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• R Squared, Inc., Geotechnical Reconnaissance of Idaho Mine Access Road, May <br /> 2010 <br /> • Trautner Geotech LLC, Geotechnical Engineering Observations,for the Wildcat Mine <br /> Access Road for La Plata County, November 2008 <br /> The geotechnical exploration program included drilling seven test borings and excavating <br /> eight test pits, at the approximate locations shown in Figure 2 . The test borings were drilled <br /> with a hollow stem auger drill rig and extended approximately 4 to 20 feet below the existing <br /> ground surface. Test pits were excavated with a backhoe and extended approximately 3 to 7 feet <br /> deep. The engineer logged borings/pits and obtained relatively undisturbed and bulk samples of <br /> the materials encountered. Logs of test borings and test pits are presented in Appendix A. <br /> Bulk samples were collected from the test pits and borings in sealable plastic bags and 5- <br /> gallon buckets. Relatively undisturbed samples were obtained by driving a Standard Penetration <br /> Test (SPT) sampler or a 2-inch-diameter modified California sampler with a 140 pound hammer <br /> falling 30 inches. Blow counts required to advance the sampler were converted to SPT values <br /> and are presented on the boring logs. Selected samples were observed to confirm field <br /> classifications. Selected samples were transported to Terracon Materials Testing Laboratory in <br /> Farmington, New Mexico, and tested for physical properties. Laboratory tests performed include <br /> the following'`: <br /> • Moisture Content (ASTM D2216-10) <br /> • Dry Density (ASTM D7263-09) <br /> • Atterberg Limits (ASTM D4318 — 10) <br /> • Modified Proctor(ASTM D 1557 —09) <br /> The laboratory results are presented in Appendix B. <br /> 3.0 Results <br /> 3.1 Geology <br /> The exposed rock on the through-cut area consists of Terrace Deposits overlying Older <br /> Colluvium. Terrace deposits overlying colluvium are exposed on both sides of the existing <br /> through-cut. Terrace deposits consist of rounded cobbles 1 to 12 inches in diameter in and <br /> clayey sand matrix. The Pleistocene Age Older Colluvium occurs on dissected hill slopes, <br /> ridgelines, and drainage divides as erosional remnants. Texture, bedding and clast lithology <br /> resemble those of colluviums. <br /> ' Test pit/boring locations were surveyed by Mountain Man Surveying of Durango,Colorado. <br /> '` Strength tests were planned but could not be performed as the fraction of oversize particles precluded obtaining a <br /> relatively undisturbed sample that is required for such tests. <br /> Rule 6.5 Geotechnical Stability Technical Revision April 2,2012 <br /> New Access Road Page 2 <br />