Daniel B. Stephens, Ph.D.

Transcription

1 Analysis of Groundwater Monitoring Controversy at the Pavillion, Wyoming Natural Gas Field Daniel B. Stephens, Ph.D Multi-State Salinity Coalition Annual Salinity Summit Understanding the Opportunities and Challenges of Fracking in an Era of Water Supply Scarcity February 19, Las Vegas, Nevada

2 Pavillion, Wyoming EPA, 2011 Source: EPA, 2011 and Mason, et al., 2005

3 Groundwater Water table about 16 ft bgs Water wells most <500 ft, up to 800 ft deep Wind River Formation (Aquifer) Depth to 2400 ft bgs Interbedded sandstone and shale Fits SDWA Underground Source of Drinking Water TDS < 10,000 mg/l Gas production also in Wind River Formation Starting at about 1100 ft bgs Frack fluids injected into USDW; 1220 ft bgs

4 Co-located O&G and Water Wells 211 Active Gas Wells 30 P&A d Wells 20 Temporarily Closed Wells 33+ Surface Pits (drilling fluids, flowback water) Pavillion Source: US EPA, 2011

5 Water Concerns Identified by Land owner s 210 ft deep well has petroleum smell/taste Detects odor at 160 ft when drilling replacement well Methane gas blowout when developing the 550 ft deep well Encana investigates pits Only local impacts Initiates cleanup In this photo taken Nov. 8, 2007, John Fenton and others examine neighbor Louis Meeks water in Pavillion, Wyo. (AP/Photo/Casper Star-Tribune, Dustin Bleizeffer) Source: AP, 2007

6 EPA Region 8 In response to taste and odor complaint: Exercises investigative authority under CERCLA (Superfund) Initiates a site inspection (HRS) Sampled 37 residential 2 municipal wells

7 Phase 1 Sampling Findings Most wells sampled have no apparent health concerns 11 wells have insufficient data Potentially, a connection between the results and oil and gas production activities. Cannot pinpoint any specific source at this time Source: U.S. EPA, 2009

8 Expanded Site Investigation: Phase 2 Sampling In key areas from Phase 1 23 Wells (17 domestic) Source: EPA, 2010

9 Phase 2 Findings TPH in 17/19 drinking wells Low levels Thermogenic methane 4 pesticides Some inorganics at high levels-consistent w/ historic values Previous TICs confirmed: Adamantanes; 2BE-P Bacteria not a health concern May contribute to taste and odor issues

10 Phases 3,4 (Deep Monitor Wells)

11 600 ft Source: US EPA, 2011

12 EPA Issues Draft Report Dec. 8, data indicates likely impact to ground water that can be explained by hydraulic fracturing. Source: U.S. EPA, 2011

13 Main Basis for EPA Conclusion Two Sample Events in Two Deep Monitor Wells High ph High potassium and chloride IPA, glycols, TBA, 2BE, phenol BTEX, GRO, DRO Breakdown products: acetate, benzoic acid These chemicals are potentially associated with hydraulic fracturing operations, in general

14 Industry Response to EPA Report Two Sampling Events in Two Deep Monitor Wells High ph EPA used soda ash in drilling fluids; cement High potassium and chloride Some natural, some from cement Source: Stimulation Petrophysics, Consulting, LLC, 2012

15 Paint and Coatings May Affect Results Painted casing and cement basket Potential sources of chemicals detected 2-BE, associated with paint 2-BE in Phase 4 MW-1: ND, 12.9 g/l MW-2: ND, ND Source: API, 2013 (with permission)

16 Industry Response to EPA Report Two Sampling Events in Two Monitor Wells IPA, glycols, TBA, 2BE, phenol IPA, phenols: potential breakdown from natural organic matter; same for benzoic acid glycol in blanks, QA/QC (labs disagree), Sources other than HF: antifreeze spill; cement TBA is not in frack fluids used in Pavillion 2-BE in 1 of 8 samples; labs disagree of presence in sample split BTEX, GRO, DRO Naturally occurring

17 News Media Headlines

18 White House Informed 11/15/11 between Heather Zichal and Bob Sussman, EPA 12/6/11 between Heather Zichal and Bob Sussman, EPA 1/3/12 between Heather Zichal and Bob Perciasepe, EPA HZ: Last week you mentioned that Inhofe received a briefing. Are you also doing one for the WY delegation? BS: Let me check HZ: Sorry - but any update here? BS: We are issuing the draft Pavillion report on Thursday after completing extensive discussions with the State and company. Happy to provide more details HZ: Can we get some talking points on this asap? [Re: Greenwire: EPA lab report shows flaws in Wyo. water study] Bob Sussman: EPA Senior Policy Counsel Bob Perciasepe: EPA Deputy Administrator Source: U.S. White House.gov

19 Governor of Wyoming Response Source: State of Wyoming, 2011

20 Congress Briefed Source:

21 Phase 5: USGS Re-Sampling in butoxyethanol, was not identified in the TIC analyses of any of the environmental samples. No glycols were detected in any samples. Because of low yield...well MW02 was not sampled for this study... Source: Wright, et al., 2012

22 Concentrations Decline Over Time DL= 7.7 g/l DL= 8.4 g/l ph and TDS 2-BE and Glycols Source: Gradient 2013

23 June 2013: EPA Withdraws as Lead Organization While EPA stands behind its work and data, the agency recognizes the State of Wyoming s commitment for further investigation and efforts to provide clean water and does not plan to finalize or seek peer review of its draft Pavillion groundwater report released in December, Nor does the agency plan to rely upon the conclusions in the draft report. EPA Offers No Rebuttal to Technical Comments Source: U.S. EPA, 2013

24 Clearly Communicating Conclusions...the existing data at this time do not establish a definitive link between deep and shallow contamination of the aquifer the data indicates likely impact to ground water that can be explained by hydraulic fracturing. Source: U.S. EPA, 2011

25 Status Source of Taste and Odor Problem Unresolved USGS Offers No Conclusions State of Wyoming Led Investigation More sampling; with MCL-based thresholds Mechanical integrity testing Results starting to come out

26 Similar Investigations for HF impacts To Groundwater In The Future Require Understanding the potential significance of findings Setting clear objectives Baseline data to help avoid controversy Careful planning Stakeholder involvement and transparency High standards of care in data collection Rigorous peer review throughout process Especially before issuing a draft report

27 END

28 National Study 5 Case Studies Sans Pavillion Sans Dimock, Parker Co. HISA Designation Can subsurface fluids migrate to drinking water? Sample existing wells, springs, surface water Similar to Pavillion Source: U.S. EPA, 2012

29 EPA Recognizes Role of Baseline Data An alternate explanation provided and considered by EPA is that other residents in the Pavillion area have always had gas in their wells. Unfortunately, no baseline data exists to verify past levels of gas flux to the surface or domestic wells. Collection of baseline data prior to hydraulic fracturing is necessary to reduce investigative costs and to verify or refute impacts to ground water. Source: U.S. EPA, 2011

30 Governor of Wyoming Response...conclusions are not supported by available evidence. I am troubled by the EPA s dismissal of the practical concerns raised by the Wyoming Oil and Gas Conservation Commission (WOGCC), Wyoming Department of Environmental Quality (DEQ) and Encana... I appreciate the information you have shared to date, but I believe it falls short of full disclosure. The EPA s approach to the peer review process seems destined to create further tension between the State of Wyoming, EPA, industry and the people of Pavillion. Source: State of Wyoming, 2011