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Surface Water Effects McClane Canyon is an ephemeral drainage which is normally dry. Flows that do occur are in response to snowmelt or intense rainstorms, and are usually of short duration. McClane Canyon drainage is tributary to East Salt Creek, which is an intermittent tributary pf the Colorado River. Water quality is typical of arid climate, ephemeral and intermittent systems located in marine deposited sedimentary land forms. Dissolved constituents often reach very high levels following dry periods and during the winter, when stream flows are made up almost entirely of recharge from ground water and from stagnant or semi-stagnant pools. Suspended solids levels are high during spring runoff and following high intensity rainstorms, due to sparse vegetation and erodible soils. Due to the limited areal extent of surface disturbance, existence of effective sediment control measures, and small quantity and acceptable quality of projected minewater discharge, operations at McClane Canyon have had little effect on the quality of water in McClane Canyon drainage or East Salt Creek, and no significant effects are expected. Following the conclusion of mining, all culverts and diversions will be removed, and a network of ephemeral drainages in geomorphic balance with adjacent areas will be reconstructed on the disturbed area. Following successful vegetation establishment it is expected that surface water hydrologic characteristics of the reclaimed area will approximate pre-mining conditions. III. TOPSOIL. Soils resource information, including soil series descriptions, and evaluation of mine bench materials for use as plant growth medium is provided in Section 4.4 of the permit application. Information on topsoil management is provided in Sections 2.3 and 3.2, and information on topsoil replacement is provided in Section 3.3. No topsoil was stripped prior to mine bench and haul road construction, as this disturbance occurred prior to the enactment of the Surface Mining Control and Reclamatipn Act (SMCRA). Topsoil was salvaged from subsequently disturbed areas including the sediment pond, riprap stockpile, and office facility areas, and, with the exception of one small area addressed below, will be salvaged from approved disturbance areas where construction has not yet been initiated. Figure 2.2-2 (Surface Facilities Map), shows site specific mapping of soils at an Order 1 or II level of intensity. The mapping indicates that soils in the vicinity of the sediment pond and riprap stockpile were Rivra Gravelly Sandy Loam Variant, and Nihill Loam, and office facility soils were Glendive Sandy loam. Soils to be affected by the proposed McClane to Munger haul road are mapped as Glendive Sandy Loam, and a small area of Rivra Gravelly Sandy Loam. A small area to be affected by the proposed realignment of the access road segment at the junction with the state highway is mapped as Havre Loam, saline phase. 21