The NEB’s directives are contained in the pipeline incident report on an 18-in Westcoast (now Duke Energy Gas Transmission) gas pipeline rupture that occurred between Fort St John and Taylor, BC, on 15 May, 2002. The pipeline break released approximately 3.73 million cuft of sour gas containing 0.41% H2S. There were no injuries, but the escaping gas resulted in the evacuation of nearby residents, including a caravan park. The NEB’s investigation found that the rupture was probably caused by a shock wave or impact created after a hydrate, or ice plug blockage, was released by a differential pressure in the line. The sending barrel pipe where the rupture occurred was in a weakened condition due to accumulated elemental hydrogen and had been idle for two years, allowing fluids to accumulate, the NEB says. In addition, the ruptured pipe didn’t meet the “toughness requirements” of the Canadian Standards Association design standards. Westcoast also didn’t have the necessary documentation for the material and design of the sending barrel. The NEB said there was also a lack of communication between Westcoast’s incident commander and the Taylor Fire Department’s field incident commander. Westcoast had starting advising residents by phone to remain in their homes until the situation had been resolved. But residents had already started evacuating the immediate area. The Taylor Fire Department chief  after seeing the direction of the gas plume  ordered any remaining people in the area downwind from the leak to also be evacuated. It took about two hours and 20 minutes after the rupture occurred for the field incident commander to declare the situation safe. The NEB directed Westcoast to review its emergency response plan, including the handover of incident command, with all first-responders in the Fort St John area. . This story courtesy of EnviroLine, Canada, enviroline@shaw.ca.