UNION MILLS | A malfunctioning pulley caused the June 24 explosion at a Union Mills grain elevator that killed a worker, according to investigators.
The Co-Op is no longer operating and may have to be rebuilt or torn down because of extensive damage primarily to the roof covering all of the 24 silos in the facility, said John Homan, fire chief of the Noble Township Volunteer Fire Department.
Homan said on the day of the explosion, a conveyor was taking grain from the basement to the top of two silos when a steel shaft on a pulley operating the conveyor came loose.
The heavy steel pulley -- about five feet in diameter -- slid into a concrete wall. Because the conveyor kept operating, the pulley continued to rotate.
The friction from the pulley rubbing against the concrete wall eventually generated enough heat to ignite grain dust in the elevator resulting in an explosion, Homan said.
The grain in two of the silos also caught fire.
"That's where the heat source that ignited the grain dust had came from," Homan said.
James Swank, 67, was on a work platform outside one of the silos when the force of the blast caused him to fall more than 100 feet to his death.
The impact of the blast lifted the concrete roof three feet. When it came down, if cracked many areas of the roof and damaged the perimeter of the roof, said Shawn Lambert, safety manager for Co-Alliance, the owners of the Co-Op.
"You can see the damage around the edges but it's actually still intact," Lambert said about aerial photos taken of the roof.
Lambert said structural engineers will come in next week to determine if the facility can be saved.
He said most of the silos were empty because it's now the growing season and the few silos that contained grain are being emptied to allow the inspectors to go inside.