New sewers, old asbestos: busy summer for Dawson City

Construction crews will be digging up whole blocks of sewer and water mains in Dawson City this summer, so the town is partnering with the Yukon government on a large-scale communications plan to make sure tourists and residents stay informed of the progress, and of what's being done to protect them from asbestos contained in the rock that will be unearthed.

"There's going to be a lot of activity happening, and based on the results of the air sampling, some of the work sites will probably be barricaded and people will be in suits," said Trina Buhler, project manager for the City of Dawson.

"We want the community to be aware of what's happening and that this is an occupational hazard only. It's not a hazard to the public."

When the existing sewer and water systems were installed in 1979, the trenches were filled with rock that contained naturally-occurring asbestos. That rock will be dug up as construction proceeds over the next two years.

"As far as we know, the asbestos materials occur in rock that is in Moosehide Slide," said Leyla Weston, the outreach geologist for the Yukon Geological Survey.

"The other thing we understand is there were pits, in the '70s and presumably earlier, and they used that local rock which contained asbestos materials as fill and ballast. So you're introducing naturally-occurring asbestos from the rock north of town, and bringing it into the town of Dawson City proper."

Weston says studies done in the 1980s show the actual levels of asbestos are "very, very low," with concentrations of up to one per cent of asbestos fibres in the rock.

"But if you are to walk the streets of Dawson you won't see that rock exposed at the surface as you would have in the '70s," said Weston. "The fill is now buried, so it poses no health risk, and the roads have since been covered with a very nice, benign, and pretty quartz gravel."

Asbestos is classified as a class one carcinogen. The hazard occurs when rock is disturbed and fibres are released into the air and inhaled.

"While we were preparing for [the capital projects in Dawson], Community Services learned about the potential for this naturally-occurring asbestos," said Aisha Montgomery, communications director for the Department of Community Services. "So we hired an industrial hygienist to help us develop an asbestos control plan."

Work to begin in spring

Four major infrastructure projects will begin as early as May. Almost 800 metres of sewer lines and water mains will be replaced on Fifth Avenue and Front Street, and construction will start on a new York Street lift station, and drinking water treatment plant at the corner of Fifth Avenue and Turner Street. Most of the work will be covered by federal funding.

Companies bidding on the Dawson projects will be responsible for meeting the plan's requirements, and the standards of the Yukon Workers' Compensation Health and Safety Board.

The Department of Community Services and the City of Dawson have hired a local contractor to keep the community informed of construction locations, detours, and mitigation efforts.

"It's a necessary thing. It's our water, it's our sewers, these essential services and they need to be upgraded just to keep everybody safe and keep on top of things," said Buhler.

Dawson is notoriously busy in the summer, and officials want to make sure the local population continues to have proper access to town, and tourism isn't affected.

Up-to-date information will be communicated through announcements on local radio and TV, road signs, community meetings and a dedicated Facebook page.

The first public meeting was held at the Tr'ondëk Hw ëch'in Community Hall last week. Thirty to 40 people showed up to hear presentations from officials, including Chief Medical Officer of Health Brendan Hanley, Dawson project manager Rick Kent, and an industrial hygienist from Red Deer, Alta.

Buhler says most of the concerns were over disruptions to the town, not asbestos.

"A lot of the contractors that were there were completely aware of this happening, or that this fill was used back in 1979 and the concentrations were so low. This has just always been a thing here," she said.

There's never been systematic testing for asbestos in the air in Dawson City. Daily samples taken at work sites over the next two years will be consolidated and applied towards projects in the future.

"What plans do we have to put in place in the future? Can we map this? While we're digging, why not gather some information, right?" said Buhler.

"It's totally reasonable to ask for that additional component, just so we're aware and we can keep the community and our workers safe."