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been affected by the mining operation at a compliance point at that <br />location. <br />6. Leachate impacts on alluvial water -TDS concentrations in the two <br />alluvial monitoring wells downstream from the Edna Mine (TR-3 and <br />TR-4) have remained around baseline levels, thus indicating little or no <br />adverse impact from spoil leachate (annual hydrology reports). <br />7. L.eachate impacts on surface water -Monitoring data through <br />2001indicate spoil leachate has increased the TDS levels in Trout <br />Creek immediately downstream from the mine, reaching a maximum <br />of about 1400 mg/1 in one sample in 1995. Since then, the annual <br />maximum has declined to less than the predicted maximum of 1,186 <br />mg/l. The increased TDS in Trout Creek caused by the leachate has <br />not caused an exceedance of [he instream standazds. The Colorado <br />Water Quality Control Division (CWQCD) has not found the mine's <br />discharges to Trout Creek to be in violation of the discharge permit <br />limitations. There were several exceedances of the discharge permit's <br />sulfate limitations in 1999 through 2001. CWQCD has enforcement <br />authority for the discharge permit and noted some of those <br />exceedances in the discharge permit when the permit was issued in <br />2000. <br />8. Pre-law leachate vs. post-law leachate - Pre-SMCRA spoil springs <br />have hindered recognition of the hydrologic impacts resulting from <br />mining completed since the enactment of SMCRA (page 2.SB-4 of <br />Appendix 2.SB). <br />9. Duration of elevated dissolved solids in leachate -Continuing elevated <br />levels of TDS in leachate, now several years since mining ceased, is <br />consistent with elevated solids remaining elevated for a few hundred <br />years (annual hydrology reports). <br />III. Topsoil <br />A. The Division previously granted a vaziance from topsoil removal in <br />accordance with Rule 4.06.2(2)(a) for steep slope azeas of the eastern <br />portion of the Moffat Area. Topsoil was redistributed on those azeas. <br />Some portions of the West Ridge Area were mined prior to August 3, <br />1977, and no topsoil was salvaged. Available spoil materials were seeded. <br />Steep slope variances were also granted for portions of the West Ridge <br />Atea. Details on these variances can be found in Section 4.3.1 and in <br />Exhibits 4.3-1 and 2-3.1 of the permit application. <br />Edna Mine 23 Permit Renewal No. 4 <br />