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THIRD ROUND ADEQUACY REVIEW COMMENTS - TR-63 <br />The following are the new questions based on Colowyo's responses to adequacy question <br />5,6,7and10. <br />16. The Division did not find a channel profile for the North Tributary of East Pit <br />Ditch in the response package. Please submit for incorporation into the permit <br />the channel profile for the North Tributary of the East Pit Ditch. <br />Response: Map 33 has been modified to provide the profile for the North Tributary of <br />the East Pit Ditch. <br />17. The Division requests that an additional table be developed that identifies, at <br />a minimum, the permanent ditch name, riprap sizing, bottom width, channel <br />depth, "from" station, "to" station, calculated peak discharge, and estimated <br />maximum peak discharge that the channel could handle given the proposed <br />riprap size. <br />Response: Table 1 is included which summaries the channel design information of <br />Exhibit 7, Item 14. A text reference to this table has also been added on page Exh. 7- <br />14-6. It should be noted that the riprap size specified in this table is the minimize size <br />specified by the design, based on the predicted peak flow. The maximum peak <br />discharge the channel could handle is not provided in the table, although this information <br />is available by reviewing the graphs provided in Figures 1 through 4 of Exh. 7-14H. <br />18. Monitoring of the permanent channels in the reclaimed area is not currently <br />included as a requirement of the annual rill and gully survey. Please <br />incorporate monitoring commitments in the rill and gully plan, or permit <br />text, to for reconstructed channels on a periodic basis and after large storm <br />events or snowmelt episodes. <br />Response: The permanent channels have been properly designed in accordance <br />with Rules 4.05.3 and 4.05.4 for each of the drainage areas involved. Colowyo has <br />never had any erosional issues with any of the permanent channels and does not deem <br />this monitoring to be necessary based on an operational history of more than 25 years. <br />19. The Division has seen numerous examples of side-cutting of riprap channels <br />due to improper installation. Please incorporate a generalized design cross- <br />section that shows the planned installation of the riprap channel to avoid or <br />minimize side-cutting due to slope runoff adjacent to the channel. <br />Response: Examples of these generalized design cross-sections can be found in the <br />existing permit document, Volume 2C, Exhibit 7, Item 14, Parts 2C through 2G on the <br />first page of each section. Following approval of TR-63 and the generalized approach <br />