APPCOR13332

• Permit No: C1981034
• IBM Index Class Name: Application Correspondence
• Doc Date: 10/17/1983
• Doc Name: GRAND MESA COAL COS REFUSE DISPOSAL AREA INSPECTION REPORT RECEIVED 10/3/1983
• From: MLRD
• To: DAN MATHEWS
• Media Type: D
• Archive: No

Richartl D. Lamm
Governor
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999
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DEPARTMENT OF NATURAL RESOURCES
Davitl H. Gelches, Executive Director
MINED LAND RECLAMATION DI1
DAVID C. SHELTON, Director
October 17, 1983
T0: Dan Mathews
FROM: Jinn Pendleton
RE: Grand Mesa Com y's Refuse Disposal Area Inspection Report,
Received tobe 1983
Pursuant to your request, I have reviewed the inspection report submitted by
Grand Mesa Coal Company on October 3, 1983. This report presents the results
of the company's staff inspection, including compaction testing of the
underyround development waste pile at the Red Canyon coal mine.
No evidence of structural deterioration was noted during the inspection of the
underground development waste pile. However, the compaction tests performed
on the pile deternined that compaction of the pile failed to achieve the
desired 90% relative compaction level listed on the company's inspection
report farm.
Underground development waste piles are subject to the standard specifications
of Rule 4.09. Rule 4.09 requires that the waste be compacted to that degree
necessary to achieve slope stability. The operator accomplished a stability
analysis of the pile during the completion of permanent program permitting for
the Red Canyon mine. In completing that stability analysis, however, the
company's consultant, Rocky Mountain Geotechnical, Inc., committed to the
submission of final waste material analyses upon their completion.
In my review of the Red Canyon permit document files, I have been unable to
determine whether the promised final waste material mechanical analyses were
submitted. In order to determine what degree of relative compaction is
necessary in order to achieve compliance with the Regulations, it will be
necessary to obtain the final material testing results for the underground
development waste material. I recommend that we request the submission of
complete waste material test results and a statement of the required degree of
compaction consistent with the original design requirements. Preferably, this
submission should be prepared by Rocky Mountain Geotechnical, Inc., who
performed the amended stability analysis. Upon receipt of this additional
information, I will be able to complete an opinion regarding the adequacy of
the reported degree of compaction achieved at the site.
/ant
cc: Brian Munson
DGC. No. 6290
423 Centennial Building, 1313 Sherman Street Denver, Colorado 80203 Tel. [phone]
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