REP09207

• Permit No: C1996083
• IBM Index Class Name: Report
• Doc Date: 8/20/1998
• Doc Name: BOWIE 2 MINE COAL WASTE PILE COMPACTION REPORTS FIRST AND SECOND QUARTERS OF 1998
• From: DMG
• To: JOE DUDASH
• Permit Index Doc Type: STABILITY REPORT
• Media Type: D
• Archive: No

iii iiiiiiiiiiiii iii
999
STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Depanmenl of Natural Resources
1 313 Sherman 51., Room 215
Denver, Colorado 80'03
Phone: [phone]
FAX: [phone]
DATE: August 20, 1998
TO: Joe Dudash

II~
DEPARTMEfYT OF
NATURAL
RESOURCES
Rny Ramer
Governor
lames S Lochhead
FROM• Jim Pendleton ~ Execwive Duecior
• Michael B Lung
Divaion Director
RE: Bowie #2 the - Co aste Pile Compaction Reports -First and Second
Quarters o (Permit No: C-96-083)
I have reviewed the materials concerning compaction control at the Bowie #2 Coal Mine Waste
Pile, which you forwarded to my attention. These materials included your letter to the operator
dated March 4, 1998, several responses from the operators consultant conceming underdrain
construction, and the quarterly waste pile inspection reports prepared by the operator's
consultant, dated April 24, 1998 and July l6, 1998. I have several concerns which require
resolution.
Issues in Dudash Letter, dated March 4, 1948
As you mentioned within your letter, we had discussed your concerns prior to the issuance of
your letter. I am, therefore, aware of, and in agreement with, your concerns expressed in the
letter. Five specific issues were addressed in your letter.
Source of the higher than anticipated moisture contained in [he coal waste?. - No
response is presented to your inquiry.
2. Are the original Mechanical Strength Analyses and Proctor.9nalyses representative of
[he amended coal waste? - If the actual properties are weaker than those used in
completing the original stability analysis, the waste pile may not meet stability
requirements of the regulations. A second Proctor analysis was apparently perforned,
because a significantly different standard is referenced in the second quarterly report.
However, no comprehensive response has been provided to your statement of concern, as
you requested. Further, I am concerned that neither of the proctor standards referenced
within the two quarterly reports may be representative of the specific amended waste
materials being inspected.
The April 24, 1998 (First Quarter `98) waste pile inspection report presents the results of
eleven compaction tests performed on the pile. Five of these eleven tests determined
relative densities to exceed 1 l0%, ranging between 1 10.3% and 117% of the optimum