The producer said in a US Securities and Exchange Commission filing that the order from the US Mine Safety and Health Administration was issued to Cumberland Coal Resources on April 8 for a condition at its Cumberland longwall mine near Waynesburg, Greene County.
Alpha officials said the order related to methane levels detected in the mine and a portion of the operation closed as a result.
No specific readings were disclosed.
MSHA modified the order on April 11, closing the entire mine with the issuance of a subsequent action.
The producer did not indicate if the mine was operating normally on Friday and company officials did not immediately respond to an ILN request for more details.
No injuries occurred in connection with the cited condition, Alpha said in the filing.
Alpha obtained Cumberland in its takeover of Foundation Coal in July 2009.