West Lake Landfill Monitoring System
The West Lake Landfill Superfund Site, located at 13570 St. Charles Rock Road in Bridgeton, Missouri, has been a focus of environmental concern for several decades. The site, which was listed on the Superfund Program's National Priorities List in August 1990, has a complex history that dates back to the 1930s.
In early 2019, Bridgeton Landfill LLC resumed the Remedial Design process for Operable Unit 2 (OU-2) of the West Lake Landfill site. This process is currently underway, with EPA working to incorporate additional tasks into the Remedial Design. The Dashboard for Operable Unit 2 provides an estimate of progress made and the associated steps within the Remedial Design phase.
Meanwhile, the Remedial Design Interactive Map identifies locations sampled for radiologically impacted material prior to and during the Remedial Design for OU-1. Locations with radiologically impacted material are indicated with blue squares on the map. Pre-excavation confirmation sampling fieldwork for OU-1 began on July 21, 2025, and is currently ongoing.
Operable Unit 1 (OU-1) is defined as all radiologically contaminated areas of the site. The Confirmation Sampling and Analysis Plan for OU-1 is available on the Site Profile page. EPA issued a Record of Decision (ROD) for OU-1 cleanup in May 2008, requiring a landfill cover compliant with the Uranium Mill Tailings Radiation Control Act (UMTRCA) over OU-1. EPA updated the selected remedy for OU-1 in a September 2018 ROD Amendment, requiring a partial excavation of Radiologically Impacted Material (RIM) and an engineered UMTRCA cover over all RIM left on-site.
The table on the Dashboard page displays the estimated progress of the ongoing confirmation sampling fieldwork for OU-1. The Progress Dashboard provides an estimate of progress made and the associated steps within the Operable Unit 1 Remedial Design phase.
The site has been divided into three Operable Units (OUs). The Remedial Investigation Interactive Map displays the existing groundwater monitoring locations and the locations installed as part of the OU-3 Remedial Investigation. The map includes over 150 new locations from the North Surface Water Body, Inactive Sanitary Landfill, Closed Demolition Landfill, Buffer Zone, Lot 2A2, and Area 1 along St. Charles Rock Road. Well installation activities are ongoing for the OU-3 Remedial Investigation. The information on the OU-3 Dashboard is subject to change and should be used as a general guide only.
In 1973, uranium ore processing residues were brought to the landfill and used in typical landfilling operations, resulting in radiologically contaminated areas. Active quarrying for limestone took place on-site from 1939 to 1985, and municipal waste landfilling operations began during the 1950s.
In May 2019, EPA entered into an agreement with the Potentially Responsible Parties for OU-1 to perform the Remedial Design, which is currently underway. The West Lake Landfill Dashboard provides transparency into the Superfund process for the West Lake Landfill Superfund Site.
It's important to note that the Dashboard is subject to change and should be used as a general guide only. The map and tables provided are tools to help the public understand the ongoing remedial efforts at the West Lake Landfill Superfund Site. For the most accurate and up-to-date information, please visit the EPA's official West Lake Landfill Superfund Site webpage.
