The groundwater in Pavillion, WY, contains chemicals that are normally used in natural gas production practices, such as hydraulic fracturing (fracking), according to a draft report released by the Environmental Protection Agency (EPA) Thursday.
At the request of Pavillion residents in 2008, the EPA began investigating water quality concerns in private drinking water wells. Since then, the state of Wyoming, the community of Pavillion and the owner of the gas field, Encana Corp., have joined EPA to assess the water quality and identify potential sources of contamination. After meeting with the Wyoming Department of Environmental Quality, EPA began sampling drinking water wells in 2009; a second sampling took place last year (see Daily GPI, Sept. 3, 2010; Aug. 28, 2009).
For the purposes of the test, the EPA constructed two deep monitoring wells to sample water in the aquifer. The draft findings indicated that the groundwater in the aquifer contained compounds likely associated with fracking, the agency said. The EPA also retested private and public drinking water wells in the community and found the samples were consistent with chemicals identified in earlier EPA results released in 2010 and are generally below established health and safety standards.
An Encana spokesman contested the EPA findings.
"It's interesting, in their press release the EPA talks about compounds likely associated with gas production practices," Doug Hock, an Encana spokesman told NGI's Shale Daily. "They are hedging their bets. This is not a conclusion; this is a probability... and we don't think it is a very good one for a couple of reasons.
"First of all, the EPA tested domestic wells, and they found no indication of oil and gas impacts. The only substance that exceeded drinking water standards was a plasticizer, which is found in drinking water wells all over the world. Then they drilled two deep monitoring wells into a natural gas bearing zone and they found natural gas. That's not a surprise. Encana did not put those constituents there, nature did. So you've got drinking water wells not impacted by oil and gas and deep monitoring wells in a gas bearing zone with oil and gas constituents -- not really much of a conclusion there."
In addressing the EPA's discovery of some synthetic chemicals -- glycols and alcohols -- in the deep monitoring wells, Hock said it is just as likely that those chemicals were introduced in the sampling process the EPA used as that they have anything to do with oil and gas.
Wyoming Gov. Matt Mead on Thursday afternoon classified the draft study as "scientifically questionable," noting that more testing is needed.
"We believe that the draft study could have a critical impact on the energy industry and on the country so it is imperative that we not make conclusions based on only four data points," Mead said. "Those familiar with the scientific method recognize that it would not be appropriate to make a judgment without verifying all of the testing that has been done."
The EPA also pointed out its draft findings are "specific to Pavillion, where the fracturing is taking place in and below the drinking water aquifer and in close proximity to drinking water wells -- production conditions different from those in many other areas of the country."
Mead added that the study released by the EPA was based on data from two test wells, which were drilled deeper than drinking water wells. He noted that the data from the test wells was not available to the rest of the working group until a month ago.
"The first review of the study by the Pavillion Working Group was unable to resolve many of the questions related to the sources of the compounds detected," said John Corra, director of the Wyoming Department of Environmental Quality and a member of the Working Group. He added that state agencies, representatives of Native American Tribes and the Bureau of Land Management all raised similar concerns to the EPA.
Mead noted that Wyoming and other members of the Pavillion Working Group have raised questions about the lack of replication of testing (typically findings from only two sampling events suggest that more sampling is needed before conclusions can be drawn). Members of the working group also have questions about the compound 2-BE, which was found in one sample out of the four that were taken, and why it was only found in results from one lab, while other labs tested the exact same water sample and did not find it.
"More sampling is needed to rule out surface contamination or the process of building these test wells as the source of the concerning results," said Tom Doll, supervisor of the Wyoming Oil and Gas Conservation Commission and a member of the Pavillion Working Group.
"My takeaway message is that both the EPA and Wyoming believe this is only the beginning of the process to understand the cause and scope of what was found," Mead said. "There are too many questions raised by what we have seen so far to not pursue further information.
"We do not want to predetermine the outcome of further research, but do feel the need for more thoroughness. I want to know what happened in Pavillion and feel the responsible approach is to do more testing," Mead said. "What we do know is that there has not been fracking in this area for several years and that there have been significant changes in our drilling regulations since then. Wyoming has led the country in regulating fracking because we want to protect our people, protect the environment and bring energy to the nation. More research will only help us."
Earlier testing did show problems with a few drinking wells near Pavillion. The working group has said it will continue to explore causes with those wells. Currently, the people with concerns about their drinking water are being provided water by industry. Wyoming has also commissioned a study to look at alternative water supplies for these residents.
The EPA is releasing the draft report for a 45-day comment period and will submit the findings to an independent scientific review panel.
In November the EPA's Region 8 office, which includes Wyoming, reported that the two monitoring wells specifically installed to test water supplies deep within an aquifer near gas drilling locations in Pavillion found high levels of benzene and other chemicals, including petroleum-related compounds (see Daily GPI, Nov. 14).
The sampling results were presented at a meeting attended by about half of Pavillion's 126 residents. According to EPA, a total of 42 private drinking water and four stock wells were sampled. Benzene, a carcinogen, measured as high as 50 times the EPA limit, the testing found. Elevated levels of diesel- and gasoline-grade organic compounds also were detected. High levels of methane were found in 10 of the sampled wells and elevated levels of 2-butoxyethanol phosphate were measured in nine wells.
The U.S. arm of Calgary-based Encana owns the natural gas field at the center of the controversy, and had planned to sell it to Legacy Reserves, based in Midland, TX. But Legacy has terminated the agreement for the proposed acquisition of the properties.
According to EPA, the Pavillion area has about 80 domestic wells. Pavillion provides municipal water to residents through eight groundwater wells. Private water wells just outside the town are used for drinking water, irrigation and stock watering, and are completed at depths from 50-750 feet or more. Pavillion is within the Wind River Indian Reservation west of Boysen State Park.