2009-08-17_REVISION - C1996083

• Permit No: C1996083
• IBM Index Class Name: REVISION
• Doc Date: 8/17/2009
• Doc Name: Request for Assistance
• From: Joe Dudash
• To: Marcia Talvitie
• Type & Sequence: TR64
• Email Name: MLT
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
DATE: August 17, 2009
TO: Marcia Talvitie
COLORADO
D I V I S I ON OF
RECLAMATION
MINING
SAFETY
Bill Ritter, Jr.
Governor
Harris D. Sherman
Executive Director
Ronald
FROM: Joe Dudash W. Caft
Division Director
or
Natural Resource Trustee
RE: Bowie No. 2 ?e, ermit No. C-1996-083, Bowie Resources LLC
Technical Revision No. 64, Increase Height of Coal Waste Pile No. 4, Request for
Assistance
I am requesting your assistance in the review of the geotechnical aspects of Technical Revision No. 64 (TR-
64) for the Bowie No. 2 Mine. In TR-64, Bowie Resources LLC (BRL) is revising the approved plan for
coal waste storage at coal waste pile no. 4.
The currently approved plan for coal waste pile no. 4 is based on a Buckhorn Geotech study from TR-44,
found in Volume IX and dated February 1, 2007. This report showed that coal waste pile no. 4, with a
height of 118 feet, a lower bench outslope of 2.5H:1 V and the upper bench outslopes of 3H:1 V, has a factor
of safety of 1.5 or greater. In TR-64, BRL is proposing a new height of about 150 feet for coal waste pile
no. 4 but with the currently approved outslope gradients. A geotechnical report was submitted with TR-64
to show that the factor of safety is still at least 1.5. The proposed increase in height of coal waste pile no. 4
appears to be due to the base of the pile being lower and the top of the pile being higher than had been
approved previously.
A revised surface water drainage configuration and redesigns of drainage structures associated with coal
waste pile no. 4 are also included in TR-64. However, I will review these surface water hydrology designs.
TR-64 was called complete on August 14, 2009. Therefore, the Division's adequacy review letter is due
Monday, September 14, 2009. 1 would appreciate your adequacy review memo back by Thursday,
September 10. Please let me know if you need additional review time.
Attached is one complete copy of TR-64. If you have any questions or need additional information, please
let me know. Thanks for your assistance!
Attachments
cc: Sandy Brown (without attachments)
c:/word2007/bowie2/tr64memo 1
Office of Office of
Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines