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The facilities are basic,and their number is small;all of them will be utilized during normal operations. <br /> Monitoring them,therefore,will primarily be by visual inspection when the site is active and when <br /> starting up or shutting down for a period. Drainage onto,within, and off of the site will be inspected and <br /> maintained according to the mining plan in Exhibit C. <br /> All of the potential runoff from the area of disturbance will be contained and directed to existing <br /> discharge sedimentation pond outfall 001 from CDPS Permit No. CO0038334 (permitted to 4.4MGD). <br /> Response to a release of any material and the clean up procedure will be to employ the proper <br /> earthmoving equipment to pick it up and place it within the containment provided by one of the <br /> appropriate facilities(e.g.,stockpile area,operations pad, building,etc.) <br /> The facilities'capacities and their designed containment will be appropriately constructed for the types <br /> of material and the planned volumes. Please see further discussion under Exhibit C. <br /> (8) <br /> Groundwater around this area has been studied extensively,due to known metals loading and recent <br /> clean up activities. The site lies within the South Mosquito Creek drainage,five miles west of and 1,000 <br /> feet above the Town of Alma,and two miles east of and 2,000 feet below the upper limit of the <br /> watershed (top of Mosquito Range). Historic mining in parts of the watershed began with prospectors <br /> noting natural metal mineralization in the local geology. Mineralization has caused higher than normal <br /> background levels in the water quality. The mine openings and waste dumps of the numerous historic <br /> mines within the drainage have historically contributed significantly to overall degradation of surface <br /> flows in South Mosquito Creek,especially zinc levels.Zinc concentrations leaving the Site and entering <br /> South Mosquito Creek have been reduced by more than 90%since 2016 through permanent re-routing <br /> of non-tributary groundwater from the upper mine areas, and collection of this water through the <br /> Leadville Limestone/Dolomite formations. <br /> (c) <br /> The underlying geologic formations in the general area of the permit include(from west to east) Early <br /> Tertiary intrusive and Tertiary intrusive rocks, pre-Cambrian schist and gneiss,and Pennsylvanian <br /> sedimentary rock. Groundwater discharge is only through the permitted discharge point from the mine <br /> tunnel. <br /> The groundwater at the London Mine was decreed non-tributary in 1986 under Water Decree W-83-14- <br /> 76 to a maximum flow of 7.4 CFS. MineWater LLC under Consent Order IC-160803 has been methodically <br /> dewatering the Leadville Dolomite formation to reduce intrusion of groundwater to the historic workings <br /> of the London Mine. <br /> MineWater has identified that the American Shaft is a source of a small amount of flow(about 4GPM) <br /> causing contamination in the mine workings to migrate toward the Water Tunnel.The mining proposal <br /> intends to pull back waste from next to the Shaft and to eliminate run-on to the collapses adjacent to the <br /> Shaft,thereby further reducing surface flow to the underground mine workings and reducing zinc <br /> contamination moving from the upper mine workings to the London Mine Water Tunnel. <br />