PERMFILE61228

• Permit No: C1996084A
• IBM Index Class Name: Permit File
• Doc Date: 7/5/2002
• Section_Exhibit Name: Section 2.05 Operation and Reclamation Plans
• Media Type: D
• Archive: Yes

Rule 2: Pernulr
• Table 2.05.3-1a
Lorencito Canyon Mine
Culvert Sizing for Subwatersheds and Associated Flows
Culvert Pi a Size ~ Subwatershed Area acres Dischar a cfs
18 0 - 14.5 0 - 5.8
21 14.5 - 21.3 5.8 - 8.5
24 21.3 - 29.8 8.5 - 11.8
30 29.8 - 44.4 11.8 - 20.7
36 44.4 - 70.1 20.7 - 32.6
42 70.1 - 103.1 32.6 - 48.0
45 103.1 - 121.5 48.0 - 57.0
48 121.5 - 142.8 57.0 - 67.0
54 142.9 - 191.7 67.0 - 89.9
60 191.7 - 249.5 89.9 - 117.0
66 249.5 - 316.6 117.0 - 148.5
72 316.7 - 393.6 148.5 - 184.6
84 393.6 - 578.6 184.6 - 271.4
96 576.6 - 807.9 271.4 - 379.0
1 - Culverts are sized for no headwater above culvert.
2 - The smallest culvert that will be used for haul roads is 18 inches in diameter regardless of
subwatershed area and discharge.
3 - Based on 10-year, 24-hour, storm event.
contents of ] 0 to 18 percent. For design purposes, a moist unit weight of 125 pcf is considered
• appropriate. Material consisting of lazge-size rock will be placed in uniform layers not exceeding the
average size of particles, lifts not in excess of 36 inches, and placed in a manner to minimize voids,
pockets, and bridging. The sub-base will be strengthened when conditions warrant with geotextiles.
The final layer will meet the requirements described above.
•
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InieicibPm~-PMT(si57Ap2001.wpE 2.05-17a (revised 9/10/01)