UPDATE 1-Consol Energy sees layoff at Pennsylvania mine

(Adds mining timeline)

SAN FRANCISCO, Sept 5 (Reuters) - Coal miner Consol Energy Inc (CNX.N) said on Wednesday that up to 111 workers at its Mine 84 in Pennsylvania may be laid off during a two-week period beginning Nov. 7 because the mine is not meeting its target for return on capital.

The mine, near Washington, Pennsylvania, has a total work force of 482 employees.

Consol said it plans to suspend longwall development at the mine in November and to produce only coal already developed for its longwall system.

Development of blocks of coal to be mined by the longwall system is done with smaller mining machines.

Pittsburgh-based Consol said mining will continue until coal developed for longwall mining is depleted, which could occur in the second quarter of 2008.

At that time the mine, which produced 3.5 million tons of coal for electric power generation in 2006, will be idled, the company said. (Reporting by Leonard Anderson)