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towards the middle of the pond since it is now positioned very close to the outlet of ditch NHN- <br />002 North. <br />30. Figures 1-4 of Appendix 2.05.3(3)-1 show that the sediment pond primary discharge pipes will <br />extend beyond the permit boundary. Please revise these figures to show that the discharge pipes <br />will not extend past the permit boundary. <br />31. The submitted pond designs are based only on the 10 year-24 hour precipitation event. Please <br />provide pond designs that also use the 25 year-24 hour precipitation event to show compliance <br />with Rule 4.05.9(7)(d) regarding the minimum elevation difference of one foot between the <br />design event water level flowing through the emergency spillway and the top of the <br />embankment. <br />32. Please confirm that the three riser pipe diameters are different than the barrel diameters for each <br />of the three sediment ponds. <br />33. Please revise the permit text and pond drawings to show that anti-piping barriers will be used <br />on the primary discharge pipes that go through the pond embankment, as required under Rule <br />4.05.9(2). <br />34. The Sedcad designs contain two runs for the "Collection Ditch Design for Pond NHN-002 <br />South". The first design run appears to have used parameters from the previous run for <br />"Collection Ditch Design for Pond NHN-002 North". Please eliminate the incorrect Sedcad <br />design run for NHN-002 South. <br />35. On Map 2.05.3(3)-l, Surface Water Hydrology, the acreage for subwatershed SW-MD is <br />shown as being 103.02 acres. This watershed is appropriate for the design of culvert C-6 but the <br />design of culvert C-6A should also take into account the subwatershed of Meehan Draw and <br />the undisturbed wetland. Please revise the Sedcad design for culvert C-6A accordingly. <br />36. As was done for the curve number of 91 on the second page of the Pond Design Memo in <br />Appendix 2.05.3(3)-1, please justify the use of the curve number of 79 for the subwatersheds <br />for culverts C-6 and C-6A. <br />37. Please designate the extent of the riprapped section of ditch NHN-002 South Riprap on Map <br />2.05.3(3)-1. <br />38. Please explain how all of the runoff from a subwatershed, such as SW3-A, can get to the exit <br />culvert of the subwatershed, such as culvert C-7, without downgradient cross ditches that <br />would bring the runoff to the culvert. <br />39. Please explain how the upgradient runoff will be diverted around the disturbed area perimeter <br />collection ditches. <br />5