujiwr test does not quntify the extent of membrne dmge, but merely suggests the occurrence of membrne surfce hlogention. Tble 3. Fujiwr test results. Element System Fujiwr Test Result Led (SN ) UF-RO Negtive (-) Til (SN ) UF-RO Negtive (-) Led (SN ) MBR-RO Positive (+) Til (SN ) MBR-RO Positive (+) Acid testing Severl drops of dilute hydrochloric cid were plced on the fouled res of ll membrne smples. No bubbling ws visully detected indicting tht miniml presence of fouling by crbontes in ll of the smples tested FTIR nlysis FTIR nlysis ws conducted using Perkin Elmer 1600 FT-IR system with HATR (ZnSe crystl) ttchment. FTIR nlysis (Figs ) showed peks tht indicted C-H, C-N, N-H, C- C, C=C, N-H-C=O, nd N-C=O peks for ll membrne smples. These groups re consistent with the polymide ctive lyer of the RO membrnes. It is noted tht wek H-C-OH peks (Figs ) were lso pprent for ll membrne smples, which would be expected if polyscchrides, orgnic proteins, nd crbohydrtes from orgnic foulnts were on the membrne surfces. 16 D-41

311 Figure 20. FT-IR spectrl imge of membrne surfce smples from the led RO element of the UF-RO system. 17 D-42

312 Figure 21. FT-IR spectrl imge of membrne surfce smples from the til RO element of the UF-RO system. 18 D-43

313 Figure 22. FT-IR spectrl imge of membrne surfce smples from the led RO element of the MBR-RO system. 19 D-44

314 Figure 23. FT-IR spectrl imge of membrne surfce smples from the til RO element of the MBR-RO system. 20 D-45

315 Light Microscope Anlysis nd Bcteri Grm Stining Test Foulnt smples were collected, stined, nd exmined with light microscope. Grm positive bcteri re stined blue while Grm negtive bcteri re stined red. Grm negtive bcteri were visible for ll the membrne smples tested (Figs ) nd most pprent in the til element of the MBR-RO system (Fig. 25b). There were some indictions of grm positive bcteri in the til element of the UF-RO system (Figs. 24b). Amorphous orgnic mteril nd fungi were lso observed, prticulrly in the led element of the UF-RO system (Fig. 24). UF-RO Led Element UF-RO Til Element Fig. 24. Light microscope imge (1000X) of grm-stined foulnt smples from the () led nd (b) til RO elements of the UF-RO system. 21 D-46

316 MBR-RO Led Element MBR-RO Til Element Fig. 25. Light microscope imges (1000X) of grm-stined foulnt smples from the () led nd (b) til RO elements of the MBR-RO system SEM-EDS nlysis SEM/EDS nlysis ws conducted using Philips XL30 FEG Field Emission Microscope with n EDAX ttchment for elementl nlysis vi energy dispersive X-ry spectroscopy (EDS). SEM imges of the membrne smples nd the ssocited EDS results re shown in Figs for membrne smples from the UF-RO system nd in Figs for membrne smples from the MBR-RO system. SEM imges of the led nd til element membrne smples from the UF-RO system indicte grnulr foulnt mterils on the membrne surfces (Fig ). The extent of fouling ppered to be more significnt on the surfce of membrne smple from the til element (Fig. 27) thn tht of the led element (Fig. 26). EDS detected silicon, iron, clcium on both the led nd til element membrne smples (Figs ), suggesting fouling by metl silictes (e.g., 22 D-47

317 clcium silictes) nd iron-bering mterils. Aluminum nd phosphorus ws lso detected in the led element membrne smple (Fig. 26). Fine grnulr foulnt mterils were observed on the surfces of the membrne smples from the MBR-RO system, with the til element smple (Fig. 29) ppered to be more fouled thn the led element (Fig. 28). EDS nlysis (Fig. 28) of the led element smple indicted tht the foulnt mterils were composed of primrily clcium, luminum, nd iron. The til element smple (Fig. 29) ws composed of primrily iron, clcium, luminum, nd silicon, suggesting fouling by metl silictes (e.g., cly, clcium silictes) nd iron-bering mteril. Trce mounts of phosphorus nd iodine were lso detected in the til element membrne smple (Fig. 29). It is noted tht sulfur lso ppered s mjor constituent in the EDS nlysis of the bove membrne smples, which could hve originted from the sulfur content of the RO membrne polysulfone support lyer. At the level of EDS sensitivity, it is likely tht the detected crbon nd oxygen were due to interferences from the RO membrne (i.e., polymide ctive lyer on top of polysulfone nd polyester bcking). Figure 26. SEM imge nd EDS micronlysis of membrne surfce from the led RO element membrne smples of the UF-RO system. 23 D-48

318 Figure 27. SEM imge nd EDS micronlysis of membrne surfce from the til RO element membrne smples of the UF-RO system. Figure 28. SEM imge nd EDS micronlysis of membrne surfce from the led RO element membrne smples of the MBR-RO system. 24 D-49

