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Site Conditions The proposed wash plant facility is located west-southwest of the existing wash plant within the Twentymile Coal-Foidel Creek Mine. An existing 48-inch overland conveyor runs through the proposed building site. The site was covered with 6 to 12 inches of snow at the time of our investigation and appeazed to be vegetated with grasses and weeds. It appeazs that previous grading has occurred throughout the site with the cutting of the natural overburden soils and the placement of 1 to 6 feet of fill materials across the proposed building site. In addition, a large fill pile was located in the azea of the proposed screening building. The topography of the site is highly vaziable due to the previous site grading and fill piles, and generally slopes gently to strongly down to the west on the order of 2 to 15 percent It appeazed that a maximum elevation difference of approximately 10 to 15 feet exists across the proposed building site. Field Investigation The field investigation for this project was conducted on February 21, 2007. Seven (7) test holes were advanced at the approximate locations shown in Figure #2 to determine the subsurface conditions. Locations of the test holes were determined by pacing from the staked building locations. No test holes were advanced on the north side of the existing conveyor due to the presence of underground utilities in this area. The test hole elevations were determined by interpolating from topographic plan provided by the client. The test holes were advanced through the existing fill materials, overburden soils and bedrock materials with 4-inch diameter continuous flight augers. The test holes were advanced with an all-terrain rig mounted with a CME 55 drill rig. A representative of NWCC, Inc. logged the test holes. Samples of the subsurface materials were taken with either a California Liner sampler or a standazd split spoon sampler. The samplers were driven into the various strata with blows from a 140-pound hammer falling 30 inches. This test is similar to the standard penetration test described by ASTM Method D-1586. Penetration resistance values, when properly evaluated, indicate the relative density or consistency of the soils and bedrock materials. Depths at which the samples were taken and the penetration resistance values aze shown on the logs of the exploratory test holes in Figure #3. The Legend and Notes associated with the test hole logs are shown in Figure #4. Laboratory Investigation Samples obtained from the exploratory holes were examined and classified in the laboratory by the project engineer. The laboratory testing included standazd property tests, such as natural moisture contents, density, grain size analyses and liquid and plastic limits. Swell-consolidation tests were also conducted on relatively undisturbed samples of the natural clays and bedrock materials to determine [he swell- Job Number: 07-7442 Nw'CC, Inc. Page 2