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SITE COND=ONS <br /> General <br /> The Mine 3, 4 and 5 pad areas are formed on excavated rock surfaces which are <br /> inclined toward the highwall at 2 to 10 per cent slopes parallel to the plane of <br /> the westerly dipping coal seam. The pad area surfaces are composed of loose, <br /> fractured sandstone and shale bedrock of the Mancos Formation, coal spoil and <br /> excavated bedrock waste piles. Each pad area has been notched into very steep <br /> mountainous terrain with average natural undisturbed slopes that range from 70 <br /> to 100 per cent and occasionally in excess of 45 degrees. Disturbance of even <br /> small areas of 0.1 acres involve large exposures of barren slopes that are <br /> difficult to vegetate over extended time periods. Many slope areas are stable <br /> with a miniman apparent factor of safety. <br /> Mine Number 3 NOTE: New Pond added (1984) at lower coal bin (pp.48.1) <br /> Mine No. 3 pad area includes 4.86 acres of excavated surface (Plate 3-1) . <br /> The surface shape of the excavated area is irregular with grades that very from <br /> 5 to 7 per cent, generally west toward the bighwall. <br /> The steep inclined rock highwall extends 50 to 100 feet above the mine portal <br /> (70 to 80 degree slope) . Above the highwall is an abandoned exploration road that <br /> traverses the entire length of highwall. <br /> Existing sediment and drainage control structures include three sedimentation <br /> ponds (Plate 3-2) . Pond 3-1 is at the north end of the pad are. The top of the <br /> existing 14 ft. high dam that forms Pond 3-1 is within 80 feet of the edge crest <br /> of steep slope. Overflows from the pond such as 0.5 cfs of mine discharge, have <br /> formed a confined narrow charnel into exposed bedrock slope. This pond is adjacent <br /> to an avalanche path that is frequently active. <br /> Ponds 3-2A and 3-2B occupy the south end of the pad area. Pond 3-2B, the lower <br /> pond, abuts the haul road within 40 feet of a steer dropoff slope. <br /> Mine Number 4 <br /> The Mine No. 4 pad area includes 2.86 acres of excavated surface (Plate 4-1) . <br /> The surface shape of this excavated area is irregular with grades that vary from <br /> 1 to 3 per cent in a general west direction toward the highwall. The mine portal <br /> pad is on the nose of a ridge. Access is via Road 'C' . This mine is in the upper <br /> Dutch Creek Drainage area. Road 'C' traverses very steep terrain (707. + grades) <br /> that has been subjected to slope failures, as shown in Plate 4-1, and debris slides. <br /> Existing sediment and drainage control structures include one sedimentation <br /> pond (4-1) west of the main building. (Plates 4-1 and 4-2) A runoff collection <br /> ditch and berm confine and direct overland flows to Pond.4-1. <br /> -2- <br /> 44 <br />