In its 300-plus page report made public Tuesday, an internal review team, made up of MSHA employees, compiled details as far back as 18 months prior to the explosion that killed 29 miners on April 5, 2010.

It also looked at the effectiveness of the agency’s standards, regulations, policies and procedures in addressing the hazards that caused or contributed to the disaster.

“While there was no evidence linking the actions of MSHA employees to this tragedy, we found instances where enforcement efforts at UBB were compromised because MSHA and District 4 did not follow established agency policies and procedures,” internal review team leader George Fesak said.

MSHA said among its own inspection and plan approval shortcomings was overall noncompliance on the part of its District 4 team in southern West Virginia in following all outlines set forth by the agency for proper processes of inspections, investigations and mine plan reviews.

Officials cited a myriad of reasons for the issues, including inspectors’ lack of experience, insufficient training and inadequate managerial and supervisory oversight and directives system deficiencies.

Inspectors, the review team found, did not consistently identify deficiencies in Massey’s program for cleaning up loose coal accumulations, coal dust and float coal dust and its staff did not effectively utilize the producer’s examination books to determine continued negligence.

The extent of Massey’s noncompliance with rock dust standards near belt conveyors was also not identified by federal inspectors, nor were significant deficiencies in UBB’s ventilation and roof control plans.

“District 4 personnel did not intervene as Massey manipulated MSHA procedures to avoid complying with reduced standards for respirable coal mine dust and allowed the operator to significantly delay corrective action to reduce miners’ exposures to unhealthy respirable dust concentrations after overexposures were identified,” the agency’s evaluators added.

Inspector experience was just one of the issues MSHA pointed to as an impetus for the shortcomings.

Another was a lack of resources stemming from budgetary constraints going as far back as 2006 that resulted in “significant reductions in the inspection workforce”.

While the agency was making efforts to re-establish those staffing levels, the levels of workforce and total experience had not been fully regained by the time of the 2010 blast.

MSHA also looked at management turnover as a contributing factor to its shortcomings, noting that between June 2003 and July 2004, it had four individuals temporarily assigned to act as District 4 district manager at various times.

Moreover, due to that turnover, the associated supervisors with jurisdiction over the district, including the UBB mine, did not conduct adequate reviews of the mine’s inspection reports, identify significant deficiencies or recognize that some portions of the Massey mine had not been inspected.

According to MSHA’s accident investigation team’s findings released last December, then-owner Massey Energy (Massey was acquired by Alpha Natural Resources in June 2011) violated basic safety standards and failed to prevent or correct numerous hazards that ultimately caused the explosion.

It also used advance notice of the presence of inspectors and miner intimidation to hide violations.

“I directed my staff to conduct the most comprehensive internal review that has ever been done at MSHA and I feel confident they have achieved that objective,” Assistant Secretary of Labor for Mine Safety and Health Joseph Main said.

He said that the final report released Tuesday was the result of nearly two years of efforts, interviews with approximately 90 current and former MSHA employees and the examination of more than 12,500 pages of documents.

“MSHA is responsible for its actions and will address each of the problems the team has specifically identified,” Main said.

“We take the deficiencies and recommendations outlined in this internal review extremely seriously.

“In fact, shortly after the tragedy at UBB, we began aggressively implementing a number of corrective actions, some of which directly address the internal review team’s findings.”

Some criminal activity related to the UBB blast has come to light in the time since investigations commenced into the incident’s cause.

One former UBB security director was convicted of lying to federal investigators and ordering evidence destruction and another employee was sentenced to jail time for faking a mine foreman license and lying to federal officials.

On February 22, a UBB mine superintendent was also charged in a criminal information for conspiracy to defraud the US by engaging in a conspiracy to give advance notification of mine inspections, falsify examination record books and alter the mine’s ventilation system before federal inspectors were able to inspect underground.

Facing a jail sentence of up to 25 years, the individual received three years imprisonment plus supervised release and a $US20,000 fine.