Talking about Chloramines: A Discussion of the Concerns and Questions Regarding Water Treatment

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1 No part of this presentation may be copied, reproduced, or otherwise utilized without permission. Talking about Chloramines: A Discussion of the Concerns and Questions Regarding Water Treatment September 15, 2016

2 Ben Stanford, PhD Director of Applied Research Hazen and Sawyer and Mark LeChevallier, PhD Vice President, Chief Environmental Officer American Water

3 Objective To provide a balanced overview of the scientific evidence about chloramine use, including disinfection by-products, health concerns, environmental concerns, and infrastructure concerns.

4 WRF Resources Conversion to Chloramine and Process Optmization Optimizing Chloramine Treatment: Second Edition (project # 2760) A Guide for the Implementation and Use of Chloramines (project # 2847) Long-Term Effects of Disinfection Changes on Water Quality (project # 2940) Nitrification Chloramine Decomposition in Distribution System and Model Waters (project # 937) Ammonia from Chloramine Decay: Effects on Distribution System Nitrification (project #553) Lead and Copper Leaching Effect of Changing Disinfectants on Distribution System Lead and Copper Release (project #3107) The Role of Free Chlorine, Chloramines, and Natural Organic Matter in the Release of Lead into Drinking Water (project # 3172) 4

5 WRF Resources Disinfection By-Products Quantifying Hydrazine in Chloraminated Water (project #4141) Formation of Hydrazine as a Chloramine By-Product (project #2997) Controlling the Formation of Nitrosamines During Water Treatment (project # 4370) Elastomeric Material Degradation Performance of Elastomeric Components in Contact with Potable Water (project #2932)

6 Agenda Framing the Issue: A Heated Debate Disinfection, Compliance, DBPs Discussion of Specific Concerns From DBPs and Rashes to Pipes and Fish

7 Framing the Issue: A Heated Debate Stockton residents dispute chloramines, water rate hikes - KCRA Sacramento, March 27, 2016 WATER WORRIES: BPW, anti-chloramine group argue how to handle disinfecting Hannibal water supply - Quincy Herald Whig (IL), May 10, 2016 Group opposes city s plan for chloramine disinfection - KRBD (AK), February 5, 2014

8 A Long History of Chloramine use s 1940s 1970s First full-scale free chlorine use in Chicago First use of chloramine in Denver for T&O Control 16% usage rate in the United States Need for ammonia during WWII decreased availability for H 2 O disinfection and use declined over next few decades Organic DBPs discovered J. J. Rook MCL for TTHM set at 100 μg/l 18 % of systems using chloramine primarily for regulatory compliance MCL for THMs set at 80 μg/l; HAA5 set at 60 μg/l U.S. chloramines use estimated at >30% *Adapted from M. McGuire 2001

9 45% of U.S. Population Is Served by Public Water Supplies Using Chloramine Data Courtesy of Chad Seidel, Corona Environmental Consulting Analysis of EPA UCMR3 Data Percent of U.S. Population on Public Water Supply Using Chloraminated Water 1.6% 100,000,000 people in United States use chloraminated water 44.9% 53.6% Equates to around 30% of Public Water Supply Systems Using Free Chlorine Using Chloramine Unclassified

10 Above All, Public Health Protection is the #1 Priority We must achieve public health protection in a fiscally and environmentally responsible manner Many tools will get us to our goals As scientists and engineers, we evaluate options at each location Includes a thorough evaluation of risks and benefits Free chlorine and chloramine are not interchangeable Both require different approaches to managing water quality

11 Utilities constantly balance multiple compliance objectives to protect public health

12 With Nearly Half of Public Water Supplies on Chloramine, Is There a Concern? Long history of chloramine use A significant portion of U.S. cities, including those with major schools of public health, pharmaceutical industries, and food/beverage production centers, use chloramine But there ARE real issues and concerns that must be taken into consideration Chloramine is not a universal solution

13 Today s Goal: Discuss Topics That Have Been Raised Regarding Chloramine Use Topics of Discussion/Concerned Citizen Questions Disinfection: Is monochloramine a weaker disinfectant than chlorine? Disinfection By-products: Does chloramine use produce more DBPs like NDMA and iodinated byproducts? Nitrification: Can improper management of chloraminated systems can lead to nitrification? Other Health Effects: People have complained of skin rashes and asthma in chloraminated systems what do we know about this? Lead Contamination: Conversion from free chlorine to chloramine has occurred with increased lead levels is chloramination to blame? Fish Kills: Water main breaks with chloraminated water have resulted in fish kills will this happen in my community? Premise Plumbing: Monochloramine can attack rubber gaskets and flapper valves in toilets will our plumbing system fail?

