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  1. Apr 2017
    1. Pointed Mountain pipeline

      The Pointed Mountain Pipeline is a 34.2-mile long natural gas pipeline that connects a dehydration plant at Beaver River in British Columbia, with another plant at Pointed Mountain in the Northwest Territories (Landeen, Brandt). The pipeline extends across British Columbia, the Yukon, and the Northwest Territories. The pipeline crosses the Kotaneelee and La Biche Rivers. Construction on the pipeline began January 24, 1972 and the pipeline was completed in March of 1972, but was not in operation. Throughout the construction of the pipeline, scientists worried about the environmental factors of the pipeline, such as permafrost melting, bank instability, and siltation of rivers. The pipeline was built through a permafrost region. Because the natural gas has the ability to melt the permafrost, weights were attached to the pipe to prevent it from surfacing. Scientists were concerned about bank instability due to erosion when the pipeline crossed the Kotaneelee River. Sandbags supported the pipeline in order to increase stability. Drainage pipes were also added to prevent erosion. Scientists were also concerned about the high water levels in the rivers during spring thaw. The pipes were placed in a deep trench, surrounded by concrete to prevent rising of the pipes during flooding. The trench then fills in with water to prevent river overflow. A map showing the installation of the pipeline can be found below:

      Landeen, B. A., and W. C. Brandt. "Impressions on the construction of the Pointed Mountain Gas Pipeline." Environment Canada Fisheries and Marine Service, November 1975. Accessed April 06, 2017. http://www.dfo-mpo.gc.ca/Library/15011.pdf