TABLE OF CONTENTS. Wastewater Effluent Laboratory Results and Analytical Methods EEC Field Visits and Related Activities to Date...

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2 Trapzilla PerformanceEvaluation November15,2012 TABLEOFCONTENTS ES EXECUTIVESUMMARY...1 ES.1 Purpose...1 ES.2 ThirdPartyPerformanceEvaluation...1 ES.3 Conclusions...1 ES.4 SiteInformation...1 ES.5 ProductInformation...1 ES.6 FieldTestingData...2 ES.7 AcetobacterBacteriaCausingLowpHConditions...2 ES.8 ReducedDownstreamAccumulationwiththeTrapzilla...3 ES.9 Summary INTRODUCTION OBJECTIVES BACKGROUND FIELDACTIVITIES WastewaterSamplingMethods SAMPLINGRESULTS WastewaterQuality ClosedCircuitTelevisionObservations ScrapingSampling DyeTesting PumpingObservations CONCLUSIONS...15 Tables TableES1 Table41 Table51 WastewaterEffluentLaboratoryResultsandAnalyticalMethods...2 EECFieldVisitsandRelatedActivitiestoDate...6 WastewaterEffluentLaboratoryResultsandAnalyticalMethods...9 Figures Figure1 Figure21 Figure41 Figure51 Figure52 Figure53 Figure54 Figure55 Figure56 Figure57 Appendices (Appended)SiteLocationMap SiteLayout...5 EffluentSampleCollectionPoints...8 CCTVObservationsDownstreamoftheConcreteGreaseInterceptor...11 CCTVObservationsDownstreamoftheTrapzilla Unit...11 CCTVObservationsConductedbytheCityofBeaverton...12 AcetobacterXylinum...12 DyeTestingObservations...13 ConcreteGreaseInterceptorObservations...14 Trapzilla UnitAfterPumping...15 AppendixA AppendixB 25%RuleExample PhotosofSampleCollectionandMonitoring W MAThermaco,Inc. i EEC

3 Trapzilla PerformanceEvaluation November15,2012 ES ES.1 EXECUTIVESUMMARY Purpose ThepurposeofthisstudyistocomparetheeffluentperformanceoftheTrapzilla TZ600separatorto an existing 1,000gallon concrete grease interceptor at a highvolume retail doughnut bakery store operation.refertosection4.0,fieldactivities,ofthemainreportforadetaileddescriptionofmethods aswellasphotographicreferences. ES.2 ThirdPartyPerformanceEvaluation EnvironmentalEngineering&Contracting,Inc.wasretainedbyThermaco,Inc.toevaluateaTrapzilla TZ600 unit replacing a conventional 1,000gallon concrete grease interceptor at a highvolume retail doughnutbakerystoreoperationinbeaverton,oregon.thestudyobjectwastoevaluatethreefactors: Effluentquality Frequencyofmaintenance Assessmentofdownstreamsewermaterialaccumulation ES.3 Conclusions 1. No significant effluent sample difference was observed that contained fats, oils, and grease (FOG)withtheconcretegreaseinterceptorvs.theTrapzilla.Thetypeofdoughnutproduction process used at this facility generates low concentrations of FOG. Due to the low FOG concentrations in the collected effluent samples, a significant difference in FOGrelated performancebetweenthetwodesignscouldnotbeadequatelyevaluated. 2. Effluent ph improved from a high acidity ph of 3.69 to a mild acidity ph of 4.8 with the Trapzilla. 3. Effluent biological oxygen demand (BOD) concentrations were significantly lower with the Trapzilla (2,012 milligrams per liter [mg/l] with the Trapzilla vs. 6,674 mg/l without the Trapzilla ). 4. Effluenttotalsuspendedsolids(TSS)concentrationswerehigher(650mg/Lvs.387mg/L)with thetrapzilla. 5. LessdownstreammaterialaccumulationinthesewerlinewasobservedwiththeTrapzilla. 6. AcetobacterbacteriawerefoundtobethemostlikelycausalagentforlowpHconditions. ES.4 SiteInformation Thedoughnutbakerysiteisafranchiseoperationofanationallyrecognizedchain.Thefacility sexisting concretegreaseinterceptorwaseightyearsoldatthetimeofthestudy.theexistinggreaseinterceptor neededtobereplacedbecauseacidicwastewaterconditionshaddegradedtheconcrete.theconcrete grease interceptor was being pumped every two weeks. The Trapzilla unit was pumped every four weeks. ES.5 ProductInformation The existing concrete grease interceptor had a capacity of 1,000 gallons. The Trapzilla TZ600 has a capacity of 95 gallons. The Trapzilla uses a horizontal and vertical baffling arrangement to create W MAThermaco,Inc. 1 EEC