14 Discussion of Specific Topics Related to Chloramine Use

15 Disinfection Chloramines are a weak disinfectant. Source: Adapted from LeChevallier, M. W., C. D. Cawthon, and R. G. Lee Inactivation of biofilm bacteria. Copyright American Society for Microbiology, Applied and Environmental Microbiology 54(10): Free chlorine is preferred over chloramines as a primary disinfectant

16 Relationship between Disinfection and AOC on Coliform Occurrences System AOC Level % Samples Avg. Coliform (ug/l) Positive /100 ml Free Chlorinated Systems, N= Chloraminated Systems, N= Source: LeChevallier, M. W., N. J. Welch, and D. B. Smith Full-scale studies of factors related to coliform regrowth in drinking water. Copyright American Society for Microbiology, Applied and Environmental Microbiology 62(7): Free chlorinated systems with high AOC had 87% higher occurrence rate, and bacterial levels 19 times higher than low AOC At high AOC levels, free chlorine systems had 42% more coliforms at systems. densities 49 times higher than chloraminated systems. Chloraminated systems with high or low AOC were not statistically different. At lower AOC levels, free chlorine systems had 89% more occurrence, at 4 times higher levels. 16

17 Impact of Pipe Surface on Disinfection of Biofilm Bacteria Decrease Log Viable Count (CFU/cm²) Free 1 mg/l Mono 1 mg/l Free 4 mg/l Mono 4 mg/l Iron Galvanized Copper PVC Source: LeChevallier, M. W., C. D. Lowry, and R. G. Lee Disinfecting biofilms in a model distribution system. Journal AWWA 82(7): American Water Works Association. Reprinted with permission. 17

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20 Lessons from Real Life: San Francisco, CA 53 buildings Sampled 3 times pre- and post-conversion to chloramines Sampled hot water heater and four distal sites Sampled swab and water from distal sites Surveys collected data on building age, height, type and number of hot water heaters ph, temperature, free or total Cl 2 residual measured for each sample Source: Flannery, B., L. B. Gelling, D. J. Vugia, J. M. Weintraub, J. J. Salerno, M. J. Conroy, V. A. Stevens, C. E. Rose, M. R. Moore, B. S. Fields, and R. E. Besser Reducing Legionella colonization of water systems with monochloramine. Emerg. Infect. Dis. 12(4):

21 Round 1 Heater #2 #3 #4 #5 #6 #7 #8 #9 Round 2 Heater #2 #3 #4 #5 #6 #7 #8 #9 Round 3 Heater #2 #3 #4 #5 #6 #7 #8 #9 Round 4 Heater #2 #3 #4 #5 #6 #7 #8 #9 Round 5 Heater #2 #3 #4 #5 #6 #7 #8 #9 Round 6 Heater #2 #3 #4 #5 #6 #7 #8 #9 Free Chlorine Chloramine 21

Legionella and Amoebae Intracellular Legionella in: Acanthamoeba, Amoeba,

Vahlkamfia, Tetrahymena, Dictyostelium Legionella survive for months, resistant

virulence, replication Legionella-containing vacuoles expelled prior to

22 Legionella and Amoebae Intracellular Legionella in: Acanthamoeba, Amoeba, Comandonia, Echinamoeba, Filamoeba, Hartmannella, Naegleria, Paratetramitus, Vahlkamfia, Tetrahymena, Dictyostelium Legionella survive for months, resistant to 50 mg/l free chlorine for 18 hr Coated with amoebal proteins Increases virulence, replication Legionella-containing vacuoles expelled prior to encystation Trophozoite stage sensitive to disinfectants (CT 99.9 = 1.5 mg-min/l) Trophozoite Cyst 22

Trophozoite Concentration Utility Trophs Trophs 25 C 42 C TX - #27 74 82 FL - #30 59 73 CA - #4 68 73

23 Trophozoite Concentration Utility Trophs Trophs 25 C 42 C TX - # FL - # CA - # FL - # CA - # AZ - # Data courtesy of WateReuse Research Foundation Chloramines

24 Drinking Water Disease Outbreaks, Morbidity & Mortality Weekly Report. 64(31): , August 14,

25 Strategy For Managing Distribution System Integrity Chloraminated Systems Control Intrusion Pressure Management Leak Detection Main Break/Repair Sewer Separation/Leakage Nitrification Control Control Water Age Cross Connection Control Corrosion Control/Material Compatibility Maintain Storage Facilities Security Free Chlorinated Systems Control Biofilms Organic Carbon Control Measure/Reduce AOC Disinfectant Residuals Biological Treatment DBP Control Control Water Age Cross Connection Control Corrosion Control/Material Compatibility Maintain Storage Facilities Security 25

