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Oct 12 (Reuters) - Canada's Enbridge Inc on Thursday said a 30-inch natural gas pipeline in northern British Columbia has become operational after being shut down due to a fire in an adjacent line, which led to supply disruptions in the U.S. state of Washington.
Enbridge, Canada's largest pipeline operator, isolated and depressurized a 36-inch (91-cm) pipeline, which carries gas to the Pacific Northwest, after it ruptured on Tuesday evening causing gas to ignite. An adjacent 30-inch pipeline was also depressurized for safety.
The Canadian regulator, National Energy Board (NEB), on Wednesday night approved the restart of the 30-inch line, which runs parallel to the impacted line, after a comprehensive integrity assessment, Enbridge said.
"Following the NEB order, Enbridge initiated our restart plan to safely and gradually bring the line's pressure up to approximately 80 percent of normal operating capacity. Natural gas is now safely flowing to our customers through the single line," the company said in a statement.
Enbridge, however, added that it did not have an estimate on how long it will take to complete the investigation process, or for repair and return of the impacted 36-inch line back into service.
The incident forced various refineries in Washington to shut or curb operations as natural gas supply to the facilities was disrupted, which led to a surge in fuel prices in the Pacific Northwest region and across the West Coast.
The rupture occurred near the city of Prince George in British Columbia's northeast. About 100 people were evacuated from their homes in a nearby Aboriginal community on Tuesday as a precautionary measure. There were no injuries. (Reporting by Karen Rodrigues and Vijaykumar Vedala in BENGALURU Editing by Kenneth Maxwell)