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discharge, operations at McClave Canyon have had little effect on the quality of <br /> water in McClave Canyon drainage or East Salt Creek, and no significant effects are <br /> expected. A full suite analysis of mine discharge water presented in Table 6 of the <br /> 2020 AHR shows a total dissolved solids (TDS)Value of 0.0 mg/l due to no outflow <br /> from the mine. Surface monitoring locations SW-1 and SW-8 documented no flow <br /> for East Salt Creek, at monitoring sites SW-1 and SW-8, in Table 4 of the 2020 <br /> AHR. Following the conclusion of mining, all culverts and diversions will be <br /> removed, and a network of ephemeral drainages in geomorphic balance with <br /> adjacent areas will be reconstructed on the disturbed area. Following successful <br /> vegetation establishment, it is expected that surface water hydrologic characteristics <br /> of the reclaimed area will approximate pre-mining conditions. <br /> In association with RN-06 and TR-15,the operator prepared a mass balance <br /> evaluation to assess the effects of irrigation season mine water discharge on the <br /> salinity (conductivity) of East Salt Creek water downstream from the point where <br /> discharge water enters the stream. The evaluation included data from the 2001 <br /> through 2005 irrigation seasons. During four of the five years, conductivity levels <br /> were reduced due to dilution by lower conductivity mine discharge water. During <br /> one of the 5 years (2005)there was a slight, but insignificant(0.2%; 0.004 mmho) <br /> increase. Over the five year period,there was an over-all 10.9%reduction in <br /> irrigation season conductivity on East Salt Creek downstream of the mine, resulting <br /> from minewater discharge. These results confirm that mine discharge is not causing <br /> a deleterious increase in stream salinity levels. <br /> IV. Topsoil—Rule 4.06 <br /> Soils resource information, including soil series descriptions, and evaluation of mine <br /> bench materials for use as plant growth medium is provided in Section 4.4 of the permit <br /> application. Information on topsoil management is provided in Sections 2.3 and 3.2, and <br /> information on topsoil replacement is provided in Section 3.3 of the PAP. <br /> No topsoil was stripped prior to mine bench and haul road construction, as this <br /> disturbance occurred prior to the enactment of the Surface Mining Control and <br /> Reclamation Act(SMCRA). Topsoil was salvaged from subsequently disturbed areas <br /> including the sediment pond, riprap stockpile, and office facility areas, and,with the <br /> exception of one small area addressed below,will be salvaged from approved disturbance <br /> areas where construction has not yet been initiated. <br /> Figure 2.2-2 (Surface Facilities Map) of the PAP, shows site specific mapping of soils at <br /> an Order I or II level of intensity. The mapping indicates that soils in the vicinity of the <br /> sediment pond and riprap stockpile were Rivra Gravelly Sandy Loam Variant, and Nihill <br /> Loam, and office facility soils were Glendive Sandy Loam. Soils to be affected by the <br /> proposed McClane to Munger haul road are mapped as Glendive Sandy Loam, and a <br /> small area of Rivra Gravelly Sandy Loam. A small area affected by the Haul Road <br /> segment at the junction with the state highway is mapped as Havre Loam, saline phase. <br /> xxi <br />