SRSNE Superfund Site
For the SRSNE Superfund site, GEI evaluated PFAS concentrations in extracted groundwater and other offsite locations to support the approval of groundwater discharge to a sanitary sewer by the Connecticut Department of Energy and Environmental Protection (CT DEEP). This included sampling at the local publicly owned treatment works (POTW) and a nearby river to gather data representative of non-site-related PFAS levels.
GEI then supported the development and implementation of a pilot study to assess the effectiveness of liquid activated carbon in mitigating PFAS migration in groundwater. The study involved injecting a carbon-based product into a series of trenches to minimize potential downgradient migration of PFAS and other constituents. This was the first application of this product to address PFAS contamination in the United States.
The successful application of the pilot study provided significant cost savings, exceeding $1 million, for the potentially responsible party (PRP) group. It enabled continued execution of the planned VOC-based remediation without requiring a Record of Decision (ROD) amendment, decommissioning of 12 groundwater recovery wells and their associated treatment systems, and allowed for the discharge of remaining groundwater to a sanitary sewer without additional treatment.