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<br />5.A.(5)(d)(II)(B) The most current Probable Maximum <br />Precipitation estimates developed by the Office of Hydrology, National <br />Weather Service, NOAA Hydrometeorological Report Series may be used <br />for determining probable future flows. Snowmelt conditions shall be <br />considered as base flow when appropriate. <br /> <br />5.A.(6) A geotechnical report which complies with these rules, <br />and evaluates the stability of the foundation, dam, and the slopes of <br />the reservoir rim, and demonstrates that sufficient material is <br />available to construct the dam as designed. The Geotechnical report <br />shall include, but not be limited to, the following: <br /> <br />5,A.(6)(a) For all classes of dams include information on the <br />geology of the local area and dam foundation. Additionally, for Class <br />I dams and large and intermediate size Class II dams include data on <br />faults and the fault history which may affect the dam, the seismicity <br />of the area and region, and a seismic evaluation of the reservoir <br />perimeter slide potential, <br /> <br />5,A.(6)(b) For Class I and Class II dams foundation <br />investigations shall include drilling to and penetration into bedrock <br />or 1.5 times the height of the dam, whichever is less; development of <br />drilling logs; conducting standard penetration tests; making field <br />soils classifications; determination of the water level in each drill <br />hole; in situ permeability; gradation tests of foundation materials <br />especially in the area of drains; and if applicable, determination of <br />whether liquefaction potential is present and whether clayey materials <br />exhibit residual strength properties. <br /> <br />5.A.(6)(c) For Class I and Class II dams, the report shall <br />demonstrate that adequate borrow materials are available for con- <br />struction. As a minimum, the following qualitative tests shall be <br />included: <br /> <br />1. Gradation of the materials; <br /> <br />2. Laboratory soils classifications; <br />3, Compressibility of soils; <br /> <br />4. Remolded permeability of materials; <br /> <br />5. Shear strength of materials (dynamic shear strength <br />tests if applicable; <br /> <br />6. Proctor compaction test curves; and <br /> <br />7. The presence of dispersive clays. <br /> <br />- 19 - <br />