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Division of Minerals and Geology (DMG) Response- The operator is proposing a lh:ly slope on the mining face. When the mining face is reclaimed, it will be stripped and cleaned of claystone bedrock and be processed and recompacted in lifts to a finished slope of 4h:1 v. 5. "Considerable additional information is needed concerning the northern two "Silt Ponds" adjacent to the CDOT ROW, at the north end of the affected area. Mining Plan Map 3 indicates that they will be mined. 1) There is no mention or indication of what the set back is for this area. 2) Will the mined slopes be left 1:2? 3) Will they be lined? 4) What is the purpose of the silt ponds? 5) Will the silt be removed or will it just be left as super saturated material? 6) What is the final reclamation of these two areas?" (Colorado Department of Transportation; March 26, 2005) Division of Minerals and Geology (DMG) Response- The setback from the settling pond adjacent to CDOT right-of--way at the north end of the affected azea will be 100 feet from the CDOT right-of--way (measured from the toe of the slope). The off-set distance has been added as a note to the mining plan map. The mined slopes will be left at lh:ly. Silt fines from dewatering/processing water will settle out so that the water can be reused in the processing operations, or so that it can be discharged off-site (in accordance with a Colorado Discharge Pernrit System permit). The end use for the reclaimed silt ponds will be upland pastureland. The silt ponds will be allowed to fill within about 12" of the existing surface elevations. The operator will apply 12" of topsoil and seed the area according to the seed schedule on the reclamation landscape plan map. This area will be graded consistent with existing pre-mining conditions. The postmining land use for the silt pond area is proposed to be upland pastureland. Application Exhibit E- Reclamation Plan: 6. "Mining Landscape Plan Maps 4, and 5 show that trees and shmbs are to be planted along the property line adjacent to CDOT ROW. Our primary concerns with this are drifting snow and maintenance problems created when bushes, shmbs, and evergreen trees are so close to the property line that they grow through the fence, catch trash, and have to be trimmed. Can these concerns be considered when developing the landscaping plan?" (Colorado Department of Transportation; March 26, 1005) Division of Minerals and Geology (DMG) Response- The applicant revised the application to state that "all trees along State Highway 85 shall be planted on SW TKO Joint Venture property so that the dripline of the trees does not extend into CDOTcight-of--way at maturity. "Paragraph (a) of the Reclamation plan shows that 4 water storage ponds are proposed ranging in size from 23 acres to 94 acres. They total approximately 277 acres of surface area. Reclamation plan, map 6, shows two ponds, one at 86.4 acres and one at 175 acres. There is also an azea labeled 19.3-acre wetland/pond area. Which is correct, the narrative or the map? Our concern is with the amount of wave action erosion that can be created by wind blowing over % mile of open water." (Colorado Department of Transportation; March 16, 2005) Division of Minerals and Geology (DMG) Response- The revised Reclamation Plan Map dated April 18, 2005 includes a 82.5-acre lined pond and a 175-acre lined pond. The remaining land, including silt ponds, will be reclaimed as upland pastureland. In response to the wave action from erosion, the applicant states that the proposed maximum water surface elevation far Pond 2 (closest to Highway 85) is 4,937.5 ft-MSL. The ground surface along the western margin of Pond 2, parallel to Highway 85, ranges in elevations from 4,940 ft-MSL to 4,944 ft-MSL, This provides freeboard ranging from 2.5 feet to 6.5 feet at the maximum water surface level. The embankment will be zoned with an inner core of low-permeability clay material (Zone 1) and a twelve-foot wide (measured horizontally) zone of erosion protection (Zone 2). According to the applicant, the Zone 2 material has been approved for jurisdictional dams by the State Engineers Office as a recognized erosion control measure. The project will include the Zone 2 clayey gravel soil containing awell-graded mixture of 12" of sand, gravel, and cobbles left behind from mining operations and 6" of weathered claystone bedrock. Where the gravel and cobble layer is less than 12", additional pit mn will be added. Should any wave erosion occur along the reclaimed pond slopes, the applicant will be required to submit an erosion control