Laserfiche WebLink
T&lPPEB MININD INC@ <br />March 31, 2010 <br />Mr. Jason Musick RECE N' D <br />Environmental Protection Specialist <br />Colorado Division of Reclamation, Mining and Safety APR 0 5 Z0)10 <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 D?w?wn n? <br />iAfning and 5,;J* <br />Dear Mr. Musick: <br />Re: Semi-annual Geotechnical Monitoring Report- March 2010 <br />Trapper has been monitoring assorted benchmarks, inclinometers and piezometers that were installed to <br />evaluate movement in the landslide area as plans were being made for development of this area. <br />Trapper has submitted semi-annual monitoring reports to the Division, beginning in March of 2008 with <br />the last report sent on September 30, 2009. These reports summarized data from a series of <br />inclinometers, piezometers and bench marks that were, generally speaking;, monitored monthly. <br />As part of a revised Ground Control Plan, submitted to and filed by MSHA, development of the slide <br />area and proposed monitoring requirements were addressed. The result was installation of a state-of-the- <br />art continuous monitoring system comprised of four sites with associated inclinometers, piezometers and <br />GPS monitoring stations (see the attached plate that shows the locations). Data is transmitted via radio <br />telemetry to the mine office. This system was activated in October of 2009. The files are transferred to a <br />secure Applied Geomechanics Data Center where it is organized. Plots and reports can be obtained from <br />the monitoring software. This new monitoring system replaces the previous system. <br />This report contains the following information: <br />In your letter acknowledging receipt of the September 2009 report you stated that "Data for one <br />benchmark, collected on 9/8/09, appears to be anomalous when compared with prior readings at that <br />location. The site in question is 07-GI6 BM, and a displacement of 6.282' is reported for cumulative <br />vertical and 3D displacements. Please verify whether it is accurate...." In response, the anomalous <br />values were the result of an error in the calculation in those cells of the spreadsheet. In reality, the <br />movement at this site was not significant. A revised monitoring sheet for 07-GI6 BM is attached, with <br />corrected values and an additional reading for verification taken in March of 2010. <br />Inclinometer graphs from the new system for the period October 15, 2009 through March 29, 2010 are <br />attached. Movement is measured in "Degrees Tilt" and represents rotation of inclinometer casing. <br />Beginning values can be seen at the October 15th point on the graphs. The data on IN4 (the inclinometer <br />at site 4) also includes a temperature graph. This site is very close to existing operations. There has been <br />no significant movement in the inclinometers during the monitoring period. <br />P.O. Box 187 Craig, Colorado 81626 (970) 824-4401