A blast at Lafarge Canada’s Sumas Mountain quarry triggered a landslide in late January that led to a stop-work order at the site and triggered a series of further assessments by provincial officials.
On Jan. 26, Lafarge Canada conducted what it called a “controlled blast” on a ridge on the eastern edge of its Ward Road quarry.
The explosion sent soil and rock tumbling down a vegetated east-facing slope. The resulting scar of what appears to be rock and mud is now clearly visible from Sumas Prairie and extends dozens of metres down into the ravine below.
The incident wasn’t publicly disclosed until a reporter from The News noticed the anomaly on the hillside last week.
But officials from the province’s Ministry of Energy, Mines and Petroleum Resources have been at the site multiple times, and ordered a stop-work order restricting further blasting in the area.
The ministry says an assessment report conducted by a Lafarge consultant found the debris from the landslide stopped about 70 metres away from a creek in a ravine below the site. All of the debris remains within the mine boundary.
The consultant found the “main landslide deposit appears stable.” But further work has ceased pending assessments on the area. Ministry officials have confirmed the consultant’s conclusions, the province says.
The province said the quarry operator has removed material from the top of the area to reduce the potential for another slide to tumble down the slope. The province says two rows of fencing have been placed beneath the slide to catch any tumbling soil, and “straw matting was placed on the upper portion of the slide to help prevent erosion.”
The stop-work order will remain in place until the ministry reviews a design plan for the site, the province says.
The Conservation Officer Service was set to assess the situation this week, the Ministry said.
The incident comes less than a year after a blast at a Chilliwack quarry triggered a landslide that forced the evacuation of three homes.
A spokesperson said in an email that the ministry is “initiating a review of the blasting certification scheme this year.”
