1996-01-11_REPORT - C1981041 (2)

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Mining Summary During the year mining was done at both the Roadside North Portal (RSN) and the Roadside South Portals (RSS). In the RSS, mining continued on a limited basis in the 11 and 12 West panels. These panels were developed westward from the No. 3 South Mains in 1993 and 1994 and secondary mining was done in 1994 and 1995. The 11 West was completed in February and a small amount of mining was done in 12 West during March and April. The remainder of 12 West is being abandoned due to roof falls in the No. 3 South Mains. During this time an emphasis was being placed on implementing a new mining system at the RSN, continuous haulage. Due to low productivity associated with geologic problems, rock spars, the continuous haulage system was moved to the RSS in July. Secondary mining in the form of mining rooms continued for the remainder of the year at the RSN in 1 West panel. In the RSS, the continuous haulage unit was used to develop No. 4 South Mains parallel to No. 2 South Mains then the 6 East panel was started in December. Pillar sizes differ throughout the mine. The mains and submains which are used to transport men into the mine and coal out of the mine were typically driven on 100 x 100' centers leaving a 81 x 81' pillars. The No. 3 North Mains in the RS N was driven on 70 ft. x 100 ft. centers. The large pillars in the mains and submains are needed to handle the stress of the overlying strata for the life of the mine. As a result of the large pillars, the extraction ratio is approximately 34% for the 100 x 100' development and 41% for the 70 x100' development. The pillars in the panels are usually smaller in an effort to increase extraction and decrease cost. The pillar spacing for mining with the continuous haulage unit was generally 70 x 70' with crosscuts angled at 60°. Crosscuts in the No. 4 South Mains-RSS also included 75 and 90° angles. The extraction ratio for these pillars is approximately 49%. Secondary mining during the year involved developing rooms on 60 x 60' centers in 11 West-RSS and 70 x70' centers in 1 West-RSN. Extraction ratios for these pillars was approximately 53 and 47% respectively. Only a few pillars in 12 West-RSS were pillared for an extraction ratio of approximately 75%. Projected Mining During the 1996 mining is projected to continue in both the RSS and the RSN. In the RSN, the No. 3 North mains will be developed north to the permit boundary and a panel started west near the north permit boundary. Mining will be done using a continuous miner and shuttle cars. In the RSS, the 6 West panel will be developed east to the permit boundary and then subsequent panel to the south will be mined with the continuous haulage with no secondary mining. Surface Inspection Two regular inspections were made during 1994. These inspections consisted of walking and driving tours of the surface above the projected, present and recently abandoned mining areas, taking photographs of the immediate area and marking the routes traversed on a map. Were subsidence Page 2