REP15867

• Permit No: C1981041
• IBM Index Class Name: Report
• Doc Name: STABILITY ANALYSIS CAMEO REFUSE DISPOSAL AREA 1 POWDERHORN COAL CO CAMEO COLO FEB 1994 ADDENDUM May,
• Permit Index Doc Type: STABILITY REPORT
• Media Type: D
• Archive: No

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Mr. Reschke noted that these conditions were normal.
No visible signs of tension cracks, scarps, slope bulging or
instability were evident during the inspection. As noted above the
2:1 slopes are fairly uniform, some trimming and slope shaping
would be required to bring them (the slopes) to a true 2:1. In
general, the pile as constructed thus far, does not exhibit visible
signs of instability.
Mr. Reschke noted that future plans call for the completion of
refuse placement to elevation 5025, at which time the entire pile
will be covered with 18-inches of native soil.
DATA REVIEW AND EVALUATION:
The following material was provided by Powderhorn Coal, Co.
for review and evaluation with respect to the present stability
analysis:
1. A report prepared by Lincoln DeVore, "Foundation
Investigation, Coal Canyon Waste Pile Site, Cameo,
Colorado", circa April 29, 1980.
2. A report prepared by Rocky Mountain Geotechnical,
"Stability Evaluation, Cameo Mine Refuse Pile, Palisade,
Colorado", circa October 24, 1980.
3. Topographic maps of the site depicting the foundation
surface; the location of foundation drill holes; the
location of underdrains; and the proposed final
configuration of the refuse pile.
4. Field density test results for CRDA No. 1 from February
23, 1991 through September 12, 1986.
5. Piezometer elevation, location and depth coordinates and
a historical record of piezometer measurement readings.
In addition to the material noted above, local climatological
data (from 1980 to the present) was obtained from the Walker Field,
National Weather Service Office. Of particular interest were
precipitation records, which were applied to the piezometer data
evaluation.
The "Foundation Investigation" and "Stability Evaluation"
reports were thoroughly perused and both seem to present accurate,
complete and informative discussions of their respective subjects.
Information from drill logs, regarding the depth and composition of
the alluvium and bedrock foundation materials, were adopted for the
present analysis, from the "Foundation Investigation" report.
Information regarding material strength characteristics found in
the "Stability Evaluation" are incorporated in the present
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