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Response: The riprap sizing method is shown on Figure 1-1, Median <br />• Riprap Diameter for Straight Trapezoidal Channels. <br />The riprap has been sized for both Segments 1 and 2 of the channel <br />for Ditch No. 1. Table 1, Thickness Requirements for Granular <br />Bedding, and Table 2, Classification and Gradation of Ordinary <br />Riprap of the April 15, 1985 Adequacy Response, show the size <br />distribution of the selected riprap. <br />Bedding material and riprap will be placed utilizing front end <br />loaders and crawler tractors to form the channel. Where bed rock <br />is encountered, bedding material and riprap will not be utilized. <br />Riprap will be placed on side slopes and bends to protect the <br />channel and provide the necessary armoring to maintain the channel <br />in a condition to pass the design flow. <br />Peerless has investigated the possibility of altering the channel <br />and does not consider it economically feasible. The channel. bed <br />has been constructed in accordance with the design and is located <br />on bedrock in many places. Therefore, additional excavation would <br />require drilling and blasting which is not realistically feasible. <br />e. The applicant should include the upstream Coal Gulch stream <br />channel cross-section. <br />Response: Figure 1-2, Coal Gulch Channel Cross-Section, shows the <br />existing upstream channel of Coal Gulch. <br />f. The Division concurs with the applicant that. the channel is <br />adequately designed to handle the additional flows which will <br />result upon site reclamation, however, there is no commitment <br />to any freeboard found in the application or channel design. <br />Response: The channel has been designed for 1.5 feet of freeboard. <br />-4- <br />