The Ministry of the Environment was called to investigate a spill in Little Lake, Peterborough.
At approximately 10:30 am On Wednesday, firefighters in Peterborough fought back at the lake near the marina as a result of reports from anglers and boaters of an unknown substance in the water.
Firefighters worked to contain the substance, using dams to help stop its spread.
An employee of the city took a sample of the test substance.
It is not yet known how much of the substance was in the water.
In March 2018, a broken deletion line from General Electric Peterborough caused the leakage of an oil product into the lake, located in the center of the city.
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