New York Brownfield Site Achieves Closure

Case study highlights:

• Based on successful performance results, a pump-and-treat system was decommissioned in 2020, and the NYSDEC granted the site closure in August 2021
• By not having to operate and maintain the pump-and- treat system, substantial energy and cost savings were realized in this period
• Benchmark’s agile site management, making the switch from an ex situ to a PlumeStop in situ approach, saved time and money for their client

This case study reviews a former metals manufacturing facility in upstate New York contaminated with chlorinated volatile organic compounds (CVOCs) from the plating operations, predominantly comprised of tetrachloroethene (PCE) and trichloroethene (TCE). Benchmark Civil/Environmental Engineering & Geology, PLLC (Benchmark), a leading engineering and redevelopment consulting company headquartered in Buffalo, New York, quickly developed an in situ approach using PlumeStop® to achieve the project objectives and facilitate site closure. After evaluating remedial alternatives, Benchmark proposed a new Corrective Action Plan (CAP), specifying the in situ application of PlumeStop colloidal activated carbon, Hydrogen Release Compound® (HRC), a controlled-release electron donor, and Bio-Dechlor INOCULUM Plus® (BDI Plus), a bioaugmentation culture containing Dehalococcoides sp. and other beneficial microbes. PlumeStop remediation treatments rely on natural groundwater advection to move the CVOCs through a treatment zone. The CVOCs are immediately sorbed onto an immense surface of activated carbon which coats the aquifer materials. They are subsequently biologically transformed to non-toxic end products via reductive dechlorination from the co-applied HRC and BDI Plus. Together this passive treatment process is referred to as sorption-enhanced reductive dechlorination.