The U.S. Environmental Protection Agency (EPA) Dec. 8 released a draft analysis of data from its Pavillion, Wyo., groundwater investigation. At the request of Pavillion residents, EPA began investigating water quality concerns in private drinking water wells three years ago. Since that time, in conjunction with the state of Wyoming, the local community, and the owner of the gas field, Encana, EPA has been working to assess groundwater quality and identify potential sources of contamination.
EPA constructed two deep monitoring wells to sample water in the aquifer. The draft report indicates that groundwater in the aquifer contains compounds likely associated with gas production practices, including hydraulic fracturing. EPA also re-tested private and public drinking water wells in the community. The samples were consistent with chemicals identified in earlier EPA results released in 2010 and are
generally below established health and safety standards.
To ensure a transparent and rigorous analysis, EPA is releasing these findings for public comment and will submit them to an independent scientific review panel. The 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.
Natural gas plays a key role in our nation?s clean energy future and the Obama Administration is committed to ensuring that the development of this vital resource occurs safely and responsibly. At the direction of Congress, and separate from this groundwater investigation, EPA has begun a national study on the potential impacts of hydraulic fracturing on drinking water resources.
?EPA?s highest priority remains ensuring that Pavillion residents have access to safe drinking water,? said Jim Martin, EPA?s regional administrator in Denver. ?We will continue to work cooperatively with the State, Tribes, Encana and the community to secure long-term drinking water solutions. We look forward to having these findings in the draft report informed by a transparent and public review process. In consultation with the Tribes, EPA will also work with the State on additional investigation of the Pavillion field.?
Findings in the Two Deep Water Monitoring Wells:
EPA?s analysis of samples taken from the Agency?s deep monitoring wells in the aquifer indicates detection of synthetic chemicals, like glycols and alcohols consistent with gas production and hydraulic fracturing fluids, benzene concentrations well above Safe Drinking Water Act standards and high methane levels. Given the area?s complex geology and the proximity of drinking water wells to ground water contamination, EPA is concerned about the movement of contaminants within the aquifer and the safety of drinking water wells over time.
Findings in the Private and Public Drinking Water Wells:
EPA also updated its sampling of Pavillion area drinking water wells. Chemicals detected in the most recent samples are consistent with those identified in earlier EPA samples and include methane, other petroleum hydrocarbons and other chemical compounds. The presence of these compounds is consistent with migration from areas of gas production. Detections in drinking water wells are generally below established health and safety standards. In the fall of 2010, the U.S. Department of Health and Human Services? Agency for Toxic Substances and Disease Registry reviewed EPA?s data and recommended that affected well owners take several precautionary steps, including using alternate sources of water for drinking and cooking, and ventilation when showering. Those recommendations remain in place and Encana has been funding the provision of alternate water supplies.
Before issuing the draft report, EPA shared preliminary data with, and obtained feedback from, Wyoming state officials, Encana, Tribes and Pavillion residents. For more information on EPA?s Pavillion groundwater investigation, visit: http://www.epa.gov/region8/superfund/wy/pavillion/index.html.
Further Franking Concerns
After 11 earthquakes in eastern Ohio over the last year, the Ohio Department of Natural Resources ordered a stop to the operation of a fluid injection well near Youngstown that is suspected of causing the rumbles. While conclusive evidence cannot link the seismic activity to the well, department director James Zehringer has adopted an approach requiring prudence and caution regarding the site used for natural gas drilling waste from western Pennsylvania.
?Our top priority is the health and safety of the public and the protection of Ohio?s natural resources,? Zehringer said. ?We are going to make sure this process is done right and won?t hesitate to stop operation of disposal sites if we have concerns. And while our research doesn?t point to a clear and direct correlation to drilling at this site and seismic activity, we will never gamble when safety is a factor.?
The Class 2 injection well is owned and permitted by Northstar Disposal Services LLC of Youngstown. Following a series of low-level seismic events during the past year in the area surrounding the Youngstown Township injection well, the ODNR invited Columbia University?s Lamont-Doherty Earth Observatory to position four seismometers in the area to capture more detailed information about seismic activity.
?Information freshly obtained from the Columbia University scientists, and further analyzed by ODNR geological experts, indicates that an earthquake occurred on Dec. 24, approximately two miles below and within a mile of the injection site,? Zehringer said. ?As a precautionary measure we?ve reached agreement with the well?s owner to halt injections until we are able to further assess and determine any potential links with recent seismic events.?
So far this year, ODNR?s seismic monitoring network has documented 10 seismic events occurring in 2011 within two miles of this injection well. Each of these events registered at 2.7 magnitude or lower. Generally, only earthquakes that register above 4 magnitude are known to cause surface damage. As a relative measure, a 4 magnitude event would release approximately 40 times the energy of a 2.7 magnitude event.
There are 177 Class 2 deep well injection sites operating in Ohio.
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