This Administrative Settlement Agreement and Order on Consent (ASAOC) requires a Remedial Investigation and Feasibility Study (RI/FS) for the West Lake Landfill Superfund Site, Operable Unit 3 (sitewide groundwater). The parties to this agreement are Bridgeton Landfill, LLC, Cotter Corporation (N.S.L.), and the U.S. Department of Energy. The ASAOC will result in the collection of data necessary to refine the current understanding of the hydrogeologic system, evaluate background groundwater quality near the Site, determine the extent of groundwater impacts occurring at and near the Site, provide predictive tools/models to evaluate potential future impacts, and, based on the information collected, identify potential groundwater remedies that may be implemented at the Site.