The Lower Similkameen Indian Band says it is considering seeking an injunction to stop work at the Copper Mountain Mine near Princeton, B.C., until a third-party investigation can be conducted into the spill and clean-up.
A discharge box plugged and overflowed on Dec. 10, spilling 500 tonnes of mine slurry into a treed ravine and into Wolf Creek, which flows into the Similkameen River.
Chief Keith Crow says the river is the "lifeblood" of his band and he's concerned about long-term effects on the water his community uses for drinking, fishing and farming.
Interior Health issued a do-not-use water advisory that was lifted for most of the area on Tuesday when the water was deemed safe.
Copper Mountain president and CEO Jim O'Rourke says two barriers meant to contain tailings overflowed but the company has installed a larger barrier to prevent future spills.
He says the slurry only reached the upper part of Wolf Creek on the mine's property and workers installed silt curtains to prevent tailings from flowing further down.
O'Rourke says workers immediately contacted regulatory authorities and the Ministry of Environment has been overseeing the spill clean-up and prevention efforts.
But Crow's band is calling for a full independent inquiry and environmental review. He's worried the slurry may still flow into the Similkameen River.
"As stewards of the land, we're responsible for everything that happens within our territory and our land. When spills and things like this happen, we need to have a say," he says.
O'Rourke says the Lower Similkameen band has been kept apprised of the clean-up and about 10 band members are employed by the mine.
"We're very sorry it happened, but it was a mistake," he says, adding that "unfortunately" existing barriers protecting the ditch weren't sufficient and they are correcting that so a spill never happens again.
The Ministry of Environment continues to collect water samples on a daily basis and toxicity tests for rainbow trout and invertebrates conducted immediately after the spill passed with 100 per cent survival, says a spokesman.
Ministry staff are working with the Upper and Lower Similkameen First Nations to co-ordinate a discussion about the cause and impact of the spill and next steps, the spokesman says.
Mining companies have faced increased public scrutiny since the massive Mount Polley spill in B.C.'s Cariboo region in August, which released about 25 million cubic metres of water and tailings materials into nearby lakes and rivers.