KANSAS CITY, Kan., – The Environmental Protection Agency has reached an administrative settlement with the current owner-operator and a historical owner of the Frontier El Dorado oil refinery in El Dorado, requiring the companies to take a series of actions to investigate environmental contamination at the property.

Frontier El Dorado Refining LLC, which owns and operates the facility; and Equilon Enterprises LLC, doing business as Shell Oil Products US, which has historical ownership interests in the facility, are listed as the respondents of an administrative order on consent issued by EPA in Kansas City, Kan.

Consisting of more than 1,000 acres on the southwest corner of El Dorado, the property has been in use as an oil refinery for almost a century. Since 1980, the facility has been classified as a large quantity generator of hazardous wastes, under terms of the federal Resource Conservation and Recovery Act (RCRA). It produces motor fuels, residential fuel oils and petroleum coke.

Previous environmental investigations at the refinery have identified releases of benzene, lead, hexavalent chromium, toluene, ethyl-benzene and xylenes, among other chemicals. Investigation suggests hazardous wastes or constituents released at or from the site may have contaminated groundwater, surface water and soil on or near the site.

Impacted groundwater could pose significant threats to nearby streams, including Constant Creek, Salt Creek and the Walnut River.

EPA’s settlement with Frontier and Shell requires the companies to integrate and continue environmental work previously performed at the refinery under the supervision of the Kansas Department of Health and Environment.

As first steps, the settlement requires Frontier and Shell to designate a project coordinator within 10 days, and notify EPA within 30 days of the names and qualifications of the primary persons, companies and laboratories to be used in carrying out the work. The settlement further outlines a series of timeframes for beginning and/or completing various additional actions and phases of work at the site. Frontier and Shell will continue to operate existing remedial systems designed to contain groundwater contamination within the refinery boundaries.