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RULE 2 - PERMITS <br />mining- related impacts were identified and evaluated and the effectiveness of operational protection <br />and control measures and reclamation activities in mitigating potential impacts were considered in <br />• the assessment of probable hydrologic impacts. Probable Hydrologic Consequences are <br />summarized below. Later sections assess the probable hydrologic consequences of the planned <br />PSCM in detail. <br />2.05.6 (3)(b)(iii) Probable Hydrologic Consequences <br />Rule 2.05.6(3)(b)(iii) requires determination of probable hydrologic consequences for the proposed <br />mining operations. This rule indicates that these consequences must be defined for both the permit <br />area and adjacent areas, for quantity and quality of surface and ground waters. Baseline conditions <br />must be established, and possible impacts from the proposed activities must be anticipated. <br />Surface and ground water hydrologic systems may potentially be impacted by mining and related <br />operations. These impacts are not expected to be significant, will not effect either surface or <br />groundwater users, and are expected to be localized and temporary in nature. Operational <br />mitigation measures and reclamation of disturbance areas will result in effective restoration of <br />surface and ground water conditions similar to those existing prior to initiation of the PSCM <br />project. <br />The anticipated probable hydrologic consequences of mining coal as proposed in this application <br />are: <br />• Spoil springs near Little Grassy Creek are not expected to be impacted by dewatering of the <br />mine. <br />• • Dewatering of the mine workings will be necessary; inflows to the mine during dewatering <br />will be less than 75 gpm. <br />• The potentiometric surface will experience drawdown in the vicinity of the mine workings. <br />Re- filling of the dewatered mine voids and adjacent bedrock and recovery of the <br />potentiometric surface to pre- mining levels is expected to take at least 15 years. <br />• The hydraulic conductivity within the mine workings after mining will be much higher than <br />in the adjacent unmined areas and may affect the groundwater flow pattern and velocity <br />• No significant change to groundwater quality is anticipated. <br />• No effect on beneficial -use wells in the area is expected. <br />• No other significant changes to surface water quantity are anticipated. Limited discharge of <br />mine water may increase flows. <br />• No significant negative changes to surface water quality are anticipated. Limited discharge <br />of mine water may improve water quality. <br />These consequences are discussed in detail in the following subsections. <br />Potential Impacts to Groundwater and Probable Hydrologic Consequences <br />Groundwater inflow to the mine workings will be from two sources: undisturbed bedrock units to <br />the adjacent to the mine workings, and the spoils aquifer at the reclaimed Seneca II Mine east of the <br />mine workings. Groundwater inflow rates to the PSCM from the adjacent bedrock (overburden and <br />• Wadge coal) were estimated using analytical methods based on a line -sink model described by R. <br />W. Stallman (in Ferris et al., 1962). Stallman's equations for the situation in which the head in the <br />PSCM Permit App. 2.05 -69 Revision 12/17/09 <br />