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Mr. Berhan Keffelew <br />Re: Parkdale Quarry, Amendment #1; Adequacy Letter Response. <br />January 28, 2008 <br />Page 3 of 6 <br />7) The operator agrees to- compact the area around the fuel storage facility 1.0: feet by 20 <br />feet on each -side to at least 85-90% proctor to minimize- percolation in the event of a <br />spill. <br />8) The bridges over Tallahassee Creek are' intended to be temporary. The temporary <br />bridge sections based on available survey is included in Exhibit 111.8. The temporary <br />bridges over Tallahassee Creek were originally reviewed by the Division of Wildlife and <br />approved by the Army Corps of Engineers. Both the original Division of Wildlife review <br />and the Army Corps of Engineers authorization are. also included in Exhibit 111.8. The <br />bond calculations have been revised to include the cost for removing and reclaiming the <br />area around the bridges. <br />9) The operator does not plan to construct additional berms along the Tallahassee Creek. <br />A typical berm cross section is included in Exhibit 111.9. Based, on typical. cross section <br />information and an estimated total berm length of 475 feet, for the granite quarry and an <br />estimated total berm length of 1,100 feet for the sand and gravel operation, the bond <br />calculations have been modified for the removal and reclamation of these berms. <br />10) Atypical dewatering trench cross section -is included in Exhibit -III.10.' The bond <br />calculations have been modified. to include the removal and reclamation of the <br />dewatering trench. Calculations are based on an exposed water surface of approximately <br />one acre as stated in the Parkdale Quarry Amendment #1; Exhibit G Water Information.' <br />Based on the typical trench cross section, the length of the dewatering trench is estimated <br />to be approximately 2,420 feet in length. It must be noted that as mining progresses, the <br />dewatering trenches and associated pump locations will be relocated. The. dewatering <br />trench cross section illustrates the maximum trench dimensions 'anticipated and will <br />generally remain unchanged. <br />11) Details for the stormwater pond for the -granite quarry north of the proposed :facility <br />are identified in the "Stormwater Drainage Plan and Report - Amendment #1," which is <br />included in Exhibit 'III.11. The drainage report determined that the stormwater sediment <br />pond must have a minimum volume of 0.477 acre-feet and is expected to have a surface <br />area of approximately 0.6 acres. This stormwater pond accounts for the impediment <br />presented by the proposed processing facility. The stormwater pond will be located at the <br />inlet of an approximately 540-foot long corrugated metal pipe culvert that is 72-inches in <br />diameter. This corrugated metal pipe. culvert ? will be used to convey storm water to , <br />Tallahassee Creek. The natural drainage channel will be effectively restored. The bond - <br />has been revised to include the removal of the culvert and stormwater pond. <br />12) No permanent structures will be placed in the quarry processing facility. Temporary <br />structures have been included in the bond calculation. <br />13) The four mining phases in the granite mining operation will be implemented within <br />the three geographic areas of the quarry.' The first three phases are located within their <br />respective areas (i.e. Phase I takes place within Area 1, Phase II takes place within Area <br />2, and Phase III takes place within Area 3)'. Mining for Phases I, II, and III will open up <br />the quarry to the limits of mining and excavate down to a platform at an elevation of <br />between 5,700 feet and 5,800 feet. Phase IV mining will incise the quarry below the <br />platform level to a bottom elevation of 5,300 feet. within the previously mined area. <br />Reclamation within the area mined in Phase lV. will be_ with a reservoir.