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sand, eolian (wind blown) deposits of loose sand, and compact and very fine sand. Exploratory borings confirmed the presence of undifferentiated sands containing varying quantities of silt and clay to a depth of 48 feet. The California Department of Conservation's Division of Mines and Geology Surface Mining and Reclamation Act Designation Report No. 9R, Designation of Regionally Significant Construction Aggregate Resources in the Stockton-Lodi Production-Consumption Region, May 1989 (Revised July 1990) delineated Sectors D-7 and D-8 overlying the majority of the project site. The site is located in UBC Seismic Zone 3 and there are no known faults that cross the site. The two closest active, potentially active, or capable faults to the site are the Great Valley Fault Zone located 13 miles west-southwest and the Foothills Fault System located 33 miles east-northeast of the project site. The site is listed in the Uniform Building Code as a Seismic Zone 3; therefore there is the reasonable, although slight, possibility (10% probability of accedence in 50 years) that the site will be subjected to a moderate amount of shaking from a seismic event during the life of the project. HYDROLOGY The project site is located in a basin created by the State Route 120 embankment to the north, the Union Pacific Railroad embankment to the south and east and the San Joaquin River levy to the west. As a result, no significant amount of drainage currently enters the site. There is a drainage easement located at the southwest corner of the property that would permit the dischargm of drainage from the site to the south. This drainage would ultimately discharge into the San Joaquin River via a City of Manteca maintained outfall structure. However, with the proposed quarry, all storm water will be contained within the quarry limits. Based on the soil borings performed by Neil O. Anderson & Associates, Inc., the ground water elevation beneath the property is estimated at approximately 3 feet below mean sea level or approximately 15 feet beneath the ground elevation. Groundwater is maintained approximately 30 feet below natural grade at the Oakwood Lake sand pit located to the south of this project on the other side of the Union Pacific Railroad embankment. A proposal has been put forth by the owners of the Oakwood Lake Resort and quarry to develop the area into a residential subdivision'. With the development of the residential subdivision, the artificial lowering of the groundwater will be required to continue in perpetuity. Soms Soils in the project area have been formed from alluvial flooding and are generally rated as Class III if irrigated and Class IV without irrigation. As such, these soils are marginal for farming and require careful crop management to be successful. Recoverable topsoil depths range from approximately 1 foot to 4 feet. Soils identified by the Soil Survey of San Joaquin County (SCS 1992) include: ' Pg. 4.4-1 Oakwood Lake Expansion Final Environmental Impact Report, September 2000, Mills Associates Surface Mining Application Page 2 Landmark Lathrop,L.L.C.