4 Trapzilla PerformanceEvaluation November15,2012 separation and retention within a smaller installation footprint. Trapzilla is constructed of polyethylene,amaterialthatwouldbetterwithstandtheacidicwastewaterobservedatthissiteand extendtheoperationallifeoftheunit. ES.6 FieldTestingData TheconcretegreaseinterceptorwasevaluatedduringathreemonthperiodfromDecember2011to latefebruary2012.attheendofthisevaluationperiod,theconcretegreaseinterceptorwasremoved and replaced with a Trapzilla TZ600 grease interceptor. The Trapzilla was evaluated for a three month period from March to early June See Section 4.0 of the main performance evaluation reportforadescriptionofsamplecollectionmethods. TableES1,WastewaterEffluentLaboratoryResultsandAnalyticalMethods Device Concrete Grease Interceptor Trapzilla ph SU TSS (mg/l) Parameter BOD 5 (mg/l) Oiland Grease (mg/l) Total Sulfide (ppm) Date SampleTime AnalyticalMethod SM4500 SM SM SM A H+B 25540D 5210B S2D 12/13/ , ND Beforepumping 12/14/ , ND Afterpumping 12/27/ ,400 ND ND Beforepumping 12/28/ ,400 5 ND Afterpumping 2/27/ ,080 ND Beforepumping Key:BOD 5 =biologicaloxygendemand ppm=partspermillion mg/l=milligramsperliter ND=nondetect ph=measureofacidityoralkalinity SU=standardunit 3/2/ , Afterdevice installation 3/29/ Beforepumping 3/30/ ,100 ND Afterpumping 4/30/ ,000 7 ND Beforepumping 5/1/ , ND Afterpumping 6/4/ ,100 1, ND BeforePumping 6/5/ ND AfterPumping SM=standardmethod SM4500H+B=StandardMethodforMeasuringpH SM25540D=StandardMethodforMeasuringTSS SM5210B=StandardMethodforMeasuringBOD SM 4500 S2D = Standard Method for Measuring Total Sulfide 1664A=StandardMethodforMeasuringOilandGrease TSS=totalsuspendedsolids TheTrapzilla unithadanaverageeffluentphof4.8versus3.69fortheconcretegreaseinterceptor. (ThisaverageexcludedtheJune5,2012,pHreading,whichwasconsideredanoutlier). The Trapzilla unit had lower average effluent BOD concentrations (2,012 mg/l) compared to the concretegreaseinterceptor(6,674mg/l). W MAThermaco,Inc. 2 EEC

5 Trapzilla PerformanceEvaluation November15,2012 TheTrapzilla unithadhigheraverageeffluenttssconcentrations(650mg/l)comparedtotheconcrete greaseinterceptor(387mg/l). TheeffluentFOGmeasuredinbothdeviceswaslowandtotalsulfidewasnondetectable.Thefacility s dischargedsolidspredominatelyconsistedofrawdoughandfrostingmaterials,whichcontainlittleoil andgrease. ES.7 AcetobacterBacteriaCausingLowPHConditions Thewhitish,clumpedmaterialfoundontheconcretegreaseinterceptorwetwallsurfaceswastestedby SustainableScientificSolutionsusingenzymaticmaterialsandwasdeterminedtobecellulosicmatter created by Acetobacter xylinum bacteria. The Acetobacter xylinum bacterium is common and is especiallyproficientatconvertingsugarsanddigestiblecarbohydratesintocelluloseandaceticacid.the productionofaceticacidcreatesalowphconditioninthewastewater.thecelluloseprovidesasuitable habitatforthebacteria,andtheaceticacidisbelievedtopreventotherbacteriatypesfromgrowing. FurtherresearchisneededtodeterminewhytheTrapzilla effluenthadnoticeablyreducedacidity.the followingarepossibleexplanationsfortheincreasedph: a. TheslickpolyethylenewallsoftheTrapzilla providedlesshabitatforbacterialcolonization. b. The shorter hydraulic residence time of the Trapzilla provided less opportunity for the Acetobacterbacteriatoproduceaceticacid. ES.8 ReducedDownstreamAccumulationwiththeTrapzilla Theclosedcircuittelevision(CCTV)videoofthedownstreamsewershowedlessmaterialaccumulation (potentiallyattributedtocellulosefromacetobacter)downstreamofthetrapzilla ascomparedtothe 1,000gallonconcretegreaseinterceptor.Thefactorsexplainedabovearebelievedtobethecauseof thedecreasedaccumulation.refertosection5.2,closedcircuittelevisionobservation,ofthereport forthecctvmethodsandphotographicreferences. ES.9 Summary While this site did not generate appreciable FOG, the Trapzilla achieved comparable separation efficiencycomparedtothe1,000gallonconcretegreaseinterceptor.theeffluentphimprovedby1.11 units(asignificantreductioninacidity).theeffluentbodconcentrationswerereducedby70%,while theeffluenttssconcentrationswereincreasedby67%.thedownstreamsewerdepositswerevisibly reducedwiththetrapzilla versusthe1,000gallongreaseinterceptor. Further evaluation is required to determine if the low ph, high TSS, and downstream material accumulationisduetotheconversionofsugarsandcarbohydratesbyacetobacterbacteria.duetoits acidresistant polyethylene construction, the Trapzilla separator is expected to have a longer operationallifetimethanthereplacedconcretegreaseinterceptor. W MAThermaco,Inc. 3 EEC

