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• SUBSURFACE CONDITIONS <br />The subsurface conditions encountered across the project site were variable and generally consisted of <br />a layer of topsoil overlying natttral clays, sands, sandstone bedrock and claystone bedrock to the <br />maximum depth investigated, 42 feet. <br />The thickness of the topsoil was variable and ranged Crom 0 to 4 feet in depth. Natural clays were <br />encountered beneath the topsoil in a majority of the test holes. The clays were encountered to depths <br />of 2 1/2 to over 35 Ceet below the existing ground surface. The clays were slightly sandy to very sandy, <br />occasionally silty, medium to highly plastic, soft [o hard, slightly moist to very moist and brown in color. <br />The clays classified as CH to CL-SC soils in accordance with the Unified Soil Classification System. <br />Sands were encountered in test holes (#15 and #16). The sands extended to depths of 15 to 38 feet <br />below the ground surface. The sands were silty to shghtly clayey, low to non plastic, fine grained, loose <br />to meditnn dense, slightly moist to wet and brown in color. The sands classified as SM soils in <br />accordance with the Unified Soil Classification System. Natural sands and clays were encountered at <br />depths of approximately 10 and 17 feet in test holes #22 and #25, respectively. The sands and clays <br />were low to moderately plastic, Loose to soft, fine grained and occasionally gravelly, wet and dazk <br />brown to brown in color. The sands and clays classified as CL soils in accordance with the Unified Soil <br />Classification System. <br />• Sandstone bedrock was encountered below the overburden soils in test holes 3, 3, 10, 13 to 17 and 20. <br />The dept}[ a[ which the sandstone bedrock was encountered was variable and ranged from as shallow <br />as 2 1/2 feet in test hole 20 to as deep as 38 feet in test hole 15. The sandstone bedrock was silty with <br />occasional silts[one interbeds, low [o non plastic, fine grained, medium hard to very hard slightly to <br />highly cemented dry to moist and light brown is color. The sandstone bedrock classified as SM and <br />ML soils in accordance with the Unified Soil Classifwtion System. claystone bedrock was <br />encountered in test holes Z, 4, 6, 9, 17, 18, 19 and 21 through 2b. The depth at which the claystone <br />bedrock was encountered was also variable and ranged from as shallow as 4 1/2 feet in test hole 6 [o as <br />deep as 26 feet in test hole 25. The claystone bedrock was silty to slightly sandy, medium to highly <br />plastic, medium hard to very hard, moist and brown [o grayish brown in color. The claystone bedrock <br />classified as CL to CH soils in accordance with the Unified Soil Classification System. <br />Free groundwater was only encountered in test holes 11, 15, 22, 24 and 25 at the time of drilling; <br />however, when measured 1 to 40 days after the drilling was completed, groundwater was also <br />encountered in test holes 2, 12, 13 and 14. The depth at which the groundwater was encountered and <br />the number of days after the drilling was completed that the measurements were taken are shown on <br />the test hole loge. Ic should be noted that groundwater conditions can be expected to fluctuate with <br />changes in precipitation and runoff. <br />SITE GRADING RECOMMENDATIONS <br />The natural slopes on this site could become unstable as a result of construction operations. Design <br />and construction considerations must be given to this potential instability in order to successfully <br />construU and maintain the proposed haul road alignment. To investigate the potential stability of the <br />5 <br />