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~ ! sediment pond berm outslopes and disturbed I,~ound within the sediment containment basin. Inorganic fertilizer will be applied at the time of seeding at rates equivalent to 100# Nitrogen and 80# Phosphorus. Seeding rates will be in the range of 40 # pls/acre. All seeded areas will be mulched with 4000#/acre clean straw mulch to promote moisture retention and vegetative establishment. Most of the construction will result in permanent stormwater control structures that will remain intact afrer completion of mining. As soon as the mine operator can establish self-sustaining vegetation on the disturbed areas (3-5 yrs) , T.H. E. will apply for bond release on the appropriate acreage under permanent reclamation. RESPONSE TO TECHNICAL INFORMATION AS REQUESTED 1) Stormwater Run-offCaicu{ations--disturbed area watershed including SWMP acreage l0yr SCSIJ 24hr Peak Discharge Discharge Volume 27.56 cfs 4.52 acre fr 100yr SCS1124hr 77.56 cfs 12.26 acre fr Stormwater Run-off Calculation--Undisturbed upland watershed area 145 acres l0yr SCSII 24hr Peak Discharge Discharge Volume 66.64 cfs ]0.95 acre ft 2. Average annual sediment loss from the disturbed area. 100yr SCSII 24hr 187.46 cfs 29.65 acre ft At the completion of sediment pond construction, seven collection basins will be in operation. The annual estimated sediment loss from the disturbed (mining zone) is 250 tons, moaot of which- will be collected in the Srst #5 sediment pond in the SWMP area. Less than 5% of the annual loss from the disturbed area is estimated to be collected in #2, #3, and #4 sediment ponds. A zero release of sediments from the affected land boundaries is anticipated with this S~VMP. 3. Engineering Designs--Please find attached design drawings and construction details ofall structures proposed in this SWMP. Plan views showing location and routing of all SN/MP structures can be found on the "Stormwater Drainage Map" 1": 200' topographic included with this package. 8