26 Disinfection By-products (DBPs) Does chloramine use produce more DBPs like NDMA and iodinated byproducts?

27 In Reality, Disinfectant Choice Will Always Be Associated with DBP Formation DBPs Preferential to Chlorine DBPs Associated with Chlorine and Chloramine Haloketones THMs Iodoacids DBPs Preferential to Chloramine Haloacetaldehydes HAAs Nitrosamines (e.g., NDMA) Halogenated Furanones Haloacetonitriles Cyanogen Halides (MX) Halonitromethanes Haloacetamides Halobenzoquinones Iodo THMs Source: Adapted from Hrudey, S. E., and J. W. A. Charrois, eds Disinfection By-Products and Human Health, IWA Publishing. Each location is unique and requires thoughtful consideration of all of the options: Remember, pick the right tool for the right job

28 Data: Nitrosamine Occurrence Source: Seidel et al., EPA Stakeholders Meeting, 9/21/10

29 Extent of Detects WHO Guideline Value Health Canada Guideline Value CA Notification Level Source: Seidel et al., EPA Stakeholders Meeting, 9/21/10

30 UCMR2 Data Organized by Disinfectant Nitrosamines Occurrence in UCMR2, Organized by Disinfectant Number of Samples and "Hits" Nitrosamine Samples Collected Samples with Measured Nitrosamines Free Chlorine Chloramine Not Indicated No Disinfectant Other

31 Indeed, Nitrosamines Occur More Often in Chloraminated Systems 40.0% 35.0% Nitrosamines Occurrence Rate, Organized by Disinfectant 34.4% Occurrence Rate 30.0% 25.0% 20.0% 15.0% 10.0% 5.0% 0.0% 14.2% 2.7% 2.4% 3.1% Free Chlorine Chloramine Not Indicated No Disinfectant Other

32 Nitrosamine Occurrence is Not Evenly Distributed

33 Reckhow et al. (2016), WRF #4242 Examined DBPs formed with chlorine and/or chloramine at full scale and bench scale at 11 utilities Regulated and unregulated DBPs including N-DBPs and Br-DBPs

34 NDMA Found in Chlorinated and Chloraminated Waters Chlorinated Water Utility Chlorinated Highest Reported NDMA Chloraminated Water Utility Highest Reported NDMA #2 2.6 ng/l #8 <2 ng/l #4 3.3 ng/l #5 2.9 ng/l # ng/l Chloraminated #9 (+GAC) 11 ng/l #6 20 ng/l #7 21 ng/l # ng/l #3 No Data #1 (+GAC) No Data Points to the importance of site-specific investigation Source: Reckhow, D. A., C. Park, C. Wu, A. Bazilio, Y. Yu, V. Srinivasan, W. Mitch, and J. Skadsen Fate of Non-Regulated Disinfection By- Products in Distribution Systems. Project #4242. Denver, Colo.: Water Research Foundation.

DBP formation during chlorination and chloramination: Effect of reaction time, ph,

35 The Untrained Eye May Conclude that Chloramines Increase UTOX and DHAA Source: Hua, G., and D. Reckhow DBP formation during chlorination and chloramination: Effect of reaction time, ph, dosage, and temperature. Journal AWWA 100(8): American Water Works Association. Reprinted with permission. WaterRF (AwwaRF) Project 2755

However, Chloramine Provides and Overall Decrease in DBPs Free Cl 2 ClNH 2 μg/l μg/l TOX 878 106 UTOX 465 88 THM 203 2.

32 Chloramines provide an overall decrease, but site specific evaluations are important Source: Hua, G., and D. Reckhow. 2008.

36 However, Chloramine Provides and Overall Decrease in DBPs Free Cl 2 ClNH 2 μg/l μg/l TOX UTOX THM DHAN DCP TCP CP DHAA THAA Chloramines provide an overall decrease, but site specific evaluations are important Source: Hua, G., and D. Reckhow DBP formation during chlorination and chloramination: Effect of reaction time, ph, dosage, and temperature. Journal AWWA 100(8): American Water Works Association. Reprinted with permission.

