2020-08-07_GENERAL DOCUMENTS - C1981010

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B presents the 2010 -2019 water quality data for springs and seeps at Trapper Mine. Flow from the springs and seeps is shown on Table B-2. The table indicates that only the East Pyeatt discharged during 2019 at a rate exceeding 5 gallons per minute, the minimum for collecting a sample. The NPDES permit#CO-0032115 issued by the Colorado Department of Public Health and Environment describes water quality monitoring requirements. Pit dewatering occurs in L,N Pits, and well dewatering in the G Pit wells. All pit water is routed to NPDES drainage systems with discharges monitored at the approved outfall. Dust suppression for the main haul road consumes all the water yielded from dewatering activities. Currently a number of the listed outfalls encompass Phase III bond released areas and therefore are no longer subject to DRMS monitoring requirements. IV. Topsoil Soil information can be found in Section 2.6, Volume II and Section 4.9, Vol. IV. The Division previously granted a variance from topsoil removal in accordance with Rule 4.06.2(2)(a). Specific areas which the operator will not strip topsoil are limited to rocky areas which occur over limited areas throughout the mine area. Each area approved is handled separately as a minor revision to the permit and no general variance is currently approved. V. Sealing of Drilled Holes and Underground Openings Sealing of wells, holes, and other openings is discussed in permit Section 3.3, Vol. III. The Division requires each hole, well, or other underground opening be capped, sealed, backfilledor otherwise managed as per Rule 4.07.3. VI. Use of Explosives The blasting plan, as well as other items related to blasting, are discussed in permit Section 3.4, Vol. III. The Division approved blasting at times other than those described in the blasting schedule due to unavoidable hazardous situations. These situations include elimination of misfires, adverse weather, equipment failure, and safety related reasons (4.08.3(2)(b)(v) and (4.08.4(2)). VII. Disposal of Excess Spoil Permit section 3.5.3, Vol. III of the application discusses disposal of excess spoil. In accordance with TR106 and Appendix T, the K-Pit Buttress Fill is no longer required. The Horse Gulch Fill is described in Appendix T and inspected in accordance with 4.09.1(11), and meets the definitions and regulations associated with valley fill and head of hollow construction. The Horse Gulch underdrain and runoff diversions were constructed in accordance with Rules 4.09.2(2),4.09.3(1), and 4.09.2(7). The slope stability analysis for the Horse Gulch Fill demonstrates that the fill is designed to meet rules (4.09.1(7)) and 19