Between 1973 and 1978, Monroe Auto Equipment Co. dumped nearly 15,000 cubic yards of electroplating sludge into an abandoned sand and gravel pit near Paragould, Arkansas. The sludge came from settling ponds at the company's manufacturing plant. It contaminated both soil and groundwater with metals and organic solvents.
EPA identified 21 contaminants of concern at the site. Metals found there include arsenic, beryllium, cadmium, chromium, copper, lead, manganese, mercury, and nickel. Organic chemicals include trichloroethene, 1,2-dichloroethene, chloroethene (vinyl chloride), and bis(2-ethylhexyl)phthalate. Antimony and cyanide were also identified. These substances were present in groundwater, soil, and sludge across the site.
The site was added to the National Priorities List (NPL) on August 30, 1990. EPA divided it into one site-wide operable unit and began a remedial investigation in June 1991. A cleanup plan was selected in September 1996, calling for monitored natural attenuation, an engineered cap, and institutional controls. A plan amendment in November 2000 changed the approach to include excavation and offsite disposal of contaminated materials. Final remedial work ran from August 1999 through May 2006, and construction was completed in September 2001. Groundwater sampling in April 2008 confirmed no wells contained contaminants above remedial goals in the Upper Wilcox aquifer. A five-year review in 2009 confirmed all cleanup goals had been met.
EPA signed the Final Closeout Report in April 2014 and published a Notice of Deletion in the Federal Register on August 14, 2014. The site was officially deleted from the NPL on September 29, 2014. Human exposure is under control, contaminated groundwater migration is stabilized, and there is no unacceptable discharge to surface water. All groundwater monitoring has been terminated.
Community members with questions can contact the EPA Community Involvement Coordinator, or the Remedial Project Manager for technical cleanup questions. The Arkansas Department of Environmental Quality (ADEQ) is also available for local inquiries.
