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Mr. Gregg Squire • • Page 4 December 20, 2000 require additional stabilization, then bank armoring will be installed per the 150 ft. barrier armoring detail only in those areas requiring stabilization. The erosion protection on the upstream 150 feet barrier will be left in place after mining is completed to keep the barrier stabilized. The post mining contours are expected to be very similar to the pit contours until the river begins to recharge the mined out area. There is no way to model what the post mining contours will look like since the river action is not predictable. For this reason no post mining contours are shown except the 3:1 slopes left along the banks during mining. [tern 5 -Reclamation of wetlands areas disturbed by mining. The operator is in the process of submitting an Army Corps of Engineers 404 permit application and will revise the permit for the wetlands reclatation when the final reclamation plan is approved by the Army Cotps of Engineers. The operator recognizes the need to segregate topsoil from existing wetland areas from non-wetland areas and will incorporate this into the Army Corps of Engineers wetland reclamation plan. Item 6 -Setback width to the CDOT right-of--way. The depths of the pits along the CDOT right-of--way in the West End Pit range from 37 to 43 feet. The pit crest in the West End mining area is located along the toe of the bench that contains the frontage road. The distance from the pit crest to the CDOT right-of--way line ranges from 65 feet to 101 feet. The distance from the pit crest to the edge of the frontage road in these areas ranges from 134 feet to 172 feet. This distance provides a factor of safety in excess of the 2:1 ratio recommended by the Division. Item 7 -The potential for river capture by pits during flooding. Looking at the topographic mapping for the project site from 1982 and 1999, the following observations are made: 1. In 1982, the proposed renewable resource area was part of the main river channel. (See the previously submitted floodplain maps.) 2. The area that contains the proposed West Property Line to Horse Fence, Slough to East Property Line and Dry Creek mining areas appears to be an area that is flooded by a 100 year flood. 3. The natural flow of the flood in this area is to the south until the bank of the frontage road directs the floodwaters to the west until the high ground in the Dry Creek mining area directs the floodwaters back to the river where they reenter the main channel on the upstream side of the high voltage lines that cross the river. This point is approximately 3800 feet upstream and on the opposite side of the river from the water intake for the City of Rifle. 4. Based on the Garfield County floodplain maps, the depth of flooding ranges from 0.3 feet to 4 feet. 5. The surface facility portion of the Dry Creek mining area and the east half of the West End mining area are out of the 100 year floodplain.