6 Trapzilla PerformanceEvaluation November15, INTRODUCTION EnvironmentalEngineering&Contracting,Inc.(EEC) 1 isaconsultingandengineeringfirmthatsupports municipalwastepretreatmentandcollectionsystemprojects.eecroutinelyconductsstudiesforpublic andprivateentitiesthroughoutcaliforniaandtheunitedstates. EECpreparedthisreporttodocumenttheresultsofafieldperformanceevaluationoftheTrapzilla,a relativelynewgreaseinterceptordevicemanufacturedbythermaco,inc.retainedbythermaco,inc.as anindependentthirdpartyconsultant,eecevaluatedthetrapzilla fromdecember2011tojune2012. EEC compared the Trapzilla to a conventional concrete grease interceptor traditionally used for treatingwastewaterdischargefromafoodserviceestablishment(ashopthatmanufacturesandsells doughnuts)inthecityofbeaverton(city),oregon(figure1,sitelocationmap). 2.0 OBJECTIVES TheobjectiveofthestudywastocomparetheperformanceoftheTrapzilla totheperformanceofa conventionalconcretegreaseinterceptor.theevaluationisbasedonthefollowingfactors: Qualityofeffluent Visualassessmentofthedevice Inspectionsofthedownstreamprivatelateralusingclosedcircuittelevision(CCTV) Frequencyofmaintenance(i.e.,wastepumping) EECconductedsixindividualsitevisitstothesubjectfacilitytocollectwatersamples,observepumping events,andreviewdownstreamcctv(figure21,sitelayout). 1 EECisawastewaterconsultingcompanywithspecificexpertiseinfats,oils,andgrease(FOG)issues.In2004and2006,EEC conductedtwoofthelargestnationalfogcontrolstudiestodatefortheorangecountysanitationdistrict.eechasconducted numerousfogcharacterizationstudiesthroughouttheunitedstatesthatinvolvedgatheringevidenceoffogaccumulationin sewerlinesusingclosedcircuittelevision(cctv)inspectionandsamplingofgreaseinterceptors. W MAThermaco,Inc. 4 EEC

7 Trapzilla PerformanceEvaluation November15,2012 Figure21,SiteLayout 3.0 BACKGROUND LayoutofAllEvaluationElementsattheSubjectFacility As a highvolume food service establishment, the facility generates wastewater that requires pretreatment (namely, removal of oil and grease) prior to discharge to the City s sewer system. Approximately eight years ago, an inground, precast, 1,000gallon concrete grease interceptor was installedatthefacilitytoseparateoilandgreasefromthefacility swastewater.priortothisstudy,the concretegreaseinterceptorinplaceatthefacilitywasdeterioratingandnotfunctioningoptimally.the Cityrequiredthatthefailinggreaseinterceptorbereplacedwithanewunit.Duetothenatureofthe wastewater discharged from this facility (further discussed in Section 5.3), a new, corrosionresistant unitwaschosenforthefacility.forthispurpose,thermaco,inc.offeredtoinstallthetrapzilla grease interceptor. AccordingtoThermaco,thepatenteddesignoftheTrapzilla greaseseparatorusesbothhorizontaland vertical baffling surfaces to separate and retain higher volumes of grease/oils relative to the unit s internal volume. Thermaco, Inc. tested the Trapzilla using ASME A , Grease Interceptor Standard,andobservedthattheunitmaintainedaconsistent(flat)separationofgrease/oilupto85%of theunit sinternalvolume,whichisahigherretentioncapacitythanstandarddesignseparatorsthatuse verticalinletandoutletbaffleconfigurations. W MAThermaco,Inc. 5 EEC

