CHARLESTON, W.Va. -- Half of the coal mines examined in an audit by federal investigators violated rules that require companies to report accidents and worker injuries, according to the U.S. Mine Safety and Health Administration.MSHA said that 19 of 39 mines where it conducted the audits either did not report injuries or misreported the amount of time employees were off from work because of those injuries.Four of those 19 mines have been placed on "potential pattern of violations status" by MSHA, meaning they could face tougher enforcement if they don't improve their safety performance."These results expose an unsettling amount of underreporting at mines that already have troublesome compliance records," said MSHA chief Joe Main. "These audits are an important tool as MSHA scrutinizes its system of operators self-reporting accidents and injuries."Under federal law, mine operators are required to file reports of accidents, injuries and illnesses with MSHA. In turn, MSHA has the authority to inspect information necessary to determine if mine operators are complying with those requirements.Two Peabody Energy mines -- one in Illinois and one in Indiana -- have been fighting MSHA requests for such records. Company lawyers have appealed a judge's ruling that was favorable to MSHA.In a news release issued late last week, MSHA said that the 39 audits revealed a total of 76 injuries that had not been reported or where mine operators had underreported their severity.MSHA said that 47 of those injuries occurred at six separate mines formerly controlled by Massey Energy, and now owned by Alpha Natural Resources.Agency inspectors issued 247 citations as a result of the audits, including 98 for failing to accurately report injuries.MSHA named two of the non-Massey mines involved: Walter Energy subsidiary Maple Coal's Maple Eagle No. 1 Mine in Fayette County, W.Va., and Dennis Creg Yonts' Mine No. 2 in Letcher County, Ky., operated by Vision Coal.Agency officials did not identify the other 11 mines or release the names of the companies that own or operate those mines.MSHA has said it could take as long as four months for agency officials to provide details of the incidents, which the Gazette-Mail requested under the Freedom of Information Act.Reach Ken Ward Jr. at firstname.lastname@example.org or 304-348-1702.