talking about chloramines: a discussion of the concerns
TRANSCRIPT
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Talking about Chloramines A Discussion of the Concerns and Questions Regarding Water
Treatment
September 15 2016
copy 2016 Water Research Foundation ALL RIGHTS RESERVEDcopy 2016 Water Research Foundation ALL RIGHTS RESERVED
Ben Stanford PhDDirector of Applied Research
Hazen and Sawyer
and
Mark LeChevallier PhDVice President Chief Environmental Officer
American Water
copy 2016 Water Research Foundation ALL RIGHTS RESERVEDcopy 2016 Water Research Foundation ALL RIGHTS RESERVED
Objective
To provide a balanced overview of the scientific evidence about chloramine use including disinfection by-products health concerns environmental concerns and infrastructure concerns
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
WRF ResourcesConversion to Chloramine and Process Optmization
bull Optimizing Chloramine Treatment Second Edition (project 2760)bull A Guide for the Implementation and Use of Chloramines (project 2847)bull Long-Term Effects of Disinfection Changes on Water Quality (project 2940)
Nitrification
bull Chloramine Decomposition in Distribution System and Model Waters (project 937)bull Ammonia from Chloramine Decay Effects on Distribution System Nitrification
(project 553)
Lead and Copper Leaching
bull Effect of Changing Disinfectants on Distribution System Lead and Copper Release (project 3107)
bull The Role of Free Chlorine Chloramines and Natural Organic Matter in the Release of Lead into Drinking Water (project 3172)
4
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
WRF Resources
Disinfection By-Products
bull Quantifying Hydrazine in Chloraminated Water (project 4141)bull Formation of Hydrazine as a Chloramine By-Product (project
2997)bull Controlling the Formation of Nitrosamines During Water
Treatment (project 4370)
Elastomeric Material Degradation
bull Performance of Elastomeric Components in Contact with Potable Water (project 2932)
copy 2016 Water Research Foundation ALL RIGHTS RESERVEDcopy 2016 Water Research Foundation ALL RIGHTS RESERVED
Agenda
bull Framing the Issue A Heated Debatebull Disinfection Compliance DBPs
bull Discussion of Specific Concernsbull From DBPs and Rashes to Pipes and Fish
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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 cityrsquos plan for chloramine disinfection- KRBD (AK) February 5 2014
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
A Long History of Chloramine usebull First full-scale free chlorine use in Chicago
bull First use of chloramine in Denver for TampO Control
bull 16 usage rate in the United States
bull Need for ammonia during WWII decreased availability for H2O disinfection and use declined over next few decades
bull Organic DBPs ldquodiscoveredrdquo ndash J J Rook
bull MCL for TTHM set at 100 μgL
bull 18 of systems using chloramine primarily for regulatory compliance
bull MCL for THMs set at 80 μgL HAA5 set at 60 μgL
bull US chloramines use estimated at gt30
1908
1917
1930s
1940s
1970s1979
1987
2002
2006
Adapted from M McGuire 2001
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
45 of US Population Is Served by Public Water Supplies Using Chloramine
536449
16
Percent of US Population on Public Water Supply Using Chloraminated Water
Using Free Chlorine Using Chloramine Unclassified
Data Courtesy of Chad Seidel Corona Environmental ConsultingAnalysis of EPA UCMR3 Data
Equates to around 30 of Public Water Supply Systems
100000000 people in United States use chloraminated water
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
Above All Public Health Protection is the 1 Priority
bull We must achieve public health protection in a fiscally and environmentally responsible mannermdashMany tools will get us to our goals
bull As scientists and engineers we evaluate options at each locationmdashIncludes a thorough evaluation of risks and
benefitsbull Free chlorine and chloramine are not
interchangeablemdashBoth require different approaches to managing
water quality
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
Utilities constantly balance multiple compliance objectives to protect public
health
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
With Nearly Half of Public Water Supplies on Chloramine Is There a Concern
bull Long history of chloramine usebull A significant portion of US cities
including those with major schools of public health pharmaceutical industries and foodbeverage production centers use chloramine
