LAWRENCE, Mass. — State regulators cited Columbia Gas at least seven times for a variety of safety violations, totaling $100,000 in fines since 2010, 25 Investigates has learned.
The violations detailed by the Executive Office of Energy and Environmental Affairs include improper pressure testing of gas lines in Brockton, failure to know the location of a gas main in Attleboro, and not following safety regulations when repairing a leak in Taunton.
Columbia Gas now finds itself under even more intense scrutiny since explosions and fires tore through neighborhoods in Lawrence, Andover and North Andover on Thursday afternoon.
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Now federal investigators want to know if high pressure overwhelmed gas lines feeding homes in those communities. An official cause of the disaster has still not been announced, but experts say investigators will look closely at the points where high pressure transmission lines connect to lower pressure distribution lines.
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"I expect the investigation will start really with a timeline. They'll look at what happened when. What do we know happened at which point in time?" said Michael Ahern, a 30 year veteran of the power industry who now serves as director of corporate and professional education at Worcester Polytechnic Institute.
Ahern and others have compared the series of explosions and fires to another natural gas disaster in 2010 in San Bruno, CA when a larger transmission line exploded, killing 8 people and injuring more than 50 others.
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"What seems similar is when a system is subjected to a pressure that's above its design basis and ultimately more than it can handle, there's a failure," said Ahern.
The incident in San Bruno prompted federal regulators to call for new rules to improve safety, but eight years later, many of those changes have yet to be implemented.
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"Safety delayed is really safety denied in many of these situations," said former NTSB chairman Deborah Hersman who now serves as the president of the non-profit National Safety Council.
"We want to make sure that the best practices, the best technologies and the best design is implemented into the system. That's important for that to happen sooner rather than later," said Hersman.
A spokesperson for Columbia Gas says all questions about the investigation are now being referred to the NTSB.