Welcome! Regulations Basics Session #6 Disinfection Byproducts Rule WELCOME!

Transcription

1 Welcome! Regulations Basics Session #6 Disinfection Byproducts Rule WELCOME! This training is presented by RCAC with funding provided by the California State Revolving Fund (SRFCA) from the California State Water Resources Control Board, Division of Drinking Water (DDW) 1

2 Your Moderator Today Neil Worthen Las Cruces, NM The Rural Community Assistance Partnership RCAC 2

3 Affordable housing Community facilities RCAC Programs Water and wastewater infrastructure financing (Loan Fund) Classroom and online training On-site technical assistance Median Household Income (MHI) surveys Communication Tour Introduction to the online Virtual Classroom 3

4 Audio set up wizard. If you can t hear us, click here and follow directions Audio/Volume Controls 4

5 Hand raising Chat Box 5

6 Type questions and comments in lower box Text Chat In the chat box to the left, type the name of your agency and number of service connections (or population) 6

7 Moderators live! Participant List Shows who is in the room 7

8 If you need to step away Emoticons 8

9 Polling Responses Poll Question How much experience do you have with online learning? A. Extensive B. Considerable C.Some D.Little or none 9

10 The Whiteboard Whiteboard Tools 10

11 Symbols Use the whiteboard tools to place a symbol near your location 11

12 Whiteboard text entry Click the LARGE letter A Choose your color 12

13 Who s Here Today? Operators Managers Board Members Other Publicly Owned Privately Owned <500 Connections Connections >3000 Connections Hollow circle & square 13

14 Choose your color Circles And Squares... Which Countries Have You Visited? Iraq India USA Canada Vietnam Ireland Australia Mexico Afghanistan New Zealand Thailand Indonesia Egypt 14

15 Line tool Choose your color 15

16 Line Tool Famous People Claude Monet Frank Lloyd Wright George Patton Rush Limbaugh Whoopi Goldberg Charles Dickens Angelina Jolie Military Literature Acting Art Architecture Television Radio Line Tool Famous People Claude Monet Frank Lloyd Wright George Patton Rush Limbaugh Whoopi Goldberg Charles Dickens Angelina Jolie Military Literature Acting Art Architecture Television Radio 16

17 Tools We ve Covered Microphone Hand raising & other icons Text box Whiteboard tools Polling questions Questions? Text your questions and comments anytime during the session 17

18 Today s Presenter Stevan Palmer Regional Environmental Manager AK, OR, WA spalmer@rcac.org Regulations Basics Online Session #6 Disinfection Byproducts Rule Citations based on July 1, 2014 Blue Book 18

19 Regulations Basics Online Learning Objectives Provide the water system Operator with a working knowledge of the California Safe Drinking Water Act regulations Improve compliance with regulations Provide safer water in your water system Session #6 Disinfection Byproducts Rule Your disinfection treatment process can (most likely does) produce unwanted and sometimes harmful byproducts The Disinfection Byproducts Rule (DBPR) sets limits for exposure to DBPs 19

20 Today s Agenda Pre-Test Background Importance of Disinfection History / development of DBPR DBPR requirements Post-Test Additional Resources Pre-Session Quiz 20

21 Today s Agenda Pre-Test Background Importance of Disinfection History / development of DBRP DBPR requirements Post-Test Additional Resources Chlorination is a good thing Generally recognized as one of the greatest public health advances in the 20 th century At the beginning of the century: Dysentery was the third leading cause of death in America Typhoid claimed 150 out of every 100,000 Americans every year Cholera was endemic in US cities 21

22 Here s where chlorination began Jersey City The use of chlorination in drinking water treatment Reduced the mortality rate in the average American city by 43 percent Even more significantly, the death rate for babies dropped by 74 percent ( The point is, as we talk about disinfection byproducts it must be remembered that the benefits of chlorination / disinfection far outweigh the risks of its byproducts) 22

23 TANSTAAFL* : Chemical disinfection in drinking water treatment can (and does) form unwanted and possibly harmful chemicals (byproducts) TANSTAFFL: There Ain t No Such Thing As A Free Lunch DBPR: Finding the Balance Microbial Disinfection Disinfection Byproducts 23

24 Chemical Disinfectants used in drinking water treatment Chlorine (elemental gas, hypochlorite) Chloramines Ozone Chlorine dioxide These chemicals are not new to water treatment Disinfectant First Used Chlorine 1908 Chloramines early 1900s Ozone 1893 Chlorine Dioxide 1920s 24

