HYDRO20108

• Permit No: C1982057
• IBM Index Class Name: Hydrology
• Doc Date: 1/30/1998
• Doc Name: QUARTERLY SEDIMENTATION POND INSPECTIONS SENECA II-W MINE
• From: SENECA COAL CO
• To: DMG
• Permit Index Doc Type: SEDIMENT POND INSPECTIONS
• Media Type: D
• Archive: No

PERIODIC INSPECTION FORM
Water, Sediment, or Slurry Impoundments
INSPECTOR'S NAME: Michael Altavilla DATE: 12/22/97
NPDES I.D. NO.: - CO-0000221 D.P. 006
FACILITY CONFIGURATION: Cross-Valley Pond DATE LAST INSPECTION: 09/26/97
SITE NAME: Pond #006 LOCATION: NWk NWk Sec. 22 TSN R88W
MINE NAME: ~ n a it-W M9n (Seneca Coal Col LOCATION: B mi. S of Hayden, CO
MINE I.D. NO.: CMT.Rn P mi No. -8 -057 OWNER'S REP.: Brad Brown, Gen Mgr
1. Foundation preparation (removal of vegetation, stumps, topsoil: e® No N/A
2. Lift thickness: ~_ in. N/A
3. Compaction according to approved plan: es No N/A
4. Burning (specify extent and location): Yee No
5. Angle of elope: 3:1 upstream, 3:1 downstream Total = 6:1 N/A
6. *Seepage (specify location, color, and approximate volume)
From underdrain pipes: Yes No N/A
At isolated points on embankment slopes: Yes o N/A
At natural hillside: Yes N/A
Over widespread areas: Yes o N/A
From downstream foundation area: Yes N/A
"Boils" beneath stream or ponded water: Yes o
~ N/A
7. Cracks or scarps on crest: Yee o N/A
8. Cracks or scarps on slope: Yes ~ N/A
9. Sloughing or bulging on slope: Yes ~ N/A
10. *Major erosion problems: Yes No N/A
11. Surface movements in valley bottom or on hillside: Yea ~ N/A
12. *Erosion of toe: Yea No N/A
13. *water impounded against toe: Yee ~ N/A
14. Existing embankment freeboard: Annroximately 11.1 feet
15. Increase ~ Decrease in water level: 3.3 feet
16. Cracks, bulging, or erosion on upstream face: Yes ©o N/A
17. Visible aumpa or sinkholes in Blurry surface: Yee No ®A
18. *Clogging
Spillway channels and pipes: Yee No N/A
Decant system: Yes No
D ivereion ditches: Yea No
19. *Cracking or crushing of pipes
Spillway pipes: Yee ~ N A
Decant system: Yes No N/A
20. Trash racks clear and in place: Yes No
*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 apace on
the back of this sheet.