CHEYENNE, Wyo. (AP) — The U.S. Environmental Protection Agency and other agencies have begun a new round of water sampling in the area of a Wyoming gas field where the EPA says hydraulic fracturing may have caused groundwater pollution.
The EPA and Wyoming announced last month that they would collaborate on further testing in the Pavillion area. The announcement followed numerous objections raised by Gov. Matt Mead and other state officials about the adequacy of the science behind the EPA theory.
The U.S. Geological Survey and the Northern Arapaho and Eastern Shoshone tribes on the Wind River Indian Reservation also are involved in the new testing of groundwater from two monitoring wells, which started Monday.
The EPA also has been taking new samples of well water at homes in the area, said John Fenton, with the group Pavillion Area Concerned Citizens.
"They've been here the past few days taking samples," Fenton said Thursday. "I'm really not sure where they're at in it or how far along they are, but they are here."
Locals complain that their well water began to stink of chemicals around 2005, after fracking increased in their area. They approached the EPA after what they said was unwillingness by state regulators to investigate.
The EPA found high levels of the carcinogen benzene in the two monitoring wells it drilled in 2010. On Dec. 8, the EPA released its finding that hydraulic fracturing may have played a role in other pollutants found in the monitoring wells.
The report did not make a connection between fracking and the relatively low levels of hydrocarbons the EPA found in homeowners' water wells.
The Wyoming Department of Environmental Quality and the Geological Survey are teaming up to analyze some of the new water samples under a cooperative agreement, said Dave Ozman, spokesman for the Geological Survey in Denver.
"As part of the sampling, there will be a split sample and EPA will have some of that water analyzed in their labs. Then USGS will analyze the samples that we take," Ozman said.
The Geological Survey will test its samples either in-house or at a contracted outside lab, he said.
Fracking involves pumping water mixed with chemicals and fine sand down oil and gas wells to open up fissures and improve production. Environmentalists say fracking can pollute groundwater and the Pavillion report marked the first time the EPA had theorized such a link in a specific case.
The company operating in the Pavillion gas field is skeptical of the new testing. Experts working with Encana question how the EPA went about drilling two wells used to collect groundwater samples, said Doug Hock, a spokesman for the Calgary, Alberta-based petroleum company.
Cement used to construct the monitoring wells probably caused high pH in earlier sampling that contributed to the draft EPA finding, according to a letter dated Wednesday from Encana Vice President John Schopp to the EPA.
"The current condition of the EPA monitoring wells would make it difficult, if not impossible, to rehabilitate these wells to generate accurate groundwater monitoring data," the letter stated.
EPA spokesman Rich Mylott said the agency remains confident in the way that the monitoring wells were constructed.