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<br />St" IV. EXHIBIT D -MINING PLAN <br />•?<.Ol. RATIONALE FOR AMENDED MINING PLAN <br />In general, mining activities at the Morrison Quarry wilt not fundamentally change as a result of Amendment <br />No. 5. The substantial change proposed by this amendment is an increased mining area in the South Quarry. <br />This increase will more fully develop the South Quarry within the existing property and mineral conservation <br />zone boundary. The plan still allows for construction of a permanent raw water storage reservoir in the North <br />Quarry azea. <br />As part of the revised plan for the facility, the old highwalls at the west end of the existing North Quarry will <br />be partially remined and a fill slope will be constructed to improve visual impacts of historic mining activities <br />uphill and west of the reservoir site. Previously (Amendment No. 4) more extensive remining was proposed <br />for this area that would have created relatively flat slopes that could have been backtilled top to bottom for <br />visual impact mitigation. CAMAS has since determined that less extensive remining and creation of an <br />engineered fill slope to improve visual aesthetics in this area made better economic and operational sense. This <br />is mainly because of the difficult access to remine original highwalls high up the slope and the need to "waste" <br />excess sandy soil byproducts of the mining operation. <br />As stated in the previous Amendment No. 4, the site was annexed into Morrison (the Town) to create apublic- <br />private partnership that will create the opportunity for Morrison and CAMAS to store raw water in bedrock <br />reservoirs at the site. The Town requested options on two reservoir sites: the temporary Central Quarry <br />Reservoir and the permanent North Quarry Reservoir. The Central Quarry Reservoir will have a minimum <br />capacity of 500 acre ft (ac-ft) and will be conveyed to the Town in the year 2000 pending final commitment <br />to construction of the reservoir by the Town in 1998. The North Quarry Reservoir will have a minimum <br />capacity of approximately 1,500 ac-ft and will not be available for approximately IS to 20 years. Final design <br />and construction of the reservoirs and appurtenant raw water system facilities will be undertaken jointly by <br />CAMAS and the Town. <br />The expansion of the South Quarry to the west and changes in the North Quarry mine planning and <br />reclamation are the rationale for this amendment to the mining and reclamation plan for the Morrison Quany. <br />4-02. GENERAL APPROACH TO MINING <br />Mining and reclamation will proceed from the present configuration in four major phases which will be <br />employed to: l}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 are the most aggressive configurations which are <br />G:WROIECfS~20ZIXIO0TiEX1~A1.ffNpOS.TXr tV - t <br />