2009-01-14_REPORT - C1981022

• Permit No: C1981022
• IBM Index Class Name: REPORT
• Doc Date: 1/14/2009
• Doc Name: 4th Quarter 2008 Wastepile Report
• From: Oxbow Mining, LLC
• To: DRMS
• Permit Index Doc Type: Waste Pile/Fill Report
• Email Name: MLT
• Media Type: D
• Archive: No

W MINING, LL C
FOURTH QUARTER 2008
ENGINEERING INSPECTION
EAST YARD, WEST VALLEY FILL AND II WEST
COAL MINE WASTE DISPOSAL PILES

The approved Oxbow Mining, LLC (OMLLC) Mine permit includes a requirement for quarterly inspections of
coal mine waste piles for stability. The inspection is to be performed by a registered engineer or other qualified
professional specialist, who is experienced in the construction of earth and rockfill embankments. On
December 30, 2008 visual inspections were performed of the East Yard, West Valley Fill and H West coal mine
waste disposal areas. A total of 6 successful compaction tests were performed on 11-19-08 and 10-02-08 and
are included herein for the Division's information. All areas were covered by 1.5 feet of snow.
EAST YARD - The East Yard disposal area has reached its design capacity, and no new waste material has
been placed since June of 2001. The revegetated slope was inspected for signs of erosion or instability and
vegetation establishment. No erosional features were noted requiring repairs to revegetated areas. The covering
of the waste pile is considered complete. Nothing was observed during the inspection that would indicate the
pile has a potential for structural failure.
WEST VALLEY FILL - During the third quarter, no waste was hauled to or from the West Valley Fill area.
The elevation of the waste pile was unchanged and surveyed at the approximate 6226' elevation.
The revegetated outslope located between the fill slope toe to the approximate 6200' elevation was inspected
for signs of erosion and instability. No erosional features were noted requiring repairs to any vegetated areas.
The third bench (approximate 6200' elevation) setback remains established for the final lift of waste material
and the ramp constructed on the waste pile to provide access to the H West Coal Refuse Facility light use road
and haul road. These two roads continue to be utilized. No springs or seeps were noted. Surface drainage
control features are performing according to the plan. Nothing was observed during the inspection that would
indicate the West Valley Fill has a potential for structural failure.
II WEST - The II West disposal area received approximately 290 cy of additional coal mine waste material
during the fourth quarter of 2008. The elevation of waste material is at the approximate 6090' elevation. The in
place material has been worked to meet moisture and compaction requirements. No springs or seeps were
noted. Surface drainage control features are performing according to the plan. The grading and drainage of the
first bench was improved and completed. The seeding of the face of the fill to 20' above the first bench was
competed on November 26, 2008 using the approved seed mix. Nothing was observed during the inspection-
that would indicate the 11 West Fill has a potential for structural failure.
,A? ?- k( I -A--? --
Inspected by Jame . Kiger
Q ZOO'?
Thomas C. Anderson Date
Colorado Licensed Professional Engineer No. 14726
3737 Hwy 133 • P.O. Box 535 • Somerset, Colorado 81434 USA
TEL [phone] • FAX [phone]