Pipeline Accident Report - Williams Pipe Line Company Liquid Pipeline Rupture and Fire, Mounds View, Minnesota, July 8, 1986

摘要

Unleaded gasoline under 1,434 psig spewed from an opening along the seam of the pipe. Vaporized gasoline combined with air and liquid gasoline flowed along neighborhood streets. About 20 minutes later, the gasoline vapor was ignited when an automobile entered the area. Following an explosion-like noise, fire spread rapidly along the path of the liquid gasoline. Two persons were burned severely and later died, and one person suffered serious burns. There was substantial property damage and soil and water pollution. The National Transportation Safety Board determines that the probable cause of the rupture at Mounds View, Minnesota, was the failure of Williams Pipe Line Company to correct known deficiencies in the cathodic protection applied to the first 10 miles of line 2N. Contributing to the failure of the pipeline was the susceptibility of the low frequency, electric resistance welded pipe to weld seam corrosion and the Department of Transportation's ineffective inspection and enforcement program. Contributing to the extent of the damages was the failure of the pipeline company to provide adequate direction, through its procedures and training, for its employees to effectively respond to emergencies involving failed sections of its pipeline and the nonavailability of remotely operated valves or automatic shutdown capability on the pipeline.