The City of Abbotsford will have to continue dredging asbestos out of the Sumas River in 2011.
The naturally occurring material is carried from a watercourse in the U.S., and settles in the river sediment. The river has been dredged annually for flood control, but the presence of the carcinogen means city workers must take special measures, including protective gear for workers.
“WCB commended us on the job we did (last year),” said Jim Gordon, city general manager of engineering.
Wet asbestos is not a known hazard, but if it is inhaled the substance can cause cancer. There is a chance that if the Sumas River waters flooded, the material could spread, and as it dried, people could be exposed to health risk.
“There’s a chance it could be dangerous,” said Gordon. “If there’s a chance, we have to take the proper measures.”
In 2009 officials from the U.S. Environmental Protection Agency warned the city about the asbestos. There is a Sumas Mountain in Washington state, and a slide on the mountain has exposed naturally occurring asbestos. It is picked up by Swift Creek, which drains into the Sumas River and ultimately the Fraser River.
Asbestos levels were actually higher in the Sumas River than in Swift Creek last year.
Gordon said the city has also been in touch with U.S. officials, to see whether they can stop or reduce the amount of asbestos.
According to a city press release, sampling of the sediments dredged from the Sumas River in 2010 showed similar trends to 2009 results.
“Testing indicated that sediments from the dredging locations closer to the Canada-U.S. border contained higher asbestos levels than locations further downstream,” said Mayor George Peary in the release. “Also similar to the 2009 investigation, there was a spike in asbestos levels at the location downstream of the confluence with McKay Creek, however, no contamination was found in McKay Creek.”
Following the results of the sediment testing, Peary sent a letter to the provincial environmental ministry urging them to discuss the matter with the US Environmental Protection Agency and encourage them to employ efforts to minimize the release of the naturally-occurring asbestos sediments in Washington State into the Sumas River.
The dredged asbestos is taken to the Valley Road landfill, and covered with soil.