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-30- within sedimentation systems. This accounts for approximately 0.10 percent of the drainage area of East Salt Creek below the confluence of Munger Canyon. Obviously, the impact of the operations on surface water quantity in East Salt Creek will be negligible. The impact on water quantity will also be minimal since water retained by the structures will be discharged following settlement of suspended solids. As mentioned previously, no wells or springs have been identified in McClane or Munger Canyons. No ground water rights have been adjudicated within a three-mile radius of the mines. Drilling operations conducted within and adjacent to the McClane Canyon Mine permit area have indicated that the Cameo coal seam becomes increasingly saturated downdip (northeast) from its outcrop along the side slopes of the East Salt Creek Drainage Basin. This is depicted on Figure 4.2-3 of Volume II of the permit application. As can be seen on the figure, the saturated zone extends downdip towards the northeast along northwest-southeast trending line. The outcrop line of the coal, as well as the East Salt Creek drainage, run roughly north-south in the vicinity of the permit area. Recharge to the Cameo coal seam occurs in an area where the coal seam subcrops in the East Salt Creek alluvium approximately two miles north of the McClane Canyon Mine permit area. The subcrop of the coal seam along East Salt Creak was created as the stream channel gradually cut through the sedimentary strata to the point where the stream channel intersected the Cameo coal seam on its way southward to the Colorado River. Very little recharge of the coal seams and sandstones occur along outcrops due to the very low precipitation rate (8.8 inches annually) and due to the steep slopes which favor runoff over infiltration. The underground workings of the McClane Canyon P1ine extend roughly eastward into the Cameo Seam from a point where the coal seam outcrops in McClane Canyon. McClane Canyon is a small tributary canyon to the East Salt Creek drainage. The mine workings of the McClane Canyon Mine are situated within a geologic structure identified as a graben. This graben is bounded on both sides by faults, referred to as the east and west faults. Mining of the coal is not possible beyond the faults because of the displacement of the coal seams. At the time of the initial McClane Canyon Mine permanent regulatory permit approval during the first quarter of 1982, no water was discharged from the mine workings. However, subsequent to the extension of the east mains to the east fault and north mains down dip to the northeast in a parallel line with the east fault, mine inflows increased gradually and required periodic discharge in accordance with an approved NPDES discharge permit. Mine inflows peaked at a rate of approximately 5.4 gpm two months after mine progress was stopped. Since that time, seepage of water into the mine has decreased to a level of approximately 1.6 gpm during the first quarter of 1985. The source of this water is believed to primarily from the edge of the saturated portion of the Cameo seam and to a lesser extent from the east fault which is recharged by portions of the McClane Canyon drainage transected by the fault at the surface and/or shallow aquifers from the upper reaches of McClane Creek.