2001-12-11_PERMIT FILE - C1996084

• Permit No: C1996084
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: EXHIBIT 15-26 MINE AREA P7 SEDIMENT CONTROL POND 7-4
• Media Type: D
• Archive: No

SEDCAD 4 for Windows
Co01^ight 1999 Pamela J Schwab
CrvJ Software Design
w/o Freeboard w/ Freeboard
• Froude Number: 1.98
Structure #3 (Pond1
n, coal, slope
Pond Inputs:
Initial Pool Elev: 6,636.00
Initial Pool: 1.34 ac-ft
'Sediment Storage: 1.54 ac-ft
Dead Space: 20.00
#Sediment capacity based on Average Annual R of 70.0 for 2 year(s)
Perforated Riser
Riser Riser Height Barrel Barrel Barrel Slope Number of
'
Diameter (ft) Diameter Length (ft) (%) Manning
s n Spillway Elev Holes per
(in) (in) Elev
12.00 6.00 8.00 80.00 3.00 0.0240 6,638.00 4
Emergency Spillway
• Spillway Elev Crest Length Lek Right Bottom
(ft) Sideslope Sideslope Width (ft)
6,640.00 10.00 2.50:1 2.50:1 2.00
Pond Results:
Peak Elevation: 6,639.11
H'graph De[ention Time: 8.28 hrs
Pond Model: CSTRS
Dewa[er Time: 6.09 days
Trap Efficiency: 90.73
Dewatering time is calculated from peak stage to lowest spillway
Elevation-Capacity-Discharge Table
•
Area Capacity Discharge Dewater
Elevation Time
(ac) (ac'ft) (ds) (h5)
6,633.66 0.508 0.000 0.000 Top of Sed. Storage
6,634.00 0.526 0.177 0.000
6,634.50 0.552 0.447 0.000
6,635.00 0.578 0.729 0.000
Filename: 100pond7-4.sc4 Printed 04-24-2001