8 Trapzilla PerformanceEvaluation November15,2012 TheTrapzilla unitinstalledatthefacilityisthemodeltz600withaninternalliquidvolumecapacityof 95gallons.TheTZ600wasinstalledinsidethewallsofthedismantledconcretegreaseinterceptor(see installationphotos)andsoilwasbackfilledintothesurroundingopencavityareas. Thermaco, Inc. agreed to compensate the facility for installation and evaluation of the new grease interceptor,andretainedeectoconductthestudy.thepartiesinvolvedandinterestedintheoutcome ofthestudyincludethecitypublicworksdepartment,whichmaintainsthebeavertonmunicipalsewer collection system; Clean Water Services (CWS), a water resources management utility in the Oregon TualatinRiverWatershed; 2 thefacilityowner;andthermaco,inc. Theconcretegreaseinterceptor,laterreplacedwiththeTrapzilla unit,islocatedimmediatelyoutside ofthesubjectfacility,northofnwcornellroad(figure21).theentrypointforcctvinspectionandjet flushing is located immediately adjacent to the grease interceptor location on the east side of the facility.thecctvinspectionandjetflushingwasconductedfromthecleanoutpointtothedownstream manholelocatedattheeastendofthefacility sparkinglot. 4.0 FIELDACTIVITIES FromDecember2011toJune2012,EECconductedsixindividualsitevisitsscheduledaccordingtothe pumpingfrequencyforeachdevice(table41,eecfieldvisitsandrelatedactivitiestodate).typically, a grease interceptor device must be pumped out before its contents reach 25% of its overall fluid capacity this is known as the 25% rule which is determined by using a probe or similar device to measurethefloatingandsettleablesolidmaterials(appendixa,25%ruleexample).thetotaloffloating andsettleablesolidmaterialsisthendividedbythetotalfluiddepthtodeterminethepercentageof accumulation. EEC used the 25% rule to establish the pumping frequency for the Trapzilla. Field evaluationswereconductedonamonthlybasistocoincidewiththepumpingfrequencyforthisdevice. Due to the level of degradation and apparent passthrough of solid materials causing downstream accumulation in the sewer system, the concrete grease interceptor had to be pumped biweekly. EEC conductedfieldworkeverytwoweekstocoincidewithbiweeklypumpingofthisunit. Table41,EECFieldVisitsandRelatedActivitiestoDate Task Start End GreaseInterceptorPerformanceEvaluation BaselineEstablishment December13,2011 December14,2011 PerformanceEvaluation1 December27,2011 December28,2011 PerformanceEvaluation2 February27,2012 February28,2012 Trapzilla UnitInstallation InstallationOversight February29,2012 March2,2012 Trapzilla UnitPerformanceEvaluation BaselineEstablishment March1,2012 March2,2012 PerformanceEvaluation1 March29,2012 March30,2012 PerformanceEvaluation2 April30,2012 May1,2012 PerformanceEvaluation3 June4,2012 June5,2012 Note: Performance Evaluation 2 for the concrete grease interceptor and Baseline Establishment for the Trapzilla were conductedduringthesamesitevisit. 2 CWSworkswith12membercitiestobuildandmaintainthepublicsanitarysewerandsurfacewatermanagementsystem. W MAThermaco,Inc. 6 EEC

9 Trapzilla PerformanceEvaluation November15,2012 The purpose of the first site visit (December 13 to 14, 2011) was to establish a baseline, or existing conditions, for the performance of the concrete grease interceptor. It was important to establish a baseline for each device to effectively evaluate their performance during the test period; followup evaluationswerecomparedtothesebaselineconditions.thebaselineevaluationincludedwastewater quality monitoring and condition assessment of the grease interceptor and the downstream private lateral.thekeycomponentofthebaselineevaluationwasensuringthattheconcretegreaseinterceptor and downstream sewer lines were thoroughly cleaned in order to demonstrate that the solids accumulationandsampleresultswererepresentativeoftheevaluationperiod.thebaselineandfollow upsitevisits(fromtheendofdecember2011throughfebruary2012)includedthefollowingactivities (Table41): Meetingwiththestaffandmanagementofthefacility Fieldanalysisofthewastewatereffluent(temperature,pH,andtotalsulfide) Collectionofwastewatereffluentsamplesforlaboratoryanalysis(totalsuspendedsolids[TSS], biologicaloxygendemand[bod],oilandgrease,totalsulfide,andph) Scrapingsamplingofsolidmaterials Visualinspectionofthegreaseinterceptor o InspectionofthedownstreamlateralusingCCTV(conductedbysubcontractor) Maintenance of the grease interceptor, including pumping and cleaning (conducted by subcontractor) Jetflushing/cleaningoftheprivatelateralline(conductedbysubcontractor) Afterthreemonthsofevaluation,theconcretegreaseinterceptorwasreplacedwithanewTrapzilla unit on March 1, The Trapzilla unit was installed by a contractor in the presence of EEC and representatives from Thermaco, Inc., the City, and CWS. The Trapzilla was evaluated in the same mannerastheconcretegreaseinterceptor. 4.1 WastewaterSamplingMethods This study consisted primarily of field and laboratory analysis of grab samples collected from the wastewatereffluent.duetothelackofapropersampleboxintheexistingconcretegreaseinterceptor, EEC used best professional judgment to collect the samples. Grab samples were collected using polyethylenecontainersof250or1,000milliliters;thesampleswerethentransferredtotheappropriate bottles for submittal to the laboratory for analysis (Figure 41, Effluent Sample Collection Points; Appendix B, Photos of Sample Collection and Monitoring). EEC determined that this method was appropriatesincethesampleswerecollectedforeffluentcomparisonpurposesandnotforregulatory purposes. The samples were submitted to the TestAmerica laboratory 3 in Beaverton, Oregon, under appropriatechainofcustodyprotocolsandwereanalyzedperu.s.environmentalprotectionagencyor standardmethods. 3 TestAmericaisalaboratorycertifiedintheStateofOregon. W MAThermaco,Inc. 7 EEC

