Remediation of a Settlement and Heave Anomaly on a Pipeline in the Northern Region of Canada – an Update

ABSTRACT: The first completely buried oil pipeline in the discontinuous/sporadic permafrost zone of Canada was constructed in the winters of 1983 and 1985. Since 1989, settlement and heave have been detected along the pipeline at a particular small creek crossing. In 2014, a borehole geotechnical investigation and assessment were completed. Subsequent monitoring revealed that the pipeline continued to experience strain which eventually caused a wrinkle in the pipeline. In February 2017, a section of pipeline approximately 90 m long, including the wrinkle, was replaced. During the replacement work, additional thermistors and piezometers were installed at the site, including a pipe thermistor directly on the pipeline to provide ongoing monitoring. This update on the original paper presents the monitoring information between 2014 and 2016, findings of the replacement work, details on the pipe wrinkle and subsequent monitoring.