Massachusetts gas blasts kill 1, injure 10

Multiple explosions on a natural gas distribution line north of Boston operated by a Nisource subsidiary killed one and injured 10 others yesterday.

The explosions in Merrimack County, Massachusetts, destroyed several homes and ignited more than 60 structure fires that were extinguished as of this morning, the Massachusetts Emergency Management Agency (MEMA) said.

NiSource subsidiary Columbia Gas of Massachussetts had no immediate comment on the cause of the ruptures. MEMA yesterday said gas line over-pressurization may have been the cause.

Columbia Gas in a statement today called the incident a "tragic accident" and said it was mobilizing crews to visit each of the 8,600 affected customers to shut off individual gas meters and conduct safety inspections.

A joint investigation between local, state and federal agencies, including the National Transportation Safety Board (NTSB), is in the beginning stages, according to MEMA. Industry group the American Gas Association today said subject matter experts from the NTSB, the US Pipeline & Hazardous Materials Safety Administration and state regulatory agencies are investigating.

Once utilities secure the affected areas, the state will work with the federal government to investigate the incident and "hold people accountable for their actions," Massachusetts governor Charlie Baker said.

Ruptures on local distribution lines typically do not affect regional spot natural gas prices as they flow to a limited number of end-users. Prices for delivery today at Algonquin Gas Transmission Citygates, which serves New England, averaged $2.71/mmBtu, at a 23¢/mmBtu discount to the Henry Hub.

Local distribution company Columbia Gas of Massachusetts is not affiliated with midstream company Columbia Gas Transmission, which in 2016 became a subsidiary of TransCanada.