David Hughart, the former President of Massey Energy’s Green Valley Resource Group, will plead guilty to federal coal mine safety crimes.

Hughart is a big catch for federal prosecutors, as they move up the Massey corporate ladder in their quest to charge those executives responsible for the 2010 coal mine explosion that killed 29 workers.

Hughart is the highest-ranking official charged to date in an ongoing federal investigation of Massey.

Federal officials alleged that Hughart and others at Massey conspired to violate health and safety laws, then conceal those violations by warning mining operations when Mine Safety and Health Administration inspectors were coming.

The alleged criminal conspiracies involved not just Hughart’s Green Valley group but also other Massey mines, and spanned a period from 2000 through March 2010.

“Miners deserve a safe place to earn a living,” said U.S. Attorney Booth Goodwin. “Some mine officials, unfortunately, seem to believe health and safety laws are optional. That attitude has no place in the mining industry or any industry. Today’s charges reinforce that urgent message.”

The Charleston Gazette reported that internal Massey documents, made public as part of lawsuits against the company, show that Hughart was fired on March 19, 2010.

Hughart failed a random drug test and “seemed to be having financial difficulty,” according to the documents, which were unsealed by a court action brought by The Charleston Gazette and NPR News.

The Gazette reported that Massey auditors alleged that Hughart hired his son, promoted him to an $89,000-a-year job, and gave him a company truck to drive.

The audit report, filed in Kanawha Circuit Court, also alleged that Hughart received $150,000 in kickbacks between May 2008 and March 2010, by having a Massey contract firm fake invoices for work that was never performed, the Gazette reported.