Under contract with APG's Installation Restoration Program (IRP) in support of its Interagency Agreement compliance efforts, Sovereign worked under a Performance-Based Contract (PBC) to provide guaranteed fixed-price remediation of chlorinated solvents. The main performance objective was the attainment of Remedy in Place (RIP) at the following four sites: Cluster 9 Nike Control Area, Cluster 13 (School Fields) Groundwater, Southern Bush River Area Groundwater Operable Unit 1, and Ft. Hoyle (Cluster 19).
Sovereign prepared Remedial Design work plans, ensuring that all proposed plans are consistent with the Federal Facilities Agreement (FFA), Army objectives, MDE, and EPA requirements. Sovereign also created work plans in support of several field implementations and pilot studies, as well as developed extensive groundwater models to demonstrate site characteristics and select the most feasible remedial alternative to the 4 PBC sites.
Sovereign successfully obtained RODs for Cluster 9 and Cluster 19. Sovereign chose Soil Vapor Extraction (SVE) with Air Injection (AI) and Land-Use Controls (LUCs) as the site remedy for Cluster 9, and LUCs for Cluster 19. Sovereign installed and started up the SVE/AI system at Cluster 9. While the system was running, Sovereign provided O&M for the SVE/AI system, which obtained its performance criteria within 9 months of beginning operation, and saw a 99.7% decrease in soil gas concentrations in the source zone, well in excess of the 70% performance objective specified in the ROD.
Sovereign drafted the FS documents for Cluster 13 that focus on the preferred source control remedy to treat DNAPL through ERH. In support of the FS, an ERH pilot study is in the design stage. In support of the pilot study several new groundwater monitoring wells were installed and sampled for VOCs using passive diffusion bags (PDBs). For the Southern Bush River Groundwater OU-1, Sovereign worked with the contractor for Southern Bush River Groundwater OU-2 and OU-3 to maximize the remedial alternatives for the entire affected aquifer and limit the long-term O&M costs. Sovereign also assessed the use of a membrane interface probe and an SVE pilot study to support the feasibility study for the Southern Bush River Groundwater OU-1.