bull But there ARE real issues and concerns that must be taken into considerationmdashChloramine is not a universal solution
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
Todayrsquos Goal Discuss Topics That Have Been Raised Regarding Chloramine Use
Topics of DiscussionConcerned 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 systemsmdashwhat do we know about this
Lead Contamination Conversion from free chlorine to chloramine has occurred with increased lead levelsmdashis chloramination to blame
Fish Kills Water main breaks with chloraminated water have resulted in fish killsmdashwill this happen in my community
Premise Plumbing Monochloramine can attack rubber gaskets and flapper valves in toiletsmdashwill our plumbing system fail
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Discussion of Specific Topics Related to Chloramine Use
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
DisinfectionldquoChloramines are a weak disinfectantrdquo
Free chlorine is preferred over chloramines as a primary disinfectant
Source Adapted from LeChevallier M W C D Cawthon and R G Lee 1988 Inactivation of biofilm bacteria Copyright copy American Society for Microbiology Applied and Environmental Microbiology 54(10) 2492-2499
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
System AOC Level(ugL)
Samples Positive
Avg Coliform100 mL
Free Chlorinated 120 - 189 124 1077
Systems N=11 50 - 93 068 0058
Chloraminated 101 - 166 087 0022
Systems N=11 42 - 99 036 0015
Free chlorinated systems with high AOC had 87 higher occurrence rate and bacterial levels 19 t imes higher than low AOC systemsChloraminated systems with high or low AOC were not stat ist ically different
16
Source LeChevallier M W N J Welch and D B Smith 1996 Full-scale studies of factors related to coliform regrowth in drinking water Copyright copy American Society for Microbiology Applied and Environmental Microbiology 62(7) 2201-2211
Relationship between Disinfection and AOC on Coliform Occurrences
At high AOC levels free chlorine systems had 42 more coliforms at densities 49 times higher than chloraminated systems
At lower AOC levels free chlorine systems had 89 more occurrence at 4 times higher levels
copy 2016 Water Research Foundation ALL RIGHTS RESERVED17
Iron Galvanized Copper PVC0
1
2
3
4
5
6
7
Dec
reas
e Lo
g V
iabl
e C
ount
(CFU
cm
sup2)
Free 1 mgLMono 1 mgLFree 4 mgLMono 4 mgL
Impact of Pipe Surface on Disinfection of Biofilm Bacteria
Source LeChevallier M W C D Lowry and R G Lee 1990 Disinfecting biofilms in a model distribution system Journal AWWA 82(7) 87-99 copy1990 American Water Works Association Reprinted with permission
copy 2016 Water Research Foundation ALL RIGHTS RESERVED18
copy 2016 Water Research Foundation ALL RIGHTS RESERVED19
copy 2016 Water Research Foundation ALL RIGHTS RESERVED20
Lessons from Real LifeSan Francisco CA
bull 53 buildingsbull Sampled 3 times pre- and post-conversion to chloramines bull Sampled hot water heater and four distal sitesbull Sampled swab and water from distal sitesbull Surveys collected data on building age height type and number of hot
water heatersbull pH temperature free or total Cl2 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 2006 Reducing Legionella colonization of water systems with monochloramine Emerg Infect Dis 12(4) 588-596 httpwwwncbinlmnihgovpmcarticlesPMC3294698
copy 2016 Water Research Foundation ALL RIGHTS RESERVED21
Round 1Heater 2 3 4 5 6 7 8 9
Round 2Heater 2 3 4 5 6 7 8 9
Round 3Heater 2 3 4 5 6 7 8 9
Round 4Heater 2 3 4 5 6 7 8 9
Round 5Heater 2 3 4 5 6 7 8 9
Round 6Heater 2 3 4 5 6 7 8 9
Free Chlorine Chloramine
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
Legionella and Amoebaebull Intracellular Legionella in Acanthamoeba
Amoeba Comandonia Echinamoeba Filamoeba Hartmannella Naegleria Paratetramitus Vahlkamfia Tetrahymena Dictyostelium
bull Legionella survive for months resistant to 50 mgL free chlorine for 18 hr
bull Coated with amoebal proteins
bull Increases virulence replication
bull Legionella-containing vacuoles expelled prior to encystation
bull Trophozoite stage sensitive to disinfectants(CT999 = 15 mg-minL)
22
Trophozoite
Cyst
copy 2016 Water Research Foundation ALL RIGHTS RESERVED
Trophozoite Concentration
23
Chloramines
Utility Trophs 25 C
Trophs 42 C
TX - 27 74 82FL - 30 59 73CA - 4 68 73FL - 31 36 60CA - 32 13 36AZ - 33 58 84
Data courtesy of WateReuse Research Foundation