MASSENA — The Environmental Protection Agency and Arconic held their final open house information session of the season on Wednesday to discuss activities associated with the Grasse River Superfund site.
The sessions have been held the second Wednesday of each month, starting in April when the construction season began, to keep community members abreast of the latest information regarding the remediation of the lower Grasse River. The initial session was held at the Massena Community Center, and later sessions have been held at the Hawkins Point Visitors Center.
Representatives from the Environmental Protection Agency and Arconic staff were available to discuss the work that has been going on to remediate the Grasse River, and to answer questions from the public.
Since 2013, Arconic has been working out the details of how the dredging and capping will be carried out, under EPA oversight. In 2013, the EPA selected a cleanup plan for the site that called for dredging and capping of PCB-contaminated sediment in the 7.2-mile stretch of river. Arconic is performing the work, which is estimated at $243 million, under an EPA order.
This year’s activities have included near-shore sediment dredging, material processing at the staging area and floodplain removal. Under the EPA’s approved remediation plan, the dredging of sediments from the river’s near-shore areas began in the spring to remove about 100,000 cubic yards of PCB-contaminated sediment from the near-shore areas in a 7.2-mile stretch of the Grasse River. The contamination is a result of past waste disposal practices at the Alcoa West (now Arconic) facility.
Mechanical dredges have been used to remove PCB-contaminated sediment from near-shore areas of the project using environmental buckets. The excavated sediment has been taken by barge to a staging area next to the river, near the intersection of county Route 42 and state Route 131 for off-loading, processing and de-watering.
Contaminated sediment has been collected and pre-treated at the staging area before it was sent to the Arconic West plant for additional treatment and subsequent discharge into the Grasse River. Processed sediment has been loaded into dump trucks and taken to a permitted landfill at the Arconic West plant.
Capping of the river’s main channel will take place in 2020 and subsequent years to isolate the PCBs from the surrounding environment. Reconstruction of habitat affected by the project is scheduled to take place in 2021.
The overall goal is to reduce PCB levels in fish and other organisms in the river for the long-term protection of human health and the environment.
This year’s project activities are expected to continue through November, weather permitting, and will resume in the spring.