According to agency data released this week, four of the claimed violations were directly involved with the April 5 explosion that killed 29 miners. The remainder were found to have occurred between January 2008 and early 2010.

Several of the violations related to unreported roof falls. Others included injuries to workers, and two referenced miners seeking to transfer from dusty areas of the mine after contracting black lung disease.

According to the documentation, all of the noted violations were reportable issues.

MSHA said citations were issued because it was not aware of the violations until the audit, which is being conducted in conjunction with the investigation of the UBB explosion.

MSHA declined to provide a formal statement, instead referring ILN to the 52-page documentation for the ongoing audit.

Massey spokesperson Jeff Gillenwater confirmed the existence of the violations to ILN and said the company was reviewing them.

“At this time, we can say that we agree with some citations and disagree with others, but are not prepared to discuss individual citations at this time,” he said.

“Additionally, we have been conducting a more thorough review of our accident reporting at all Massey operations. This review remains ongoing.”

United Mine Workers of America spokesperson Phil Smith told the Associated Press this week that the union thought there was “no surprise” that the company was found by federal officials to have unreported incidents.

"We've been hearing stories about this a long time. This is not the stuff of rumors, this is the stuff of fact."

Earlier this week, MSHA announced it had issued $US542,400 in fines to Massey subsidiary Cumberland Resources for an August 2009 rib roll fatality.

The penalties assessed to Big Laurel Mining, part of the Cumberland umbrella that Massey acquired last year, stemmed from five contributory violations, two of them flagrant.

The August 20, 2009, incident killed electrician and repairman William Parrott, a 33-year mining veteran.

He was preparing to set timbers in the mine’s No. 4 entry under the brow of the right rib when a section fell and crushed him.

Federal officials found that a combination of factors played a role in the fatality, the first being that the operator did not utilize a sightline or other directional control to maintain the projected direction of mining progress.

Additionally, MSHA found that Big Laurel failed to follow the mine’s approved roof control plan and also failed to perform adequate pre-shift and on-shift examinations.

Finally, investigators said the operator failed to adequately support the mine’s rib.

The sightline issue and failure to adhere to the approved RCP each are considered by the agency to be flagrant violations and carry fines of up to $220,000 each.