The investigation is ongoing and could take up to 24 months to determine why a section of Columbia Gas of Massachusetts’ pipeline in Lawrence, North Andover and Andover exploded on Sept. 13. The explosion, and resulting fires, killed one man, injured dozens and displaced thousand of residents in the Merrimack Valley communities in the Northeast section of the state.
The National Transportation Safety Board (NTSB) is handling the federal investigation into the explosion. In a Sept. 15 press briefing, NTSB chairman Robert Sumwalt said that the investigation could take 12-24 months to complete. He also confirmed that the NTSB is investigating an over-pressurization of the line, which occurred at about 4 p.m. on Sept. 13.
“We believe that the gas did indeed flow into homes at significantly greater flow rates and pressures,” Sumwalt said. “The real question for this investigation is to answer why this occurred.”
On Sept. 16, Columbia Gas and its parent company NiSource Inc. announced that it was committed to completely replacing the entire 48-mile cast iron and bare steel pipeline system in the towns of Andover, Lawrence and North Andover with state-of-the-art plastic distribution mains and service lines, and modern safety features such as pressure regulation and excess flow valves at each premise.
“This unprecedented event requires unprecedented action,” said NiSource president and CEO Joe Hamrock. “With this incident, a life was tragically lost and thousands of other lives were directly affected. We lost the trust of this community and are 100 percent committed to restoring safety, confidence and peace of mind for everyone in this community. Over time, we hope to earn back the trust we lost during this incident.”
Columbia Gas of Massachusetts is in the midst of a multiyear program to modernize its gas distribution system and replace cast iron and bare steel pipeline systems across the state. The company has since announced the next phase of recovery and replacement activities for the Greater Lawrence Area following the Sept. 13 explosion.
“Many people are still hurting in the wake of last week’s disaster,” Hamrock said. “We owe it to this community to fully address the community’s needs and rebuild your trust in us.”
Hamrock said Columbia Gas’ recovery and replacement plan will:
- Aim to have service restored to all homes and workplaces by November 19;
- Bring immediate help to people who need it most;
- Replace and upgrade appliances and other natural gas equipment damaged in customers’ homes and businesses; and
- Provide the assurance of a safe and modern energy system, installed with the highest levels of scrutiny and accountability.
To assist with the next steps in the recovery effort, Massachusetts Gov. Charlie Baker has activated the National Guard to support delivery of hot plates and provide resources for the assessment team.
“We will return natural gas services as quickly as possible – but our core commitment to safety will underpin these efforts,” Hamrock added. “Services will be restored only after new facilities have been fully inspected, tested and proven safe.”