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2. Construct the pump station, outlet ditch, and Parshall flume as indicated on Figure 3.1 <br />following the reclamation of Pond 4. <br />3. Proceed with future mining as necessary to meet mitigation requirements, bearing in <br />mind the locations and areas of the proposed ponds and wetlands on Figure 3.1. <br />4. Install 12 inch gated culverts with concrete inlet headwalls between ponds as each <br />adjacent pond is excavated and reclaimed. <br />5. As mining approaches the northeast border with the Poudre River, construct the grade <br />control structure outlined in the Ayres Associates Report included as Appendix A. <br />Immediate construction of the pump station .and outlet ditch is not necessary for the <br />operation of the SWSP, which we will discuss later, but it will complete the construction <br />required for the final layout of Pond 4. Initially, since it takes only one 465 GPM pump to <br />operate the SWSP or the Augmentation Plan, both foundations for the pumps could be <br />constructed, but only one installed. We recommend completing the pumping station, outlet ditch <br />and flume soon after the reclamation of Pond 4, since it would eliminate the need for portable <br />pumping and water metering required for the administration of the SWSP. <br />5.3 Procedure for Future Mining <br />Currently the Timnath Pit is approaching the conclusion of mining operations in mining <br />Phase lA (See Figure 2.1). Concurrent with the completion of this phase, Kehn will have to <br />establish temporary wetlands sufficient to meet concurrent mitigation requirements as agreed <br />with the COE. The original concurrent mitigation requirement in the 404 permit was 63.8 acres; <br />however, this number may change based upon the amended permit request to the COE. We <br />recommend that Kehn come into compliance with COE requirements as soon as possible. The <br />construction of temporary wetlands is expensive and should be repeated as few times, as <br />necessary. Unfortunately, if Kehn wishes to mine the whole extent of the mining area, moving <br />temporary wetlands as mining progresses could be a problem. In the proposed final layout, we <br />have presented in this paper the permanent compensatory wetlands that are located in Phases.lB, <br />1C, 4, and portions of Phases 3 and lA. In order to eliminate the needless construction of <br />temporary wetlands, we recommend the following procedure, based upon the original mining <br />phase map shown in Figure 2.1. <br />1. Construct permanent wetlands per the proposed layout during reclamation of Phase lA. <br />2. Construct temporary wetlands in Phases 1B, 3, 4 and southwest corner of Phase 2 as <br />necessary to meet COE requirement. <br />T.•IOPENICodkcOllcodkc0l finnlrepor•l.doc 21 • ANdERSON CONSU~TINC~ ENGINEERS, ANC. <br />