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inorganic or metals constituents for which there are numeric standards in Horse Gulch. <br /> Ground Water Impacts <br /> The 2021 Annual Hydrology Report(AHR), Section 2.5 of the permit presents the <br /> most current information regarding springs and seeps at TMI. Appendix B presents <br /> ground water quality data from 2012 through 2021. Flow from the springs and seeps is <br /> shown on Table B-2. A CD submitted with the AHR provides all historical data. <br /> The NPDES permit 4CO-0032115 issued by the Colorado Department of Public Health <br /> and Environment describes water quality monitoring requirements. Pit dewatering <br /> occurs in L, N Pits, and well dewatering in the G Pit wells. All pit water is routed to <br /> NPDES drainage systems with discharges monitored at the approved outfall. Dust <br /> suppression for the main haul road consumes most of the water yielded from <br /> dewatering activities. Currently a number of the listed outfalls encompass Phase III <br /> bond released areas and therefore are no longer subject to DRMS monitoring <br /> requirements. <br /> IV. Topsoil <br /> Soil information can be found in Section 2.6, Volume II and Section 4.9, Vol. IV. <br /> The Division previously granted a variance from topsoil removal in accordance with Rule 4. <br /> 06.2(2)(a). Specific areas which the operator will not strip topsoil are limited to rocky areas which <br /> occur over limited areas throughout the mine area. Each area approved is handled separately as a <br /> minor revision to the permit and no general variance is currently approved. <br /> V. Sealing of Drilled Holes and Underground Openings <br /> Sealing of wells, holes, and other openings is discussed in permit Section 3. 3, Vol. III. <br /> The Division requires each hole, well, or other underground opening be capped, sealed, backfilled or <br /> otherwise managed as per Rule 4.07.3. <br /> VI. Use of Explosives <br /> The blasting plan, as well as other items related to blasting, are discussed in permit Section 3.4, Vol. <br /> III. <br /> The Division approved blasting at times other than those described in the blasting schedule due to <br /> unavoidable hazardous situations. These situations include elimination of misfires, adverse weather, <br /> equipment failure, and safety related reasons (4. 08.3(2)(b)(v) and (4.08.4(2)). <br /> VII. Disposal of Excess Spoil <br /> Permit section 3. 5.3, Vol. III of the application discusses disposal of excess spoil. <br /> In accordance with TR106 and Appendix T, the K-Pit Buttress Fill is no longer required. The Horse <br /> Gulch Fill is described in Appendix T and inspected in accordance with Rule 4.09.1(11), and meets <br /> the definitions and regulations associated with valley fill and head of hollow construction. The <br /> Horse Gulch underdrain and runoff diversions were constructed in accordance with Rules 4.09.2(2), <br /> 4.09.3(1), and 4.09.2(7). The slope stability analysis for the Horse Gulch Fill demonstrates that the <br /> fill is designed to meet rules (4.09.1(7)) and (4.09.2(1)). <br /> 17 <br />