Crews extinguish a fire after a gas explosion in Lawrence Thursday. (Scott Eisen/Getty Images)
LAWRENCE (24/7 NewsSource/WBZ-AM) -- U.S. Senators say the pressure was 12 times higher than it should have been ahead of gas explosions last Thursday.
Edward Markey and Elizabeth Warren cited federal regulators' briefings Monday. They say the pressure was high when the natural gas was traveling through Lawrence, Andover, and North Andover.
The Boston Globe reports that the senators are requesting more details from Columbia Gas to determine if work being done in the area was part of the cause for the emergency.
"It is imperative that the people of the Commonwealth are provided an understanding of what caused this disaster and how you responded to it, in order to ensure that we never again face a similar tragedy," the senators' letter read.
Meanwhile, gas service may not be restored to the Merrimack Valley residents for weeks. Those who evacuated from Lawrence, Andover, and North Andover were allowed to return home on Sunday, and electricity was restored to all area homes and businesses.
Columbia Gas is working to replace the 48-mile cast iron and bare steel pipeline system.
(© Copyright 2018 TTWN Media Networks LLC. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)