The State Fire Marshal's Office says the massive explosion at the LEAP, Inc. building was caused when an underground propane line was accidentally severed.

Public Safety spokesman Steve McCausland says the line was cut during the installation of one of four bollards, that were drilled into the ground near the building, on Tuesday, September 10th. Investigators with the State Fire Marshal's Office have concluded that one of those posts severed the line, causing the propane leak that led to the massive explosion, leveling the building. The explosion happened six days later, on September 16th, and killed Farmington Fire Captain Michael Bell, injured six other Farmington firefighters, as well as building maintenance supervisor Larry Lord. The six firefighters were treated in area hospitals and released, while Mr. Lord remains hospitalized.

Fire investigators say the bollard work was done by Techno Metal Posts of Manchester, Maine, who drilled the ten foot long posts into the ground, about five feet away from the building, in the paved parking lot. Each post was sunk about seven feet, leaving three feet above ground, and were placed there to protect an outdoor air conditioning unit. The propane line was buried beneath the parking lot at a depth of about 2 1/2 to 3 feet, and connected to an outside propane tank, which was located at the rear of the property. It entered the building through a basement wall at the rear corner.

Officials say the parking lot was paved last summer, after the propane line was installed. The metal bollards are about 4 inches thick, but each had a 10 1/2 inch wide auger head that allows the post to be drilled into the ground. It was the auger head that severed the propane line, which was encased in a plastic protective sleeve.

On Friday, September 13th, Larry Lord discovered that the 500 gallon propane tank was empty. He called C.N. Brown, who filled the tank just after noon. The following Monday, a second maintenance worker felt dizzy after being in the building a short time, and he and Lord discovered that the propane tank was empty, once again. Lord called the fire department and then he opened windows and doors and told the staff members to leave. Some firefighters arrived at 8:13 am. and joined Lord in the basement to investigate the source of the leak, while others went elsewhere in the building to make sure everyone had evacuated. The explosion took place at 8:28 a.m.

While the source of the leak has been identified, officials cannot determine what sparked the explosion. Some possible sources of ignition could be the disruption of electricity, a light switch, furnace, or static. Fire officials say no charges are expected in this case. Among the agencies assisting in the investigation were the Farmington Police and Fire Departments, Maine State Police, the federal bureau of Alcohol, Tobacco, Firearms, & Explosives, the Maine Attorney General's Office, the Maine Fuel Board, and the Public Utilities Commission, which oversees the Dig Safe program.

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