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Since all disturbed-area runoff as well as mineflow from the Eastside site is <br /> routed into a sediment pond, and since there have been no discharges from this <br /> pond, there have clearly been no impacts of the operation on surface water <br /> quality. The worst-case predictions of the original Eastside Probable <br /> Hydrologic Consequences section would involve maximum sediment pond discharge <br /> during the low flow of Harvey Gap drainage, and would result in an increase in <br /> Total Dissolved Solids from 775 mg/l to 1054 mg/l (calculations in original <br /> Findings Document) . This impact would not affect irrigation, since the flow <br /> in Harvey Gap drainage would be less than 1 cfs during the low-flow season <br /> (non-irrigation season, October through early April ) . Containment of the <br /> runoff from the 12 acres of disturbed area at Eastside will have negligible <br /> quantitative effect on the flows in Harvey Gap drainage. <br /> The Probable Hydrologic Consequences section of the original Findings Document <br /> also predicted negligible ground water impacts, and this assessment is still <br /> valid. Seepage of water into the workings has remained at less than 2 GPM and <br /> is not expected to increase substantially with further mine development. <br /> There have clearly been no detectable hydrologic impacts, based on study of <br /> Annual Hydrologic Reports submitted by Eastside Coal Company from 1984 through <br /> 1988. <br /> Cumulative Hvdrologic Impact Study - Rules 2.05.6(3) and 2.07.6(2)(c) <br /> A Cumulative Hydrologic Impact Study (CHIS) was completed for the Eastside <br /> Mine and considers the hydrologic impact of all anticipated mining and <br /> reclamation activities in the area of the proposed operation at the mine <br /> during the permit renewal term. This CHIS is available in company with the <br /> most current versions of other such studies under a separate cover in the <br /> Permit Application File area of the Division. <br /> Pursuant to Rule 2.07.6(2)(c) and in consideration of the absence of <br /> demonstrated significant hydrologic impacts by the anticipated mining and <br /> reclamation operations in the study area, either individually or cumulatively, <br /> the Division finds the proposed operation at the Eastside Mine to have been <br /> designed to prevent material damage to the hydrologic balance outside the <br /> proposed permit area. <br /> IX. Alluvial Valley Floors —Rules 2.06.8 and 4.24 <br /> The original Findings Document for the Eastside Mine determined that farming <br /> on alluvial valley floors would not be affected, that no material damage to <br /> quantity or quality of alluvial valley floor water supplies was expected, and <br /> that the essential hydrologic function of alluvial valley floors would be <br /> preserved. There are no changes to this section. <br /> The operation is in compliance with the requirements of this section. <br /> X. Climatological and Air Resources Information - Rules 2.04.8, <br /> and 4.17 <br /> No changes are required to this section of the Findings Document. The <br /> operation is in compliance with the requirements of this section. <br /> -8- <br />