2010-07-27_PERMIT FILE - M2009076 (16)

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• All trash and loose debris shall be collected and disposed of in an appropriate manner. The Reclamation Cost Schedule, included as an appendix to this Exhibit D, provides for costs to dispose of this material in a municipal landfill. No empty containers or buckets shall be left outside to prevent collection of stagnant rainwater. There is no need for any final grading or re-vegetation. This site is fairly flat and contains parked and stored equipment. These reclamation measures are entirely appropriate to restore this property to its current Mining District zoning designation, resembling rangeland. Clear Creek county currently has the patented mining claims of this property zoned M-I (inning and/or residential). The segments of property that have been added to these parcels via the BLM land purchase program are zoned M-2 (mining only). A copy of Clear Creek county zoning regulations are attached at the end of this Exhibit D. It shall be stressed that the only permitted use of M-2 zoned property in Clear Creek county is MINING. Tailings Impoundment Process Water: During normalized operations, process water contained in the Tailings Impoundment is continually recycled to the Water Holding Pond as an important processing medium. Reclamation measures shall be prescribed to manage this process water in the event of unforeseen cessation and forfeiture of the reclamation bond. As previously described above in the Mobile Millsite Reclamation section, any remaining process water in the various mill process circuits and the Water Holding Pond may be drained down to the Tailings Impoundment via the double walled HDPE pipeline for disposal. The amount of water anticipated from the Mobile Millsite facilities is approximately 20,100 gallons. This water can be drained down gradually and in a very controlled manner inorder to prevent overwhelming the Tailings Impoundment facilities. The total process water that may have to be contended with is 20,100 gallons from the Mobile Millsite + 201,1.00 • gallons that may be stored in the Tailings Impoundment Pond (refer to Exhibit T. 6.4.20(7)(f)) = 221,200 gallons or 0.68 acre-ft. Since this process water is not in a condition that can be discharged to the environment, a treatment method must be used. Evaporation is the best solution. Considering the relatively high pan evaporation rate averaging 38 inches/year and the average precipitation of 15.72 inches/year, the net evaporation rate would be 22.28 inches/year. At this net rate, it could be reasonably expected that it could take 4-6 months to passi%,ety evaporate this water over an average pond area of 1 acre. To accelerate evaporation, a system of pumps and forced evaporation equipment may be employed. Western Pump & Dredge in Grand Junction, CO offers rental units. One such unit is capable of processing 45 gal./min. at our climatic conditions. At this rate, this equipment could accelerate the forced evaporation period of time within 1 week. Measures shall also be applied to any residual stormwater that may have been captured by the Stornnwater Sedimentation Collection Pond. A maxinunum storage volume of 184,430 gal. should be considered. Since this water is diverted stonmyater, it should be in a quality acceptable to be discharged down Hukill Gulch in the normal course of the watershed. This should be done within 72 hours of the stonn event. Enough time should be allowed for any sediment to settle before pumping operations. At an easily achievable 65 gal/min, it would take 2 days to pump this water. If contamination is evident, than this water shall be evaporated in the same manner as the process water. After any standing water has been evaporated, leachate collection will begin to diminish rapidly. The hydraulic conductivity and saturation characteristics of the tailings has been analyzed by TRI/Environmentah and is reported in Exhibit C. After surface water evaporation, it can be assumed that the slimes fraction of the tailings are impounded in a saturated state starting at about 20% moisture content. Consolidation and conductivity of the entrained moisture will progress until a slimes fraction consolidated density of 109-1.11 lbs/ft3 is reached with a corresponding optimum • moisture content of 14%-16%. At this stage, evapotranspiration will sufficiently provide for a natural return to a hydrologic balance in this semi-arid clime. A conservative analysis can be approached assuming that the pan evaporation rate (averaging 38 inches annually) is less than the effects of evapotranspiration. Evapotranspiration Page 6 of 9