The federal Mine Safety and Health Administration has cited four Kentucky coal mines for safety violations. The mines were among 16 nationwide with a history of compliance problems targeted in MSHA's special impact inspections.The mines cited were Exel Mining’s Van Lear Mine in Martin County, Perry County Coal’s E4-1 Mine and two Harlan County mines owned by K and D Mining and D&C Mining Corporation.MSHA singled out two of those mines as examples of egregious safety violations. At the Perry County mine, inspectors found ventilation problems, which could expose miners to the risk of black lung disease or a potential explosion. The mine operator also didn’t maintain the primary and secondary escape, so miners could have become trapped in an emergency.At K and D Mining’s Mine Number 17 in Harlan County, inspectors found numerous problems. The mine operator was allowing combustible coal dust to accumulate along the conveyer belts, which could result in an explosion. The inspectors also noted cracks in the underground mine’s roof, which could lead to a roof collapse.The agency has been conducting the unannounced impact inspections since April 2010, when an explosion killed 29 miners in West Virginia. It targets mines with spotty safety records.