2009-02-09_REPORT - C1981010

• Permit No: C1981010
• IBM Index Class Name: Report
• Doc Date: 2/9/2009
• Doc Name: Review of Semi-Annual Geotechnical Monitoring Report ‎(Sept-2008)‎ Memo
• From: Marcia Talvitie
• To: Jason Musick
• Permit Index Doc Type: Stability Report
• Email Name: JDM
• 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:
To:
From:
Subject:

Bill Ritter, Jr.
Governor
INTEROFFICE MEMORANDUM Harris D. Sherman
Executive Director
Ronald W. Cattany
Division Director
02 February 2009 Natural Resource Trustee
Jason D. Musick
Marcia L. Talvitie, P.E.ltl?itoOi??t??
Trapper Mining, Inc. - Permit No. C-1981-010
Review of Semi-Annual Geotechnical Monitoring Report (Sep-2008)
At the request of Dan Hernandez (made via Email on 24-Dec-2008), I have conducted a
review of the above-described Geotechnical Monitoring Report ("GMR") for the Trapper
Mine. Per the commitments made in TR-99 (Permit Section 3.3.3, pp 3-27a thru 3-27d),
Trapper Mining, Inc. (TMI) will submit a monitoring results to the Division on a semi-
annual basis in March and September.
The September 2008 GMR expands upon the data presented in the March 2008 version,
and includes inclinometer, piezometer and benchmark data collected from April through
September 2008. Based upon the results to date, TMI's geotechnical consultant, Agapito
& Associates, Inc. (AAI) recommends reducing the data collection frequency. The
following table provides a comparison between the Approved and Recommended
monitoring frequencies for the G-Pit Slide Area.
Approved Monitoring New Frequency Recommended by AAI
Frequency
Inclinometers /Piezometers / Inclinometer / Piezometers
Benchmarks Benchmarks
Once per month during dry Once per month during dry season (No Change)
season
Once per week April-May Once per week for two Once per week for two
and September-October k
f
ll
i k
f
ll
i
ng a major
wee
s
o
ow wee
s
o
ow
ng a major
Once per day after rainstorm rainstorm event (>0.5 inch) rainstorm event (>0.5 inch)
events >0.50 inches for 3-4 or major snow melt (loss of or major snow melt (loss of
days transi weekly cover >2 inches) cover >2 inches)
for 1 1-2 2 weeks
COLORADO
DIVISION O F
RECLAMATION
MINING
SAFETY
Office of Office of
Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines