The Stage 2 D/DBPR and LT2ESWTR--Where are We Going

1. The Stage 2 D/DBPR and LT2ESWTR--Where are We Going J. Alan Roberson, P.E. Director of Regulatory Affairs AWWA-Washington, DC

2. Outline • Overview of the M/DBP Cluster • Overview of IESWTR and Stage 1 D/DBPR • Preliminary ICR Data Analysis • Where the LT2ESWTR and Stage 2 D/DBPR May Be Going

3. Microbial/Disinfection By-Products (M/DBP) Cluster • Balancing of acute microbial risks with chronic chemical risk a unique regulatory challenge • EPA used negotiative processes instead of traditional proposal and public comment • ‘92 & ‘93 negotiated rulemaking (Reg-Neg) led to ‘94 proposals for ICR, Stage 1 D/DBPR , & IESWTR • ICR data would be used for selection of IESWTR option • ICR delayed due to multiple problems • ICR monitoring started in July, 1997 instead of October, 1994 • Led to ‘97 Federal Advisory Committee (FACA)

4. 1997 Federal Advisory Committee (FACA) Process • Looked at components of ‘94 proposals • What can we use to meet statutory deadlines? • FACA met through March-July, 1997 • Agreement in Principle signed in July, 1997 • Notice of Data Availability published in Federal Register on March 31, 1998 • IESWTR focused on new turbidity standards • Profiling/benchmarking provisions • Minor changes to Stage 1 D/DBPR

5. The First Regulations in the M/DBP Cluster • Stage 1 D/DBPR & IESWTR published in the Federal Register on Dec. 16, 1998 • New MCLs and treatment techniques • Optimizing existing treatment rather than major shifts to alternative technologies • Costs not insignificant--$1 Billion/year • Compliance in 2001 & 2003 • LT1ESWTR for systems <10,000 people • Final in 2000 and compliance in 2003

6. Stage 1 D/DBPR • Lowers existing MCL for TTHM from 0.10 mg/l (100 ug/l) to 0.080 mg/l (80 ug/l) • Applies to all systems (except for transients) • Phased compliance for small systems • Establishes new MCLs • HAA5--0.060 mg/l (60 ug/l) • MCAA, DCAA, TCAA, MBAA, DBAA • Chlorite--1.0 mg/l • Bromate--0.010 mg/l (10 ug/l)

7. Stage 1 D/DBPR (cont.) • Establishes Maximum Residual Disinfectants Levels (MRDLs) for common disinfectants • Chlorine & chloramine--4.0 mg/l (as Cl2) • Chlorine Dioxide--0.8 mg/l (as ClO2) • Daily monitoring for chlorine dioxide & transients • MRDLs can be exceeded for short periods • Enhanced coagulation and softening treatment technique for TOC removal • Step 1 matrix & Step 2 process (with “outs”)

8. IESWTR • Surface water systems serving >10,000 people • 2 logs Cryptosporidium removal credit for conventional treatment • Lowered combined filter turbidity • From <0.5 NTU to <0.3 NTU 95% of the time • From <5 NTU to <1 NTU as a maximum • Monitor treatment processes carefully • Compliance still based on 4-hr. intervals

9. IESWTR (cont.) • Individual filter turbidimeters • Readings every fifteen minutes • Exceptions reported to state when: • >1.0 NTU for any 2 15-min. readings or >0.5 NTU for any 2 readings after 1st 4 hours • Develop filter profile within 7 days • Self-assessment for >1.0 NTU for 2 15-min. readings at any time in 3 consecutive months • Comprehensive Performance Evaluation for >1.0 NTU in 2 consecutive months

10. IESWTR (cont.) • Profiling & Benchmarking • TTHM >0.064 mg/l or HAA5>0.048 mg/l • Develop profile-daily inactivation for one year based on daily measurements of operational data • Calculate benchmark & consult with State • Lowest monthly average inactivation • Cover new finished water reservoirs • Sanitary survey requirements

11. Information Collection Rule • DBP and microbial monitoring data to be used for the Stage 2 D/DBPR & LT2ESWTR • 18 months of data from the systems serving >100,000 people--296 utilities--501 plants • July, 1997 to December, 1998 • Data is currently being analyzed • A lot more work than initially thought • Bench- and pilot-scale treatment studies for systems with high levels of DBP precursors

12. ICR Data Analysis Tools • ICRFED--the very large Federal database for all monitoring & engineering data • Auxiliary databases developed for more relevant data (Access-based) • Available on CD from EPA • Stage 1 baseline & Stage 2 options • Surface Water Analytical Tool (SWAT) • Results extrapolated for medium & small systems • Expert panel for large groundwater systems

13. Aux 1 - Primary Auxiliary Database Utility and Plant Level Data Sampling Results Data Treatment Operation Data Auxiliary Database Relationships Query Tool Aux 2 CT & Disinfectant Decay Aux 4 Sludge Production . Aux 6 Distribution System DBPs Aux 8 Model Interface/ Database Aux 3 Enhanced Coagulation Aux 5 Washwater Return

14. Model Outputs Model Inputs Aux1 Graphical User Interface (GUI) SWAT/ Model Aux8 Selection Criteria Surface Water Analysis Tool Data Process Overview

15. Final Large Surface Water Stage 1 Baseline Technology Cost Levels

16. Historical Comparison of TTHM Cumul. Freq. Distributions • AWWARF Survey 1984-86 • 727 utilities • NOMS--1976-77 • 450 utilities • NORS--1975 • 490 utilities • ICR--three quarters of data • 469 plants; 1002 quarterly averages