25 Polling Question: What disinfectant is used in your water System? A. Chlorine (gas, hypochlorite) B. Chloramines C. Ozone D. Chlorine dioxide E. Combination of some of the above Disinfection Byproducts are Complex!!!! 25

26 Disinfection Byproducts Disinfectant organohalogenic disinfection byproducts inorganic disinfection byproducts non-halogenic disinfection byproducts chlorine (Cl 2 )/ hypochlorus acid (HOCl) trihalomethanes, halogenic acetic acids, haloacetonnitrils, chlorine hydrates, chloropicrin, chlorophenols, N- chloramines, halofuranones, bromohydrins chlorate (particularly the application of hypochlorite) aldehydes, alkanic acids, benzene, carboxylic acids Chlorine dioxide (ClO 2 ) chlorite, chlorate unknown chloramines (NH 3 Cl etc.) haloacetonnitrils, cyano chlorine, organic chloramines, chloramino acids, chlorohydrates, haloketons, nitrite, nitrate, chlorate, hydrazine aldehydes, ketons ozone (O 3 ) bromate, bromoform, monobromine acetic acid, dibromine acetic acid, dibromine aceton, cyano bromine chlorate, iodate, bromate, hydrogen peroxide, underbromic acid, epoxy, ozonates aldehydes, ketons, ketoacids, carboxylic acids Regulated Disinfection Byproducts Disinfectant Chlorine Chloramines Ozone Chlorine Dioxide Byproduct(s) Produced Trihalomethanes, Haloaccetic acids Nitrification (nitrate / nitrite) Bromate Chlorite 26

27 Review: Disinfection Byproducts Haloacetic acids Chlorine Chloramines Ozone Bromate Chlorite Chlorine dioxide Trihalomethanes Nitrate/Nitrite (line tool exercise) Review: Disinfection Byproducts Haloacetic acids Chlorine Chloramines Ozone Bromate Chlorite Chlorine dioxide Trihalomethanes Nitrate/Nitrite (line tool exercise) 27

28 If we ve been using these disinfectants for the past 100 years why are we just now regulating their byproducts? These byproducts are found in very low concentrations Until the 1970s/1980s analytical methods did not exist to detect and measure these compounds The benefits of chemical disinfection far outweigh the risks of byproducts so changes to treatment and regulation must be careful Today s Agenda Pre-Test Background Importance of Disinfection History / development of DBRP DBPR requirements Post-Test Additional Resources 28

29 DBPR Timeline THMs found in drinking water distribution systems 1979 THM MCL set at 100 ppb (>10,000 population systems) 1998 Stage 1 DBPR THM MCL 80 ppb HAA MCL 60 ppb Chlorite MCL 1 mg/l Bromate MCL 10 ppb MRDLs for chlorine, chloramines & ClO 2 DBPR Timeline - Continued 2006 Stage 2 DBPR Locational Running Annual Average for THM and HAA compliance Individual Distribution System Evaluation (IDSE) 29

30 Today s Agenda Pre-Test Background Importance of Disinfection History / development of DBRP DBPR requirements Post-Test Additional Resources DBPR Requirements Applies to all community and nontransient noncommunity systems that treat their water with a chemical disinfectant or supply water that contains a chemical disinfectant. Transient systems that use chlorine dioxide must comply with requirements for chlorine dioxide and chlorite 30

31 DBPR Requirements System serving >10,000 population must comply with IDSE requirements. DBPR Requirements: MCLs Disinfectant Byproduct Total Trihalomethanes (TTHM) Bromodichloromethane Bromoform Chloroform Dibromochloromethane Haloacetic acids (HAA5) Monochloracetic acid Dichloroacetic acid Trichloroacetic acid Monobromoacetic acid Dibromoacetic acid Bromate Chlorite MCL (mg/l) mg/l mg/l mg/l 1.0 mg/l 31

32 DBPR Requirements: MRDLs Disinfectant Residual Chlorine Chloramines Chlorine Dioxide MRDL 4.0 mg/l 4.0 mg/l 0.8 mg/l MRDL Maximum Residual Disinfectant Level DBPR Requirements: Monitoring Except for field tests (ph, alkalinity, chlorine residual, chlorine dioxide residual) all compliance analyses will be run in a certified laboratory. Systems must take all samples during normal operating conditions Failure to properly sample/monitor will result in Public Notification 32

