No injuries were sustained in the roof fall, which occurred on the mine’s main line belt on June 12.

Patriot officials believe the suspension of production at Harris will be in effect until the end of June.

“The lower production is expected to negatively impact second quarter 2010 earnings,” Patriot added, but did not indicate how much.

Patriot produced about 630,000 tons of coal in 2009. Analysts told news wire service Reuters Tuesday that Patriot could lose 50,000t of production just as it was planning to ramp up for steelmaking demand.

Harris was reopened last month after ventilation issues forced its closure by the US Mine Safety and Health Administration.

An agency spokesperson told ILN in May that federal inspectors discovered air flowing the wrong way in the mine’s bleeder and ordered the entire mine to evacuate with operations suspended.

West Virginia Office of Miners’ Health, Safety and Training spokesperson Leslie Fitzwater also told ILN that Harris No. 1 had received a violation notice just over a week prior, for low oxygen levels in parts of the mine.

When federal officials returned to the mine and discovered the issue had not been rectified, the closure order was initiated.

Patriot Coal officials did not immediately respond to an ILN request for more details.

Harris No. 1 is part of the Rocklick complex in southern West Virginia. All of Harris’s coal is sold on the met market and extracted from the Eagle seam.

The operation produced about 115,000t of coal in the first quarter of this year. Despite historically being a 4 million tons per annum operation, the mine reported 630,000t in 2009.

The mine is one of 14 active mining complexes in Patriot Coal’s portfolio. It controls 1.8 billion tons of proven and probably coal reserves and focuses its interests in Appalachia and the Illinois Basin.