"Lower shipment levels, partially driven by poor eastern rail service, contributed to the guidance revision for 2010," Arch chairman and chief executive officer Steven Leer said late Tuesday.

"In addition, the Mountain Laurel operation was impacted in December by geologic challenges, which marginally affected our planned production during the quarter."

The company said the geologic issues at Mountain Laurel will force the mine’s longwall to idle for most of 2011’s first quarter as development work is done to prepare the next panel. Officials estimate longwall production will recommence in mid to late April.

West Virginia mine’s customers will receive coal from the five continuous miner sections as well as inventory coal during the stoppage.

While the idle will impact its first-quarter numbers the company expects it will make up part of the delayed production over the course of the year.

“Despite the temporary longwall outage, Arch expects to achieve record-setting coking and pulverized coal injection shipments of at least 7 million tons from its central Appalachian operations during 2011,” it said, adding that it had committed about 3Mt of met coal for 2011 delivery.

As it finalizes its fourth-quarter figures for an earnings conference late this month, the St Louis-based operation said it expected 2010 operating earnings per share to be $US1.11-$1.15, versus a previous guidance of $1.25-$1.40 outlined in late October.

Earnings per share for the year are anticipated to be 94c-98c, down from its prior expectation of $1.09-$1.23 and takes into account early debt extinguishment costs and supply agreement amortization.

Adjusted earnings before interest, taxes, depreciation, depletion and amortization guidance have been lowered to $718-$726 million, compared to the previous guidance of $750-$790 million.