10 Trapzilla PerformanceEvaluation November15,2012 Figure41,EffluentSampleCollectionPoints Effluent Effluent ConcreteGreaseInterceptor Trapzilla ThesamplescollectedwereanalyzedforBOD,TSS,oilandgrease,pH,anddissolvedsulfide. Biologicaloxygendemand:BODistheamountofoxygentakenupbymicroorganismsthatdecompose organicwastematterinwater;itisusedtomeasuretheamountofcertaintypesoforganicpollutantsin water.bodisoneofthemostcommonmeasuresofpollutantorganicmaterialinwater.foruntreated domesticwastewater,200milligramsperliter(mg/l)isconsideredamediumstrengthconcentrationof BOD. Total suspended solids: TSS is the amount of nondissolved solid material present in water or waste water.suspendedparticlesaretypicallyverysmallparticlesthatremaindispersedinaliquidthathas been turbulently mixed, which can create turbid or cloudy conditions. For untreated domestic wastewater,200mg/lisconsideredamediumstrengthconcentrationoftss. Oil and Grease: Oil and grease typically consists of compounds such as fats, soaps, fatty acids, hydrocarbons, waxes, and oils. Oil and grease analysis attempts to quantify compounds that have a greatersolubilityinanorganicsolventthaninwater,andmeasuresthelevelsofoilandgreasepresent inwater. ph: ph is a measure of the acidity or alkalinity of a fluid. The ph of any fluid is the measure of itshydrogenion(h + )concentrationrelativetothatofagivenstandardsolution.thephmayrangefrom 0to14,where0ismostacidic,14isthemostalkaline,and7isneutral. Dissolvedsulfide:Dissolvedsulfidedescribesanyofthreeclassesofchemicalcompoundscontainingthe elementsulfur: inorganic sulfides, organic sulfides, and phosphine sulfides. Organic sulfides were the mostcommontypesofdissolvedsulfidesidentifiedinthestudy.alowconcentrationofdissolvedsulfide (i.e., 20 mg/l or less) ) indicates a low probability of generating hydrogen sulfide and odors; a high concentration of dissolved sulfide (i.e., 50 mg/l or more) indicates a high probability of generating hydrogensulfideandodors. W MAThermaco,Inc. 8 EEC

11 Trapzilla PerformanceEvaluation November15, SAMPLINGRESULTS 5.1 WastewaterQuality ThelaboratoryresultsofthewastewatersamplescollectedaresummarizedinTable51,Wastewater EffluentLaboratoryResultsandAnalyticalMethods. Table51,WastewaterEffluentLaboratoryResultsandAnalyticalMethods Device Concrete Grease Interceptor Trapzilla ph SU TSS (mg/l) Parameter BOD 5 (mg/l) Oiland Grease (mg/l) Total Sulfide (ppm) Date SampleTime AnalyticalMethod SM4500 SM SM SM A H+B 25540D 5210B S2D 12/13/ , ND Beforepumping 12/14/ , ND Afterpumping 12/27/ ,400 ND ND Beforepumping 12/28/ ,400 5 ND Afterpumping 2/27/ ,080 ND Beforepumping Key:BOD 5 =biologicaloxygendemand ppm=partspermillion mg/l=milligramsperliter ND=nondetect ph=measureofacidityoralkalinity SU=standardunit 3/2/ , Afterdevice installation 3/29/ Beforepumping 3/30/ ,100 ND Afterpumping 4/30/ ,000 7 ND Beforepumping 5/1/ , ND Afterpumping 6/4/ ,100 1, ND BeforePumping 6/5/ ND AfterPumping SM=standardmethod SM4500H+B=StandardMethodforMeasuringpH SM25540D=StandardMethodforMeasuringTSS SM5210B=StandardMethodforMeasuringBOD SM 4500 S2D = Standard Method for Measuring Total Sulfide 1664A=StandardMethodforMeasuringOilandGrease TSS=totalsuspendedsolids The results of wastewater sampling show a general improvement in the quality of the wastewater collectedfromthetrapzilla unitversuswastewatercollectedfromtheconcretegreaseinterceptor.the ph of effluent from the Trapzilla was, on average, 1.11 SU higher than the ph of effluent from the concrete grease interceptor; the average ph was 4.8 for the Trapzilla effluent versus 3.69 for the concretegreaseinterceptoreffluent.ahigherphindicatesalessacidic,andthereforehigherquality, effluent. EffluentfromtheTrapzilla unitalsohadlowerbodconcentrationscomparedtotheeffluentsamples fromtheconcretegreaseinterceptor.onaverage,thestudyobservedadecreaseof4,662mg/linthe concentrationofbodwiththetrapzilla inplace;theaveragebodconcentrationwas2,012mg/lfor thetrapzilla versus6,674mg/lfortheconcretegreaseinterceptor. W MAThermaco,Inc. 9 EEC

