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The locations of the test holes and pits were determined in the field by a representative of NWCC, Inc. and <br />Twentymile Coal Company. The elevations of the test holes and pits were measured by the client after they <br />were completed. An engineer from of NWCC, Inc. logged the test holes and test pits as they were <br />advanced, as well as obtained soil and bedrock samples for classification and laboratory testing. <br />Samples of the subsurface materials were taken v~ith a 2-inch I.D. California liner sampler. The sampler <br />was driven into the various strata with a 140-pound hammer falling 30 inches. This test is similar to the <br />standazd penetration test described by ASTM Method D-1586. Penetration values, when properly <br />evaluated, indicate the relative density or consistency of the soils. Large and small disturbed bulk samples <br />were also obtained from the test pits excavated in the borrow areas. Depths at which the samples were <br />taken are shown on the Logs of the Exploratory Test Holes in Figure #3 and in the Logs of the Exploratory <br />Test Pits in Figure #4. The Legend and Notes associated with the logs are shown in Figure #5. <br />Slotted, lti4-inch diameter PVC casing was also installed in two of the test holes drilled in the center of the <br />proposed embankment. The bottom 10 to 15 feet of casing was slotted and the upper portions of the holes <br />were cased with solid PVC. The annulus between the casing and perimeter of the test hole was filled with <br />pea gravel and the upper 3 feet of annulus was backf"illed with on-site clay materials. <br />Measurements of the water levels were made in the test holes by lowering a weighted tape into the casings <br />shortly after completion of the drilling and 1 day after the drilling was completed. The depth of the water <br />levels measured and the number of days subsequent to drilling that the measurements were taken aze shown <br />on the Logs of Exploratory Test Holes, Figure #3. <br />• <br />Laboratory Investigation <br />The laboratory investigation was conducted to study the engineering characteristics of the material samples <br />obtained from the test holes and borrow area test pits. This section includes a discussion of the laboratory <br />test procedures, figures, tables and appendices presenting the. test results. <br />Samples obtained from the test holes and test pits were examined and classified in the laboratory by the <br />project engineer. Laboratory testing included standard property tests, such as natural moisture contents, dry <br />density, grain size analyses, liquid and plastic limits, swell-consolidation tests, moisture-density (Proctor) <br />relationships, unconfined compressive strength tests, falling head permeability tests, tri-axial sheaz tests and <br />pinhole dispersion tests. The results of the swell-consolidation tests are shown in Figures #6 through #8; <br />the results of the moistwe-density relationship (standard Proctor) tests are shown in Figures #9 through <br />#11; and results of the gradation hydrometer tests are shown in Figures #12 through #14. The results of the <br />classification, moisture-density, and unconfined compressive strength tests conducted on samples obtained <br />from the test holes drilled in the embankment azea are summarized in the attached Table 1. The results of <br />the classification, moisture-density, and unconfined compressive strength tests conducted on samples <br />obtained from the test pits excavated in the borrow area are summarized in the attached Table 2. The <br />laboratory testing was conducted in general accordance with recognized test procedures, primarily those of <br />the American Society for Testing and Materials (ASTM) and the American Association of State Highway <br />and Transportation Officials (AASHTO). <br />Job Number: 07-7556 NWCC, Inc. Page 3 <br />