Alpha Natural Resources confirmed geological issues in the Waynesburg, Greene County, operation’s headgate area and idled the mine on July 15, impacting 450 workers.
Alpha said the remaining skeleton team had mitigated the conditions to allow operations to resume and the force majeure be lifted.
"We maintained a reduced workforce of employees who did an outstanding job of focusing on safety first to return the Cumberland Mine to operation,” Alpha president Paul Vining said.
"Safety will always take top priority for Alpha, and it was absolutely critical that we mitigate the adverse conditions before resuming mining operations.”
Vining said that while mining and coal shipments had resumed, mine personnel were gradually ramping up operations while continuing to monitor the headgate area geological status, and all mine safety and operations conditions.
It is unclear if and when the full staff of 450 will return to work at the mine.
Alpha previously warned the temporary idling would impact Alpha's eastern steam coal shipment volumes as well as its cost of coal sales per ton for the region in the third quarter.
“Obviously, this event will impact our Pitt 8 sales and our Eastern cost of coal sales per ton in the third quarter,” Crutchfield said.
As a result of the issues, Alpha said its whole-year adjusted cost to coal sales for the eastern region would be in the range of $72 to $76 per ton. It is expected the company will update the figures now that the operation has restarted.
Costs at Cumberland and its sister mine, Emerald, were about $52/t for the 2.2 million tons it produced in the second quarter.
According to the company’s data, the Cumberland operation shipped 6.4Mt last year and Emerald shipped 4.2Mt.
The idle is the second in just three months for the thermal coal operation.
On April 8, the US Mine Safety and Health Administration issued a federal imminent danger order for elevated methane levels and ordered a stop to operations.
The mine, which extracts from the prolific Pittsburgh 8 coal seam, reopened about two weeks later.
