REP16852

• Permit No: C1981019
• IBM Index Class Name: Report
• Doc Date: 6/3/2005
• Doc Name: 2nd Qtr 2005 West Pit Fill Inspection Report & Certification
• From: Knight Piesold and Co
• To: DMG
• Permit Index Doc Type: Waste Pile/Fill Report
• Media Type: D
• Archive: No

Knight Piesold
CONSULT 1 N G
June 3, 2005
For: File
Knight Piesold and Co.
1050 Seventeenth Street, Suite 450
Denver, Colorado 80265-2011
U.S.A.
Re: Colowyo Coal Company L.P. (C-81-019) Telepfeone [phone]
West Pit Fill Inspection Report and Certification Te[efax [phone]
SeCOnd Qnarter, 2005 VOUR REFERENCE
OUR REFERENCE
West Pit Fill Inspection Certification
On May 25, 2005, I inspected the azea in which the West Pit Excess Spoil Fill is being constructed.
The purpose of this inspection was to observe the surface rock drain that borders the 3:1 Excess Fill
Slope; inspect the areas dumped to final grade below the 7,400 dump elevation; inspect the
revegetation on the fill surface; inspect the fill for areas of water seepage or surface drainage;
inspect the final grade slopes below the 7,300 elevation of the Excess Fill Slope; and satisfy the
requirements of CDMG Rule 4.09.1(1 la) and Rule 4.09.1 (1lb).
During the inspection, it was observed that the condition of the fill was good and that no seeps or
springs were noted. The collection ditches at the 6,950, 7,050, and 7,150 elevations all were in
relatively good shape. The ditch at the 7,250 elevation needs to be completed to the west end of the
fill. No water was evident in the surface drain or underdrains.
In addition, I reviewed the monument survey data. These data indicate that the elevations of most
of the monuments have not significantly changed (less than 0.1 feet of movement) with the most
movement noted in the 7,250 east and 7,250 west monuments (0.07 feet each), and in the 7150 east,
the 7150 mid, and 7150 west monuments (0.06 feet, 0.07 feet, 0.08 feet, respectively). There was
also no evidence of structural weakness or other hazardous conditions associated with this dump.
These monument survey data are available for review upon request at the Colowyo Mine site.
I am a Licensed Professional Engineer in the State of Colorado and a representative of Knight
Piesold and Co., 1050 Seventeenth Street, Suite 450, Denver, Colorado 80265-2011. Being familiar
with the Colowyo operation and the coal program permitting process in Colorado, the construction
activities related to the West Pit Excess Spoil Fill are in conformance, to the best of my knowledge
and experience, as specified in pages la-2 through la-4, Exhibit 191b and other applicable
requirements of the approved permit documents, a portion of CDMG Permit C-81-019. '
Colorado
S
xc: Mr. Crellin Scott, Colowyo Coal Company, L.P.
cf 17.15.1 2004