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Page 3 ti.. ... Approximate 80-Acre Property September 25, 2001 Job No. 1107-013 REGIONAL SETTING PHYSICAL SETTING SOURCES Sources used to determine the regional setting during this study have included the following: • 1977 CDMG Geologic Map of California(1:750,000) • 1994 CDMG Fault Activity Map of California(1:750,000) • 1981 CDMG Geologic Map of the Sacramento Quadrangle (1:250,000) • 1968 USGS Linden Quadrangle (1:24,000) • Appended EDR Radius Map database listing (including various area maps) GEOLOGICAL/HYDROGEOLOGICAL CHARACTERISTICS Geology The subject property is situated in the central portion of the Sacramento Valley, within the Great _ Valley geomorphic province of California. California Division of Mine and Geology mapping indicates that sands, silts, and clays in the general site vicinity are recognized as the upper member of the Pleistocene-aged Riverbank Formation and the Quaternary aged Turlock Lake Formation. These formations overlay other Cenozoic continental and marine sediments as well as the upper Cretaceous geologic formations of the Great Valley Sequence. The formations within the sequence are generally post-Jurassic, shallowly dipping to the west and several thousand feet thick. The Great Valley sediments are in tum underlain by Mesozoic metamorphic and plutonic rocks of the Sierra Nevada. Hydrogeology Surface Water/Flood Potential The subject property is situated in an area of relatively flat topography; maximum site relief is on the order of about ten feet. Site surface elevations average about 100 to 110 feet above mean sea level; surface gradients and drainage in the general vicinity trend gently to the northwest. An area drainage tributary flows east-west across the central portion of the property; a pond (presently dry) _ is situated on the north-central portion of the property. We did not observe any evidence of suspicious run-off onto or off the subject property during our recent site visit. The appended EDR report indicates that the property is located outside the 100- and 500-year flood zones. Groundwater Information obtained from a Spring 1998 County map indicates that local groundwater is generally encountered within about 130 feet of ground surfaces in the general site vicinity. County groundwater contour maps suggest that the regional groundwater gradient trends south- southwesterly toward a regional zone of depression.