Chemicals found in Wyoming water near gas drilling

Aug. 28, 2009
Federal environmental officials reported water sampling tests tentatively identified chemical contaminants—possibly from natural gas operations—in drinking water wells near Pavillion, Wyo., and more testing will be done to determine the chemical’s source.

Paula Dittrick
OGJ Senior Staff Writer

HOUSTON, Aug. 28 -- Federal environmental officials reported water sampling tests tentatively identified chemical contaminants—possibly from natural gas operations—in drinking water wells near Pavillion, Wyo., and more testing will be done to determine the chemical’s source.

The US Environmental Protection Agency on Aug. 11 issued a 44-page report outlining its water sampling results in Fremont County, which is a rural area with gas production. Field testing was done during March and again in May.

“There are numerous gas wells, gas well waste pits, and agricultural chemical storage areas that could be potential sources of contamination,” said the report. Among contaminants found, one was 2-butoyethanol, or 2-BE, which EPA officials say is used by the gas industry.

This chemical is a solvent used in hydraulic fracturing, but EPA has yet to determine the cause of the contamination. The water tests were conducted because some Pavillion-area residents complained about their drinking water’s color, smell, and taste.

EnCana’s Wyoming operations
EnCana Corp. has 248 wells in the area, EnCana spokesman Doug Hock of Denver told OGJ. The wells are in the Fort Union formation in the Wind River basin. EnCana acquired the wells in 2004.

“We have not done any drilling or completions there since 2007,” Hock said, adding that EnCana is cooperating with the EPA investigation. “At this point, we just don’t know,” if the chemical found in the water might have come from fracturing, he said.

Luke Chavez, EPA Region 8 project manager in Denver, said there also are coal mines in the area. EPA has yet to determine the volume of 2-BE in the water. The study was conducted under the EPA’s Superfund program.

Chavez noted that the substances found by EPA are found in some household products and in degreasers. He said it’s possible the contaminants came from a degreaser used around a gas production well rather than from fracturing.

“We cannot pinpoint any specific source at this time,” Chevez said. “Further sampling is needed, and we are meeting with stakeholders to determine the best way to approach the next sampling effort.”

Fracturing traditionally is a state-regulated practice, although several federal lawmakers have expressed concerns about whether it should be regulated under federal law.

In June, some members of Congress introduced legislation that would give EPA the authority to regulate fracturing under the Safe Drinking Water Act. Hydraulic fracturing is crucial to the development of shale gas plays (OGJ, July 6, 2009, p. 18).

The American Petroleum Institute has issued recommendations to ensure the chemical mixtures used in fracturing jobs remain isolated from groundwater.

Contact Paula Dittrick at [email protected].