2020-03-24_PERMIT FILE - C1981019A (41)

Home Browse Search

TABLE 6 COLOWYO COAL COMPANY SEDIMENTATION POND SUMMARY PROPOSED PLAN SECTION 16 EAST TAYLOR EAST TAYLOR STREETER WORK AREA GOSSARD STOKER SIDING RAIL LOOP PROSPECT WEST PIT POND POND POND POND POND POND POND POND POND POND Post Mining Active Mining Post Mining WATERSHED SREA(acres): Disturbed 00 00 00 00 00 00 00 00 00 00 Postmmmg Topsoiled and Seeded 436 8 108 3 25 9 14 5 5 7 103 8 87 5 21 9 106 2 82 2 Undisturbed-Phase III Released 795 9 13 2 0 0 0 0 0 0 236 8 23 2 125 6 49 8 70 4 1-2 Year Reclamation 00 00 00 00 00 2314 00 811 766 1662 3+Year Reds melon 1418 00 00 00 00 1289 888 395 4183 7575 Total Area 1374 5 121 4 25 9 14 5 5 7 701 0 199 5 268 1 650 9 1076 3 'POND PARAM ETERS: Bottom Elena on 6578 0 7146 0 6384 9 6321 8 6344 0 6734 0 6821 0 7740 2 6930 0 6930 0 Principal Spillway Invert Elevation 6585.0 7155 8 6391 0 6329 6 6351 5 6750 3 6837 0 7752 9 6952 0 6951 0 ail Emergency Spillway Invert Elevation 6588.0 7158 0 6392 7 6332 0 6353 0 6752 0 6838 0 7754 5 6954 0 6953 5 Top of Embarkment 6591 0 7160 0 6400 9 6334 0 6355 0 6755 0 6841 0 7756 0 6956 0 6956 0 Storage Volune Below Emergency Spillway Invert(ac-ft) 11 2 23 2 4 3 3 2 1 5 6 1 13 8 5 4 9 1 8 6 I Storage Volume Below Pnncipal Spillway Invert(ac-ft) 5 2 17 0 3 0 1 9 1 0 5 1 12 6 4 4 7 5 6 7 Storage Volume Below Lowest Spillway Perforation(ac-ft) 2 63 12 33 N/A 0 38 N/A 2 25 5 50 1 26 2 85 2 85 Pnncipal Spillway Parameters Type Pert Riser Pert Riser Fixed Siphon Pert Riser Tnckle Tube Pert Riser Pert.Riser Pert Riser Pert Riser Pert Riser ' Riser Dame er(in) 120 120 N/A 120 N/A 120 180 120 180 180 Riser Height(ft) 3 7 5 1 N/A 5 7 N/A 8 7 11 6 9 2 10 0 10 0 Barrel Diamrter(in) 18 0 12 0 6 0 12 0 8 0 12 0 18 0 12 0 18 0 18 0 Elevation of°erforation(s)(ft) 6583 0 7154 0 N/A 6325 0 N/A 6744 0 6830 0 7746 0 6944 0 6944 0 Size of Perforation(s)(in) 4 0 4 0 N/A 4 0 N/A 4 0 4 0 4 0 4 0 4 0 Number of Perforations 2 0 3 0 N/A 1 0 N/A 2 0 3 0 2 0 2 0 2 0 Emergency Spillway Parameters- Type Trapezoidal Trapezoidal Tnckle Tube Trapezoidal Trapezoidal Trapezoidal Trapezoidal Trapezoidal Trapezoidal Trapezoidal Diameter(in' N/A N/A 30 0 N/A N/A N/A N/A N/A N/A N/A Bottom Widti(ft) 200 150 N/A 50 70 120 240 190 200 200 Length(ft) 50 0 140 0 155 0 40 0 15 0 20 0 21 0 17 0 20.0 20 0 Side Slopes z'H 1V(ft) 1 5 1 5 N/A 2 0 2 0 1 5 1 5 2 0 2 0 2 0 HYDROLOGIC.HYDRAULIC PARAMETERS: Base Flow Ra es(cfs) 0 00 0 00 0 00 0 00 0 00 0 15 0 03 0 00 0 00 000 10-Year,24-Hour Storni Event Precipitation(in) 1 80 1 80 1 80 1 80 1 80 1 80 1 80 1 80 1 80 1 80 Runoff Volume(ac-ft) 16 82 5 19 1 51 0 85 0.33 3.20 3 50 2 67 5 99 7 27 Pnnapal Spi Tway Peak Discharge(cfs) 5 30 1 36 1 40 0 58 0 45 1 46 1 65 4 22 2 29 2 44 Emergency Spillway Peak Discharge(ds) 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 0 00 0 00 Peak Surface.Water Stage Elevation(ft) 6588 18 7155 17 6390 15 6326 94 6351 93 6747 01 6831 71 7754 15 6951 03 6952 40 25-Year,24-I-bur Storm Event Precipitation(in) 2 30 2 30 2 30 2 30 2 30 2 30 2 30 2 30 2 30 2 30 Runoff Volume(ac-ft) 27 75 8.51 2 34 1 31 0 51 8 29 6 47 5 15 12 83 18 48 Combined P('ncipal and Emergency Spillway Peak Discharge(cfs) 650 1.88 1 53 0 72 0 62 4 00 2 38 24 69 11 41 81 57 Peak Surface Water Stage Elevation(ft) 6588 00 7156 04 6390 94 6327 91 6352 19 6751 43 6833 57 7755 00 6954 56 6954 69 Pond Freeboard(ft) 3 00 396 9 96 6 09 2 81 3 57 7 43 1.00 1 44 1 31 SEDIMENT LOADING PARAMETERS: Storm Predicted Peak Settlable Concentration(m1/1) 0 00 0 00 0 00 0 00 0 00 0 00 0 00 000 0 00 0 00 SEDCAD estimated Annual Sediment Loading(ac-ft) 0 34 0 12 0 04 0 01 0 02 1 91 0 49 0.06 0 21 0 020 Available Sediment Storage Volume at max sediment storage El(ac-ft) 084 4.86 1 17 0 20 1 03 1 41 2 18 056 0 43 0 43 Maximum sed ment storage elevation (ft) 6581 3 7150 7 6388 3 6323 9 6351 5 6741 6 6825 4 7743.70 6935 00 6935 00 , Predicted Number of Storage Years to Gate Valve Invert 2 5 40 2 26 6 28 4 45 0 1 4 4 4 8.7 2 0 21 8 Revision Date 12/20/19 Exhibit 7 Page 10 Revision No TR-135