An audit of the Mine Safety and Health Administration shows it's implemented more than half the 100 internal changes recommended after a 2010 explosion killed 29 West Virginia coal miners.
The Department of Labor's Office of Inspector General says MSHA's efforts to address its own shortcomings began well before an internal review report was released in March of 2012.
Barring unforeseen circumstances, it says MSHA is on track to implement the remaining 44 changes as expected. It says MSHA administrators meet weekly and at the highest levels to keep on the timeline. But MSHA chief Joe Main says he can't set deadlines for every change because some factors are beyond his control. Main says the actions so far have made U.S. mines safer than ever; 2011 was the safest year on record.