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MKE shall drill seven boreholes with an emphasis on gathering as much <br />information as possible from each hole. In this way, the previous boreholes <br />can be correlated and conclusions can be drawn as to embankment <br />characteristics and patterns. Four of the holes shall be drilled from the <br />crest of the dam through the embankment and into the foundation. An attempt <br />shall be made in at least one of these holes to reach bedrock. Two additional <br />holes shall be drilled downstream of the maximum section of the dam, with one <br />hole located to either side of the outlet. An attempt shall be made to <br />determine and verify the depth of bedrock downstream of the dam. Utilizing <br />the information obtained from these holes and the holes drilled 'from the <br />crest, an estimate of the bedrock elevation beneath the maximum section of the <br />dam shall be made by interpretation of the drill hole data. A seventh drill <br />hole shall be located in the area of the primary and secondary spillway dike. <br />This hole shall be drilled from the crest of the dike, with an attempt made to <br />advance the hole to and into bedrock. <br />The boreholes shall be systematica led by the split spoon or California <br />method at 5 -foot intervals <br />1,7 77 <br />E r ch es in material are detected. <br />Standard penetration tests ` a '1 b, 4dO 'd when samples are taken. <br />Borehole permeability tests shah lS rtffed every ten feet to determine the <br />distribution of more or le ios strata. Undisturbed samples shall be <br />obtained of the embankment and "'foundation, as required for classification in <br />the laboratory, and determination of strength characteristics for use in the <br />stability and seepage analyses. In the event one or more of the boreholes <br />does reach bedrock, it shall be cored and packer- tested to a depth of at least <br />ten feet. Upon completion of a borehole, multiple stage, standpipe piezometers <br />shall be installed in strata of varying permeability within the hole in order <br />to allow measurements of the phreatic surface. In addition, several test pits <br />and trenches will be excavated on and around the dam to correlate the physical <br />characteristics of the embankment and the foundation with the samples obtained <br />from drilling, where a particle size restriction exists. Test pits shall also <br />be used to assess the thickness of riprap and the quality of the upstream <br />impervious blanket. In addition, seismic lines shall be run along the crest <br />of the dam in order to define the dam /foundation contact and the top of <br />bedrock. <br />