18. Stage 1 Baseline TTHM Levels

19. Stage 1 Baseline HAA5 Levels

20. TTHM v. HAA5 Plot--Stage 1 Baseline--Running Annual Averages

21. TTHM v. HAA5 Plot--Stage 1 Baseline--Single Highest

22. TTHM v. HAA5--ICR Maximum Values Based on 4 Quarters

23. Microbial Monitoring • Source water monitoring • Giardia, Cryptosporidium, viruses, & coliforms • Virus monitoring “out” • Finished water monitoring • Giardia & Cryptosporidium monitoring based on triggers in source water monitoring • Not many plants monitored finished water • Handful of detects in finished water

24. Microbial Monitoring (cont.) • Cryptosporidium results (total) • 93% non-detects • Higher detections in flowing streams versus reservoirs • Supplemental survey results--higher detectsions • Giardia results (total) • 82 % non-detects • Similar higher detections in flowing streams • Virus results--77% non-detects

25. Cryptosporidium ResultsPercentage Non-Detects--18 Months ICR Data

26. Stage 2 D/DBPR & LT2ESWTR • Part of the ‘92-’93 Reg-Neg agreement • EPA committed to meeting their deadlines • How far do we need to go beyond the Stage 1 D/DBPR & IESWTR? • Negotiations April, 1999-July, 2000 • New health effects data & ICR data will be a key part of the negotiations • Proposal in early 2001 • Final in May, 2002

27. The Possible Future for the Stage 2 D/DBPR & LT2ESWTR • Major changes to the Stage 1 rules • Single Maximums • Cryptosporidium inactivation requirement • Inactivation based on additional monitoring? • 1 log additional for systems on flowing streams • Minor changes to the Stage 1 rules • Shaving peak DBP levels • Distribution systems?? • States requirement for cross-connection controls

28. Potential Stage 2 D/DBPR & LT2ESWTR Options • DBP options • 80/60 annual average of the maximum • Similar to location running annual average • Single max.--80/60 & 40/30 as MCLs and 120/90 as an Action Level (combinations?) • Bromate at either 10 ppb or 5 ppb • Cryptosporidium inactivation • 0, 0.5 log, and 2.0 log requirement • Ultraviolet (UV) light treatment on and off

29. The Revised Matrix--41 SWAT Runs

30. Comparison of RAA, LRAA and AAM from ICR TTHM Data--Cl2 Plants

31. Comparison of RAA, LRAA and AAM from ICR TTHM Data--CLM Plants

32. RAA EquivalenciesBased on ICR plant data

33. 80/60 RAA EquivalenciesBased on ICR plant data

34. Elements of Potential Microbial Framework • Treatment Characterization • Characterize source water • Determine whether additional Cryptosporidium monitoring is necessary • Monitoring criteria for estimating mean Cryptosporidium concentrations in source water • Criteria for classifying potential exposure • Using mean Cryptosporidium concentration and treatment characterization for plant • Criteria for mitigating potential exposure • Based on watershed and/or treatment control measures

35. Treatment Characterization • Characterize existing treatment • Compare to toolbox • Determine if adequate and whether further action is necessary. (see toolbox)

36. Characterize Source Water - Determine if Cryptosporidium monitoring is needed • Use one or more of following: fecal coliform, E.coli , Total coliform, turbidity, as indicator(s) of challenged watershed, and/or watershed characteristics (a watershed index) • If indicator(s) (possibly a mean value) is below a critical level, system would be below Crypto occurrence level of concern • Acceptable misclassification rates a major issue

37. Vulnerability Index Correct Incorrect of Concern Protective

38. Characterize Source Water - Monitoring Criteria for Estimating Means • Suggested conditions: 24 monthly samples (2 years)), at least 10L/sample, 40% mean recovery, 50% CV, approximately $500./sample) • Concerns: high costs (utilities and states), method is not approved, interpretation of results, high burden on small systems, does not measure infective Crypto, not necessarily capturing peak events • Benefits: most direct way of determining relative levels of Crypto in the sourcewater

39. Characterize Source Water - Monitoring Criteria for Estimating Means • Plants that must monitor would monitor monthly for Cryptosporidium in source water at intake of each plant • Method 1623 (or equivalent) by approved labs • At the end of 2 years, systems would calculate • option 1: mean value • option 2: highest running annual mean • Systems would use mean concentration of each plant to classify potential exposure

40. Classifying Potential CategoriesDistinguish relative amounts of Cryptosporidium in source water Plant Highest Running Action to Reduce Category Annual Mean Exposure A < 0.01/L No Action B > 0.01/L to < 0.1/L No Action/“Toolbox ” C >0.1/L to < 1.0/L “Toolbox” D >1.0/L “Toolbox ”

41. Treatment Toolbox Options Challenges = (1) assigning category shift values and (2) implementation transaction costs for utilities and States

42. Total Annualized Costs-- Medium & Large SW Systems

43. Capital Costs -- Medium & Large SW Systems

44. Household Costs -- Medium & Large SW Systems

45. Conclusions • EPA is going to propose a rule in early 2001 • FACA will have to scramble to complete their negotiations by July, 2000 • Most everyone has some concern about high single DBP values • Most everyone has some concern about systems “vulnerable” to microbial contamination