2011-06-30_REVISION - M1981302 (13)

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7 be used for earth darn design. This value is reasonable acceleration given the geologic environment of the levee and was input in the geotechnical analysis of the earthquake condition. Ground Water. Ground water measurements were taken In the test holes and test pits. By interpolating between test holes and observed seepage evidence, the surface of the ground water table was estimated to slope down slightly in a northerly direction and projected from about the bottom of South Boulder Creek. This resulted in its location about 2 feet below the bottom of Dry Creel{ Ditch #2- See . Appendix C shows the locations water seeps from the ground on the levee side of the reclaimed gravel pit. The natural ground water level was intercepted during mining of the pit and it is apparent the ground water is seeping from the ground along the opposite side (unrest side) of the gravel pit from the levee. This water is collected in a ditch that conveys it to another ditch that is several tens of feet from the landside of the levee in the floor of the gravel pit than eventually conveys the grater out of the pit area. From our review of the survey information in Appendix C, we have concluded it probable that the water exciting the seeps is partly ground grater and partly water lost from Dry Creek Ditch #2 to the very shallow ground water table, we believe the seeps between stations 143 + 00 and the west abutment (station 150 + o ) of the levee are dominantly ground water fed. The seeps between stations 1 + 00 and 1 oo are likely fed by ground water but we have been unable to confirm there is no contribution from ditch water loss. We believe the seeps between 1 0 and 111 + 00 are likely substantially fed by ditch water loss to the ground water but we have been unable to confirm that the seeps would not continue solely from ground water in the absence of the contribution of ditch water. FLATIRON COMPANIES LEVEE AT DEEPS FARM PIS` DTUT 25,385