2009-03-02_PERMIT FILE - C1980004 ‎(15)‎

• Permit No: C1980004A
• IBM Index Class Name: Permit File
• Doc Date: 3/2/2009
• Section_Exhibit Name: Appendix M Hydrologic Calculations
• Media Type: D
• Archive: Yes

APPENDIX M
McCLANE CANYON MINE
PROTECTION OF THE HYDROLOGIC BALANCE
STORM EVENTS
10 YEAR 24 HOUR EVENT 1.7 INCHES
25 YEAR 24 HOUR EVENT 2.1 INCHES
100 YEAR 24 HOUR EVENT 2.4 INCHES
The information presented for peak flow calculations is developed with the use of
SEDCAD. The output from SEDCAD follows is summarized on the ditch design sheets.
The run-off areas are shown on Figure 2.2-3. The run-off
curve numbers are developed based upon vegetation and soil
types. Vegetation data is presented on Table 4.5-26 and shown on
Figure 4.5-1. Soils data are presented in on page 4-35 and shown on
Figure 2.2-2.
Disturbed
Table 2-2c-Runoff curve numbers for other agricultural lands
Cover Type -Desert Shrub -major plants include saltbush, greasewood,
creosotebush, blackbrush, bursage, palo verde, mesquite and cactus.
Hydrologic Condition Poor
} Soil Type -Loam p
- Curve Number gg
Shadscale Shrubland
Cover
Vegetative Cover % 62.7
Litter % 10.0
Ground Cover % 72.7
Table 2-2c-Runoff curve numbers for other agricultural lands
Cover Type -Desert Shrub -major plants include saltbush, greasewood,
creosotebush, blackbrush, bursage, palo verde, mesquite and cactus.
Hydrologic Condition Fair
Soil Type -Loam C
Curve Number 81
TR-16 13 05/08