EPA Review of TCR and Distribution System Issues

1. EPA Review of TCR and Distribution System Issues Kenneth H. Rotert US EPA Office of Ground Water and Drinking Water ASDWA Annual Conference October 25, 2001

2. Overview • Background • Public Health Concerns • Activities to Date: TCR • Activities to Date: Distribution System Issues • Upcoming Activities

3. Background • TCR Review and Revisions Required in SDWA • “not less often than every 6 years, review and revise, as appropriate, each NPDWR…” • TCR Promulgated in 1989 • M/DBP FACA Agreement (Sept. 2000) • Evaluate Available Data and Research on Aspects of Distribution Systems that may Create Risks to Public Health • Work with Stakeholders to: • Initiate a process for addressing cross connection control and backflow prevention requirements • Consider additional distribution system requirements related to significant health risks

4. Public Health Concerns • Outbreaks Related to Distribution Systems • 66 Distribution System Outbreaks Between 1981-1998 • 64% of distribution system outbreaks (42) in CWSs • 21% of distribution system outbreaks (14) in NCWSs • 18% of Outbreaks 1981-1998 • Contaminants in Distribution System Outbreaks (CDC Data) • Chemical Outbreaks with 100 or More Ill or at Least One Death • Copper - 9 outbreaks/125 ill • Ethylene Glycol - 2 outbreaks/30 ill/1 death • Microbial Outbreaks with 100 or More Ill or at Least One Death • Campylobacter species - 4 outbreaks/513 ill • Norwalk virus - 2 outbreaks/225 ill • Salmonella species - 4 outbreaks/1496 ill • Giardia species - 10 outbreaks/2034 ill • AGI - 16 outbreaks/1975 ill • Shigella species - 4 outbreaks/118 ill • E. coli - 1 outbreak/243 ill/4 deaths • SRSV - 1 outbreak/148 ill

5. Activities to Date: TCR Review • Notice of Intent - Six-Year Review • NOI Being Published Along with Six-Year Review of Chemical Contaminants • Regulatory Review and Development Being Carried Out on Separate Track • Comments Received on TCR • Unsolicited Comments Reviewed • Received since 1989 promulgation date • Solicited Comments January, 2001 • Comments solicited from EPA Regions, States, ASDWA, AWWA, AMWA, NRWA and ASM • Total 66 Letters, 827 Comments

6. Activities to Date: TCR Review • Routine Monitoring Comments • Increase Minimum to Greater than One Sample Per Year • Base Sampling Frequency on Risk (Cross connections, SWAP) • Waive TC Monitoring if Undisinfected, no Distribution System • Increase Requirements if MCL or Monitoring Violation • Use TC as an Initial Screen with E. coli Follow-Up • Statistically Determine Number of Monthly Samples Required • Review Monitoring Requirements through Stakeholder Process • Follow-up Monitoring Comments • Drop Fecal Coliforms, Keep E. coli • Drop Five Routine Samples Following Month • More Flexible Location for Fourth Repeat Sample • Clarify Repeats in Systems w/o Distribution System • Better Ways Exist to Determine Plumbing Problem

7. Activities to Date: TCR Review • MCL Comments • Drop MCL for TC, Keep for E. coli • Change to Action Level • Site Sampling Plan Comments • Greater Flexibility - Emphasize Monitoring Critical/Vulnerable Sites • Allow for Dedicated Sampling Taps • Concern over Sampling Consumer Taps • Violation and Reporting Comments • Reduce Number of Monitoring and Reporting Violations • Streamline and Simplify Reporting • Definitions Comments • Re-examine Definitions for MCLs/MCLGs • Add/Refine Definitions - Violations, Compliance and PWS

8. Activities to Date: Distribution Systems • Expert Panel Convened June 2000 • Attendees - OGWDW, ORD, Academia, Utility Personnel, AWWSCo., Consultants, State Regulators • Discussed Health Risks Associated with Various Distribution System Issues • Agreed on the Preparation of White Papers on Issues Ranked of Significant Health Risk Concern • White Paper Purpose • Characterize Health Risks Associated with Distribution System Issues and Potential Solutions for Reducing the Risks • Use as an Informational Source for Regulatory Development

9. Activities to Date: Distribution System White Papers • White Papers Status • First Drafts Prepared • Cross Connection Control - (EPA) - Being revised • Biofilms/Regrowth - (EPA) - Finalizing first draft • First Drafts Under Preparation • Intrusion - (AWWSCo) • Aging Infrastructure - (AWWSCo) • Covered Storage - (AWWA) • Decay in Water Quality over Time - (AWWA) • Corrosion, Permeation and Leaching - (AWWA) • Contamination Following Repair/Replacement - (AWWA) • Nitrification - (AWWA) • Additional Issues?

