No charges to be laid against Vale after investigation of potentially toxic slag run-off

Environment Canada has decided not to lay charges against Vale for potentially dangerous run-off leaking from its Sudbury slag piles.

But the mining company is currently installing a new system for controlling the slag seepage, work it says is unrelated to the government investigation.

Environment Canada refused an interview with CBC, but said in a statement that it began investigating contaminated water coming from the Sudbury slag pile after a complaint from the public in 2012.

Court documents filed to obtain a search warrant for Vale offices in 2015 allege that someone discovered green foam in a creek near the slag piles on Big Nickel Mine Road that had high levels of nickel and other metals.

Those documents also allege that the mining company was aware of toxic run-off from the slag piles as far back as 1997 and that Vale officials were uncooperative when contacted by government investigators. 

Environment Canada says after receiving the complaint in the fall of 2012, it directed Vale to take immediate action, file a report detailing the measures taken to better control seepage from the slag, which it says the company did.

The federal agency also says Vale has been required to file reports every three months since showing test results for waterways surrounding the slag area.

After years of saying the investigation ongoing, Environment Canada now says it is closed, with no charges to be laid, but no explanation was provided to CBC. 

Vale began work this spring on a new reservoir and drainage system designed to better contain run-off from the slag piles following rain showers or spring melts.

Residents of Sudbury's west end were notified of blasting and that work is expected to continue into 2020.

Vale had initially agreed to an interview with CBC for this story, but then decided to provide a statement instead.

The statement says that the company first became aware of the seepage issue in 2012 and took immediate steps to contain and divert the water.

"Importantly, at no time was the community at risk as the water had no connection to any of the city's drinking water sources," reads Vale's statement.

The company's statement also says that "well before" this specific incident, engineering studies were underway to better control water running off the slag piles, which have resulted in the construction currently underway.

"Our focus is on continuous improvement  as circumstances change we adjust our plans accordingly, as evidenced by our current efforts," Vale says in a statement.