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3.3.3 East Panel Landslide Geotechnical Evaluation <br /> An East Panel landslide occurred on October 8, 2006. A geotechnical evaluation program was <br /> designed by Agapito Associates Inc. (AAI). This program was designed to determine the slide plane <br /> and to determine parameters for future development of G and K pit. This program also included <br /> sites in Z dip pit. <br /> A total of three sites were completed with inclinometers, four sites with piezometers and several <br /> sites with surface benchmarks. Surface benchmarks are used to monitor changes in down-dip <br /> displacements over time. Data retrieved from inclinometers provides the deflection of the casing as <br /> a function of the depth below the collar. Plots are developed of deflection versus depth. <br /> Piezometers are used to monitor water levels. <br /> The monitoring was performed in accordance with the recommendations of Agapito Associates Inc. <br /> as described below: <br /> • Once per month during the dry season. <br /> • Once per week during the wet months of spring (April-May) and fall (September-October). <br /> • Once per day after major precipitation (rainstorm) events > 0.50 inches for 3—4 days <br /> transitioning to weekly for 1 —2 weeks and back to a normal schedule thereafter. <br /> In September of 2008, the required monitoring frequency was reduced (by AAI)to the guidelines <br /> shown below: <br /> • Once per month <br /> • Once per week for two weeks following a major rainstorm event(> 0.5 inches) <br /> In October of 2009, the original monitoring program was replaced with a state-of-the-art program <br /> that was developed as a part of a new ground control plan submitted to MSHA in advance of <br /> resuming mining operations in the land slide area. The monitoring plan was developed with the <br /> assistance of AN and Applied Geomechanics. <br /> TMI is currently contracted with SNC Lavalin Transportation USA Inc. for the installation, <br /> commissioning, and ongoing data collection from the landslide monitoring equipment on the <br /> Trapper Mine Site. <br /> With the new system, three GPS stations were constructed in the slide zone. A fourth station <br /> located outside the slide area acts as a reference and repeater station. Four boreholes were drilled. <br /> These holes were drilled for instrumentation installation only; no characterization core holes were <br /> completed at these sites. Each hole was cased with inclinometer casing. Each borehole contains <br /> two fully grouted piezometers and three in-place inclinometers. Each instrumentation station is <br /> equipped with audible sirens and strobe light alarm systems, radio equipment, solar panel and <br /> batteries. <br /> JUL 0 8 2014 3-27a Revision: 10R -07 <br /> approved: <br />