10. Cross Connection Control • Cross Connections Can Lead to Backflow of Chemical or Microbial Contaminants • Where Uncorrected, Cross Connections Can Result in Long-Term Exposures. • Estimated 90% of backflow events unreported • 26 Cross connection related outbreaks from 1981-1998 reported to CDC • EPA Draft Cross Connection White Paper (October, 1999) • 448 Backflow Events 1970-1999 • 124 Events Reported Illness - Estimated 11,854 Cases and 13 Deaths • Common Contaminants • Blue/green water - 34 incidents • Ethylene glycol/antifreeze - 18 incidents • Chromium species - 18 incidents • Chlordane - 11incidents • Giardia - 10 incidents • Common Elements Being Examined

11. Biofilms/Regrowth • Several Pathways Through Which Microbes can Enter Distribution System • Microbes can Become Entrained in Biofilm • Some Organisms can Grow or Recover in Biofilm • Some Measure of Protection from Disinfectants Provided • Pressure Changes or Erosion Can Release Contaminants • May Interfere with the Utility of Indicator Organisms • Many Control Methods or Approaches Exist • Some Pathogens of Concern in Biofilms • Legionella • Mycobacterium Avium Complex • Helicobacter (?)

12. Intrusion • Contaminants Can Enter When Pressure Drops • Leak Sites Become a Portal for Contaminant Intrusion • Well-Run Systems Average 10-20% Leakage • Common Causes of Pressure Drops • Pump Operation • Flushing Operations • Opening/Closing Hydrants • Changes in Demand • Main Breaks • Valve Operation • Power Failures • Significance of Intrusion • AWWARF Pathogen Intrusion Study (Kirmeyer et al., 2001) • Most sites had significant pressure drops • Water samples exterior to pipe - 42.8% fecal coliform, 12.5% enteric virus positive

13. Aging Infrastructure • The Aging of Distribution System Infrastructure • Average Pipe Age 21-91 Years • Oldest Sections 35-140 Years • Pipes Older than 20 Years: 42.53 - 69.57% • Current Replacement Rates 0.5% Annually • Shortened Economic Lives of Materials • Multiple Generations of Infrastructure to Wear Out at Nearly the Same Time • Life Varies Depending on the Materials • Effects of Aging Infrastructure • Leakage and main breaks • Intrusion • Backflow • Enhanced Biofilm Development • Enhanced Corrosion • Water Quality Decay

14. Covered Storage • Contaminants May Be Associated with Sediments • Coliforms • Inorganics (e.g., Radium) • Humans or Animals can Enter and Contaminate • Some Drowning have been Documented • Trash Disposal • Storage Time is a Concern • Klebsiella (Fecal Coliform) is a Concern in Redwood Tanks • Outbreaks Caused Associated with Covered Storage Vessels • Salmonella typhimurium Outbreak in Gideon, Mo. • Over 400 cases of illness and seven deaths • Caused by bird feces contaminating an elevated storage tank

15. Decay in Water Quality over Time • Problems Associated with Excess Residence Times • Formation of Disinfection and Corrosion Byproducts • Enhances Proliferation of Microbes • Loss of Disinfectant Residual • Can Accumulate Contaminants for Later Release • Inorganics • Taste, Color and Odor Problems • Causes of Excess Residence Time • Improperly Sized Distribution Systems • Low Flow Areas (e.g., Dead Ends) • High Demand Storage • Lack of Valve Exercise

16. Corrosion/Permeation/Leaching • Corrosion • Causes Include Water Chemistry, Electric Grounding and Microbially-Induced • Possible Solutions Include Use of Newer Pipe Materials and Corrosion Control • More Understanding Needed on the Effects of Changing Chemical Treatment • Permeation • Causes Include Plastic Pipes in Close Proximity to Gas Tanks (VOCs) and Runoff • Possible Solutions Include Pipe Placement and the Use of Compatible Pipe Materials • Leaching • Linings (Including Asphalts with High VOCs), Improperly Cured Pipe Materials • Current Research Exploring the Potential of Leaching of Endocrine Disruptors (Include Phthalates, Bisphenols, Alkyl Phenols, Alkyl Phenol Ethoxylates and Polyethoxylates)

17. Contamination Following Repair/Replacement • Improper Repair or Replacement Procedures • Lack of Standardized Procedures • Need to Return to Service ASAP • Lack of Proper Flushing and Disinfection • Effects of Improper Repair and Replacement • Microbial and/or Chemical Contaminants Introduced • Problems Associated with Large Releases of Chlorine • Dermal allergies • Accelerated corrosion • Customer complaints • Some Potential Solutions • Licensed Operators • Supervisor Oversight • Replacement Policy and/or Program

18. Nitrification • May be a Chloramine Issue When Excess Ammonia Added • Added Ammonia May Act as a Nitrogen Source for Nitrifying Bacteria • Also an Issue Related to Naturally-Occurring Ammonia and Other Reduced Nitrogen Compounds • Possible Effects of Excess Nitrogen Source in Distribution System • Proliferation of Some Bacteria Where Nitrogen is Growth-Limiting Nutrient • Increased Health Effects Potential • Methemoglobinemia • State of Science on Nitrification Due to Chloramine Formation May Warrant Additional Information

19. Upcoming Activities • Complete White Paper Development • Target Date - February/March, 2002 • Work with Partners to Complete • Circulate to Interested Co-Regulators and Stakeholders • Begin Evaluating Potential Distribution System Solutions/Requirements • Work with Co-Regulators and Stakeholders to Identify High Priority Issues to be Addressed Through Regulatory Development

20. Contact Information Kenneth H. Rotert US EPA 1200 Pennsylvania Avenue, NW, Mail Code 4607 Washington, DC 20460 E-mail: rotert.kenneth@epa.gov Phone: 202-260-5748