12 Trapzilla PerformanceEvaluation November15,2012 EffluentfromtheTrapzilla unithadgenerallyhighertssconcentrationscomparedtoeffluentfromthe concretegreaseinterceptor.thestudyobservedanaverageincreaseof263mg/lintssconcentrations withthetrapzilla inplace;theaveragetssconcentrationwas650mg/lforthetrapzilla versus387 mg/lfortheconcretegreaseinterceptor. Oilandgreasemeasuredintheeffluentfrombothdeviceswasgenerallylow;mostlikely,thisisbecause thefacilitygenerallyusesmaterials,suchasrawdoughandfrostingmaterials,thatinherentlycontain very little oil and grease. Sulfides were not detected in any of the samples collected throughout the study.withthesulfideresultsbeinglessthan20mg/l,anyodorsorcorrosionisnotdirectlylinkedtothe presenceofsulfides. 5.2 ClosedCircuitTelevisionObservations Drain Away Rooter of Gladstone, Oregon, conducted CCTV inspections at the facility. The CCTV inspections were conducted in the downstream private sewer line for both the concrete grease interceptorandthetrapzilla unit.thecctvcameraisoperatedbypushingthecamerathroughthe sewerlineandthenrecordingtheobservationsasthecameraissmoothlypulledbackthroughtheline. Thecamerawasinsertedintothesewerlinethroughacleanoutaccessjustdownstreamofthedevice locations (Figure 11). Although the distance between the device and the downstream manhole is approximately 240 feet, the CCTV reel is approximately 200 feet in length, so only 200 feet of downstream sewer was televised at a time. The grease waste and sanitary sewer join 20 feet downstreamofthedevice. Theprivatesewerlinewasjetflushed/cleanedpriortotheinitialCCTVinspectiontoestablishabaseline forobservations.thejetflush/cleaningwasalsoconductedbydrainawayrooter.thecontentsofthe cleaning were captured in the downstream manhole by a certified pumping company. Since the concretegreaseinterceptorwaspumpedbiweekly,thefollowupcctvinspectionwasconductedtwo weeksafterthebaselinewasestablished. BaselineCCTVinspectionoftheconcretegreaseinterceptorwasconductedonDecember14,2012.Two weeksaftertheprivatesewerlinewascleaned,anoticeableaccumulationwasobservedintheprivate sewer line downstream of the concrete grease interceptor (Figure 51, CCTV Observations of Concrete GreaseInterceptor).CCTVinspectionwasconductedbeforetheconcretegreaseinterceptorwasremoved onfebruary28,2012,butthatcctvrecordingwaslostduetotechnicaldifficulties.thedrainawayrooter representativestatedthatsignificantaccumulationwasobservedinthedownstreamprivatesewerline. W MAThermaco,Inc. 10 EEC

13 Trapzilla PerformanceEvaluation November15,2012 Figure51,CCTVObservationsDownstreamoftheConcreteGreaseInterceptor PrivateSewer51 1 DownstreamofConcreteGrease PrivateSewer51 2 DownstreamofConcreteGrease InterceptorImmediatelyAfterCleaningon12/14/ InterceptorTwoWeeksAfterCleaningon12/28/2011 The baseline CCTV inspection of the Trapzilla was conducted on March 2, For the Trapzilla baseline, the downstream private sewer line was also cleaned prior to CCTV. Since a onemonth pumpingfrequencywasestablishedforthetrapzilla,thefollowupcctvinspectionswerescheduled ononemonthintervals. Figure52,CCTVObservationsoftheTrapzilla Unit,belowcomparestheconditionoftheprivatesewer line66to67feetdownstreamofthetrapzilla immediatelyandtwomonthsaftertheinstallationand cleaning. Figure52,CCTVObservationsDownstreamoftheTrapzilla Unit PrivateSewer66 10 DownstreamofTrapzilla ImmediatelyAfterInstallationandCleaningon 3/2/ PrivateSewer67 5 DownstreamofTrapzilla Two MonthsAfterInstallationandCleaningon5/1/2012 Theamountofaccumulationobservedinthedownstreamprivatesewerlinewassimilarforbothdevices. However,CCTVFiguresoftheconcretegreaseinterceptortakentwoweeksafterbaselineconditionsand Figures of the Trapzilla unit taken two months after baseline conditions show less accumulation in the downstreamsewerlineaftertheinstallationofthetrapzilla. 4 TheCCTVimageisnothighquality.Watershowninthepictureisrelativelyclearwithnoapparentaccumulation. 5 TheCCTVimageisnothighquality.Watershowninthepictureisrelativelyclearwithnoapparentaccumulation. W MAThermaco,Inc. 11 EEC

14 Trapzilla PerformanceEvaluation November15,2012 The City also conducted CCTV inspections of its downstream sewer lines in May 2012, three months after the installation of the Trapzilla unit. Figure 53, CCTV Observations Conducted by the City of Beaverton,showsthesewerlineimmediatelydownstreamandtwosegmentsdownstream,respectively, ofthefacility sprivatesewerline. Figure53,CCTVObservationsConductedbytheCityofBeaverton PublicSewerImmediatelyDownstreamoftheFacility PrivateSewerLine,May2012 PublicSewerTwo SegmentsDownstreamoftheFacility PrivateSewerLine,May2012 InFigure53,theimageontheleftshowssignificantlylessaccumulationimmediatelydownstreamof the facility s private sewer line, whereas the image on the right shows higher accumulation two segments downstream of the sewer line. Higher accumulation further downstream could be due to sagginginthedownstreamsewerlineorsettlingofthematerialsovertime.sincecctvinspectionwas conductedonlyaftertheconcretegreaseinterceptorwasremoved,theaccumulationsobservedduring CCTVobservationscould notbecomparedtoaccumulations thatoccurred while the concretegrease interceptorwasinplace. 5.3 ScrapingSampling Another potential explanation for accumulation observed in Figure54,AcetobacterXylinum the downstream sewer line is the presence of Acetobacter. 6 Scrapingsamplesofthematerialsaccumulatedin thedevices anddownstreamsewerlinewerecollectedperiodicallyduring the study period. The samples were sent to Sustainable ScientificSolutionsforanalysis,whichconfirmedthepresence ofacetobacterinthesamples.acetobactertypicallyattachesto thewallsofthedevicesandsewerlinesintheformofcellulose. The Acetobacter breaks down the sugars and produces acetic acid. This could also account for the low ph discussed in Section5.1. ThelowpHofthewastewaterinthegreaseinterceptor(i.e.,pH AcetobacterMagnified10,000Times less than ) is most likely the cause for the deterioration of the concrete grease interceptor. Acid 6 Agenusofaceticacidbacteriacharacterizedbytheabilitytoconvertethanoltoaceticacidinthepresenceofoxygen. 7 ApHabove5.0isthenationalpretreatmentstandardforwastewaterdischargefromfacilities. W MAThermaco,Inc. 12 EEC

