2014-02-07_REVISION - M1979094HR ‎(5)‎

• Permit No: M1979094HR
• IBM Index Class Name: REVISION
• Doc Date: 2/7/2014
• Doc Name: Revised DDP
• From: Whetstone Associates
• To: DRMS
• Type & Sequence: AM1
• Email Name: TC1
• Email Name: DMC
• Media Type: D
• Archive: No

JD -7 Mine - Drainage Design Plan
Table 9. Runoff Curve Numbers for JD -7 Mine ........................................................... ...............................
19
Table 10.
Sub - Basins Contributing Non - Contact Stormwater to Diversion Structures and to the Valley
Floor............................................................................................................. ...............................
22
Table 11.
Sub - Basins Within the JD -7 Mine Permit Area ............................................ ...............................
25
Table 12.
Downstream Receiving Sub - Basins .............................................................. ...............................
31
Table 13.
Reach Geometry and Hydraulic Parameters .................................................. ...............................
33
Table 14.
Stage- Storage Data for Expanded Pit Pool Stormwater Retention Pond ...... ...............................
37
Table 15.
Existing Stormwater Retention Ponds ........................................................... ...............................
38
Table 16.
Stage- Storage Data for Existing Stormwater Retention Ponds 001B -A South and 001B -A North38
Table 17.
Stage, Area, and Storage for Expanded Stormwater Catchment 001B -A North ..........................
40
Table 18.
Stage, Area, and Storage for Expanded Stormwater Catchment 001B -A South ..........................
40
Table 19.
List of Runoff Model Runs - Current Condition .......................................... ...............................
43
Table 20.
Sub -Basin Areas, Receiving Reach, Weighted Average Curve Number, and Time of
Concentration in TR55 Models .................................................................... ...............................
47
Table 21.
Peak Flow (cfs) and Peak Time (hr) by Rainfall Return Period (Current Condition) ..................
49
Table 22.
Comparison of TR -55 Model and Regression Analysis Results for Peak Flow ...........................
53
Table 23.
Conveyance Capacity for Diversion Structures ............................................. ...............................
53
Table 24.
Channel Stage to Convey 100 -year Peak Flow ............................................. ...............................
54
Table 25.
Channel Stage, Velocity, and Shear Stress for 100 -year Peak Flow ............. ...............................
56
Table 26.
Culvert Capacity for 100 -year 24 -hour Storm Event .................................... ...............................
61
Table 27.
Sub - Basins Contributing Non - Contact Stormwater to Diversion Structures and to the Valley
Floor Based on Planned Condition ............................................................... ...............................
65
Table 28.
Sub - Basins Within the Reclaimed JD -7 Mine Permit Area Based on Planned Condition...........
66
Table 29.
Planned Surface Water Control Structures .................................................... ...............................
66
Table 30.
Reach Geometry and Hydraulic Parameters - Planned ................................. ...............................
67
Table 31.
Stage- Storage Data for the Planned Stormwater Catchment Northwest (SCN) Pond ..................
71
Table 32.
Stage- Storage Data for USP DP- 12 ............................................................... ...............................
73
Table 33.
List of Runoff Model Runs for Planned Runoff Routing .............................. ...............................
74
Table 34.
Sub -Basin Areas, Receiving Reach, Weighted Average Curve Number, and Time of
Concentration in TR55 Models (Planned) ................................................... ...............................
74
Table 35.
Peak Flow (cfs) and Peak Time (hr) by Rainfall Return Period (Planned) ... ...............................
77
Table 36.
Conveyance Capacity for Planned Diversion Structures ............................... ...............................
82
Table 37.
Channel Stage to Convey 100 -year Peak Flow in Planned Diversion Structures ........................
83
Table 38.
Channel Stage, Velocity, and Shear Stress for 100 -year Peak Flow in the PDEP and PDWP
Diversion Ditches (Planned) ........................................................................ ...............................
84
Table 39.
Channel Stage and Velocity for 10 -Year and 100 -year Peak Flow in the OPWRDP and NDP
DiversionDitches (Planned) ........................................................................ ...............................
86
LIST OF FIGURES
Figure 1. Photo Showing Dry Drainage and Sandy Streambed in Major Sub -Basin B2 ............................... 2
Figure 2. Photo Facing Downstream (North) Showing Drainage Characteristics on Valley Floor in Sub -
Basin B2, South of JD -7 Topsoil Stockpile ................................................... ............................... 3
Figure 3. Minor Sub - Basins Modeled Within Major Sub -Basin B3 (Current Condition) ............................. 5
Figure 4. Location of Sheet Flow, Shallow Concentrated Flow, and Channel Flow within a Basin ............. 7
Figure 5. Soil Types in Vicinity of JD -7 Mine .............................................................. ............................... 20
Figure 6. Spatial Distribution of Curve Numbers across the JD -7 Mine Area (Current) ............................. 21
Figure 7. Photograph Showing Pit Diversion West ....................................................... ............................... 23
Figure 8. Aerial Photograph showing Alluvial Fan and Braided Ephemeral Channels on Valley Floor near
Sub - Basins N -J and N- K .............................................................................. ............................... 24
4149A.140207 Whetstone Associates