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sands and silty sands, are in a dense condition. The groundwater is encountered at an approximate depth of 60 feet. It is recognized that the project will result in loss of agricultural land. However, the site is bounded by urban growth to the north, west, and south, thereby making the site compatible with surrounding existing residential uses. 4. Seismicity The preliminary Seismic Element study for San Joaquin County states that the major seismic hazard to San Joaquin County is motion resulting from seismic dis- turbances on distant or large fault systems. These large fault systems include San Andreas, Calaveras, and the Hayward Faults. There is also a possibility of seismic activity in the Stockton -Tracy Fault, which crosses the center of the County in a northeasterly direction. For conservative recurrence interval of the maximum probable earthquake varies from 50 tp 200 years. The anticipated maximum bedrock acceleration is estimated to be 0.3 G's in Stockton. Enclosed as part of this report is a map from the Seismic Element Study showing the faults, their more recent epicenters, and their magnitude. Possible effects of seismic motion in San Joaquin County include potential landslide activity, liquefaction, subsidence and structural damage due to shaking. Landsliding will not be a problem in this part of San Joaquin County. Lique- faction is not indicated as a problem at this site due to the moderately high density of the granular soils at the site and the surcharge weight of the cohesive sur- face soils. Grading standards, including inspection procedures outlined in Chapter 70 of the Uniform Building Code, will be followed. Use of seismic none 3 construction standards, as outlined in the Uniform Building Code 1973 Edition, will also be followed. 5. Hydrologic Conditions a. Surface Waters -- There are no lakes, streams, rivers, or other types of open waterways within the project boundaries. Rainwater will naturally drain to the southwest at a very slow rate. There is a drop of about 8" across the property. The USGS 15' Series of Quad Maps for the Burnham (1912) and Waterloo (1907) Quadrangles show an old slough meandering through the property from northeast to southwest. This channel terminated on the property and was never used as a drainage channel. Being slight, it was filled when the land was levelled. It is visible now only because vegetation and soils are affected by the differential compaction and drainage in the old channel. -4