Laserfiche WebLink
2.05.3(b)ic) <br />• Logs of the test holes are shown on Figures 2.05.3(6)(c)-2, 2.05.3(6)(c)-3, <br />2.05.3(6)(c)-4 and 2.05.3(6)(c)-5. <br />Soil conditions encountered during the test hole drilling in the <br />foundation area of the dams are somewhat erratic and vary with depth. <br />Generally, 0.5 to 6.5 feet of loose to medium dense sand, silty <br />clay and clayey silt, and coal slag was encountered over very sandy <br />clay to clayey sand with gravel and transported sandstone and clays tone <br />pieces of up to 9.5 feet thick. Below these depths, medium plasticity <br />clay and gravelly clay to clayey gravel with scattered sandy lenses <br />were encountered. Claystone and sandstone bedrock was encountered <br />below depths of 8.5 to 17 feet. The top three to seven feet of <br />bedrock was weathered in test holes 1-2,1-3,3-2 and 3-3. Medium hard <br />to hard bedrock was found below the weathered zones; however, some <br />additional weathered zones were encountered within the bedrock in <br />test holes l-1 and 3-1 of 0.5 to 3.0 feet thickness. A 3.5 foot <br />deep void was found below elevation 6,299.5 feet in test hole 3-1. <br />As can be seen on Previously Affected Land Map, 2.04.3(3)-1, there <br />• are several exploration trenches within the permit area. This void <br />is one of the trenches. <br />Water was encountered at depths of 10.5 to 15 feet at the time of <br />drilling in test holes 1-1 through 1-3, 2-1 and 2-2. <br />A free water level was found in the test holes at depths of 13 to <br />18.5 feet when checked on October 25, 1979. In addition, test <br />hole 1-2 was plugged at depth 2 feet and test hole 2-1 was covered <br />over and the water level could not be verified. <br />The test pits were dug in the anticipated borrow areas for the <br />proposed dam structures. Generally, silty and sandy to very <br />sandy clays were encountered in the test pits to a depth of 12 feet, <br />the maximum depth explored. The laboratory program consisted of <br />classification tests, maximum density and optimum moisture <br />determinations (Proctor tests), consolidation tests, unconfined <br />compression tests, and permeabilty tests. <br />•- Results of~the laboratory testing are shown on Table 2.05.3(6)(c)-1. <br />113 <br />