Fishbeck is implementing investigative and remedial activities at a legacy site in Michigan used to manufacture military equipment. Fishbeck was retained by the Settling Defendants (i.e., a combination of federal and private client responsible parties), established under a Consent Decree (CD) to implement a complex statement of work to address petroleum and chlorinated solvent-related volatile organic compounds (VOCs), metals, polychlorinated biphenyls (PCBs), and cyanide.
Strategies to investigate the nature and extent of impacts in various environmental media (e.g., soil, sediment, surface water, groundwater, soil gas) were developed using conventional and high-resolution site characterization methods (e.g., membrane interface, hydraulic profiling tool, amphibious drill rig, etc.). This information informed the design of an enhanced reductive dechlorination (ERD) system to treat a chlorinated solvent plume, provided data for a reinterpreted conceptual site model, and generated data to inform the next phase of remediation at the site. Other cleanup strategies that were implemented included the design and implementation of a soil vapor extraction (SVE) system to treat VOCs in the vadose zone, excavation of metals contaminated soil, construction of exposure barriers to restrict contact with PCB and cyanide impacted soils, and institutional controls (restrictive covenants and a public highway environmental license agreement). The majority of the field activities were implemented between 2019 and 2023. Notable accomplishments include the reduction of TCE and 1,1,1-TCA concentrations in the current ERD treatment area by 95%, meeting the cleanup objectives; removal of more than 7,500 pounds of VOC mass from the SVE treatment area; and, developing a revised CSM for the groundwater/surface water interaction (GSI). Efforts are ongoing to demonstrate the appropriateness of shallow alternative monitoring points to monitor venting groundwater as opposed to legacy monitoring wells positioned within the lower portion of the venting aquifer.
Completed activities by task area have been summarized in reports and submitted to Michigan Department of Environment, Great Lakes, and Energy (EGLE) for review and approval. An additional statement of work describing the next phase of remediation is currently in development with anticipated implementation commencing in 2026.
