REV03771

• Permit No: C1996083
• IBM Index Class Name: Revision
• Doc Date: 2/27/2003
• Doc Name: Bruce Park Dam Study Review ‎(Memo)‎
• From: Byron Walker
• To: Joe Dudash
• Type & Sequence: TR22
• Media Type: D
• Archive: No

STATE OF COLOlZADO
DIVISION OF MINERALS AND GEOLOGY
Department of Natural Resources -
1313 Sherman SC, Room 215
Denver, Colorado 80203 DIVISION O F
Phone: [phone] lit 1 N E RA L $
FAX: [phone] &
GEOLOGY
RECLAMATION
Interoffice MEMORANDUM MINING•SAFETY
BiII Owens
to: Joe Dudash Governor
from: Byron G. Walker.~w~ Greg E. warner
Executive Director
subject: Adequacy Review, TR-22, Bruce pazk Dam Study, Bowie No. 2 Mine, Permit~[ga w. wnany
C-96-083, Bowie Resources Limited Division Director
date: February 27, 2003
Joe, this memo is in response to your memo, same subject of February 25, 2003
With regard to the Addendum to Geotechnical Report -Bruce Park Dam
Item 1. Yes, the lack of piezometer measurements taken when the reservoir level was at
maximum normal pool is of concern, but to do so may not be practical. If taken at that time, the
readings would be the best way of describing a design piezeometric surface. The calculation of
the factor of safety for the reservoir embankments should consider a piezometric surface as if the
pool were at normal operating level, not the level of piezometer readings when the reservoir was
10 to 15 feet below the normal maximum pool. It is generally assumed.
Item 2. Yes. A new analysis would be required if the dam was raised. If mining is approved first,
safety should be evaluated before such a rising.
With regard to the Geotechnical Evaluation ofMine-Induced Seismicity on Bruce Park Dam
Item 3. Yes, it would be of value to contact NIOSH. Specific data and design procedures would
be better than the best of correlations with other methods.
Item 4. I don't think so. The report itself gives the data. We should be able to agree or disagree
with the statement.
With regard to the General Questions
Item 5. No. The Addendum to Geotechnical Data Report Bruce Park Dam report prepazed by
GEI Consultants, Inc. and submitted by Bowie Resources, Limited, makes no engineering
analysis of mining activity. The Geotechnical Data Report Bruce Pazk Dam by GEI Consultants,
Inc., makes no engineering analysis of mining activity. Such analyses would likely be found in an
engineering design report, not the geotechnical investigation reports. Geotechnical investigations
provide data for engineering reports.