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