The EPA has reached a settlement with the current and previous owners of the El Dorado refinery over possible groundwater pollution at the site.
EPA reached agreement with Frontier El Dorado Refining, a unit of Frontier Oil, which is now HollyFrontier; and former owner Equilon Enterprises, which is now Shell Oil Products US.
HollyFrontier and Shell will hire a project coordinator to investigate the potential pollution, plan on how to correct it and identify the funding for such work.
The EPA suspects that hazardous wastes released in earlier incidents also got into nearby soil and groundwater. The pollution could get into Constant Creek, Salt Creek and the Walnut River.
The refinery sits on more than 1,000 acres on the southwest corner of El Dorado and has been used for nearly a century.