A plume of sediment deposited in Quesnel Lake by the collapse of Imperial Metals’ Mount Polley mine tailings dam is changing water quality as it shifts, according to the Interior Health Authority.

The shifting sediment has reinforced water-quality concerns among Likely-area residents.

Although test results have shown water from Quesnel Lake is safe to drink, Interior Health told residents who notice increased sediment or cloudiness in their water they “may wish to consider alternate sources for their water.”

Likely resident Judy Siemens said the plume — a “funny” green colour similar to that of a glacial lake — comes and goes, sometimes over significant areas of the lake.

“We are not drinking the water yet,” she said. “Most people on the lake aren’t drinking their water yet.”

Likely resident Peggy Zorn, who lives beside the Quesnel River, said it has been murky since last weekend, which is very unusual as the river normally runs crystal clear.

As for the notice to consider alternate sources of water for residents who find their water running cloudy, she described it as stupid. “What other water sources?” quipped Zorn, who with husband Gary owns Ecotours-B.C.

Despite a Likely community meeting hosted by provincial officials Tuesday evening on the status of water quality, Zorn said residents are getting frustrated and described a lack of clear-cut answers as “bizarre.”

B.C. Ministry of Environment spokesman David Crebo said in a written statement officials were out on Quesnel Lake Tuesday taking samples at various depths and locations to help define the location of the sediment plume.

“These samples are arriving at the lab for analysis (Wednesday),” said Crebo.

The latest water quality results released publicly by the environment ministry are from Aug. 13, showing samples from half a metre below surface and eight metres met drinking water guidelines.

Samples were also collected within a suspended sediment plume at 40, 60, and 90 metres of depth in the west arm of the lake. Tests showed the water quality at 40 metres depth and below exceeded some drinking water guidelines and several aquatic life guidelines. Interior Health medical health officer Dr. Trevor Corneil said that earlier testing of water in the sediment plume has shown slightly high copper and iron levels, not surprising since Mount Polley was a copper mine and iron is a very commonly found element in the area.

He said he understands residents’ heightened concerns because of the cloudy water, but stressed the water is safe.

“Any concerning levels of elements in the water, or some of the sediments, are not at concentrations in areas that we have measured, at levels where people draw water from, that are a hazard to people’s health,” said Corneil. “The same for the fish: the fish are not a hazard to people’s health.”

Corneil said residents should never be drinking cloudy water, nor should they drink surface water unless it’s disinfected.

Those are normal precautions that should be taken always, but some residents that have taken their water from Quesnel Lake have not taken these steps in the past, he noted.

He said he would not be surprised to see residents who draw their water from the lake experience cloudy water for the next few months.

An approximately one kilometre-by-500 metre plume of sediment that was initially located at the outlet to Hazeltine Creek on Quesnel Lake has since dispersed and is appearing in smaller pockets of the west arm of the lake, said Corneil.

The sediment has been found as deep as 60 metres in the lake, below where residents draw their water, he said.

The sediments from the tailings dam spill will be mixed with sediments that would naturally be part of Quesnel Lake, added Corneil.

Likely residents have also expressed concerns about lack of cleanup of the spilled tailings.

Zorn wants the sludge in Hazeltine Creek and Quesnel Lake should be cleaned up before winter. If not, she is worried that more tailings will be deposited in Quesnel Lake with the spring melt.

The collapse of a 300-metre section of the Mount Polley tailings dam on Aug. 4 released 10 million cubic metres of water and tailings comprised of finely ground rock containing potentially toxic metals.

Following the collapse of the tailing dam, Imperial Metals CEO Brian Kynoch was asked if he would drink the water, to which he replied: “I would drink the water once the solids come out.”

ghoekstra@vancouversun.com

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