The U.S. Army Corps of Engineers released the addendum to the feasibility study and the proposed plan for the Seaway Site in August 2008. The comment period for the proposed plan was from August 25, 2008, to October 24, 2008. A public meeting to receive public comments was conducted on Wednesday, September 24, 2008. The comment period was extended to November 28, 2008.
In October 2009 the Great Lakes and Ohio River Division Commander executed the record of decision for the Seaway Site, which identifies Alternative 6 - Containment with Limited Offsite Disposal, as the selected remedy for the site. The comments received on the proposed plan during the public comment period and the responses are included in the responsiveness summary portion of the record of decision. The record of decision for the Seaway Site is available by clicking the link in the Reports section below. The record of decision and supporting documentation are available at the Seaway Site Administrative Record File link below.
The selected remedy requires excavation of FUSRAP-related material outside the landfill boundaries that exceeds the cleanup criteria and requires shipping it off-site for disposal. It also requires the capping of Investigative Areas A, B, and C within the landfill boundaries. The cap for the FUSRAP-related material will be constructed of multiple layers of various types of soil, fabric, and geomembranes at least 4.5 feet thick. Long-term monitoring of FUSRAP-related materials in capped areas, surveillance, and maintenance will be performed by the federal government. The federal government will ensure that land-use controls are in place to prevent future access to and disturbance of the contained FUSRAP-related materials. The selected remedy in the record of decision will be protective of human health and the environment and comply with applicable or relevant and appropriate requirements.
In fiscal year 2015 the Buffalo District initiated excavation and off-site disposal of contaminated soil located beyond the landfill leachate containment system on the Seaway Site North Side, which was completed in fiscal year 2016.
During fiscal year 2017 the Buffalo District completed an investigation to delineate the extent of FUSRAP-related contamination within Seaway Southside. Analytical results from soil samples obtained from 15 investigation test pits in the Southside area of the site projected a 70 percent increase in soil volume requiring excavation and disposal. The FUSRAP-related soils form a lens measuring less than 1-foot thick that extended approximately 100 feet northwest of the previously identified area of contamination at a depth of around 12 feet beneath the landfill embankment. The Buffalo District also completed work plans for the excavation and off-site disposal of associated contaminated soils in fiscal year 2017.
Implementation of remedial action in Seaway Southside and the capping of Seaway Areas A, B, and C will occur later pending the completion of ongoing remediation at other FUSRAP sites and the availability of program funding.