PAVILLION -- The U.S. Environmental Protection Agency has recommended that several Pavillion-area residents with private water wells find alternate sources of water for drinking and cooking.
The recommendation applies to at least 20 water wells, and that number could increase, according to the EPA.
EnCana Oil and Gas USA, which operates oil and gas wells interspersed throughout the farm and ranch community, has agreed to provide funding to a third party which will provide treatment or an alternate source of drinking water. However, details are not yet worked out.
The health concern is based on high sodium and sulfates that EPA officials believe are naturally occurring in the groundwater, and on the detection of petroleum compounds that officials believe shouldn't be in the groundwater.
EPA officials have not yet determined the source of the petroleum hydrocarbons, but they plan to make that determination in the agency's ongoing investigation.
The EPA and other federal officials have spent the past few days with Pavillion-area residents explaining their analysis of what's in the water and the potential health implications of continued consumption of the water. Officials highlighted their findings during a community forum in Pavillion on Tuesday evening.
"Last week it became clear to us that based on the information we gathered ... that you not continue to drink your water. We understand the gravity of that statement. We understand what it means to families of this community," said Martin Hestmark, assistant regional administrator at the EPA's Region 8 office in Denver.
Unsatisfied with responses from the Wyoming Department of Environmental Quality and local operator EnCana Oil & Gas USA, several Pavillion-area residents convinced the EPA to conduct its own investigation of possible drinking water contamination beginning in 2009. A second round of water sampling was conducted in January, and the EPA asked the Agency for Toxic Substances and Disease Registry to provide a health risk analysis based on the sampling.
Those results were revealed for the first time this week.
"In spite of the fact we may or may not know about the source of this contamination ... the citizens of this community need answers and they need it tonight," said Hestmark.
The EPA collected samples from 41 locations in January and sent them to four different laboratories that analyzed for more than 300 different constituents. Results suggested that two drinking water wells had compounds above the EPA's primary drinking water standard, one well for lead and phthalate and the other for nitrate.
The agency found petroleum hydrocarbons in at least 17 drinking water wells. But the EPA's primary focus for the no drinking and no cooking recommendation is within an area that includes more than 20 drinking water wells.
Agency for Toxic Substances and Disease Registry (ATSDR) officials said high levels of sodium are concerns for people with high blood pressure and other existing health conditions. Sulfates are a laxative, and the high sulfates concentration could cause digestive discomfort. The detection of methane in the drinking water is a concern in terms of the gas building up in enclosed areas such as laundry rooms and bathrooms, according to the ATSDR.
While some small traces of pesticides were detected in four private water wells, the concentrations are low enough to not warrant a health concern, according to the ATSDR. Both EPA and ATSDR officials stressed that that their findings are based on only two sampling dates, and that water quality can change drastically in a short amount of time.
For about the past five years, several rural landowners in the area have suspected their private drinking water wells were contaminated by oil and natural gas development. In 2005, EnCana Oil & Gas USA enrolled several contaminated drilling pits into state-level "voluntary remediation" programs.
The Wyoming Department of Environmental Quality confirmed that pollution from at least three of those pits has entered the same water zone in which several residents tap for drinking water. But EnCana and a pair of state regulatory agencies claim they know the extent of the pollution plume in the groundwater based on their ongoing monitoring and say that pollution has not entered nearby drinking water wells.
EPA officials, however, have not made their own judgment on the matter.
"We found groundwater associated with inactive oil and gas pits is in fact highly contaminated, which confirmed the fact that people already knew to be the case," said Ayn Schmit of the EPA Region 8 office.
She said the EPA has yet to complete an assessment of the sources of contaminants found in the drinking water wells, but the contaminated pits are a focus. Many people outside the regulatory regime have speculated that hydraulic fracturing performed on oil and gas wells in the area might have introduced the contaminants. However, Schmit reiterated that so far there's been no evidence to support such speculation.
Pavillion-area resident Louis Meeks said he believes the quality of his drinking water has continued to worsen over time.
"What I believe is we need to find the source. We need to get this shut down now before it just keeps spreading," Meeks said.
EnCana officials have promised to continue to cooperate with state and regulatory officials in the Pavillion investigation.
"While there's been a full year of additional testing, the science remains inconclusive," EnCana spokesman Randy Teeuwen said after the public forum. He said the EPA's findings "further confirms there is bad water in the area. But we've known that for a long time. It still does not point to oil and gas operations."