There's an oil field near downtown Poplar, Montana and it's contaminating the city's water supply. By EPA estimates, more than 40 million gallons of brine have entered the drinking water aquifer over five decades. Now, the agency is holding three oil companies at least partly responsible for the contamination.
The EPA announced last week it has ordered Murphy Exploration, Pioneer Natural Resources, and Samson Hydrocarbons to pay the city $320,000 to reimburse costs related to water infrastructure and relocating water wells. They will also have to monitor the city's public water supply and provide treatment, or an alternate drinking source, if the water becomes contaminated to the point where it's an official public health risk.
The contamination involves highly saline wastewater that contains trace metals, inorganic salt concentrations, and volatile organic compounds, but the city's treated water has been deemed safe to drink. Yet monthly samples collected by the oil companies show "an upward trend in total dissolved solids, chloride and sodium," and an EPA scientist said the water supply faces imminent danger.
The Montana Native News Project quotes EPA scientist Nathan Wiser: "The facts we've seen have certainly shown that at certain monitoring well locations certain water wells have gone from pretty good to pretty bad in what in my mind is a pretty abrupt fashion, in a matter of a year or two."
The contamination from the oil field is not exactly news: "EPA, the State of Montana, the Fort Peck Tribes, the U.S. Geological Survey and other agencies have been aware of groundwater contamination in the East Poplar oil field for several decades," said the EPA's own press release about the agreement.
The EPA had tried to act with an emergency order in 2010, but the companies appealed in federal court. Last week's agreement is a result of the mediation process that resulted from that appeal.