33 DBPR Requirements: TTHM & HAA Monitoring Type of System Population Served Minimum Monitoring Frequency Surface Water >5,000, dual sample sets/ quarter 1,000,000 to 4,999, dual sample sets/ quarter 250,000 to 999, dual sample sets/ quarter 50,000 to 249,999 8 dual sample sets/quarter 10,000 to 49,999 4 dual sample sets/ quarter 3,301 to 9,999 2 dual sample sets /quarter 500 to 3,300 1 THM and 1 HAA / quarter <500 1 THM and 1 HAA /year Groundwater (not GWUDISW) >500,000 8 dual sample sets/quarter 100,000 to 499,999 6 dual sample sets/ quarter 10,000 to 99,999 4 dual sample sets/ quarter 500 to 9,999 2 dual sample sets /year <500 1 sample per year/ plant Reduced monitoring frequency is allowed if THMs are <40 ppb and HAAs are <30 ppb DBPR Requirements: Monitoring Chlorine Dioxide / Chlorite Systems using chlorine dioxide must monitor for chlorite: Daily grab sample at the POE If daily grab is >MCL, take three additional sample from distribution system Three sample set from the distribution system monthly 33

34 DBPR Requirements: Monitoring Ozone / Bromate Systems using ozone must monitor for bromate: Monthly grab sample at the POE under normal operating conditions If daily grab is >MCL, take three additional sample from distribution system Three sample set from the distribution system monthly DBPR Requirements: Disinfectant Residual Monitoring Systems using chlorine or chloramine in the distribution system must monitor residuals: At the same points and at the same time as total coliforms are sampled 34

35 DBPR Requirements: DBP Precursor Monitoring Surface water systems using conventional treatment: One paired TOC sample (source water and treated water) per month One source water alkalinity per month If annual average treated water TOC is >2.0 mg/l reduced monitoring is possible DBPR Requirements: DBP Precursor Treatment Surface water systems using conventional treatment shall operate to achieve TOC removal percentages (Enhance Coagulation) Source water alkalinity (mg/l as CaCO 3 ) Source Water TOC, mg/l 0-60 > >120 >2.0 to % 25% 15% >4.0 to % 35% 25% >8.0 50% 40% 30% 35

36 What Are Trihalomethanes? Organic compound formed in the chlorination process Four compounds make up the trihalomethane group Chloroform Dichlorobromomethane Dibromochloromethane Bromoform H Br C Br Br H Cl C Cl Cl H Br C Cl Cl H Br C Cl Br Where Do THMs Come From? Naturally Occurring Organics in Raw Water + Chlorine THMs 36

37 Why don t we want THMs in our water? Possible human carcinogen MCL 80 ppb Must meet MCL at Locational Running Annual Average How do we keep THMs out of our water? Naturally Occurring Organics in Raw Water + Chlorine THMs Minimize exposure between organics in the water and chlorine applied 37

38 THM Formation Control Strategies Minimize organics concentration exposed to chlorine Reduce organics in raw water New source Source water protection Control algae blooms PAC, GAC, IX, RO, chemical oxidation Remove organics in treatment process (sedimentation / filtration) before chlorination THM Formation Control Strategies Minimize chlorine applied in treatment process Measure disinfection more effectively Tracer studies Improved monitoring Apply chlorine more effectively Multiple application points Improved mixing Use less chlorine Review your plant s CT requirements Change type of disinfectants 38

39 THM Formation Control Strategies Optimize CT Calculations Use tracer studies to optimize the T in CT Install continuous monitors to avoid worst case inactivation calculations THM Formation Control Strategies Minimize water age in distribution system AWWA: Water age for average and dead end conditions 39

40 THM Formation Control Strategies Minimize water age in distribution system Loop dead end mains Chlorine booster stations in distribution system Flushing program Automatic flush valves Cross connection control THM Formation Control Strategies Examine storage tanks design and O&M Design inlets/outlets to maximize turbulence & mixing Reduce retention time Ensure turnover (mechanical mix?) Remove sediments/biogrowth 40

41 THM Removal Strategies Storage tank aeration Important Notice!!!! USE OF ANY OF THESE ACTIONS REQUIRES PRIOR APPROVAL FROM DDW 41

42 Post-Session Quiz Session Evaluation 42