The Intermountain Waste Oil Refinery in Bountiful, Utah spent decades processing waste oil and blending petroleum products. Past operations contaminated soil and groundwater with trichloroethene (TCE), a hazardous chemical. EPA added the site to the National Priorities List (NPL), which identifies the country's most serious hazardous waste sites, and later deleted it in September 2019 after determining all appropriate cleanup was done.
The site was split into two operable units. Operable Unit 1 (OU1) tackled soil and subsoil contamination. The remedy requires any buildings on the property to have vapor mitigation systems so that TCE vapors cannot seep inside. Operable Unit 2 (OU2) addressed TCE in groundwater using a pump-and-treat system combined with dual phase extraction, which pulls contaminated groundwater and soil vapors from the same wells. The groundwater pumping system shut down in February 2006 after TCE levels dropped below the cleanup goal. In 2001, EPA also removed drums, containers, tanks, and debris from the property. Remedy construction finished in October 2006, and long-term groundwater monitoring continued through July 2019.
Health risks at the site included ingesting, touching, or inhaling contaminated groundwater, as well as vapor buildup inside buildings. Today, EPA says human exposure is under control, meaning no unacceptable exposure pathways remain across the entire site. Groundwater migration is also under control, with contaminated water stabilized and no unacceptable discharge to surface water. The site has reached "sitewide ready for anticipated use" status, meaning all cleanup goals for current and future land uses have been met and required land-use controls are in place. EPA will continue monitoring to confirm the contaminated groundwater stays within its original area.
The property was purchased in 2006 and redeveloped as an irrigation supply and design business. As of December 2024, one on-site business employs nine people and generates about $1,030,000 in annual sales. Five-year reviews of the site's status were completed in 2008, 2013, 2018, and most recently by the state in August 2023. The next five-year review is estimated between August and October 2028. Community members with questions can contact the EPA staff assigned to the site.
