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A copy of the most recent Table 44 is appended. Nomographs for the two 18 inch culverts placed in the emergency spillway of FW-1 are appended and will be incorporated into Exhibit 66. 5. Ditch DCW-2 is proposed to be a permanent diversion, but not in the current constructed form. MCC plans to remove the shotcreted ditch during road removal during final mine reclamation. The post-reclamation ditch will be a vegetated ditch with gently sloping banks. The constructed configuration of the permanent DCW-2 will be adequate to safely pass the 100-year precipitation event peak runoff, as is the current configuration. 6. MCC reviewed pump records for 1992, 1993, and 1994 for Portals 2 and 5 (the only portals which discharge) to determine the average amount of mine inflow pumped (present) in pond MB-1 at any given time. The minimum volume of water pumped into MB-1 was from Portal # 5 which consistently had no discharge from 1992 through 1994. The maximum discharge was from Portal # 2 during the month of January 1994, measured at 1,585,800 gallons (4.86 ac-ft.). The average volume of mine water present in the pond during a monthly basis is 1,039,009 gallons or 3.19 acre-feet. The design storage capacity of pond MB-1 is 9.62 acre-feet. The design storage volume for the 10-year, 24-hour precipitation event is 1.86 acre-feet. The design volume for three years of sediment storage is 0.09 acre-feet. Based on this information, available storage during the maximum period of pumping was 4.67 ac-ft. (assuming maximum sediment storage), sufficient to store 2.51 10-year, 24- hour precipitation events. During average conditions, available storage is 6.34 ac-ft. (assuming maximum sediment storage), sufficient to store 3.41 10-year, 24- hour precipitation events. From this information it is clear that there is more than adequate storage capacity in pond MB-1. Mine inflow was also considered in the design of pond MB-l, with the use of the SEDCAD+ program. CDMG is referred to Exhibit 66, Pond MB-1 SEDCAD+ Input Table, in which 0.5 cfs of inflow was added as baseflow in the fast node. 7. Ditch Dl-3B dces not exist. MCC believes confusion arose from mislabeling on an Envirocon drawing. On this drawing the ditch should have been correctly identified as D1-3D, not D1-3B. Ditch DI-3C dces not exist and will not be constructed. This ditch, originally proposed on the north side of the substation, was replaced by the French drain system depicted on Map 54. 8. Ditch D1-3C dces not exist and will not be constructed. This ditch, originally proposed on the north side of the substation, was replaced by the French drain system depicted on Map 54. -3-