In an interview with International Longwall News, Murray Energy vice-president of business development and external affairs Rob Murray said that workers were informed of the lay-offs, which are expected to be permanent, on May 9.

The Galatia complex is controlled by Murray Energy subsidiary American Coal.

According to the Associated Press the circumstances are "operational in nature from a mining engineering and geological standpoint", but Murray noted to ILN that the issues were beyond the producer's control.

“It is important to point out that 644 persons remain to be employed at American Coal's New Era, Galatia North and New Future mines," he added.

“Due to the sudden, dramatic and unexpected nature of the aforementioned events, American Coal is providing its employees with as much notice as possible under the circumstances."

He did not elaborate on the specifics of the mine's issues, and did not comment on plans for the mine's status as the circumstances are reviewed.

Earlier this month, the company's Ohio operations were in the spotlight as part of a dispute with the Ohio Environmental Protection Agency.

According to the Associated Press, Murray Energy's American Energy Century mine and Ohio Valley Coal's Powhatan No. 6 operation could both be shut down due to plans the company has for a new coal preparation refuse site that has been opposed by the federal agency due to wildlife issues.

With the current site nearing capacity, the jobs of about 1000 workers could be in limbo if a resolution cannot be found for a new site.

The state EPA's final order can be appealed by the operator, but if the decision on the certification stands the operator will be forced to close both mines permanently.