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<br />-a- <br />In any case, some modification to the ditch designs will be necessary. <br />The Division recommends diverting all these flows away from the <br />disturbed area either through Ditch No. 2 or by extending the gulch to <br />meet Ditch No. 1. Peerless Resources may find that diverting flows to <br />Ditch No. 2 will eliminate the potential for flooding and seepage at <br />the portal and fan entries. <br />9. Where will Ditch No. 2 discharge and how will these flows reach the <br />existing drainage which is on the opposite side of Highway 160? <br />10. The disturbed area drainage as currently shown appears to be <br />approximately 10 acres larger than the number used in the drainage <br />calculations (making this area 38 acres instead of 28 acres). <br />11. The curve number 72, used for undisturbed acreage is too low. From the <br />presented data it is shown that this number was derived using a cover <br />of 75%. The cover does not appear that high and this curve number <br />should be revised to reflect the accurate percent cover. <br />12. How is water east of the pond going to be channelized into the pond? <br />It appears that this water will just pond against the berm and could <br />possible flow to the east and enter Ditch No. 2 which carries <br />undisturbed drainage. Please clarify. <br />13. The culvert nomograph used in the design of the principal spillway <br />should be presented. <br />14. The pond will need a dewatering device. It is believed that the <br />existing culvert will dewater the pond much too rapidly to serve as a <br />dewatering device. The pond should be dewatered in 24 to 36 hours. <br />15. It is not clear from the design whether the pond is excavated or <br />embanked or a portion of both. This should be clarified. <br />16. How are the flows channeled into the emergency spillway? As shown on <br />Figure 1, the spillway is approximately 20 feet from the top of the <br />embankment and it is not clear from the drawing how water will cross <br />this 20 feet. <br />17. What happens to flows once they exit the emergency spillway? How will <br />they be channelized to the existing drainage? <br />18. The principal and emergency spillway locations should be shown on Map <br />12. <br />19. The emergency spillway design is in error. The actual height of flow <br />is 0.81 feet, but may change based upon redesign in addressing some of <br />the above comments. <br />20. How will the flows from the emergency spillway get through the berm? <br />How will the flows get across the haul road from the west side of the <br />pond? <br />