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Geotechnical Data Report Bruce Park Dam <br />Bowie Resources, Limited <br />April 2001 <br />Three borings were planned to be drilled within a mapped landslide area on the right <br />(northwest) shore of the reservoir. These borings were not drilled due to permitting, access, <br />and time restrictions imposed by the U.S. Forest Service. <br />Five borings were drilled at the main dam: BD-101 and BD-102 at each abutment; BD-103 at <br />the toe near the maximum section; and BD-105, and BD-105A at the crest near the maximum <br />section. Two borings were drilled at the saddle dam: BS-102 at the crest near the maximum <br />section; and BS-104 on the slope above the right abutment. All borings were drilled <br />vertically. Locations of the borings drilled are shown on Figure 2. <br />3.3.9 Drilling Methods <br />All borings were drilled by Agapito Drilling, Inc. with a track-mounted Acker <br />MP-5C rig. The borings were advanced through the dams and portions of the <br />foundation soils and weathered bedrock using hollow-stem augers. "Disturbed" <br />sampling methods included driving a 1-3/8-inch I.D. split-spoon sampler ahead of <br />the augers, and collecting continuous dry core as the borings were advanced with <br />a 3-'/4-inch I.D. sampler inside the augers. "Undisturbed" samples were collected <br />by pushing a 3-inch I.D. thin wall (Shelby) tube ahead of the augers. <br />After encountering auger refusal, the borings were advanced in the glacial <br />deposits and bedrock using HQ size wireline coring methods. The hollow-stem <br />augers were used as temporary casing for the HQ coring: Water was generally <br />used as the drilling fluid. Bentonite mud was mixed in the drilling fluid during <br />drilling of BD-102 because of difficulties during coring. <br />3.3.2 Logging Procedures <br />GEI's field engineer prepared field logs for each boring and recorded results for each <br />packer test. Soil and bedrock samples were visually classified and logged to <br />identify subsurface stratigraphy and to observe features important in evaluating <br />soil and rock mass properties. Soil classifications, moisture, stiffness, density, <br />particle sizes and other descriptions were recorded for soil samples. For rock <br />core, the rock type, lithologic descriptors, weathering, fracturing, sample recovery <br />as a percentage of the sample interval, rock quality designation (RQD), coring <br />time, drilling observations, and other descriptions during drilling were recorded. <br />The rock and soil classification system used during our investigation is generally <br />based on criteria developed by the U.S. Bureau of Reclamation (USBR). These <br />criteria are presented in Appendix A. Boring logs are presented in Appendix B. <br />GEI Consultants, Inc. 5 99292 01_,a 16 Geotechrncal Oata Report