By Nate Raymond WASHINGTON (Reuters) – The U.S. Supreme Court on Monday turned away former Massey Energy Co CEO Donald Blankenship’s bid to overturn his conviction on a charge of criminal conspiracy stemming from a 2010 West Virginia mine explosion that killed 29 coal miners. The justices declined to hear an appeal by Blankenship, who served a one-year sentence after being found guilty in 2015 of a single misdemeanor charge, of a lower court’s rejection of his arguments that the conviction should be tossed due to prosecutorial misconduct. Blankenship, 72, had faulted federal prosecutors for fa…