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<br />r] <br />miles downstream as the applicant has said. The Golden Eagles are nesting less than I/4 mile <br />south of the mine site." (Van Norstrand; April 5 & May 8, 2001) <br />DMG Response -The applicant has provided written verification that representatives of the <br />Colorado Division of Wildlife have reviewed the application and plans for the proposed mining <br />operation, have inspected the proposed site and surrounding area, and find no evidence to <br />substantiate the assertion of nearby nesting eagles. The DOW has also not provided any written <br />evidence of possible negative impacts to fish and/or wildlife in the affected land or surrounding <br />area. <br />Issues Raised After The Initial Public Comment Period <br />(During the Informal Conference Comment Period) <br />Exhibit G- Water Information: <br />5. " ... wrong floodplain information." (Landers; June l4, 2001) <br />DMG Response -The applicant has conducted and provided an engineering analysis to predict <br />the locations of the floodways of Trout Creek and the Yampa River in the vicinity of the <br />proposed operation. The floodways were determined with HEC-RAS v. 2.2 Analysis using site <br />specific, surveyed cross-sections. The method of "equal conveyance" (HEC-RAS encroachment <br />method 4) and a maximum allowable rise of 1.0 feet, as defined by FEMA for determination of <br />the floodway, was used to determine the lateral limits of the floodway. Aeral adjustments and <br />flow inputs were used based on the location of appropriate USGS gauging stations, per the USGS <br />web site. The engineering analysis verifies that all pit excavations will be outside the limits of <br />the floodways for Trout Creek and [he Yampa River. <br />Trout Creek is extemely stable. Evidence of streambank erosion, indicative of a stream's <br />tendency to migrate laterally, is virtually non-exis[ant. The engineering flood analysis performed <br />on Trout Creek for the proposed operation showed that the 100-year flood flows are contained <br />within the banks of Trout Creek. The proposed 50' setback from the streambank of Trout Creek <br />should be more than sufficient to keep Trout Creek from entering into the pit. The Yampa River <br />will be 200 - 250' or more away from the northernmost edge of the proposed excavation. While <br />some lateral migration of the Yampa River at this location can occur, a buffer of 200 - 250' or <br />more is very large and should be more than adequate to minimize the potential for the river <br />entering the pit. Near bank veclocities in the river at this location during a 100-year flood event <br />are relaively slow, ie; typically 3-5 fps with a maximum of 6-8 fps. The combination of channel <br />shape along with the presence of gravels in the stream banks and moderate velocities indicate the <br />streambank is at a low risk of rapid lateral migration. Therefore, bank erosion of only a few feet <br />during a high water event can be expected. <br />