A small family business has been fined $70,000 under the Ontario Environmental Protection Act for the discharge of waste oil from a property that had previously been rented to two trucking companies.

The fine is linked to an October 2020 investigation in which provincial Environment, Conservation and Parks staff traced the source of a football-field-sized oil sheen in Lake Ontario to 3473 Wolfedale Road in Mississauga, Ont.

Two temporary workers had been hired to remove a pair of long-unused 500-gallon storage tanks on the property, which was being prepared for sale. But a pipe broke in the process and waste oil was released, the ministry says. Some of that oil flowed into a catch basin and trench, making its way down Wolfedale Creek and into the Credit River.

Lab reports revealed a mixture of biodegraded petroleum products with possible trace amounts of diesel.

Anthony Cosentino — a director of Domenic Cosentino and Company, which owned the site – thought the tanks contained rainwater rather than oil, but didn’t confirm the contents or supervise the clean-up, the ministry says.

He promptly hired a contractor to clean up the discharge when contacted, it adds.

Domenic Cosentino and Company was convicted of two violations under the Environmental Protection Act and fined $70,000 plus a victim fine surcharge of $17,500. Cosentino was personally convicted of one violation and fined $5,000 plus a $1,250 victim surcharge.