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<br />• <br />• <br />IV, EXHIBIT D -MINING PLAN <br />4.01. RATIONALE FOR AMENDED MINING PLAN <br />In general, mining activities at the Morrison Quarry will not fundamentally change as a result of <br />Amendment No. 4. The substantial change proposed by this amendment is an increased mining azea in <br />the North Quarry. This increase is the result of recent annexation of the quarry into the Town of <br />Morrison from unincorporated Jefferson County. The expansion will allow for construction of a raw <br />water storage reservoir in the North Quarry azea. As part of the plan for such a facility, Cooley has also <br />committed to remining the old highwalls at the west end of the existing North Quarry to improve visual <br />impacts of historic mining activities. <br />Cooley was annexed into Morrison to create apublic-private partnership that will create the opportunity <br />for Morrison and Cooley to store raw water rights in bedrock reservoirs at the site. The Town requested <br />options on two permanent reservoir sites: Permanent Reservoir No. 1 in the Central Quazry and <br />Permanent Reservoir No. 2 in the North Quarry. Reservoir No. 1 will have a minimum capacity of 500 <br />acre ft (ac-ft) and will be conveyed to the Town in the year 2000 pending final commitment to <br />construction of the reservoir by the Town in 1998. Reservoir No. 2 will have a minimum capacity of <br />1000 ac-ft and will not be available for approximately 30 years. Final design and construction of thz <br />reservoirs and appurtenant raw water system facilities will be undertaken jointly by Cooley and the Town. <br />The change in ultimate land use resulted in changes to mined areas, mine phasing and reclamation <br />planning. These changes are the rationale for this amendment to the mining and reclamation plan for the <br />Morrison Quazry. <br />4-02. GENERAL APPROACH TO MINING <br />Mining and reclamation will proceed in three major phases, with several subphases, which will be <br />employed to: 1) develop the quarry in a manner that will disturb only limited areas at a time; 2) facilitate <br />reclamation of mined slopes in inactive areas in a timely manner; and 3) accommodate mine operations <br />considerations. The configurations shown for all phases and subphases aze the most aggressive <br />configurations which are likely to be praaical from a geotechnical perspective. Less aggressive <br />configurations (i.e., ones with shallower mine slopes) are possible. Operational considerations, rock <br />quality, slope stability, and visual impacts will all influence the actual buildout for any phase or subphasz <br />which may be less extensive than the geometries shown. However, in no case will the limits of mining <br />be outside the limits shown. Brief summaries of activities during each phase are as follows: <br />Phase I <br />Phase I develops the Central Quarry to its final buildout configuration down to approximately EI <br />6360 ft in preparation for Reservoir No. 1, repairs the failing east highwall in the present Central <br />Quarry, and opens the North Quarry immediately north of the existing process facilities resulting <br />in a platform at approximately EI 6455 ft. No subphases aze included in Phase I. The Central <br />Quarry and the North Quarry will be developed simultaneously during Phase I resulting in the <br />end highwall and bench configuration shown. The focus of mining during the initial several <br />• •~~ IV-1 <br />/"l~~ <br />