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not appear to show the designation for a vegetated ditch. If you agree, please add the <br />vegetated ditch designation to the information on ditches DCW-8A and DCW-8b in <br />Table 44. <br />39. The SEDCAD designs for ditches above the RPE, DCW-8A and DCW-8B, are only for <br />the 10 year-24 hour precipitation event. If these two ditches are to serve as upland <br />diversion ditches for the refuse pile, either as the sole diversion ditches or in conjunction <br />with lower gradient diversion ditches, all of the runoff from the 100 yeaz-24 hour event <br />needs to be accounted for and diverted. Please explain how all of the runoff from the 100 <br />year-24 hour event is diverted from the RPE. <br />40. The SEDCAD run for the RPE pond cells A and B show a capacity of 4.59 ac-fr and 3.42 <br />ac-ft respectively. However, on Figure L-2 in Appendix L of Volume l OB, the capacities <br />are listed as 5.44 ac-ft and 3.65 ac-fr respectively. Please reconcile this difference. <br />41. The Division is unable to locate the as-built certification for the RPE pond. Please <br />provide this certification. <br />42. It is stated on Figure L-2 in Appendix L of Volume ] OB that the 8 inch pvc pipe for cell <br />A of the RPE sediment pond, which passes water to cell B, is 1 foot off of the pond <br />bottom. It is further stated that the 30 inch CMP emergency spillway is at a 2 foot depth. <br />If, by depth, it is meant that the culvert is 2 feet off of the bottom, then there would be a 1 <br />foot separation between the primary and emergency spillways. However, the SEDCAD <br />run for cell A of the RPE sediment pond shows the primary and emergency spillways are <br />at elevations of 6100.5 and 6103.0 feet respectively, a separation of 2.5 feet between <br />them. Please'reconcile these apparent differences in the elevations of the two spillways <br />for cell A. <br />43. [t is stated on Figure L-2 in Appendix L of Volume 1 OB that there is an 8 inch pvc pipe <br />and a 30 inch CMP emergency spillway pipe for cell A of the RPE sediment pond. <br />However, the SEDCAD run for cell A shows that both discharge structures are drop inlets <br />and that each of their diameters is 12 inches. Please explain. <br />c:\wp61 \westelk\tr86mem 1 <br />m:\coal\j rb\tr86mem 1 <br />CC- Ln kry~ ~o vTrE ~.) <br />