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compliance point in any stratigraphic unit at the permit boundary. <br />Monitoring data from well TCS, immediately downdip from the <br />permit boundary, indicates the Trout Creek Sandstone has not been <br />affected by the mining operation at that location. <br />6. Leachate impacts on alluvial water -TDS concentrations in the <br />two alluvial monitoring wells downstream from the Edna Mine <br />[Technical Revision (TR)-3 and TR-4) have risen from around 500 <br />to over 900 mg/1 since 1996. This may be an impact from spoil <br />leachate, but a number of other reasons might bear on the rise.14 <br />Leachate impacts on surface water -Monitoring data through 2006 <br />indicate spoil leachate has increased the TDS levels in Trout Creek <br />immediately downstream from the mine (sites TR-C and D). <br />Concentrations reached a maximum of about 1400 mg/1 in one <br />sample in 1995. Since then, the annual maximum has declined to <br />less than the predicted maximum of 1,186 mg/l, and continues to <br />show a decrease with time. The increased TDS in Trout Creek <br />caused by the leachate has not caused an exceedance of the <br />instream standazds. The Colorado Water Quality Control Division <br />(CWQCD) has not found the mine's discharges to Trout Creek to <br />be in violation of the dischazge permit limitations. There were <br />several exceedances of the dischazge permit's sulfate limitations in <br />1999 through 2001. CWQCD has enforcement authority for the <br />discharge permit and noted some of those exceedances in the <br />dischazge permit when the permit was issued in 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 (PAP, page <br />2.SB-4 of Appendix 2.SB). <br />9. Duration of elevated dissolved solids in leachate -Continuing <br />elevated concentrations of TDS in leachate, now several years <br />since mining ceased, is consistent with predictions that such <br />elevated concentrations aze predicted for a few hundred years <br />(annual hydrology reports). <br />III. Topsoil <br />A. The Division previously approved a variance 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. Some portions of the West Ridge Area were <br />mined prior to August 3, 1977, and no topsoil was salvaged. Spoil, and <br />what topsoil was available, were seeded. Steep slope vaziances were also <br />'" 2005 Annual Hydrological Report <br />C-1980-001 Permit Renewal 5 Findings Page 27 of 33 Pages <br />