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-25- comprises five-hundredths of one percent of the total drainage area of East Salt Creek above the confluence with Munger Canyon (67,288 acres). Further dilution would, therefore, occur by the time the runoff from the disturbed area reaches the alluvial valley floor. A similar relationship occurs for the portion of the operation situated along the East Salt Creek drainage. The disturbed area (43.4 acres) accounts for approximately six-hundredths of one percent of the total drainage area of East Salt Creek below the confluence with Munger Canyon (72,373 acres). Of the 35 acres top be disturbed by the portion of the operation situated in Munger Canyon, approximately 8.4 acres is required to be controlled by sedimentation ponds. The rest of the disturbance will consist of the haul road. The amount of area essentially removed from the drainage of Munger Canyon due to containment within the operation's sedimentation system is approximately 8.4 acres. This accounts for less than two-tenths of a percent of drainage area of Munger Canyon and less than two-hundredths of a percent of the drainage area of East Salt Creek. Obviously, the reduction of such a small amount of the drainage area will result in an insignificant reduction of surface flow tributary to the alluvial valley floor. Additionally, all surface runoff retained by the structures will eventually be returned to the system. Runoff from the portion of the mining operation situated along East Salt Creek (87 acres) will also be contained in sedimentation ponds, with the exception of the haul road which connects the central facilities area with the coal processing waste pile. The amount of area essentially removed from the drainage of East Salt Creek due to containment within the sedimentation system is approximately 73.2 acres. This accounts for less than six-hundredths of one percent of the drainage area of East Salt Creek below the confluence with Munger Canyon. This will result in an insignificant reduction of surface flow to the alluvial valley floor. As with the sediment ponds situated in Munger Canyon, all surface runoff retained by the structures will eventually be returned to the system. No ground water was encountered within coal seams and their associated roof and floor strata during exploratory drilling in the mine plan area. The applicant, therefore, does not anticipate any significant mine inflow which would require discharging of mine water. Munger Canyon is an ephemeral stream. Therefore, it's flow is not sustained by ground water during low flow periods through springs and seeps. If the mine were to experience mine inflows, the ground water depleted from the hydrologic system would not be significant. Therefore, the depletion of ground water will not impact the quantity of water tributary to the alluvial valley floor. The Division has sufficient information to determine the absence of alluvial valley floors in Stove and Buniger Canyons. Sideslopes in the canyons are excessively steep (16 to 50%) and are deeply incised. The potential for extensive deposits of unconsolitdated alluvium is minimal. Further, because these drainages encompass less drainage area than that of Munger Canyon, it is likely that there is insufficient surface water runoff to sustain agricultural activities. The fact that both streams are ephemeral indicates a low potential for subirrigation by springs or seeps. Inspection of 7 1/2 minute topographic maps also indicates that there is no irrigation along any stream courses in these drainages.