Laserfiche WebLink
2 . The 6" CMP gated spillway was not constructed. It was <br /> to be used for releases, but all excess water from this pond <br /> will be pumped out. <br /> 3. The coal storage bin was requested for a small area <br /> exemption. Please see Volume 7 , Chap. V, Pages 2 and 3. We <br /> would like to add to that the Southeast corner of the mine <br /> pad. See enclosed sketch for details. <br /> 4 . Prior to reactivation of Mine No. 4 , the permittee will <br /> construct the sediment ponds, as designed, on the southeast <br /> side of the Mine No. 4 bench. <br /> Mine No. 5 <br /> 1. Parent equation, Bernoullis for orifices Q=Ca <br /> 2 gh Handbook of Hydraulics by King and Brater, Chap. 3, <br /> Pages 3 and 4. <br /> 2. Designs, Diversions, Ditches. Exhibit 5-2. All <br /> calculations are for 10 year, 24 hour event. <br /> a. Area 5-1 - Berm at base of highwall (clean water <br /> diversion) 2 'x5 ' see Exhibit Plan 5-1. The slope is less <br /> than 1. 0% so we feel this ditch would be more than adequate. <br /> Easterly of two culverts - The area above the <br /> culvert is approximately 200 'x400 ' or 1. 8 ac. of forest, <br /> slope 20% , CN=80. , CFS4 . 3 . The 18" culvert installed has a <br /> slope of 0. 02 , which gives a discharge of 10. + CFS, giving <br /> sufficient room for bulking. <br /> Westerly of two culverts - The area above the <br /> culvert is approximtately 300 'x300 ' or 2. 1 ac. of grass and <br /> shrubs , slope 20% CN=80, CFS=4. 9. The culvert installed has <br /> a slope of 0. 01 which gives a discharge of 7. 0+ cfs. <br /> b. Area 5-1 long northwest ditch from pad to pond. <br /> Length 1300 '+. Average slope 0.10, gravelly silty soil, CN <br /> 90. , disturbed area = 5. 16 ac. , Q+16. 8. Ditch capacity <br /> 24.cfs @ ID, FDS with lots of freeboard for bulking. All <br /> areas above 2-3 FPS will be riprapped. (See sketch of <br /> typical ditch size) . <br /> General <br /> 1. Gage boards will be installed in each pond. <br /> 2 . Certification report will be forthcoming. <br /> Sincerely, <br /> Dou as Bowman <br /> Environmental Coordinator <br /> DB:rm <br /> 66 <br />