Sediment samples taken on Aug. 10, 2014, from the mouth of Hazeltine Creek and near Raft Creek in Quesnel Lake show that the sediment poses no human health risk.
The results, however, show sediment exceeds B.C. guidelines for sediments and contaminated sites regulation standards for copper and iron and may pose adverse effects on aquatic life.
Three samples were collected Aug. 10 from near the mouth of Hazeltine Creek and Raft Creek. Two samples were from within the impact zone and one sample was from the undisturbed impacted lake bottom.
Copper levels exceed three standards including the contaminated sites regulation sediment quality criteria, the Canadian Environmental Quality guidelines (CCME) for the protection of environmental and human health, and B.C.’s working sediment quality guidelines.
Iron for all three samples exceeded the B.C. working sediment quality guidelines.
Often areas where mines are located have elevated levels of metals, meaning naturally occurring metal concentrations are often much greater in this region than elsewhere in the province. Scientific evidence tells us that the metals are not likely to readily move from the sediment into the water, and are therefore not likely to present a risk to future water quality.
Leachability tests, to be conducted in the next few days, should confirm this.
These test results have been shared with local First Nations, the First Nations Health Authority, Interior Health and the Cariboo Regional District.
Interior Health continues to assess sample results provided by the ministry for any potential human health risks.
These results provide further reassurance to the decision to partially rescind the “Do Not Use” to the impact zone involving Polley Lake, Hazeltine Creek and a small part of Quesnel Lake.
This order will remain in place for a longer timeframe as work is completed to stabilize Polley Lake and mitigate any further unexpected release from the tailings pond.
Long-term monitoring and remediation will continue in the affected areas.
A comprehensive environmental impact assessment and action plan was submitted by Mt. Polley Mining Corporation to the Ministry of Environment yesterday as required in the Pollution Abatement Order issued on Aug. 5.
Once the ministry thoroughly reviews and approves these documents, they will be publically posted online.
Going forward, updates will occur as new information becomes available.
More information regarding response to the Mount Polley mine incident can be viewed here: http://wwwt.env.gov.bc.ca/eemp/incidents/2014/mount-polley.htm.