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Trans Mountain monitoring spill of drilling additive in Coquitlam watercourse

Anti-pipeline group raises concerns about spill in Coquitlam watercourse but Trans Mountain says it was a non-toxic drilling fluid
Water ceremony Fin Donnelly photo
Indigenous leaders held a ceremony at Maquabeak Park in Coquitlam in May, 2021 to express concerns about an oil pipeline being drilled under the Fraser River.

Trans Mountain continues to monitor the impacts of a spill of clay-based drilling fluid in a water course near the Mary Hill bypass in Coquitlam last week.

In a statement, the company reported that approximately one cubic meter of bentonite was “inadvertently released” into a watercourse during horizontal directional drilling (HDD) procedures on Friday (Nov. 19).

The drilling is to install a section of pipe from Surrey to Coquitlam for the construction of the pipeline to Burnaby.

According to the statement, bentonite is a non-toxic clay additive and is commonly used for drilling fluid in subsurface installation operations like HDDs. 

The company stated that it has taken several steps to mitigate the risk of the spill, including:

  • isolating the watercourse both upstream and downstream of the area. 
  • Installing a pump to divert the watercourse around the release location.
  • Dewatering and clean-up in the area and ongoing monitoring by resource specialists.
  • Informing regulatory agencies.

So far there have been no observations of impacts to fish and wildlife, according to the company, but a local group raised concerns about the spill.

In a tweet, the group Protect the Planned Stop TMX noted a flurry of activity on the site on Saturday.

While the spill is outside of Colony Farm Regional Park it is not far from the location of a protest against the multi-million project currently under construction in several stages across the province, including Coquitlam.

Colony Farm Regional Park in Coquitlam is a staging area for a horizontal directional drilling operation under the Fraser River.

Read more information about the Coquitlam leg of construction here.

Now owned by the federal government, the $12.6-billion Trans Mountain pipeline expansion project is slowly making its way from Alberta to the Westridge Marine Terminal in Burnaby.