Hydro One teams in clean up mode after oil spill leaks into the Don River

Cleanup crews from Hydro One are continuing their work at the Don River on Saturday after an oil spill from one of its transmission sites leaked into the river a day earlier.

Nancy Clark, a spokesperson for Hydro One, said one of the company's transformers at the Bathurst Transmission Station in North York failed early Friday, resulting in insulating mineral oil being released. 

"We immediately dispatched our environmental emergency response teams and cleanup efforts are underway," Clark told CBC Toronto.

The mineral oil is an insulating oil that is widely used for the safe operation of electricity systems, she said.

"On site we do have containment units in the event that mineral oil does leak from any of our equipment, but due to the additional volume from the rain and the snow that we've received over the last few days, it resulted in those units overflowing."

Vacuum truck and absorbent booms are being currently being used to recover as much oil as possible, she said.

Spill site is 'active scene,' Hydro One says

Clark said the site of the spill is still an "active scene." An investigation is underway to determine how much mineral oil has been released, how much is in the containment pits and how much has been recovered so far. 

They will be carrying out an additional assessment and any remediation work that is necessary in the coming weeks and months, she said.

"We take this responsibility very seriously and our goal when responding to spills is to prevent or mitigate any potential impacts to the environment." 

Clark anticipates the initial emergency portion of the cleanup alongside the creek and outside the station could take two to three days.

She said Hydro One has been working with the city of Toronto as well as the ministry of environment, conservation and parks to resolve the issue.

'It's very concerning,' councillor says

Coun. Mike Colle, who represents Ward 8, Eglinton–Lawrence, said this is the first time — as far as he knows — that there's been a spill of a chemical oil into the Don River.

While Hydro One says residents of the area should not be concerned, Colle says otherwise. 

"It's very concerning because this is one of Toronto's two main rivers, this and the Humber, plus the Don flows eventually to Lake Ontario and that's the water we drink," Colle told CBC News. 

"It's a very, very sensitive ecosystem in the middle of the city."

The councillor said he will get a full report on the spill and make sure there's a thorough follow up.

No safety concerns for drinking water, city says

In an emailed statement to CBC News the city says it has been contacted by Hydro One, and the Ministry of the Environment Conservation and Parks is also aware of the spill.

The city is assuring people that Toronto's drinking water is safe.

"There are no safety concerns for Toronto's drinking water. Toronto's drinking water is continuously monitored, tested and analyzed to ensure it meets the strict standards of Toronto Public Health, the province of Ontario and government of Canada," the statement from the city said.

The city says Toronto Water's accredited lab:

• Tests drinking water every six hours (more than 6,000 times a year.)
• Conducts more than 20,000 tests at the water treatment plants annually.
• Conducts 15,000 bacteriological tests on samples collected from the water distribution system annually.

Richard Francella, senior communications advisor at Hydro One, said the Bathurst Transmission Station is located at 155 Goddard St., near the intersection of Bathurst and Sheppard.

Francella said the cleanup efforts are underway downstream, with river booms deployed along the west branch of the Don River at 4090 Yonge St., and an additional location at 7529 Eglinton Ave. East to prevent further spread.