Likely Future Regulatory Implications in Arizona: Chromium VI and Carcinogenic VOCs

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1 Likely Future Regulatory Implications in Arizona: Chromium VI and Carcinogenic VOCs Chad Seidel, Ph.D., P.E. Manager of Water Technology Jacobs Engineering Group, Inc. Thursday, February 2, 2012

2 Overview Chromium VI What did we know back then? Current Regulatory Status USEPA California DPH What do we know now? Carcinogenic VOCs Current USEPA Direction Ongoing Occurrence Analysis 2

3 Remember Erin Brockovich? 3

4 What did we know back then? Drinking water regulations Total Chromium USEPA MCL = 100 ug/l California MCL = 50 ug/l Hexavalent Chromium No USEPA or state MCLs for Cr(VI) 4

5 Chromium Regulatory Status: Recent Timeline Sept. 30, 2010 USEPA IRIS Toxicological Review of Hexavalent Chromium (External Review Draft) Dec EWG Report Chromium-6 the Erin Brockovich Chemical Is Widespread in U.S. Tap Water: Tests find cancer-causing chemical in 89 percent of cities sampled Dec. 31, 2010 Jan. 11, 2011 Jul. 27, 2011 California OEHHA offered a revised draft PHG at 0.02 ug/l USEPA recommended sampling California OEHHA posted final PHG at ug/l

6 Chromium Regulatory Status: MCL Development Efforts USEPA 100 ug/l Total Cr MCL According to Administrator, likely to regulate Cr(VI) Regulatory process would take up to two years Completion of human health assessment study Ensuing public comment period Senators Boxer and Feinstein introduced Senate bill 79 which would require EPA to promulgate a hexavalent chromium standard within one year of legislation Won t pass, but adds pressure California DPH 50 ug/l Total Cr MCL DPH has statutory mandate to develop Cr(VI)-specific MCL 3-4 years for MCL development and rulemaking Seeking additional information to support process Analytical methods Occurrence Treatment performance and cost 6

7 Current USEPA Regulatory Activities Courtesy of Steve Via, AWWA Six-Year 2 (3/2010) Carcinogenic VOCs Proposal (2012?) Six-Year 3 Proposal (<3/2014) Carcinogenic VOCs Final (2015?) Six-Year 3 (3/2016) RTCR Final (Summer, 2012) RTCR Effective (Summer, 2015) UCMR3 Proposal (3/2011) UCMR3 Monitoring (1/ /2015) LT-LCR Proposal (Spring 2012) ClO 4 - Proposal (2/2013) LT-LCR Final (Spring 2014) ClO 4 - Final (2/2015) Round 2 LT2ESWTR Monitoring (4/2015 5/2021) CCL3 Final (10/2009) Reg Det 3 Proposal (<7/2012) Reg Det 3 Final (<7/2013) 1 CCL4 Proposal (<10/2013) CCL4 Final (<10/2014) 2017 Key Proposal no fill Final filled Uncertain cross hatched Unique color for related regulatory actions Proposed Rule(s) (<7/2015) 1 Final Rule(s) (<1/2017) 1 Note: As yet unassigned (fluoride, acrylamide, epichlorohydrin, total chromium / Cr(VI)) 7

8 USEPA Chromium Regulatory Timeline Courtesy of Steve Via, AWWA Federal SDWA Timeline (EPA has options for approaching a rulemaking) IRIS Review Final (<12/2011) current schedule Administrator s Discretion UCMR3 Monitoring (1/ /2015) < 4 year rule-making process (time to propose and finalize rule) Reg Det 3 Proposal (<7/2012) Reg Det 3 Final (<7/2013) 1 Proposed Rule(s) (<7/2015) 1 Final Rule(s) (<1/2017) 1 Six-Year 3 Notice (3/2016) <4 yr rulemaking process PHG Final (7/2011)?? 2017 California MCL Timeline NOTE : SDWA provides 3 years to come into compliance with a new standard and if approved by state 2 additional years for 8 capital improvements.