15 Trapzilla PerformanceEvaluation November15,2012 typicallywillattackconcrete scompositionandweakenitovertime.thisprocessisacceleratedwhen theconcretemixqualityisloworiflimestone,whichisinherentlysoft,isusedastheaggregate.the qualityofconstructionmaterialsusedfortheconcretegreaseinterceptorisunknown.certainmeasures can be taken to enhance the quality of the concrete (e.g., admixtures, coatings, and higher fly ash concentrations),butthesemeasuresgenerallywillonlyslowdownthedeteriorationovertime.atypical concrete gravity grease interceptor in normal ph conditions (i.e., ph above 6.5) should last 30 to 40 years, but the concrete grease interceptor at this location failed after only eight years. For these reasons,apretreatmentdevicethatismadeofasyntheticorpolypropyleneplasticmaterialwouldbe moreappropriateforlowphconditions.thesetypesofmaterialsarefarmoreresistanttoacidicwater conditions. 5.4 DyeTesting Dye testing investigations were conducted within the facility to determine if the necessary grease bearingdrainswereconnectedtothegreasecontroldevices.liquid,fluorescentgreendyewasapplied to each sink and drain within the facility s kitchen area. Observations were then made within the concretegreaseinterceptoranddownstreammanholetoobservewherethedyeappeared.sufficient timewasprovidedbetweendyeapplicationstoensurethatthedischargepathofeachdrainwasclear. Dyetestingwasimportantbecausetheabsenceofaconnectionbetweenagreasewastedrainandthe greasecontroldevicecouldleadtoaccumulationofgreaseorsolidsinthedownstreamsewersystem. Typically, proper measures are taken at the time of construction and plan review to ensure that the properdrainsareconnected,butforthepurposesofthestudyandintheabsenceofasbuiltplumbing drawings,dyetestingwasnecessary. Figure 55, Dye Testing Observations, shows the presence of dye in the sewer system and concrete greaseinterceptor.theresultsofthedyetestindicatedthatthemajorityofthegreasewastesdrained properlytothegreasecontroldevices;oneareaofthefacility skitchen,however,draineddirectlyto thesewersystem.thisareawasidentifiedasthestationwherecoffee,cappuccino,andicecreamare made. The wastewater discharged in these drains could be a potential cause of accumulation in the downstreamsewersystem,andcouldaccountforthematerialaccumulationseeninthecctvimages. Figure55,DyeTestingObservations DyeObservedinInletofConcreteGreaseInterceptor DyeObservedinDownstreamManholeofPrivate SewerLine W MAThermaco,Inc. 13 EEC

16 Trapzilla PerformanceEvaluation November15, PumpingObservations DarlingInternationalofPortland,Oregon,pumpedandcleanedtheconcretegreaseinterceptorandthe Trapzilla unit.thepumpingwasconductedatmidnighttoavoidinterferencewiththefacility snormal operations. An EEC representative was present onsite to inspect and document the condition of the devicebytakingphotographsaftereachpumpingevent. The City required the concrete grease interceptor to be pumped biweekly due to the deteriorated condition and apparent passthrough of solids from the unit. Figure 56, Concrete Grease Interceptor Observations,takenafterpumpingofthegreaseinterceptor,showsthedeteriorationoftheconcrete walls and exposed rebar inside the concrete grease interceptor. Even with the deteriorated concrete andexposedrebar,darlinginternationalwasabletocleantheconcretegreaseinterceptorefficiently. Figure56,ConcreteGreaseInterceptorObservations Exposed Aggregate Exposed Rebar ConcreteGreaseInterceptorImmediatelyAfter Pumpingon12/14/2011 ConcreteGreaseInterceptorImmediatelyAfter Pumpingon12/28/2011 The Trapzilla unit was pumped on a monthly basis since installation. The pumping frequency was determinedbyusinganenvironmentalbiosolutions,inc.dipstickprobetomeasurethesettledsolids and floatables in the Trapzilla (see Appendix B). To date, there has been no need to increase the pumpingfrequency. Figure 57, Trapzilla Unit After Pumping, shows the inside of the Trapzilla after thorough pumping; the photoontheleftshowsthepumpingofthesolidscompartmentofthetrapzilla.thematerialsdidnot adheretoorsolidifyonthewallsofthetrapzilla unit,andtheslopedfunnelshapeofthetrapzilla forced thesolidmaterialstothecenter,wheretheycouldberemovedbythesuctionnozzle.however,duetothe configuration of the Trapzilla, it was difficult to see whether all residual solids were removed during pumping. W MAThermaco,Inc. 14 EEC

