LIKELY, B.C. -- A drinking water ban that followed a mine tailings spill in British Columbia was mostly lifted Tuesday and fish from the area were declared safe to eat -- the latest signs that health officials believe the spill won't have a significant impact on people or aquatic life.

The tailings dam at the Mount Polley gold and copper mine failed last Monday, sending millions of cubic metres of water and silt spilling into lakes and rivers in a remote area about 600 kilometres northeast of Vancouver.

More than 300 people were ordered not to drink or bathe in their water as the company that owns the mine, Imperial Metals (TSX:III), started cleaning up the mess and the government set out to test what exactly leaked out.

Initial test results came back within drinking-water and aquatic-life guidelines, prompting the local health authority to partially lift the water ban last Friday.

Dr. Trevor Corneil of the Interior Health said most of the remaining ban was lifted Tuesday afternoon, with the exception of Polley Lake, which sits next to the failed tailings pond; an adjacent creek that flows into Quesnel Lake; and a small portion of Quesnel Lake.

"I have no reason to believe that this water was ever exposed to unsafe levels of contaminants from the mine breach," Corneil said during a conference call with reporters on Tuesday.

The area that remains under a water ban is largely uninhabited.

Another major concern has been whether fish that live in or pass through the affected lakes and rivers would be harmed by the mine waste.

Corneil said that based on the water testing and what health officials know about what spilled out of the tailings pond, the fish in the area are safe to eat. He said that assessment doesn't apply to fish located within the area still under a water ban.

"We actually have no evidence there has been any exposure to these fish, and therefore I can say with confidence ... that these fish are safe to eat," he said.

Corneil said even if fish passed through sediment contaminated with heavy metals, they wouldn't be exposed to such toxins for a long enough period of time to pose a danger to humans.

The chiefs in two First Nations communities in the area have said their residents don't trust the government's claims that the fish are safe, so they've opted not to harvest salmon in what would normally be the busiest time of the year.

The leaders of the Williams Lake Indian Band and the Soda Creek Indian Band say they want to see independent testing that examines the fish, not the water.

Some experts have suggested it is still far too early to say for sure what impact the spill will have on salmon in the long-term.

The First Nations Health Authority, which oversees aboriginal health care in B.C., is preparing a program to catch and test salmon to assess the potential impact on human health.

Corneil said the salmon tissue testing would provide "additional reassurance," but he insisted there was no need to wait before giving people the all clear to eat the fish.

The federal Department of Fisheries and Oceans issued a notice last week closing the recreational salmon fishery on Quesnel River and Cariboo River because of the tailings spill, though the closure doesn't apply to First Nations.

The recreational salmon fishing ban remained in effect as of Tuesday afternoon.

The provincial government said water and debris continues to flow out of the tailings pond, though it has "decreased dramatically." The company is building a temporary dyke to block more tailings from leaking out.

The province has said it will be the company's responsibility to pay for the cleanup.