BECKLEY, W.Va. (AP) — A former superintendent at West Virginia's Upper Big Branch mine — where an explosion killed 29 — will learn his fate after pleading guilty to a federal conspiracy charge.

Gary May will be sentenced in federal court Thursday. He's cooperating with prosecutors in their ongoing criminal investigation of the 2010 explosion that killed 29 miners at the former Massey Energy operation.

May pleaded guilty last March. He was accused of defrauding the government through his actions at the mine, including disabling a methane gas monitor and falsifying records.

A plea hearing is set next month for former Massey executive David Hughart, who's accused of two federal conspiracy charges. Hughart's cooperation has been viewed as a sign that authorities may be gathering evidence to target officials further up the Massey hierarchy.