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September 27, 2012 <br />Mr. Jared Ebert <br />Environmental Protection Specialist <br />Colorado Division of Reclamation, Mining, and Safety <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 <br />Dear Mr. Ebert: <br />RE: Semi - annual Geotechnical Monitoring Report - September 2012 <br />Trapper began submitting semi - annual monitoring reports to the Division, beginning March 2008 with the last <br />report sent on March 30, 2011. Trapper has been monitoring the 2006 landslide area for movement through the <br />use of a continuous monitoring system. <br />Section 3.3.3 of Trapper's permit details the initial configuration of the monitoring system. Due to normal <br />advance mining operations, the system at site 5 was decommissioned on August 22, 2012 and site 6 was <br />decommissioned on September 24, 2012. A map has been attached showing the location of all four monitoring <br />sites. Inclinometer, piezometer and surface displacement graphs for all four sites covering the time period of <br />March 30 through September 26, 2012 are attached. The monitoring system has shown no significant <br />movement during the period. <br />On July 6, 2012 the server that supports the slope monitoring software went down. A new server was installed <br />and on July 24, 2012 data began to be recorded. There was no loss of data for the inclinometers or <br />piezometers. Due to the memory on board the loggers some of the GPS data was lost. A new baseline was <br />used which caused a break in the GPS data. One set of displacement graphs show data from March 30, 2012 <br />through July 6, 2012. The second set of displacement graphs illustrated data collected from July 24, 2012 <br />through September 26, 2012, except for the GPS systems located at site 5 and 6, which have data up to the <br />time of their decommission. <br />The inclinometer located at site 8 did show some movement around the time of August 22, 2012. While <br />inspecting the area, it was discovered that the inclinometer casing was broken just above the surface. There <br />were cows in the area, and it was determined that one of the cows rubbed up against the casing and broke it, <br />causing the movement shown on the graph. The casing has been splinted together and a fence has been <br />placed around the monitor site. <br />In your letter responding to the March 2012 report, you inquired why the pore pressure at the "M" level is lower <br />than the pore pressure at the "L" level at station 8. The field notes for this site indicate that about 160 feet of <br />tremmie pipe broke off in the hole. This may be giving a path for the water causing the lower water pressure at <br />the deeper depths. <br />Please contact me if you have any questions. <br />Sincerely, <br />C /L° <br />Tonia Perkins, P. E. <br />Senior Mining Engineer <br />P.O. Box 187 <br />TRAPPER MINING INC. <br />RECEIVE <br />OCT 0 12012 <br />Division of Recl on, <br />Mining & Safety <br />Craig, Colorado 81626 (970) 824 -4401 <br />