37 Control of Chemistry is Key to Managing DBP Formation Free chlorine contact time before monochloramine formation limits: NDMA formation Cyanogen halide and Iodoacid formation Using breakpoint chlorination first provides better control of chloramine formation Manage ph to select monochloramine ph impacts NDMA, iodoacids, and other DBPs A site-specific evaluation and operational plan must consider these issues

38 On-Going Research Investigating Unintended Consequences of GAC WRF 4560 Hazen and Sawyer, USC, NCSU, CUBoulder, Corona Pilot and bench-scale findings further supported by recent publication Take -away: No one solution is perfect for every site

39 Nitrification: Can improper management of chloraminated systems can lead to nitrification?

ammonia Low chloramine residual Long detention times Increased temperatures

40 Nitrification Nitrification is a problem in Chloraminated Systems NH 3 + O 2 NO H + + 2e - NO 2- + H 2 O NO H + +2e - Contributing factors Excess ammonia Low chloramine residual Long detention times Increased temperatures Nitrosomonas, Nitrosococcus, Nitrosospira Nitrobacter, Nitrospina, itrococcus, Nitrospira

Nitrification Management Source: Adapted from Woolschlager, J.E., B.E. Rittmann, P. Piriou and B. Schwartz. 2001.

41 Nitrification Management Source: Adapted from Woolschlager, J.E., B.E. Rittmann, P. Piriou and B. Schwartz Developing an Effective Strategy to Control Nitrifier Growth Using the Comprehensive Disinfection and water Quality Model. In Proc. World Water and Environmental Resources Congress. Renton, Vir.: ASCE. Reprinted with permission from ASCE.

42 Nitrification Management Optimize Cl:NH3 ratio (approx. 4.5:1) Minimize free ammonia Increase chloramine residual Decrease detention time Flush, remove sediment Water temperature <25 o C Increase ph to Reduce organic carbon levels Improve corrosion control, iron removal Apply chlorite Flush with free chlorine

43 Other Health Effects: People have complained of skin rashes and asthma in chloraminated systems what do we know about this?

44 Citizen Activist Groups Have Reported Various Health Issues Associated with Chloramine Use Symptoms include mouth ulcers, persistent skin rashes, digestive issues including IBS and reflux, and respiratory ailments Symptoms are consistent with high dose exposure to both chlorine and chloramines There are no peer-reviewed (or other) publications to support this claim Complaints also common to chlorinated and chloraminated Systems Co-occurrence of underlying factors and pre-existing conditions make it difficult to determine a cause

distributed > 50,000 pamphlets outlining health effects related to

45 The Champlain Water District, VT Story Champlain Water District changed to chloramine in 2006 People Concerned about Chloramines (PCaC) distributed > 50,000 pamphlets outlining health effects related to chloramine use Weekly letters to the editor for ~ 5 years Example health effects cited:

46 CDC Investigation Found Wide-Spread Bias and Unreliable Results Champlain Water District is the largest water utility in Vermont (23,000 connections = 69,000 people) PCaC implemented massive 50,000+ pamphlet campaign against chloramines CDC was called in to investigate reported health effects

47 Swimmer s Asthma is Real, but Different than Drinking Water Exposure There are documented cases of swimmers having asthma-like symptoms from exposure to high concentrations of di- and tri-chloramine in pools It is entirely possible that there is a sensitive subset of the population that could react to chloramines But even with the high usage rate, we still have not seen any credible evidence one way or the other However, the same can be said for free chlorine

48 Lead Contamination Conversion from free chlorine to chloramine has occurred with increased lead levels is chloramination to blame?

49 Lead Chloramination increases lead exposure Reaction EH 0 (V) HOCl + 2e- + H+ Cl- + H2O 1.48 NH2Cl + H2O + 2e- Cl- + OH- + NH Source: Yanjiao Xie Dissertation: Dissolution, Formation, and Transformation of the Lead Corrosion Product PbO 2 : Rates and Mechanisms of Reactions that Control Lead Release in Drinking Water Distribution Systems. Washington University, St. Louis.

50 Passivation Is the Key for Most Utilities Passivation is the formation of lead and copper carbonate films calcium carbonate film metal oxide film metal carbonate film phosphate/metal/carbonate film water Pipe wall Film formation prevents galvanic cell reaction

51 When Chemistry Changes, Reversal of Passivation Can Occur For DC Water, switching to chloramine from chlorine without corrosion inhibitor initiated release of Pb In Flint, MI, the water supply (chemistry) changed but free chlorine was the disinfectant water Pipe wall Film dissolution leads to corrosion and Pb/Cu release

52 Many Factors Can Impact Metal Temperature ph & stability (buffering) ORP/corrosion potential Release from Pipes Type and amount of disinfectant Dissolved oxygen Alkalinity/DIC Orthophosphate Polyphosphate (amount and type) Chloride Sulfate Surfaces downstream of LSLs (i.e. galvanized interior pipe) Iron (deposition and corrosion) Calcium Manganese Aluminum NOM (type, amount) Amount of mixing of WTPs or sources Ammonia Hydrogen Sulfide Silica Microbial activity (nitrification and other) Michael Schock: Simultaneous Compliance: Myth versus Reality 52

53 Lead Corrosion is All About Water Chemistry Disinfectant selection is not inherently the cause of lead corrosion, but can be a factor Any changes in treatment, including disinfectant changes, should be evaluated for potential impact to lead and copper corrosion Active corrosion control strategies should be a part of any changes to water chemistry and treatment

54 Chloramine Use and Fish Kills: Water main breaks with chloraminated water have resulted in fish kills will this happen in my community?

