HARRISBURG, Pa. (Legal Newsline) - For the first time during his time in office, Pennsylvania Attorney General Tom Corbett has filed criminal charges over a fatal accident at a coal mine.

After stating its case against David and Steven Zimmerman and Jeffrey Klinger to a grand jury, Corbett received the go-ahead on Wednesday to file charges of involuntary manslaughter in the 2006 death of Dale Reightler.

"Safety procedures are placed in mines for a reason," Corbett said. "Mining is a dangerous business, and protection of miners' safety and well-being should be a mine operator's primary concern."

Two separate accidents at the Buck Mountain Mine led to charges. The first occurred on Dec. 1, 2004, and Corbett says R&D Coal Co., which owns and operates the Buck Mountain Mine, falsely reported that to the Department of Environmental Protection that an explosion happened because of an air or water line rupture. The company also said four minors were slightly injured.

Instead, the grand jury determined that a methane ignition caused the explosion, and two minors were seriously injured. It also charged that other employees were instructed to remain silent about the methane ignition.

David Zimmerman is the mine's owner and operator, while Steven Zimmerman is the mine's foreman. They were also charged in the fatal accident, as was miner Jeffrey Klinger.

Klinger, 42, triggered the detonation of an Oct. 23, 2006, explosion that killed fellow miner Dale Reightler, the grand jury said.

Dangerous accumulations of methane caused by inadequate ventilation, failure to conduct pre-shift inspections, failure to follow proper blasting protocols and failure to monitor methane levels caused Reightler's death, it is alleged.

Klinger is alleged to be responsible for not following the proper safety procedures prior to detonating the explosion.

The Zimmermans are charged with: Involuntary manslaughter, which carries a possible five-year prison sentence; two counts of causing or risking a catastrophe, which carry a possible 17-year sentence; recklessly endangering another person (two-year maximum); obstruction of justice (two-year maximum); criminal conspiracy (two-year maximum); and violations of the Anthracite Coal Mine Act (one-year maximum.

Klinger is charged with involuntary manslaughter, causing or risking a catastrophe, recklessly endangering another person and violations of the Anthracite Coal Mine Act.

The Morning Call of Allentown reported that Corbett filed the charges, a first for him over a fatal mining accident, because the state DEP and U.S. Mine Safety and Health Administration had found violations of the Anthracite Act. It also said MSHA fined the company approximately $900,000 for the violations it said resulted in Reightler's death.