Valley Park TCE sits in Valley Park, Missouri, in St. Louis County. Two former industrial operations created the contamination. Wainwright Industries ran a metal stamping shop from 1949 to 1979 and used solvents including trichloroethylene (TCE) and tetrachloroethylene (PCE). Valley Technologies has operated metal processing since 1954 and also released TCE into soil and groundwater. The site was added to the EPA's National Priorities List (NPL) in 1986, marking it as a priority for federally managed cleanup.
The main contaminants are chlorinated solvents, primarily TCE and PCE, found in both soil and groundwater across two source areas. Groundwater contamination exceeds drinking water standards, but residents use the public water supply, avoiding that exposure route. Vapor intrusion, where chemicals move from soil or groundwater into building air, was detected at the Wainwright property in 2014. Mitigation systems were installed and confirmed effective. Assessments at nearby properties have been conducted since 2012. EPA has determined that human exposure is under control and groundwater migration is stabilized.
Cleanup has moved through several phases. At the Wainwright property, soil vapor extraction began in 1999 and a groundwater extraction and treatment system started that same year. EPA issued an amended cleanup plan in November 2020 calling for in-situ thermal treatment of remaining soil contamination. That thermal remediation work started on August 30, 2024, and continues now. At the Valley Technologies property, about 5,000 cubic yards of contaminated soil were excavated and sent to landfills between 2005 and 2006. A groundwater extraction and treatment system also operates there, though contamination levels have remained higher than expected. EPA amended the cleanup plan in September 2019 to add in-situ thermal remediation for deeper soil, and that work began in September 2022 and is ongoing.
EPA's most recent five-year review, completed September 8, 2023, found that current cleanup methods protect human health and the environment. Long-term protection depends on completing the thermal remediation work at both properties. Environmental covenants filed with St. Louis County restrict soil disturbances and prohibit new groundwater supply wells at both locations. Zoning restrictions also prevent residential development. The Wainwright soil work is estimated to finish between September and November 2027, Valley Technologies soil work between September and November 2026, and the site is anticipated to be ready for full reuse between September and November 2028. Four businesses currently operate on the site, employing 42 people.
Community members with questions can contact the EPA Community Involvement Coordinator or the Remedial Project Manager. For state-related questions, contact the Missouri Department of Natural Resources. Site documents are available at the Valley Park Community Library, 320 Benton St, Suite B, Valley Park, Missouri 63088.
