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David Berry -9- June 20, 1996 discharge event will be 5.25 feet per second. The DMG comments that this velocity may be erosive depending upon the material used in the emergency spillways. The DMG recommends that some type of erosion control material be used along the top of the emergency spillways. BRL's has decided not to place erosion material along the top of the emergency spillways for the following reasons; 1) the 5.25 fps velocity is only 5$ greater than the DMG's threshold velocity for erosion of 5 fps (adequacy comment #48); 2) the pond embankment and spillway will be seeded and the resulting vegetation should help stabilize against erosion; and 3) it is very unlikely that either of the ponds will see any discharge over their emergency spillways. 37. On page 17 of Exhibit 8, a hydraulic length of 1516 feet and an elevation change of 294 feet is given for the watershed # B-5 Wetland. The DMG indicates there is a wetland area at a hydraulic length of about 3400 feet and an elevation change of about 1050 feet. The DMG is correct. It must be noted that the B-5 Wetland area represents 1.9 acres of a 154.6 acre drainage area. Five separate wetland areas make up the 1.9 acre watershed. For simplicity, BRL did not break down the 1.9 acres of wetland into separate drainage areas. BRL picked one wetland to establish the hydraulic length and elevation change. If the DMG numbers were utilized, the peak flow calculation actually decreases. BRL does not believe it is necessary to revise the hydraulic length or elevation change for the B-5 Wetland watershed. 38. The DMG states that it appears the calculation of the total drainage area for drainage area D did not take into account the drainage area above the gob pile that is being diverted around the gob pile and into drainage area D (page Exh-8-21). The DMG is basically correct. However, the estimated flow from the gob pile upper diversion ditch is added into the structures affected by the ditch. Ditch D-D1 receives the flow from the gob pile upper diversion ditch. On page Exh-B- 12 the flow from the gob pile upper diversion ditch is added to the flow from area D to establish the peak flow for ditch D-D1. 39. On page 21 of Exhibit 8, an elevation change of 1690 feet is listed for watershed D-1. The DMG is correct that the elevation change should be 690 feet. This value was changed. Enclosed are revised pages Exh-8-12, Exh-8-13 and Exh-8-21. Based on this change the estimated peak flow for this watershed D-1 increased 0.76 cfs from 7.60 cfs to 8.36 cfs. 40. On page 21 of Exhibit 8, a hydraulic length of 1516 feet and an elevation change of 388 feet is given for watershed D-3 Juniper Woodland. The DMG indicates there is a Juniper Woodland area at a hydraulic length of about 3400 feet and an