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Development Committee -2- <br /> WATER: <br /> The introduction to the report indicates that he groundwater is <br /> at about 88 feet below the surface. The information in the <br /> geotechnical sections indicated that there are two borings that <br /> were dug to a depth of 75 feet. In one of the borings no water <br /> was encountered and the other boring groundwater was encountered <br /> at depth of 62 feet. With only two borings on the site that only <br /> go to a depth of 75 feet, there is not enough information to <br /> determine the groundwater characteristics of the 157-acre site. <br /> The plans indicate that there is a drainage course that runs <br /> along the southern boundary of the site. In reviewing a land use <br /> map for the area, this drainage course is identified as Corral <br /> Hollow Creek and should be shown on the plans. The Typical <br /> Sections should be included on the plans that incorporates this <br /> drainage course to insure that there is adequate setback between <br /> the drainage course and the slope to be excavated. It is being <br /> recommended that 100 foot setback be established as a minimum <br /> from the centerline of Corral Hollow Creek to the top of the cut <br /> slope. <br /> GEOTECHNICAL• <br /> The Mining and Reclamation Plans need to provide detailed <br /> information how the fill slope will be constructed and placed <br /> against the cut slope. Development Title requires the slope <br /> stability factors of safety shall apply as follows: <br /> • A minimum factor of safety at 1 . 5 against static, deep <br /> seated failure. <br /> • A minimum factor of safety at 1. 5 against static, <br /> surficial failure; and <br /> • A minimum factor of safety at 1. 1 against seismic <br /> failure. <br /> It is not clear from the geotechnical information submitted by <br /> Kleinfelder whether the safety factor criteria has been addressed <br /> as required, or that the slope stability analysis includes the <br /> fact that the final 2 to 1 slope is being placed against a cut <br /> slope of 1 1/2 to 1 . <br /> The information in the report indicates that the site will be <br /> excavated to a depth from 31 to 62 feet and reclaimed to a depth <br /> of about 28 feet from the surface. The plans are not clear about <br /> what areas are being excavated to depth of 31 feet; what area are <br />