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1 <br />t•lodified California Barrel and Standard Split Spoon Barrel Samplers from <br />which standard penetration tests as well as samples for laboratory analy- <br />' sis were obtained. <br />The test holes were located in the general area of the foundations for <br />' the dams. The test pits were located both in the retention and foundation <br />areas from which the borrow for the structures will be obtained. <br />1 <br />SUBSOIL COIIDITIOIIS <br />' Soil conditions encountered during the test hole drilling in the foun- <br />' dation area of the darns are somewhat erratic and vary with depth. Generally, <br />0.5 to 6.5 feet of loose to medium dense sand, silty clay to clayey silt, <br />' and coal slag was encountered over very sandy clay to clayey sand with gravel <br />and transported sandstone and clays tone pieces of up to 9.5 feet thick. Below <br />' these depths, mediwn plasticity clay and gravelly clay to clayey gravel with <br />' scattered sandy lenses were encountered. Claystone and sandstone bedrock was <br />encountered below depths of 8.5 to 17 feet. The top 3 to 7 feet of bedrock <br />t was weathered in test holes 1-2, 1-3, 3-2 and 3-3. 14edium hard to hard bed- <br />rock was found below the weathered zones; ho~.~ever, some additional weathered <br />' zones were encountered within tare bedrock in test holes 1-1 and 3-1 of 0.5 to <br />' 3.0 feet thickness. A 3.5 foot deep void was found below elevation 6,299.5 <br />feet in test hole 3-1. Sandstone was encountered above the void in this test <br />' hole: the void could be a cavern or possibly the overbearing sandstone is <br />transported. <br />Llater was encountered at depths of 10.5 to 15 feet at the time of drill- <br />' ing in test holes 1-1 through 1-3, 2-1 and 2-2. A free water level was found <br />in the test holes at depths of 13 to 1B.5 feet when checked on October 25, <br />' 1979. In addition, test hole 1-2 was plugged at depth 2 feet and test hole <br />2-1 was covered over and the water level could not be verified. <br />1 <br />-2- <br />1 <br />