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The CRDA-2 east and west channels end abruptly on page CRDA2-13a and Exhibit 51, <br />and do not appear to tie into any natural channels. Powderhorn should tie these channel <br />segments into natural drainages, and design and armor the transition zones where <br />necessary. <br />In Powderhorn's cover letter, they did not agree with the vegetated channel design for three <br />locations on the RSRDA south diversion ditch cited in NOV C-97-016. I used a vegetated <br />channel design of "B" stability and capacity class, whereas the operator believes that "D" <br />stability and capacity is more appropriate for a channel lined with cheatgrass. Cheatgrass <br />appeazs to be more closely related to other grasses in the "D" group rather than the "B" group. <br />changed the stability and capacity class to "D" for measurements IS-18 taken on the roadside <br />refuse pile. The four segments of the ditch will pass the designed flow, and will not be erosive. <br />They are attached for your refrence. <br />Please let me know if you or the operator have any questions. <br />c:\esc\misc\971229 <br />