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No attempt has been made to show the effects of the propagation of shock waves from the surface blasting, or their possible effects on pillar loading. In a phone conversation with Richard Dick of the United States Bureau of Mines Twin Cities Blasting Vibration Research Center, concerning pillar loading, he stated that for peak partical velocities of less than 2.0 in/sec, loading would have no effect on pillar strength. Peak partical velocities between 2.0 in/sec and 4.0 in/sec would have negligible effect on pillar strength and only those velocities above 4.0 in/sec should have any effect on pillar strength. Although blasting will not effect pillar strength, roof and rib falls may result from the vibrations. The East Main Extension and the 4th East Panel are flooded areas where water is caught and then pumped up-mine to the longwall area. The 1st Left Panel has the pillars removed and is caved. The only panel currently accessible is the 2nd Left Panel. Safety concerns, for the underground workers that may be in the area of the 2nd Left Panel, due to roof or rib falls will be alleviated by blasting only during Empire Energy's shift change, when no workers will be in the area. To ensure that all underground workers will be notified, Trapper Mining Inc. will use a controlled blasting schedule which will be coordinated with Empire Energy Corporation and shall result in notification of a blast 24 hours prior to detonation. No long term roof or rib degradation are anticipated as possibly as few as 30 blasts will affect the 500 horizontal foot barrier areas. As the 2nd Left Panel is currently the only accessible area within the 500-foot boundary, it will require more roof and rib testing upon entry, but no more than standard safety practice allowed for previously. By allowing Trapper to blast and subsequently surface mine this area, an improved resource recovery may be obtained from State Coal Lease 463-13, Federal Coal Lease C-25948, and County Coal Lease 117764. The area that lies within 500 feet, horizontally, of the underground workings encompasses approx- imately 75 acres. An estimated 930,000 tons of surface coal are recoverable. This tonnage may be lost if not removed prior to Empire's longwall mining underneath the surface mineable coal seams. No surface water should enter the underground workings from the surface dis- turbance and blasting. The 800-foot vertical separation between the workings will prevent this. Additionally, no effect is foreseen on the Twenty Mile Sandstone Aquifer as it lies more than 200 feet below the lowest mineable sur- face coal. The strata separating the R coal seam slowest coal seam to be