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Surface Water Hydrology Review <br />17. In the table labeled "Appendix B" on proposed page App-139, there are several entries for peak <br />flows that do not correspond to those listed in the current or proposed designs. These peak flow <br />entries are for ditches F1, F2, F9, F11, F13, F14, F16, F17, F18, East Diversion, West Diversion <br />#1 and culvert F2. Except for ditch F2, it appears that the designs for these ditches and one culvert <br />were revised but not included in TR-64. Please provide the revised designs or revise proposed <br />Appendix B accordingly. <br />18. Comparison of currently approved Map 15-3, Map 21-3, Figure 1 and Figure 2 with the <br />comparable maps and figures that are proposed in TR-64 shows that the designation of the western <br />flowing extension of West Diversion Ditch #1 has been eliminated. Previous field inspections have <br />indicated that the West Diversion Ditch #1 had an eastern flowing component and a western <br />flowing component and that the western flowing component diverted undisturbed runoff to the <br />west, away from the western extent of the gob pile. Unless this situation has changed in the field, <br />please add this ditch designation back onto these two maps and these two figures. <br />19. The TR-64 submittal includes a proposed page Exh 8-20. However, the Division's copy of the <br />permit application for Exhibit 8 already has page Exh 8-20. It appears that this proposed page <br />should be Exh 8-19i. Please revise this page number accordingly. <br />20. In the table "V-Ditch Design" on proposed page Exh 8-29i, the peak flows for ditches D5, D6, D7 <br />and D8 do not correspond with the peak flows given in the new ditch designs. Please revise <br />accordingly. <br />21. In the table "V-Ditch Design" on proposed page Exh 8-29i, the design entries for ditch GVB7 <br />have been removed. However, this ditch still appears on Map 36B. Please add the GVB7 <br />information to the table or explain why the information was removed. <br />22. On proposed Figure 3, "Coal Mine Waste Disposal Area - Pond F Detail", please revise the ditch <br />depth and flow depth values for ditches UpDivWestl, UpDivWest2 and UpDivEast to conform to <br />the values obtained in the ditch designs. The ditch depths should be 1.5, 1.4 and 1.6 respectively <br />and the flow depths should be 0.5, 0.4 and 0.6 respectively. <br />23. On proposed Figure 3, "Coal Mine Waste Disposal Area - Pond F Detail" in Volume IX, please <br />revise the as-built pond F water volume, sediment volume and total pond volume values to <br />conform to the designed values shown on revised page App. B-4. The revised water volume, <br />sediment volume and total pond volume values are 3.66, 0.18 and 3.84 acre-feet respectively. <br />24. The design parameters for the required water volume, sediment volume and total volume have <br />changed for pond D as well. Volume IV and Drawing No. 95266-04 in Volume IV contain the <br />pond D design parameters but this information was done by Westec. Since the revised required <br />pond capacities are less than and close to the previous values, it does not appear to be worth the <br />effort to ask Westec to revise Volume IV or their pond D drawing. However, in order to avoid any <br />confusion, please add to page 2.05-29 of Volume I a reference to the pond D design information <br />located in Exhibit 8 of Volume III. <br />4