2010-12-22_HYDROLOGY - C1982057 ‎(2)‎

• Permit No: C1982057
• IBM Index Class Name: HYDROLOGY
• Doc Date: 12/22/2010
• Doc Name: 4th Quarter 2010 Sedimentation Pond Inspections
• From: Seneca Coal Company
• To: DRMS
• Permit Index Doc Type: Sediment Pond Inspect
• Email Name: SB1
• Email Name: SLB
• Media Type: D
• Archive: No

PERIODIC INSPECTION FORM
Water, Sediment, or Slurry Impoundments
INSPECTORS NAME: _ Dennis Jones
NPDES I.D. NO.: CO-0000221 D.P. 006
FACILITY CONFIGURATION: Cross-Valley Pond
SITE NAME: Pond 4006
MINE NAME: Seneca II-W Mine (Seneca Coal Cc)
MINE I.D. NO.: CMLRD Permit No. C-82-057
DATE: lo-111-10-
DATE LAST INSPECTION: 9-2,- ( V
LOCATION: NWY. NWl/, Sec. 22, TSN, R88W
LOCATION: 8 mi. S of Hayden, CO
OWNERS REP.: Roy Karo, Gen Mgr
Circle or write in appropriate response
1. Foundation preparation (removal of vegetation, stumps, topsoil: Yes
2. Lift thickness: 12 in.
3. Compaction according to approved plan: Yes
4. Burning (specify extent and location): No
5. Angle of slope:: 3:1 upstream, 3:1 downstream Total = 6:1
6. *Seepage (specify location, color, and approximate volume)
From underdrain pipes: N/A
At isolated points on embankment slopes: Yes No N/A
At natural hillside: Yes No N/A
Over widespread areas: Yes No N/A
From downstream foundation area: Yes No N/A
"Boils" beneath stream or ponded water: Yes No N/A
7. Cracks or scarps on crest: Yes No N/A
8. Cracks or scarps on slope: Yes No N/A
9. Sloughing or bulging on slope: Yes No N/A
10. *Major erosion problems: Yes No N/A
11. Surface movements in valley bottom or on hillside: Yes No N/A
12. *Erosion of toe:: Yes No N/A
13. *Water impounded against toe: Yes N N/A
14. Existing embankment freeboard: (normal = 7.51) -j..5 feet
15. Increase: Decrease in water level: V.o ei?c..1 feet
16. Cracks, bulging, or erosion on upstream face: Yes N/A
17. Visible sumps or sinkholes in slurry surface: N/A
18. *Clogging
Spillway channels and pipes: Yes N/A
Decant system: N/A
Diversion ditches: Yes N/A
19. *Cracking or crushing of pipes
Spillway pipes: Yes ® N/A
Decant system: N/A
20. Trash racks clear and in place: es No N/A
21. Discharge rate (gpm) -31
*Major adverse changes in these items could cause instability and should be reported to the
Engineering Manager and Mine Superintendent for further evaluation. Adverse conditions noted in
these items should normally be described (extent, location, volume, etc.) in the space on the
back of this sheet.