National Grid was replacing a gas main on Thursday that runs through the waterway when 1,100 gallons of a petroleum-cement mixture spilled into the basin. Workers were "killing" the gas main by filling it with cement, when something went wrong, and the product spilled into the water.
Booms are in place and have contained the spill to just the basin. It's going to take several days for National Grid to clean up the spill.
OEM is advising people to avoid fishing and water activity in the area until further notice.
Paerdegat Basin is in the Canarsie section of Brooklyn and is a channel that leads into Jamaica Bay.
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