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A layer of natural topsoil and organic materials was encountered at the ground surface in all of the test <br />• holes and test pits. The topsoil and organics layer ranged from 6 to 18 inches in thickness. <br />The natural clays were slightly to very sandy, low to highly plastic, very stiff to medium stiff, slightly moist <br />to wet and brown to gray in color with calcareous deposits. Samples of the clays classified as CL to CI.- <br />CH soils in accordance with the Unified Soil Classification System. <br />claystone-shale bedrock was encountered below the clays or sands and clays in all of the test holes and in <br />two of the test pits at depths ranging from 5 to 17 feet beneath the existing ground surface. The claystone- <br />shale bedrock materials were slightly sandy, fine grained, moderately to highly plastic, hard to very hard, <br />slightly moist to moist and gray in color. Samples of the claystone-shale bedrock materials classified as CL <br />to CL-CH soils in accordance with the Unified Soil Classification System. <br />The unconfined compressive strength tests conducted on samples of the natural undisturbed clays indicate <br />that the samples tested exhibited compressive strength values ranging from 1,700 to 11,700 psf. Whereas, <br />the remolded clay samples exhibited compressive strength values ranging from 3,000 to 8,100 psf. The <br />unconfined compressive strength tests conducted on relatively undisturbed samples of the claystone <br />bedrock materials indicate that the samples exhibited compressive strength values ranging from 6,100 to <br />18,000 psf. The classification and unconfined compressive strength test results are summarized in the <br />attached Tables 1 and 2. <br />Swell-consolidation tests conducted on samples of the natural, undisturbed clays exhibited a low to <br />• moderate consolidation potential under relatively light loads. The clays also exhibited a low to moderate <br />swell potential when wetted under a constant Ioad and then exhibited further consolidation when the loads <br />were increased. The swell-consolidation test results are shown in Figures #b through #$. <br />Tri-axial shear tests were conducted on relatively undisturbed samples of the natural clays obtained from <br />test hole 3 at a depth of 8 to 9 feet. The tri-axial test results indicate that the sample of natural clays yielded <br />an effective cohesion value of 0 psf and an effective phi angle of 34.0 degrees. The tri-axial shear test <br />results are shown in Appendix A. <br />Falling head permeability tests conducted on relatively undisturbed samples of the natural clays exhibited <br />permeability's on the order of 1.0 x 10"7 to 6.0 x 10-9 centimeterslinch and the permeability tests conducted <br />on the remolded clay samples exhibited permeability's on the order of 1.6 x 10"~ to 3.0 x 10~ <br />centimeterslinch. The falling head permeability test results are shown in Appendix B. <br />The pin hole dispersion tests conducted on samples of the natural, undisturbed clays and the remolded clays <br />indicate that the clays are Iv'on-Dispersive. The pin hole dispersion test results are shown in Appendix C. <br />Crroundwater seepage was encountered in two of the test holes at the time of drilling and in one of the test <br />pits shortly aftex it was excavated. The groundwater seepage was encountered at depths ranging from of 6 <br />to 10 feet below the existing ground surface in bottom of the drainage Swale. ~It should also be noted that <br />the clays encountered in the test holes and pits advanced in the Swale bottom and near the center of the dam <br />and reservoir had a noticeable moisture change at depths ranging from 5 to 8 feet beneath the existing <br />• <br />Job Number: 07-7556 NV/CC, Inc, Page 5 <br />