319 Figure 29. SEM imge nd EDS micronlysis of membrne surfce from the til RO element membrne smples of the MBR-RO system CEI nlysis Chromtic Elementl Imging (CEI) ws employed to resolve the sptil distribution of inorgnic elements on fouled res of the membrne smples. The color nd color intensity in CEI imge cn revel the loction nd concentrtion levels of vrious elements on the fouled res of the membrne surfce. For membrne smples tken from the UF-RO system, CEI indicted tht the foulnt mterils on the led nd til RO elements were primrily composed of metl silictes nd iron-bering mteril. The ptches of foulnt mteril found on the led element (Fig. 26) were likely to be cly (clcium luminum silictes), long with trces of orgnic mteril (phosphorous nd crbon) (Fig. 30). The grnulr foulnt mteril on the til element (Fig. 27) ws composed minly of clcium silictes nd iron-bering mteril (Fig. 31). For the MBR-RO system, CEI of the surfce foulnt mteril on the led element smple reveled heterogeneous mixture of clcium, luminum nd iron, with trces of orgnic mteril (crbon) (Fig. 32). The til element smple ppered to be covered by cly (clcium luminum silicte) nd iron foulnt lyers, s well s orgnic mteril (crbon nd phosphorus) (Fig. 33). 25 D-50

320 Figure 30. CEI imge of membrne surfce from the led RO element membrne smples of the UF-RO system. Figure 31. CEI imge of membrne surfce from the til RO element membrne smples of the UF-RO system. 26 D-51

321 Figure 32. CEI imge of membrne surfce from the led RO element membrne smples of the MBR-RO system. Figure 33. CEI imge of membrne surfce from the til RO element membrne smples of the MBR-RO system. 27 D-52

322 Membrne smple coupons performnce Membrne performnce (wter permebility nd slt trnsport coefficient), bsed on membrne smple coupons from the RO elements, ws evluted using dechlorinted tp wter (~1000 S), before nd fter membrne clening. Clening of membrne smple coupons were conducted for initil ssessments of membrne clening fesibility. Membrne clening ws done using low ph membrne clener (ph ) contining EDTA t elevted temperture (35-40 o C) for ~2 hours. The results of membrne smple performnce testing re listed in Tble 2. Wter permebility for the led element membrne smples from both the UF-RO nd MBR-RO systems were within mnufcturer s specifictions. The slt trnsport coefficient (i.e., slt pssge) ws norml for the led element membrne smple of the UF-RO system, but ws slightly below norml (by 17%) for the led element smple of the MBR-RO system. The lowerthn-norml slt trnsport coefficient indicted tht the membrne slt rejection ws higher thn specified by the mnufcturer. Given tht membrne performnce (permebility nd slt trnsport) ws still stisfctory, clening ws not necessry for the led element membrne smples. Wter permebility for the til element membrne smples from both the UF-RO nd MBR-RO systems were lower thn norml by 24% nd 12%, respectively. Slt trnsport coefficient for the MBR-RO til element ws norml, while the slt trnsport coefficient of the UF-RO til element smple ws 29% below norml. Upon membrne clening, wter permebility vlues of the til element membrne smples from both systems were recovered to within norml rnge. It is noted tht foulnt removl due to clening ws visully observble for both smples (Fig ). Post-clening slt trnsport coefficient of the UF-RO til element smple ws bove the preclening vlues, but within mnufcturer specifiction for the MBR-RO til element smple nd somewht below (by 13%) the lower expected vlue for the UF-RO til element smple (Tble 4). Tble 4. Performnce of membrne smple coupons before nd fter membrne clening. Source of Membrne Smple Wter Permebility Slt Trnsport Coeff. (10-8 m/s/kp) (10-8 m/s) UF-RO System: Led RO Element Pre-Clen SN Post-Clen - - UF-RO System: Til RO Element Pre-Clen SN Post-Clen MBR-RO System: Led RO Element Pre-Clen SN Post-Clen - - MBR-RO System: Til RO Element Pre-Clen SN Post-Clen Mnufcturer's specifictions D-53

323 In compring the results of membrne smple coupon testing with membrne element testing (Section 2.1.2), one should note tht membrne smple coupon testing is more sensitive test for quntifying membrne sheet performnce. The results of membrne smple coupon testing only represents membrne performnce in specific sections of the membrne element. However, membrne smple coupon testing excludes the impct of flow chnnel integrity of the membrne element, s well s the effect of flow chnnel spcers. Therefore, testing of smll membrne re (from membrne smple coupons) should not be tken s representtive of the whole membrne element test. Tests with smll sections of the membrne serve s indictors of potentil performnce problems tht my develop over time nd thus re useful for evlution nd optimiztion of process conditions. Pre-Clen Post-Clen Fig 34. Imges of membrne surfce before nd fter chemicl clening. Membrne smples were tken from the til RO element of the UF-RO system. 29 D-54

324 Pre-Clen Post-Clen Fig 35. Imges of membrne surfce before nd fter chemicl clening. Membrne smples were tken from the til RO element of the MBR-RO system Other tests The following tests could not be conducted due to insufficient foulnt mteril on the surfces of the membrne smples: ) Loss on ignition, nd b) ion nlysis on digested smple coupons. 30 D-55