The first arc fault failure at the Utah plant was on Aug. 9, 2012, according to project documents. Since then, the center has had nine more failures, most recently on Sept. 25. Each incident caused as much as $100,000 in damage, according to a project official.
It took six months for investigators to determine the causes of two of the failures. In the months that followed, the contractors employed more than 30 independent experts that conducted 160 tests over 50,000 man-hours, according to project documents.