And the material would still have to be capped with 12 inches of sand, top soil and gravel and stone.
The EPA said even that option “would not return the Grasse River to pristine conditions” and would mean removing and properly disposing of 1.5 million cubic yards, or 1 million tons, of contaminated sediment, which would take three times as long to complete.
Alcoa, Reynolds Metals and General Motors had discharged pollutants in the St. Lawrence River and its tributaries since the 1950s, including polychlorinated biphenyls (PCBs), a known carcinogen.
On March 27, a $20 million settlement was reached that requires Alcoa and Reynolds Metals Company to pay $18.5 million in damages for releasing hazardous material into the St. Lawrence.
That money is in addition to a $1.8 million settlement as part of the 2011 General Motors bankruptcy action.
It came on the heels of Aloca’s announcement that it will invest $52 million in modernization and upgrades at its Massena operations.
Congressman Bill Owens (D-Plattsburgh) hailed the remediation project.
“Finalizing a plan to clean up the Grasse River is another positive step forward for Alcoa, for workers and labor at the facility and for their families in the community,” he said.
As well, he said, the announcement “eliminates a roadblock that has created uncertainty around Alcoa’s modernization, and I applaud this progress.”
A study in the 1970s by the National Institute of Environmental Health determined the concentration of PCBs in the breast milk of young Mohawk mothers was being transferred to their babies, and a Health Department study between 1986 and 1992 found Mohawk mothers had twice the level of PCB contamination in breast milk than Caucasian mothers.
After the fish ban was put in place in 1990, subsequent testing revealed no significant difference between the PCB levels in Mohawk mothers’ milk and that of Caucasian mothers.