The U.S. Department of Labor’s Mine Safety and Health Administration (MSHA) announced that, as of Dec. 31, 2013, the agency had addressed the 100 recommendations published in a March 2012 internal review report, meeting the specific timetables and deadlines it had set for implementation of each recommendation. That report examined the agency’s actions in the months leading up to the April 2010 Upper Big Branch Mine explosion, which killed 29 miners, injured two and led to sweeping changes in mine safety.

“The internal review was designed to identify shortcomings so that we, as an agency, could take necessary actions to improve mine safety and health,” said Joseph A. Main, assistant secretary of labor for mine safety and health said in a statement. “The result was one of the most comprehensive internal reviews in MSHA history, and the most extensive improvements at the agency in decades.”

In June 2012, MSHA began posting on its website quarterly updates of the corrective actions that had been completed. The agency, however, did not wait for the internal review team to publish its findings and put in place a number of administrative, organizational and regulatory reforms in the immediate aftermath of the tragedy. These reforms included: enhanced enforcement programs, such as impact inspections and a revised pattern of violations process; the splitting of the southern West Virginia coal district into two districts; the upgrading of the Mt. Hope, WV laboratory for better coal dust and gas analyses; reorganization of the Office of Assessments, Accountability, Special Enforcement and Investigations to better manage and support MSHA’s enforcement programs; and publication of final regulations on the maintenance of rock dust, examinations in underground mines and the pattern of violations program to rein in chronic violators.

The full press release can be found at MSHA’s website.