17 Trapzilla PerformanceEvaluation November15,2012 Figure57,Trapzilla UnitAfterPumping InterioroftheTrapzilla ImmediatelyAfterPumpingon 3/30/2012 Interior ofthetrapzilla ImmediatelyAfterPumpingon 5/1/ CONCLUSIONS Based on evidence from the evaluation, EEC determined the following differences in performance betweenthetrapzilla andthestandardconcretegreaseinterceptor: BOD:Onaverage,BODconcentrationswerelowerintheTrapzilla effluentthanintheexisting grease interceptor effluent, indicating that the Trapzilla performed better in reducing the concentrationofboddischarged. ph:onaverage,phlevelswerehigher(indicatingloweracidity)inthetrapzilla effluentthanin theexisting greaseinterceptoreffluent.the Trapzilla iscomposedofsyntheticmaterial that appears to be more suitable for this particular facility, considering the lower ph conditions inherent in the wastewater discharged at the facility, and should last longer than a typical concretegreaseinterceptoratthisfacility.thefacilityowneriscurrentlyresearchingpossible solutionstothelowphlevelsofitswastewaterdischarge. Downstream Accumulation: As observed through CCTV inspections, less residual material accumulated in the downstream private sewer line with the Trapzilla in place. The study indicatedthataccumulationisoccurringinthecity sdownstreampublicsewerlineandnotin thefacility sprivatesewerline.sincecctvinspectionwasnotperformedonthecity ssewer line for comparison while the concrete grease interceptor was still in place, a definitive conclusioncouldnotbemade.theevidencesuggeststhatthetrapzilla wasmoreeffectiveat preventingmaterialfrompassingintothedownstreampublicsewerline.however,therewas someaccumulationobserveddownstreamofbothdevices. It should be noted that the downstream accumulation could be due to discharge from the greasewastedraininthefacility skitchenareathatwasnotconnectedtothegreasecontrol devices(seesection5.4).thefacilitywillmakethenecessaryplumbingchangestoredirectthe unconnecteddraintothetrapzilla. W MAThermaco,Inc. 15 EEC

18 Trapzilla PerformanceEvaluation November15,2012 The Acetobacter developing in the concrete grease interceptor and the Trapzilla is likely the cause of the material accumulation in the grease interceptor device and in the downstream sewersystem;furtherinvestigationisneededtodeterminewhetheracetobacteristheculprit. Maintenance Frequency: During the study, the Trapzilla required less frequent maintenance (once per month) than the concrete grease interceptor (biweekly). A properly functioning concretegreaseinterceptorwouldlikelyrequirelessfrequentpumping. TSS:Onaverage,TSSconcentrationswerehigherintheTrapzilla effluentthanintheexisting greaseinterceptor.thestudycouldnotdeterminewhethertssconcentrationsarethecauseof thedownstreamaccumulationobservedinthecctvinspections. Oil and Grease: Oil and grease concentrations are significantly lower in the facility s effluent thaninwastewaterfromotherfoodserviceestablishments,suchasrestaurants;thissuggests thatseparationandremovalofoilandgreasemaynotbeanissueofconcernwiththefacility s wastewater. W MAThermaco,Inc. 16 EEC

19 FIGURE 1

20 SITE LOCATION MAP Legend Subject Facility Beaverton, OR Site Location File: PM: Author: Project Number: W-2263 SiteLocation.mxd JS RG Miles Date: 9/13/2012 Figure 1

21 APPENDIX A 25% RULE EXAMPLE

22 Trapzilla Performance Evaluation November 15, % RULE Typically a device is required to be pumped out prior to its contents reaching 25% of the overall fluid capacity (the 25% rule). This is determined by using an Environmental Bio Solutions, Inc. Dip Stick Pro or similar device to measure the floating and settleable solid materials. The total materials are then divided by the total fluid depth to determine the percentage of accumulation: Floatable Materials + Settled Solids = Total Accumulation Total Accumulation / Total Fluid Depth = Percentage 25% Rule Examples Accumulation Is Less Than 25% Accumulation Is Greater Than 25% W MA Thermaco, Inc. A-1 EEC

23 APPENDIX B PHOTOS OF SAMPLE COLLECTION AND MONITORING

24 Trapzilla Performance Evaluation November 15, ,000 ml Container Used to Collect Wastewater Samples from the Trapzilla 1,000 ml Container Submerged in the Trapzilla Effluent Pipe W MA Thermaco, Inc. B-1 EEC

25 Trapzilla Performance Evaluation November 15, 2012 Dip Stick Probe Used to Verify the Pumping Frequency Level of Solids Accumulated at the Bottom of the Dip Stick Probe W MA Thermaco, Inc. B-2 EEC