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area (adjacent to the East Cresson Mine area backfill), and will accept overburden from <br />the WHEX portion of the East Cresson Mine area and the Main Cresson Mine area. <br />Under MLE2, the redesigned ECOSA footprint will be extended to approximately 274 <br />acres, and will hold approximately 120 MT of overburden. The original design has been <br />changed to allow more efficient use of the available area for overburden storage and <br />recognize the additional geochemical and hydrogeologic information that has been <br />collected. The ECOSA will be located within the Grassy Valley surface drainage area <br />and any surface runoff from the ECOSA will flow into Grassy Valley. Ground water <br />infiltration into the ECOSA will flow directly to, or be diverted by subsurface rock - filled <br />drains, into the diatreme. <br />Construction <br />The total capacity of the redesigned ECOSA will be approximately 120 MT at the design <br />configuration. The ECOSA will be expanded to the east to the Grassy Valley surface <br />drainage area. The maximum elevation of the ECOSA will be approximately 10,565 feet <br />amsl once completed. Initial site preparation will include vegetation salvage, growth <br />medium salvage and stockpiling for use in surface reclamation, followed by removal of <br />clay materials from select areas in the footprint for use in the VLF liner systems. <br />Following clay removal, additional surface preparation will include furrowing the base of <br />the ECOSA to enhance infiltration drainage into the underlying diatreme rock, and to <br />transfer infiltrating ground water to locations where it will infiltrate to the volcanic <br />diatreme. Sediment and drainage control measures will be installed downgradient of the <br />ECOSA as appropriate prior to surface disturbance. <br />For the expanded footprint of the redesigned ECOSA, a road will be constructed to <br />access the toe of the area. The facility will then be constructed by end - dumping, initially <br />with a 300 -foot dump height, finishing with 70 -foot lifts with the ultimate toe of each lift <br />set back 100 feet from the ultimate crest of the lift below, to facilitate final grading to a <br />2.5H:1V slope. <br />During construction and reclamation of the facility, and for a period that has been <br />calculated to be approximately 20 years thereafter, infiltration of precipitation to the <br />surface of the ECOSA will be retained within the overburden until the field capacity of <br />the placed overburden is reached. After that period, infiltrated water will flow out of the <br />facility into the underlying colluvium and bedrock at an expected rate of approximately <br />85 gpm. Based on the expected flow rate and the existing neutralizing capabilities of the <br />ECOSA rock, water exiting downward from the base of the ECOSA is expected to be of <br />Cripple Creek & Victor Gold Mining Company <br />Cresson Project Mine Life Extension 2 <br />5 -20 <br />