Investigators with the Ministry of the Environment, Conservation and Parks have pinpointed the suspected cause of a monthslong spill of oil into the city's storm sewage system.
In November, an oily sheen was observed on the water of the creek that runs between the Gateway Casino Sault Ste. Marie and its nearby parking lot. An absorbant boom was placed to prevent the substance from travelling further into the St. Marys River.
Gary Wheeler, a spokesperson for the ministry, said on Thursday that the suspected source of the spill was found last month.
"The ministry and Sault Ste. Marie Public Works traced the sheen through the sewer system to a specific city block on North Street. On Feb. 18, we uncovered an underground storage tank on Canadian Pacific Kansas City rail property," Wheeler said.
He added: "The tank contained diesel fuel, and approximately 3,800 litres were pumped out for disposal. The tank has been removed and an assessment of contaminated soil in the area by consultants working for the rail company is underway."
On Thursday, a rusted metal tank with a gaping hole in its side could be seen near the rail crossing on North Street.
Dan Perri, the city's director of public works, said: "The source of the contamination originated from private property, which made its way into the city storm sewer, where it was contained by public works staff and a contractor hired by the city."
Wheeler said the sheen at the creek has become less noticeable since the suspected source has been identified and clean up has begun.
So far there has been no word from the ministry about possible environmental charges.
"The ministry will continue to follow up with area property owners on the assessment and remediation of any soil and groundwater impacts related to the diesel contamination," said Wheeler.