Grasse River dredging resumes next month

The U.S. EPA announced yesterday that in-river work will resume next month to address sediment contaminated with polychlorinated biphenyls (PCBs) at the Grasse River Superfund Site (aka Alcoa Aggregation) in Massena, New York.

“It’s exciting to see the tremendous progress that has been made as we near the finish line for this critically important project,” said Walter Mugdan, Acting Regional Administrator.

“EPA, the New York State Department of Environmental Conservation, and the Saint Regis Mohawk Tribe continue to work together on the oversight of the various components of the project.”

In 2013, EPA selected a cleanup plan for the site that called for dredging and capping of PCB‐contaminated sediment in a 7.2‐mile stretch of river.

The 2021 work will primarily include placement of a 12-inch sand, gravel and/or stone cap in the lower five miles of the main river channel from the Route 131 Bridge to the mouth of the Grasse River, covering over 200 acres; sand backfilling in areas dredged in 2020 near Snug Harbor; and habitat reconstruction throughout the site.

The major elements of the in-river work are expected to be completed by the end of 2021. COVID-19 protocols will continue to be followed and safeguards will be maintained for the protection of site workers and the community.

To support this year’s work, an extended underwater pipeline will be used to transport some clean capping material from two staging areas to river locations.

According to EPA, this operation will occur 24 hours a day, six days a week.

The pipeline will be submerged along the river shoreline, with some floating sections near the cap operations.

“The remainder of the capping material will be transported by barges pushed by tugboats and placed mechanically on the river bottom using excavator-type buckets. On-river warning signs will be posted to alert oncoming boating traffic,” said EPA.

Howmet Aerospace Inc. (formerly Arconic Inc.) is responsible for performing the work at the site on behalf of the parties responsible for the Superfund cleanup.