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- 8 - <br />• SUBSOIL CONDITIONS <br />The subsoil, bedrock and water table conditions were <br />investigated by observing surface exposures and excavating one to two <br />test pits at each pond site. The test pits were opened utilizing a <br />backhce and, in some instances, hand excavation where surface moisture <br />conditions prevented vehicular access. Fig. 1 shows the general pond <br />locations. Figs. 2 through 15 show the locations of test pits and <br />proposed embankment locations. Laboratory testing was performed on <br />selected sales of the subsoils to accurately classify them in <br />accordance with the Unified Soil Classification System and to <br />determine their engineering properties. <br />Generally, the subsoils consisted of nil to 1 foot of topsoil <br />overlying nil to 6 feet of medium to high plasticity clay, except in <br />Test Pit J-1 where 1 foot of clayey sand overlies the clay. Clayey <br />sand and gravel was encountered beneath the upper clay at Pond Sites I <br />and K. Stiff, weathered claystone bedrock was encountered in several <br />of the test pits at depths 1 to 6 feet below the ground surface. <br />Cong~etent claystone and sandstone bedrock was generally found at <br />depths 1 to 6 feet. Bedrock was not encountered in hand excavated <br />test pits F-1, G-1, I-1 and J-1 at 3 to 3.5-foot depths. weathered <br />bedrock was exposed in the bottom of Test Pit M-1 at depth 7 feet. <br />Generally, the upper clay soils, weathered claystone and <br />claystone bedrock are moderately to highly plastic and slightly sandy <br />to very sandy. The sandstone bedrock is generally fine to <br />medium-grained and silty. Gradation test results of the typical <br />subsoils are presented on Figs. I9 through 21. Results of hydrometer <br />