Nickel mining giant Vale will be pulling something new out of the ground in Sudbury — fish.

Vale has already been growing tree seedlings in a green house deep in the warm underground for decades, but now the company wants to raise rainbow trout right next to them.

The trees are planted in Sudbury to re-green the landscape scarred by mining. And the fish will be put into lakes “that may have been stressed by mining activities in the past,” said Glen Watson, Vale's senior environmental specialist.

“Northern Ontarians love their fish. Sudburians, in particular, love their fish. We have a lot of lakes to put them in.”

Underground heat helps fish grow

Vale has spent the past five months raising Rainbow trout in an above-ground facility. On Thursday it released 4,000 fish in the Onaping River. Now that the system is tested, the project will begin underground at Vale’s Creighton mine.

“Growing fish in northern Ontario is extremely difficult because you have to heat the water,” Watson said. “And it costs you money to heat the water.”

But deep below the earth’s surface, that heat is naturally occurring and plentiful.

Watson said there's another upside: the waste from the fish will be used as fertilizer for the tree seedlings, replacing the usual chemicals.

To assist with the project, Vale enlisted Manitoulin Island aquaculture expert Mike Meeker, who said conditions underground are perfect for fish farming. He added that the greenhouse lights used for the trees will work just fine for the fish.

Watson said, as far as he knows, the project is a first.

“We are miners by trade,” he said. “We are certainly not used to growing fish.”