Portsmouth Naval Shipyard consists of over 270 acres of land and was formerly used by the Navy to design, construct, repair, and overhaul submarines. CDW was retained to provide Remedial Investigation and Feasibility Study and design support, as well as technical reviews of Work Plans, Technical Memorandums, and monitoring reports for four separate sites on the campus:
- Site 6 was impacted by extensive soil contamination from metals, PAHs, Petroleum, and PCB. Our team reviewed a Remedial Action Work Plan proposing a patented emulsification process designed to stabilize the hazardous constituents in the fill material.
- Site 8 was filled with various industrial wastes. CDW reviewed the landfill closure plan and provided field oversight of the final landfill cap construction.
- Site 32 was an area filled with dredge spoils that had potential shoreline impacts from deposits of slag. We reviewed a Quality Assurance Plan for surface water and sediment sampling related to the disposition of the slag and recommended a comprehensive slag depositional survey. The survey was done and confirmed our conceptual model of likely slag and metal migratory and depositional patterns to the off-shore environment. CDW provided recommendations on how to adjust the QAP consistent with Data Quality Objective.
- Site 10 was a filled area potentially contributing to off-shore impacts specifically from lead. CDW reviewed Technical Memorandums related to lead screening levels for human health risk assessment, and a site specific evaluation of the appropriate analytical methods for lead.As a result of our studies, our team of experts was able to offer the EPA alternative approaches to analyzing samples, conducting additional flow net analyses, reviewing supplementary diagrams and tracer tests as well as with the installation of monitoring wells at key locations.