Dane Gibson
Northern News Services

NNSL (May 21/99) - Arsenic dust continues to collect around Yellowknife and even in small concentrations, it may be cancer-causing.

"It is now known that the health risk for humans is greatest at higher levels but arsenic is a "non-threshold" carcinogen and even levels (below the Ontario standard) presents a risk of causing cancer," a Department of Resource, Wildlife and Economic Development report released Thursday said.

The report, called the Yellowknife area Air Quality Monitoring executive summary, uses Ontario's standard for measuring arsenic levels -- which is 0.3 micrograms per cubic metre of air.

Dust samples are collected in downtown Yellowknife every six days. Besides monitoring for lead and sulphates, they measure arsenic levels.

From 1985 to 1997, arsenic has been recorded at varying levels in the air every year. Air Quality programs coordinator, Jim Sparling, said the data doesn't indicate a serious public health risk because the levels recorded are low.

But, he said, the system at Giant must be updated to eliminate any danger.

"As long as the roaster operates, there will be arsenic in our environment," Sparling said.

"The existing control equipment is as good as it's going to get -- it's at its maximum efficiency. The real answer is to get into something that eliminates (arsenic trioxide and sulphur dioxide) emissions entirely."

For the safety of Yellowknifers, maintenance of the mine is critical while it continues to operate. The report said that arsenic levels in Yellowknife over a 24-hour period spiked above the Ontario standard twice, both times were in 1988 and coincided with pollution control equipment malfunctions at Giant Mine.

Ecology North director, Andrew Spalding, said there are relatively low levels of arsenic being recorded today only because the mine is producing less gold than it has in the past.

"From the data I've looked at, there's high levels of arsenic in the soil all around Yellowknife," Spaulding said.

"This has to be addressed now because we're polluting not just the mine but the town site. When there's high levels of arsenic in the playgrounds where children play, people should be concerned."