2008-07-25_REPORT - C1981010

• Permit No: C1981010
• IBM Index Class Name: REPORT
• Doc Date: 7/25/2008
• Doc Name: Review of Semi-Annual Geotechnical Monitoring Report Memo
• From: Marcia Talvitie
• To: Jason Musick
• Permit Index Doc Type: Stability Report
• Email Name: MLT
• Media Type: D
• Archive: No

STATE OF COLD
DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
Date:
To:
From:
Subject:
Dear Jason:
COLOI,RADO
D I V I S I ON OF
RECLAMATION
MINING
SAFETY
INTEROFFICE MEMORANDUM
Bill Ritter, Jr.
Governor
25 July 2008 Harris D. Sherman
y Executive Director
Ronald W. Cattany
Jason Musick Division Director
Natural Resource Trustee
Marcia L. Talvitie??y
Trapper Mining, Inc. - Permit No. C-1980-010
Review of Semi-Annual Geotechnical Monitoring Report (Mar-2008)
At your request, I have conducted a review of the above-described Geotechnical
Monitoring Report ("GMR") for the Trapper Mine, received by the Division on 27-Mar-
2008. The Report is to be submitted semi-annually, per the requirements of Technical
Revision No. 99 (TR-99) to Permit No. C-1980-010, incorporated into Section 3.3.3 of
the application as pages 3-27a, 3-27b, 3-27c and 3-27d.
1) There is a discrepancy within the permit file pages I retrieved from the Division's
LaserFiche system. The second paragraph of page 3-27a states, "A total of three sites
will be completed with inclinometers, four sites with piezometers..." However, Table
3.3-3, on page 3-27d can be interpreted to indicate that four inclinometers and six
piezometers will be installed. It would appear that at some point during the TR-99
process, it was determined that Boreholes 07-GI5, -GI6, and -GI7 would not have
additional instrumentation installed, but that the second column of Table 3.3-3 was never
updated. I will proceed under the assumption that that is (was) the case.
2) Table 3.3-3 includes proposed lengths (in feet) for the three inclinometers and four
piezometers installed. These lengths differ from those reported in the GMR (some are
longer; some are shorter).
Please provide an explanation of the variations in length of instrumentation between
Table 3.3-3 and the GMR.
3) Piezometer Data - The GMR cover letter (page 2) states that, "Piezometers inside the
slide area tend to have higher psi readings than those outside the slide area." The data
presented for 07-GI3 (inside the slide) are, indeed, higher than the measurements reported
Office of Office of
Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines