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The quantity of inflows which have been observed to date and aze 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 rechazge of the coal seam. Based on <br />information provided in the permit application, ground water intercepted by the mine does not <br />appeaz to be in communication with any aquifers being put to beneficial use, and there aze 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 dischazge is required to meet NPDES <br />discharge standazds. For these reasons, no detrimental impact to ground, water resources or to <br />surface water quality downstream of the permit azea 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 cazbonate- <br />sulfate type water, similaz to the chazacteristics 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 Fffects <br />McClane Canyon is an ephemeral drainage which is normally dry. Flows that do occur aze in <br />response to snowmelt or intense rainstorms, and aze 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 arid 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 aze made up ahnost 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 azeal extent of surface disturbance, existence of effective sediment control <br />measures, and small quantity and acceptable quality of projected minewater dischazge, 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 AHIi shows a total dissolved solids (TDS) value of 1810 <br />mg/I, compared to TDS values of 3000 to 4000 mg/1 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 azeas will be reconstructed on the disturbed azea. 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 />