Water Mains, Chloramine Use, and Fish Kills Chlorine and chloramines are toxic to fish Chloramines will bind to hemoglobin, preventing oxygen transport In fish this occurs through

55 Water Mains, Chloramine Use, and Fish Kills Chlorine and chloramines are toxic to fish Chloramines will bind to hemoglobin, preventing oxygen transport In fish this occurs through the gills and has resulted in fish kills in home aquariums and in the environment

56 Water Mains, Chloramine Use, and Fish Kills WRF survey indicates 0.25 water main breaks per mile per year Large cities hundreds of breaks per year Fish kills remain relatively rare, though they do occur Managing risks and rapid response are key

57 Impact of Chloramine Use on Elastomers and Premise Plumbing

58 Impact of Chloramine Use on Elastomers and Premise Plumbing AwwaRF Study Chloramine Effects on Distribution System Materials (1993) Used very high concentrations of chlorine and monochloramine Some elastomers did have higher degradation during chloramination BUT, others also degraded under free chlorine Potential customer complaints: black flecks in water May be due to gasket/washer degradation Recommend replacing with chloramines-compatible material

59 Elastomers Elastomer Name No. of years to reach 50% weight change EPDM-P >30 EPDM-S 21.9 Nitrile 3.9 SBR 2.3 Natural Rubber 1.9 Neoprene 0.4 EPDM, ethylene propylene diene monomer; -P peroxide cures, -S sulfur cured; SBR, styrene butadiene rubber WRF 91197: Overall, EPDM-P performed significantly better than any of the other elastomers exposed to chlorine and chloramine disinfectants Source: Rockaway, T. D., G. A. Willing, R. M. Schreck, and K. R. Davis Performance of Elastomeric Components in Contact With Potable Water. Project # Denver, Colo.: Water Research Foundation and American Water Works Association; London, UK: IWA Publishing.

60 Commercial Products Kohler manual flushometer American Standard American Standard commercial Kohler toilet All advertise use of chlorine and chloramine resistant NPDM materials American Standard

61 Concluding Thoughts

62 Multiple Disinfectants Are Available in the Toolbox Each with Unique Risks and Benefits Chlorine Fast-acting on most pathogens Residual remains in distribution system Forms many halogenated DBPs and nitrogenous (N) DBPs Less effective at penetrating biofilms Chloramine Residual remains in distribution system Forms fewer DBPs than chlorine Associated with some N-DBPs & I-DBPs; need to manage risk More effective at penetrating biofilms Nitrification is a risk and must be managed

63 Concluding Thoughts Disinfectants are not universal and none are without tradeoffs Regardless of the disinfectant, operations teams need to know the chemistry and latest research Tools are available for proper use and management of disinfection Guidance available for responding to citizen questions and concerns 63

64 WRF Resources Conversion to Chloramine and Process Optmization Optimizing Chloramine Treatment: Second Edition (project # 2760) A Guide for the Implementation and Use of Chloramines (project # 2847) Long-Term Effects of Disinfection Changes on Water Quality (project # 2940) Nitrification Chloramine Decomposition in Distribution System and Model Waters (project # 937) Ammonia from Chloramine Decay: Effects on Distribution System Nitrification (project #553) Lead and Copper Leaching Effect of Changing Disinfectants on Distribution System Lead and Copper Release (project #3107) The Role of Free Chlorine, Chloramines, and Natural Organic Matter in the Release of Lead into Drinking Water (project # 3172) 64

65 WRF Resources Disinfection By-Products Quantifying Hydrazine in Chloraminated Water (project #4141) Formation of Hydrazine as a Chloramine By-Product (project #2997) Controlling the Formation of Nitrosamines During Water Treatment (project # 4370) Elastomeric Material Degradation Performance of Elastomeric Components in Contact with Potable Water (project #2932)

66 Thank You Comments or questions, please contact: For more information visit:

Disinfection Overview

1 Disinfection Overview Module 3 2 Learning Objectives Be able to discuss the purpose and types of disinfection Be able to discuss the basics of chlorination and chloramination 3 Topics to be Covered Why