Envirochem Corp. is a 6-acre former solvent-reclaiming facility in Boone County, Indiana. It operated from 1977 to 1982, handling resins, paint sludges, waste oils, and flammable solvents. Poor waste management, spills, unauthorized discharges, and unapproved burning of chlorinated compounds left behind widespread contamination. EPA placed the site on the National Priorities List in September 1983, marking it as a priority for investigation and cleanup.
Forty-seven contaminants of concern have been identified at the site. These include volatile organic compounds such as trichloroethene, tetrachloroethene, benzene, toluene, and chloroform. The site also contains heavy metals including arsenic, chromium, lead, and zinc, along with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons, phthalates, and phenol. Contamination has been found in groundwater, soil, sediment, surface water, and buildings across the site.
EPA selected a cleanup remedy in September 1987 and updated it in June 1991. The approach includes a permanent cap over contaminated areas, soil vapor extraction to pull volatile organic compounds from soil, and groundwater treatment. Construction began in 1998 and was completed in September 2009. In 2006, EPA upgraded the soil vapor extraction system and added a Permeable Reactive Gate System, a barrier wall that lets contaminated groundwater flow through chemically reactive material for treatment.
The most recent five-year review, completed in March 2023, found the remedy protective in the short term. However, the upgraded soil vapor extraction system has not significantly reduced contaminant levels in groundwater, and the Permeable Reactive Gate System has not functioned properly. Contaminated groundwater migration has not been stabilized. EPA and the site's responsible parties are evaluating additional cleanup measures and may modify the remedy to ensure long-term protection. Human exposure is currently under control, with no unacceptable exposure pathways identified. Zoning restrictions and other institutional controls limit land uses such as residential development that would be incompatible with the current cleanup level.
Community members with questions about the site can contact the EPA's Community Involvement Coordinator or Remedial Project Manager. The Fifth Five-Year Review Report from 2023 is available for those who want a detailed look at current findings. The next five-year review is estimated between March and May 2028.
