IESI – Seneca Meadows, Inc. – Remedial Design for Closure of Class 2 Inactive Hazardous Waste Site at the Tantalo Waste Disposal Site
Successfully achieving reclassification of an inactive hazardous waste site
Cornerstone personnel assisted Seneca Meadows, Inc. (SMI), the largest privately held solid waste management facility in New York State, with closure of a Class 2 inactive hazardous waste site (Tantalo). The work included site investigation, an aquifer test, design of two operable units, and support of routine operations, maintenance and monitoring. As a result of Cornerstone’s work, the site has been reclassified to the less restrictive Class 4 designation, indicating that the site has been properly closed and requires proper monitoring.
Cornerstone personnel’s site investigation efforts included a groundwater program to assess the extent to which natural attenuation was controlling a trichloroethene (TCE) plume from the site. The groundwater program demonstrated that the plume was stable due to reductive dechlorination, and was contained on property owned by SMI. Cornerstone personnel also conducted a fractured rock aquifer test to characterize the site hydrogeologic conditions and a tracer test to quantify the effective porosity of the bedrock water-bearing zone. The test identified two distinct water-bearing zones that had been mapped by others as a single unit.
The remedial design included site closure and groundwater remediation. Site closure included a geocomposite cap, drainage controls, gas controls, a leachate/groundwater collection system, waste pullback, a cutoff wall along adjacent Black Brook, and relocation of the site access road. The groundwater remediation included design of a program using electron donor materials to enhance natural attenuation through reductive dechlorination.
Following design, Cornerstone personnel provided construction observation and final certification services for both operable units. Currently, Cornerstone is assisting SMI with routine operations, maintenance and monitoring.