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The quantity of inflows which have been observed to date and are projected upon resumption of <br /> mining in future permit terms are considered to be insignificant with respect to effects on flow in <br /> the ephemeral surface drainages, or with respect to recharge of the coal seam. Based on <br /> information provided in the permit application, ground water intercepted by the mine does not <br /> appear to be in communication with any aquifers being put to beneficial use, and there are no <br /> registered wells within two miles of the permit boundary. <br /> The quality of water discharged from the mine is similar or higher quality than water in East Salt <br /> Creek at the confluence with McClane Creek, and any discharge is required to meet NPDES <br /> discharge standards. For these reasons, no detrimental impact to ground.water resources or to <br /> surface water quality downstream of the permit area is expected. Original ground water flow <br /> patterns in the mined area will ultimately be reestablished after the mine is sealed and the <br /> abandoned workings slowly fill with water. <br /> An alluvial aquifer has been identified along East Salt Creek. Monitoring wells established in the <br /> alluvium indicate that alluvial water levels fluctuate seasonally in response to flow in East Salt <br /> Creek. Data collected by the applicant from the Salt Creek alluvial aquifer indicate a carbonate- <br /> sulfate type water, similar to the characteristics of the surface water in the system as would be <br /> expected. No effects to alluvial ground water quality or quantity are anticipated. <br /> Surface Water Effects <br /> McClane Canyon is an ephemeral drainage which is normally dry. Flows that do occur are in <br /> response to snowmelt or intense rainstorms, and are usually of short duration. McClane Canyon <br /> drainage is tributary to East Salt Creek, which is an intermittent tributary of the Colorado River. <br /> Water quality is typical of and climate, ephemeral and intermittent systems located in marine <br /> deposited sedimentary land forms. Dissolved constituents often reach very high levels following <br /> dry periods and during the winter, when stream flows are made up almost entirely of recharge <br /> from ground water and from stagnant or semi-stagnant pools. Suspended solids levels are high <br /> during spring runoff and following high intensity rainstorms, due to sparse vegetation and erodible <br /> soils. <br /> Due to the limited areal extent of surface disturbance, existence of effective sediment control <br /> measures, and small quantity and acceptable quality of projected minewater discharge, operations <br /> at McClane Canyon have had little effect on the quality of water in McClane Canyon drainage or <br /> East Salt Creek, and no significant effects are expected. A full suite analysis of mine discharge <br /> water presented in Table 6 of the 2002 AHR shows a total dissolved solids (TDS) value of 1810 <br /> mg/l, compared to TDS values of 3000 to 4000 mg/l documented for East Salt Creek, at <br /> monitoring sites SW-1 and SW-8,in Table 4 of the AHR Following the conclusion of mining,all <br /> culverts and diversions will be removed, and a network of ephemeral drainages in geomorphic <br /> balance with adjacent areas will be reconstructed on the disturbed area. Following successful <br /> vegetation establishment it is expected that surface water hydrologic characteristics of the <br /> reclaimed area will approximate pre-mining conditions. <br /> III. TOPSOIL <br /> Soils resource information, including soil series descriptions, and evaluation of mine bench <br /> materials for use as plant growth medium is provided in Section 4.4 of the permit application. <br /> Information on topsoil management is provided in Sections 2.3 and 3.2,and information on topsoil <br /> 18 <br />