9 California DPH Regulatory Status Phase I: Pre-MCL activities Information gathering for analytical methods, occurrence, treatment, costs Phase II: Draft regulatory package development Cost:benefit analysis, draft reg text Phase III: Formal Regulatory Adoption Process Agency reviews, public comment, signature Adapted from Dave Mazzera, Ph.D., California DPH 9

10 California DPH Regulatory Status months to develop MCL and initiate formal rulemaking process gather & evaluate data; perform analyses draft regulations with stakeholder input months to complete formal rulemaking Internal & external review OAL review and public comment period(s) Response to comments, final OAL review & adoption Overall timeline estimate: 3-4 years to complete hexavalent chromium MCL Adapted from Dave Mazzera, Ph.D., California DPH 10

11 California DPH Regulatory Status Arsenic MCL Case History Arsenic PHG = 4 ng/l (ppt); Final in April 2004 Final arsenic MCL set at 10 μg/l (prior MCL 50 μg/l) USEPA MCL in effect January 2006 CA MCL in effect November 2008 Why is the MCL greater than the PHG? Technical feasibility: DLR at 2 ppb (lower boundary of MCL evaluation) Federal MCL at 10 μg/l (set upper boundary) Cost benefit analysis: 10 vs. 2 μg/l Minor incremental benefit Adapted from Dave Mazzera, Ph.D., California DPH 11

12 What do we know now? Health Impacts: Future 1: Cr(VI) is a credible carcinogenic risk at low environmentally derived oral exposures Information to support a Cr(VI) MCL (or revised Total Cr MCL) Analytical method Occurrence Treatment Future 2: Most recent risk assessments are flawed and Cr(VI) is not a credible carcinogenic risk at oral exposures at ng/l concentrations 12

13 What do we know now? Occurrence: Chromium occurs in drinking water sources across the U.S. Percent of utilities with detectable chromium increases as method detection limits are lowered Speciation trends by source water Surface water predominantly Cr(III) Groundwater predominantly Cr(VI) 13

14 WaterRF 4414 Chromium Occurrence: Datasets Considered Data Source WaterRF #2759 USEPA CDPH Database NCBOS 6YR2 UCMR Geographic 46 States and 2 41 States California Coverage Tribes Period of Record Source Water Sampled Total Chromium Data? Hexavalent Chromium Data? Raw Drinking Raw and Treated Drinking Water Water SW and Drinking Water SW and GW GW SW and GW Yes Yes Yes Yes No Yes 14

15 Comparison of Datasets for Total Cr: 75%ile Results by Entry Point 100% 90% Percentile 80% 70% 60% 50% 6YR2 (n=64,423) NCBOS (n=342) 6YR2 Bayesian (50th) CDPH Raw (n=13,691) CDPH Treated (n=575) Total Chromium (µg/l) 15

16 USEPA 6YR2 Total Cr: 75%ile by EP > 10 µg/l 5-10 µg/l 16

17 National Compliance Estimates: Percent of Systems with 75%ile > MCL MCL (µg/l) All Systems Groundwater Systems All <10K 10K- Surface Water Systems >50K All <10K 10K- >50K 50K 50K 6YR2 n 33,047 29,214 27,770 1, ,833 2, NCBOS

18 USEPA 6YR2 Total Cr: 75%ile by EP Total Chromium > 10 µg/l > 10 ug/l 55 - to 10 ug/l µg/l 18

19 Arizona Compliance Estimates: Percent of Systems with 75%ile > MCL MCL (µg/l) All Systems Groundwater Systems All <10K 10K- Surface Water Systems >50K All <10K 10K- 50K 50K 6YR2 n >50K

20 What do we know now? Treatment Performance Technology Strong-base Anion Exchange Weak-base Anion Exchange Reduction Coagulation Filtration Reverse Osmosis Other: Chemical Reductive Media Biological Treatment MCL (ug/l)

