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-6- Extensive past mining disturbances characterize the general area of the Dorchester No. 1 Mine. In 1860 the first coal mine was opened in the northern portion of the Canon City Coal Field. Production areas spread through the central area and into the southern portion of the coal field in the early 1900's. Over 177 abandoned mines with 600 acres of existing associated surface disturbances have been identified by the Mined Land Reclamation Division's Inactive Mine Program. The proposed Dorchester No. 1 permit area, located in the southern portion of the Canon City Coal Field, is shown on Figure 3 along with the extent of previous mining within the adjacent area. The collection of baseline environmental information which shows what the area was like prior to any mining is, therefore, impossible. The existing environment in the general area of the Dorchester No. 1 Mine is one of an arid, steppe highland basin. The Canon City Coal Basin lies in the transition zone between the foothills of the Wet Mountains and the eastern Colorado plains, it ranges in elevation from 5,500 to 8,000 feet. The climate is directly influenced by the topography, with heavier rainfall and cooler temperatures in the mountains and less rain and warmer temperatures in the basin. Erosion of the mountains has resulted in a pediment surface within the basin from 0 to 100 feet thick. The action of several ephemeral and some perennial streams has cut through the pediment surface, exposing the coal-bearing Vermejo Formation. This easily accessed coal has been extensively mined since the turn of the century leaving many unreclaimed spoils and waste piles. Existing vegetation and soils are also influenced by the topography and surficial geology. Vegetation is predominately a grassland/woodland community dominated by blue grams grass on the gently sloping mesas and ponderosa pine on the hillslopes. Two riparian woodland communities were also found along ephemeral drainages within the permit area. Topsoil available within the permit area is a sandy loam derived from the pediment gravels. The A horizon ranges from 6.5 to l6 inches in depth and the B horizon ranges from 7 inches to over 6 feet in depth. Prior to any mining in the area, wildlife habitat and grazing were the land uses. Description of the Operations and Reclamation Plan Dorchester Coal Company proposes to mine approximately 800,000 tons of coal per year from the Dorchester No. 1 Mine using a conventional room and pillar system. The proposed permit area is approximately 1,400 acres in size. The legal description of the total proposed permit area is as follows: SW1/4. and an irregular 6.9 acre parcel located in the SW1/4SE1/4, Section 19. T205, R69W, 6th P.M., NE1/4NW1/4, W1/2W1/2, and an irregular 6.7 acre parcel located in the NW1/4NE1/4, Section 30, T20S, R69W, 6th P.M., NW1/4, NE1/4, SEl/4. NW1/4SW1/4, NE1/45W1/4, SE1/4SW1/4 and an irregular 16 acre parcel located in the SW1/4SW1/4, Section 25, NE1/4, Nl/2SE1/4, and an irregular 71 acre parcel located in the E1/2W 1/2 and in the Nl/2SW1/4SE1/4 and in the N1/25E1/45E1/4, Section 26,