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12/20/79 Memo, p. 4, $10 "10. The permanent ditches associated with excess spoil pile #1, and ditch 2b-2 are located along hillsides. When the design storm is exceeded, these diversions would, in all likelihood, change their courses. The diversions should be relocated to lower topographic positions where they would remain in position even under excessive flow conditions." The permanent diversion ditches will be relocated from the natural hillsides to the toe of the fill. The hydraulic design criteria for the relocated ditches can be found in the revised Figure 32, Permanent Diversion Structures. Since EFC has proposed to construct spoil pile 2a rather than 2b, there will be no more reference to permanent diversion ditches 2b-1 and 2b-2. 12/20/79 Memo, p. 4, 5, X11 "11. A preliminary review of the proposed post-mining topography with respect to Approximate Original Contour and susceptibility to erosion has been completed. Other than the following item ($12) there appear to be no major problems. However, I am reserving a final review until after the information requested has been supplied, and any issues concerning permanent spoil piles have been resolved." This statement requires no response. 12/20/79 Memo, p. 5, $12 "12. The application proposes to recreate ephemeral drainages crossing the disturbed area. However, no information has been provided on the design of the restored stream channels. Cross-section B, which follows a restored valley at its lower end, suggests that at least one stream is oversteepened. This could lead to erosion problems. The applicant should provide a detailed plan for the reconstruction of stream drainages including pre-and post-mining longitudinal profiles, stream cross-sections, and design flows". See pp. 780-154(a)-(c), 816-127(a)-(r)