21 Carcinogenic VOCs: Current USEPA Direction Source: EPA Materials USEPA Stakeholder Meeting September 21,

22 Carcinogenic VOCs: Current USEPA Direction What s the latest? We expect to initiate regulatory efforts to begin addressing carcinogenic VOCs by the end of March Typically, it takes about 2 to 2.5 years to develop a proposed rule and about 2 years to promulgate a final rule. USEPA Basic Questions and Answers for the Drinking Water Strategy Contaminant Groups Effort cvoc Rule proposal in Fall

23 Carcinogenic VOCs: Current USEPA Direction What s the latest? Lower individual MCLs for both TCE and PCE Analytical method improvements Could be in the range of 0.5 to 1.0 ug/l Risk reduction based on cancer cases avoided Group MCL Simple summation of VOCs in group, perhaps 2 ug/l Must determine what is in or out Demonstrating risk reduction more difficult 23

24 Carcinogenic VOCs: Current USEPA Direction What s the latest? Likely candidates 1,2,3-trichloropropane 1,3-butadiene 1,1-dichloroethane Not likely candidates aniline nitrobenzene urethane oxirane, methyl- benzyl chloride -- Possible substitutes 1,1,1,2-tetrachloroethane 1,1,2,2-tetrachloroethane DBCP EDB 24

25 Ongoing Occurrence Analysis Objectives Discern occurrence and co-occurrence of carcinogenic VOCs First cut analysis using readily available data USEPA 6YR2 1,2-dichloroethane 1,2-dichloropropane Benzene Carbon Tetrachloride Dichloromethane Tetrachloroethylene (PCE) Trichloroethylene (TCE) Vinyl chloride California DPH 1,2-dichloroethane 1,2-dichloropropane Benzene Carbon Tetrachloride Dichloromethane Tetrachloroethylene (PCE) Trichloroethylene (TCE) Vinyl chloride Nitrobenzene 1,1-Dichloroethane 1,2,3-Trichloropropane 25

26 USEPA 6YR2 Counted detections for individual VOCs Counted detections with co-occuring TCE detections Chem. ID Record Count Detect Count % Detect TCE Co-Occur % TCE Co-Occur Chem. Name 1,2-Dichloroethane (Ethylene Dichloride) ,636 2, % % 1,2-Dichloropropane , % % Benzene ,503 1, % % Carbon Tetrachloride ,864 4, % % Dichloromethane (Methylene chloride) ,009 3, % % Tetrachloroethylene ,042 34, % % Trichloroethylene ,609 29, % NA NA Vinyl chloride , % % Total unique sample records: 335,018 Unique samples with detections: (15.8%) 26

27 EPA Six Year Review 2: Occurrence < 5 ug/l 100% 99% 98% Cumulative Probability (%) 97% 96% 95% 94% 93% 92% 91% 90% Dichloromethane (Methylene chloride) Vinyl chloride 1,2-Dichloroethane (Ethylene Dichloride) Carbon Tetrachloride 1,2-Dichloropropane Trichloroethylene Tetrachloroethylene Benzene VOC Concentration (ug/l)

28 EPA Six Year Review 2: TCE and PCE Co-Occurrence < 5 ug/l 5 4 TCE and PCE Detectable Co-Occurrence GW SW PCE (ug/l) TCE (ug/l) 28

29 USEPA 6YR2: Utility Impacts Queried data for maximum concentrations of individual VOCs by CWS Regulatory Constraint Number of CWS (n) Percent of CWS (%) All CWSs 33, % Current MCLs % Current MCLs + TCE and PCE < 1 ug/l Current MCLs + TCE and PCE < 0.5 ug/l % 1, % Sum8 < 2 ug/l 1, % Sum8 < 1 ug/l 1, % 29

30 Conclusions Both Cr(VI) and cvocs have implications for Arizona Regulatory development at USEPA and California DPH on different tracks Upcoming opportunities to provide input into processes In the meantime, keep focus on continued public health protection! 30

31 Questions? Chad Seidel, Ph.D., P.E. Office: Mobile: