(Reuters) - Federal authorities on Wednesday charged the former superintendent of a West Virginia coal mine where 29 workers died in a 2010 explosion with felony conspiracy for impeding mine safety enforcement efforts before the blast.

Gary May, 43, of Bloomingrose, West Virginia, was charged with conspiring to impede the U.S. Mine Safety and Health Administration's enforcement efforts at the Upper Big Branch mine between February 2008 and April 5, 2010, the date of the explosion, U.S. Attorney for the Southern District of West Virginia R. Booth Goodwin II said in a statement.

The charges carry a maximum penalty of five years in prison, Goodwin's statement said.

At the time of the blast, the mine was owned by Massey Energy, which has since been acquired by Alpha Natural Resources. Alpha Natural agreed in December to pay $1.5 million to each of the families of the 29 miners who died as part of a $209 million settlement of civil and criminal charges against the company.

(Reporting By Dan Burns; Editing by Cynthia Johnston)