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4. Please provide an updated page 2.05 -44 to include discussions of the Temporary Stockpile as approved by MR- <br />117. <br />NECC: Page 2.05 -44 has been revised to include discussions of the temporary stockpile approved by MR -117. Also, <br />reference to Exhibit 42 was changed to Exhibit 43. No content has changed in the report, therefore, only the cover <br />page will be supplied. <br />Division: DIVISION RESPONSE TO BE DETERMINED. <br />5. NECC must provide a plan for controlling runoff, particularly energy dissipation, once it flows through ditch D49 <br />and onto the Parks and Wildlife property. Also, a field inspection from early May 2012 reveals that the drainage <br />culvert on CPW's property which would relieve the runoff from ditch D49 has been buried. Finally, the Division <br />requests that NECC contact Colorado Parks and Wildlife (CPW) regarding the discharge point of ditch D49. <br />NECC: A temporary use agreement has been submitted to CPW to address energy dissipation of D49 once it leaves <br />NECC property. The plan includes extending D49 by approximately 60', plating it with 15" riprap and then <br />discharging into a 36" culvert, C85. The proposed arrangement can be seen on Map 14 and ditch and culvert <br />design shown on Tables 20 and 21, respectively. CPW approval will be submitted to DRMS once it is obtained. <br />Division: Per Table 20, the peak discharge in Ditch 49 (12 %) is 72.33 cfs. If this flows into culvert C85, why is the <br />flow for C85 in Table 21 only 33.51 cfs? <br />NECC needs to submit a copy of the signed (not the draft) temporary use agreement, for insertion into the Right of <br />Entry (Rule 2.03.6) section of the New Elk PAP. Preferably, this will be done before the Division decision on this <br />technical revision. <br />6. The ditch D49 SEDCAD printout is unclear. In the time of concentration details (page EXH 19(22) -49), there are <br />two times listed for SWS #2 for Structure #2: 0.055 hour and 0.377 hour. Please explain. It would be very useful <br />(but not necessary) to provide a schematic and/or map showing structures, sub - watersheds, and flow paths for D49 <br />and other ditches. <br />NECC: There are two subwatersheds for Structure #2. One subwatershed is associated with the upland area, the other <br />is associated with the disturbed are that is contributing flow to the channel. The large majority of the runoff in <br />ditch D49 is from the upland area, however, there is a small portion of runoff that will be generated from the berm <br />that will be constructed between D49 and the various portions of the collection ditch in the outslope of the waste <br />pile. <br />Division: This portion of the model is still unclear. The NECC explanation does not address why there are two times <br />listed for SWS #2. Furthermore, the Subwatershed Hydrology Detail table lists three SWSs, not two. <br />7. The location where ditch D49 would originate was inspected. Please provide more details on the design of the <br />upper end of this ditch to determine if it is sufficient to prevent flow down the drainage from impacting the <br />proposed DWDA. Additionally, it appears that the proposed location of ditch D49 pre- disturbance goes up- <br />gradient at the upper section. Does NECC plan on cutting the slope back or cutting the ditch deep enough to <br />2 <br />