2013-10-30_REVISION - M1977310 ‎(3)‎

• Permit No: M1977310
• IBM Index Class Name: REVISION
• Doc Date: 10/30/2013
• Doc Name: DRAINAGE DESIGN PLAN FOR THE JD6 MINE
• From: COTTER
• To: DRMS
• Type & Sequence: AM1
• Email Name: TC1
• Email Name: SJM
• Media Type: D
• Archive: No

JD -6 Mine - Drainage Design Plan
6.1 Summary of Existing Structural Controls for Stormwater ...................... .............................43
6.2 Sediment and Erosion Prevention ........................................................... .............................43
6.3 Post - Mining Stormwater Controls .......................................................... .............................44
7. REFERENCES ........................................................................................................... .............................45
LIST OF TABLES
Table 1. Major Sub -Basin Areas at the JD -6 Mine ........................................................... ..............................1
Table 2. Design Storm Parameters .................................................................................... ..............................2
Table 3. Manning's "n" Values Used in Cowan's Method for Channel Roughness ........ ..............................6
Table 4. Soils Types in Vicinity of the JD -6 Mine Facilities (Sub -Basin 132) ................. .............................10
Photograph of Waste Rock Piles and Mine Facilities Area .............................. .............................16
Table 5. Runoff Curve Numbers for Arid and Semi -Arid Rangelands .......................... ...............................
l l
Table 6. Runoff Curve Numbers for JD -6 Mine ............................................................ ...............................
l 1
Table 7. Sub - Basins Contributing to Upper, Middle, and Lower Diversion Structures .. .............................12
Typical Channel Profiles Measured in Upper Diversion Structure ( UDS) ....... .............................19
Table 8. Sub -Basin Intercepted by EE 19 Road ................................................................ .............................12
Figure 6.
Table 9. Sub -Basins Contributing Run -On to Mine Facilities Area ................................ .............................14
Table 10. Reach Geometry and Hydraulic Parameters .................................................... .............................18
Typical Channel Profiles Measured in Middle Diversion Structure ................. .............................21
Table 11. Upper Diversion Structure Channel Geometry ................................................ .............................18
Figure 8.
Table 12. Middle Diversion Structure Channel Geometry .............................................. .............................21
Table 13. Lower Diversion Structure Channel Geometry ............................................... .............................22
Photograph of Lower Diversion Structure North (LDS -N) .............................. .............................23
Table 14. Structure Parameters ...................................................................................... ...............................
25
Table 15. Stage- Storage Data for the Planned Stormwater Retention Pond .................... .............................26
Table 16. Sub -Basin Areas, Receiving Reach, Weighted Average Curve Number, and Time of
Concentrationin TR -55 Model ....................................................................... .............................30
Table 17. Peak Flow (cfs) and Peak Time (hr) by Rainfall Return Period ...................... .............................34
Table 18. Conveyance Capacity for Diversion Structures ............................................... .............................35
Table 19. Channel Stage to Convey 100 -year Peak Flow ................................................ .............................36
Table 20. Channel Stage, Velocity, and Shear Stress for 100 -year Peak Flow for the MDS, LDS -E, and
LDS -N ............................................................................................................ .............................36
Table 21. Stage, Velocity, and Shear Stress for 100 -year Peak Flow for the Existing and Planned UDS ...38
Table 22. Required S WRP Capacity to Contain the 10 -year 24 -hour Storm ................... .............................39
Table 23. Calculated Runoff Reporting to the S WRP from the 100 -year 24 -hour Storm ............................40
Table 24. Planned Retention Pond Spillway Analysis ..................................................... .............................42
Table 25. Culvert Capacity for 100 -year 24 -hour Storm Event ....................................... .............................43
LIST OF FIGURES
Figure 1. Site Map Showing Sub -Basins Contributing to Upper, Middle, and Lower Diversion Structures 13
Figure 2.
Site Map Showing Sub - Basins Contributing to Mine Facilities Area .............. .............................15
Figure 3.
Photograph of Waste Rock Piles and Mine Facilities Area .............................. .............................16
Figure 4.
Detailed Site Map Showing Stormwater Flow Directions in the Mine Facilities Area .................17
Figure 5.
Typical Channel Profiles Measured in Upper Diversion Structure ( UDS) ....... .............................19
Figure 6.
Photographs of Upper Diversion Structure ....................................................... .............................20
Figure 7.
Typical Channel Profiles Measured in Middle Diversion Structure ................. .............................21
Figure 8.
Photograph of Lower Diversion Structure East ( LDS- E) ................................. .............................23
Figure 9.
Photograph of Lower Diversion Structure North (LDS -N) .............................. .............................23
Figure 10.
Photograph of Lower Diversion Structure North (LDS -N) ............................ .............................24
4148A.131028 Whetstone Associates •