The owners of the Utah coal mine where nine miners were killed in a cave-in and subsequent rescue effort knew in the months leading up to the disaster that the mine had serious structural problems, according to a report in the Salt Lake Tribune on Thursday.
According to documents obtained by the Tribune, mine co-owner Robert Murray knew of a severe bounce on March 10 that forced the evacuation of miners and equipment.
A “bounce” is an event where the pressure of the mountain bearing down on pillars of coal in the mine cause coal to explode from the roof and walls of the mine shaft.
"The mine started taking bounces and had to retreat the equipment very quickly. There were no injuries and all equipment was recovered out of the area," the mine’s operator, UtahAmerican Energy, told the Crandall Canyon co-owners, Intermountain Power Agency, in a March 21 meeting, the Tribune reports.
Murray had said at the time of the August, 2007 collapse that he had no knowledge of the bounce. According to the Tribune report, mine operations moved farther south from the area of the March bounce. The miners killed in the August collapse were working in an area about 900 feet away from the site of the March incident when the mine collapsed.
According to the Tribune report, the March incident was never officially reported to federal regulators, as required by law.