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11 <br />1 <br />Descriptions and visual classifications of soil samples were logged in accordance with <br />the ASTM D 2487 or ASTM D 2488 Unified Soil Classification System. The <br />completed test boring reports are provided in Appendix A, along with an explanatory <br />sheet deftning the terms used on the reports. The recovery and rock quality <br />designation (RQD) were recorded for cored bedrock. Sampling information, and <br />other pertinent field data and observations are also included in the test boring reports. <br /> B. Hand Auger Borings <br /> Ten hand auger borings (HA-1H to HA-lOH) were performed along the shores of the <br /> existing ponds at locations that could not be accessed by standard drilling equipment. <br /> The purpose of these borings was to evaluate the characteristics of reclaimed slope <br /> material along the sides of the water-511ed gravel pits. Borings were extended as <br /> deep as possible, ranging from 1 ft to 8 ft bgs. Representative soil samples were <br /> retrieved from each hole using ahand-driven split spoon sampler. A summary of <br /> hand auger borings is included in Table I. Boring locations are shown on Figure 2. <br /> C. Test Pits <br /> Twenty-two test pits (TP-1 through TP-22) were performed for the clay borrow <br />investigation described within this report. Samples were collected from each test pit. <br /> Representative samples of coarse alluvium used for backfill mix design testing were <br /> collected from two test pits (TP-13 and TP-14). Test pits were extended up to 14 ft <br />bgs. Descriptions and visual classifications of soil samples were logged in <br /> accordance with the ASTM D 2487 or ASTM D 2488 Unified Soil Classification <br /> System. Test pi[ reports ate provided in Appendix D. <br /> <br /> D. Field Testing <br /> In situ water pressure testing (packer testing) was performed in the cored section of <br /> thirteen borings to provide data used to calculate the approximate permeability of <br /> bedrock. A single packer system was used for the testing. For select borings, <br /> different depth intervals were tested within the cored portion of the boring, with the <br />_ test interval increasing by approximately 5 ft for each test. During each test, the <br /> bedrock was subjected to three pressures, 1/3, 2/3, and 3/3 of the calculated <br /> maximum overburden pressure. Pressures were maintained for ten-minute intervals, <br /> or until water flow had equilibrated. A summary of calculated permeability results is <br /> presented in Table II. <br /> E <br />Cla <br />Borrow Investi <br />ation <br /> . <br />g <br />y <br /> The results from test borings indicate that the amount of fine material (passing the <br /> Jl200 sieve) that a contractor may require for an effective backfill for slurry wall may <br /> not be available in the excavated material from the slurry trench. Therefore, an <br /> alternate source of clay or silt would be required to achieve the desired percentage of <br /> fine material in the backfill mixture. As a result, a clay borrow investigation was <br />