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The reclamation of the mine site and road (existing disturbance) will include establishing <br />stable ephemeral channels across the reclaimed area. The lower channels will be <br />excavated to conform to the dimensions of the channels immediately above and below the <br />disturbance. Munger Creek and the channel draining the major canyon south of the road <br />are currently diverted under the road with culverts. When the culverts are removed, dry <br />fords will be excavated and rip rap will be installed to minimize erosion. Rip-rap keys <br />will also be installed at the upstream and downstream edges of the ford. The gravel will <br />be reclaimed from the existing road where the road base is excavated in the process of <br />building the ford. The l0 inch gravel is coazse and will protect the channel bottom <br />between the rip-rap keys. <br />Eight different ephemeral drainages crosses the road on the upper portion of the mine. <br />They are labeled A through H and can be located in Figures 3.1-2 through 3.1-7 In most <br />cases, the original channel was filled during construction of the mine road. The <br />reclaimed channels are designed so that the flow would not increase erosion by installing <br />a channel wide enough that the peak flow will remain shallow. Rip-rap keys will be <br />installed at the top and bottom of each reclaimed channel, except for those areas where <br />rock outcrop is present. The rip-rap keys will ensure that the entrance and exit of each <br />reclaimed channel will not erode during high flow. <br />For discussion of backfilling and grading plans associated with proposed future <br />disturbance, the reader is referred to the Division's March 10, 1993 Findings of <br />Compliance. Pursuant to Stipulation No. 23, the plans described therein will be subject <br />to revision prior to resumption of active status at Munger Canyon. <br />IX. Revegetation <br />Baseline vegetation information for the Munger Canyon Mine can be found in Section <br />4.8 of Volume I, Sections 3.1.1 and 4.5 of Volume VI, and on Figure 4.5-]s of Volume <br />VII of the permit application. The Division has reviewed this portion of the application <br />and determined that the information is adequate. All previous concerns relating to the <br />baseline vegetation information section of the initial permanent program permit <br />application have been resolved. <br />In the initial sampling program undertaken, inadequate numbers of samples were taken to <br />provide the current desired levels of confidence (p greater than or equal to .80 for <br />non-herbaceous communities, d = .10, alpha = 2) for the productivity of the greaswood <br />shrubland, shadscale shrubland, andjuniper woodland vegetation types. <br />The Grand Valley Coal Company Munger Canyon Mine contains the same vegetative <br />communities (with the exception of the Big sagebrush community) as, and is located <br />contiguously to, the Grand Valley Coal Company McClane Canyon Mine. Abiotic <br />as <br />