HYDRO27434

• Permit No: C1994082
• IBM Index Class Name: Hydrology
• Doc Date: 11/30/1999
• Doc Name: 3rd Qtr 1999 Sediment Pond Inspections
• 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 Altavil la DATE: D9~22~99
NPDES I.D. NO.: CO-0000221 D.P. 0 11
FACILITY CONFIGURATION: mros~-Va11_Q y Pond DATE LAST INSPECTION: O6 /_3 D/99
SITE NAME: Pend 8011 LOCATION: NF.~ SW11iSec. 76 TSN R87W
MINE NAME: Yoast Mine ($ n ca oar - o) LOCATION: 8.5 mi. SE of Hayden CO
MINE I.D. NO.: rMi.Rn Permit No. C-9 4-082 OWNER'S REP.: Brad Brown Gen Mgr
1. Foundation preparation (removal of vegetation, stumps, topsoil: ee No N/A
2. Lift thickness: _8_ in. N/A
3. Compaction according to approved plan: Yes No N/A
4. Burning (specify extent and location): Yes No y~/_
5. Angle of elope: 3.0:1 upstream, 2.8et downstream Total = 5_,.811 N/A
6. *Seepage (specify location, color, and approximate volume)
From underdrain pipes: Yee N/A
At isolated points on embankment slopes: Yes N/A
At natural hillside: Yea N N/A
Over widespread areas: Yee N/A
From downstream foundation area: Yee o N/A
"Boils" beneath stream or ponded water: Yee o N/A
7. Cracks or scarps on treat: Yes N N/A
8. Cracks or scarps on elope: Yee ~ N/A
9. Sloughing or bulging on elope: Yea ~ N/A
10. *Major erosion problems: Yes ~ N/A
11. Surface movements in valley bottom or on hillside: Yee ~ N/A
12. *Eroaion of toe: Yes ~ N/A
13. *Water impounded against toe: Yea N/A
14. Existing embankment freeboard: Annroximately 16.5 feet
15. Increase _~ Decrease in water level: 1.D feet

16. Cracks, bulging, or erosion on upstream face: Yes
17. Visible sumps or sinkholes in slurry surface: Yea No N/A
18. *Clogging
Spillway channels and pipes: Yes ~ N A
Decant system: Yee No
Diversion ditches: Yee No
19. *Cracking or crushing of pipes
Spillway pipes: Yes ®° N/A
Decant system: Yee No
20. Trash racks clear and in place: Yes No A
*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.