KANSAS CITY, Mo. — The National Transportation Safety Board (NTSB) has released the preliminary report of its investigation into a gas explosion that killed a 5-year-old boy and seriously injured his father and sister in Lexington, Missouri, last month.

The deadly explosion happened just after 7:40 p.m. on April 9, destroying one home and damaging two others.

The 5-year-old boy who died was identified as Alistair Lamb. His father, Jacob Cunningham and 10-year-old sister, Camille Lamb, were both taken to Kansas City hospitals with serious burns.

Gas main that caused explosion was unmarked, report finds

The explosion occurred more than three hours after Alfra Construction, LLC – a drilling subcontractor installing a fiber optic line for Sellenriek Construction – drilled into an unmarked gas main, according to the NTSB.

The investigation says the gas main was operated by Liberty Utilities, a subsidiary of Algonquin Power and Utilities Corporation, which provides gas service to the area.

Five days before the incident, on April 4, the NTSB report says Alfra Construction called Missouri 811 to have any buried utilities in the area marked. Liberty Utilities sent a locator to mark them and reported that this work was finished on April 7.

The gas main that was struck before the explosion was not identified or marked during this process, the preliminary report says.

Only one business evacuated after gas leak reported, NTSB says

Shortly after 4 p.m. on the day of the explosion, an Alfra Construction worker operating the drill felt the drill strike an object, according to the NTSB. The work crew saw and smelled odorized natural gas being released, so the crew’s supervisor called 911 and 811 to report a damaged gas line.

About 20 minutes later, the NTSB said crews from the Lexington Fire Department arrived. Nearly 40 minutes after reporting the damaged line, personnel from Liberty Utilities began arriving and attempted to isolate the leak – but did not succeed in stopping the flow of gas – according to the report.

The report says, at the direction of Liberty Utilities, a business about 15 feet from the leak was evacuated before the explosion.

For nearly four hours, from 4 p.m. to 7:40 p.m., no other nearby buildings were evacuated – including the destroyed and damaged residences, which ranged from 80 to 160 feet from the leak.

The damaged main was eventually isolated around 8:10 p.m., nearly 30 minutes after the explosion, according to the report. ​

The NTSB said its investigation is ongoing.

Future investigative activity will focus on Liberty Utilities, according to the NTSB. Investigators will look into Liberty’s:

  • Responses to 811 requests
  • Leak and repair history
  • Emergency response and isolation procedures
  • Record keeping
  • Pipeline safety management system
  • Operator qualifications
  • Public awareness program

The report says the NTSB will also look into state safety oversight, as well as local emergency response and evacuation procedures.

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