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The project has no potential to alter the geologic integrity of the study area or create significant geologic hazards on-site. No mitigation of geologic impacts is deemed necessary. Seismicity - The Maximum Credible Rock Acceleration map published by the California Division of Mines and Geology C.D.M. FG—.) shows the study area to be within an area with a predicted seismic acceleration range of 0.2 g or less which is the lowest rating in the State. The Earthquake Epicenter Map of Califor- nia, also by the C.D.M. &G., indicates that no earthquake epicenters of Richter magnitude four or greater have been mapped in San Joaquin County between 1900 and 1978. The closest fault shown on the Fault Map of California, (C.D.M. & G.), is the Stockton Fault, approximately six miles to the south. Based on the evidence presented, it appears that the site could reasonably be considered to be among the quietest seismic areas within the State of California. Due to the nature of the project, there would be no possibility for significantly altering the seismic hazard potential of the study area. Climate San Joaquin County enjoys a climate commonly referred to as a Mediter- ranean type with cool, moist winters and hot, dry summers. The project site is located slightly south of the zone of divergence of incoming marine air. During the summer, air from the coast enters the Valley by way of the San Francisco Bay gap and Carquinez Strait, then undergoes rapid modification of temperature and relative humidity (see Figure 3). Part of the airflow turns northward into the Sacramento Valley and part turns southward into the San Joaquin Valley. During late fall and winter, cold air frequently drains off the mountain slopes into the two valleys. This results in airflow toward the north in the San Joaquin Valley and southward in the Sacramento Valley, creat- ing a zone of wind convergence that fluctuates north and south of the delta region according to the relative strength of the airflow out of each valley. The Preliminary Geotechnical Investigation report by J. H. Kleinfelder and Associates states that the site experience means annual precipitation ranging between 14 and 16 inches per year. This information was confirmed by the U.S.G.S. isohyetal map for the region and is based on data collected over a period greater than 60 years. The climate and meteorology of the San Joaquin Valley are unusually conducive for the accumulation of air pollutants. With a high number of sun- shine hours, seasonal inversion conditions, and frequent absence of wind, the Valley has a greater potential for high levels of air pollution then either the Los Angeles or San Francisco Basins. Since the project has no potential to significantly alter the local microclimate or the regional macroclimate just described, no mitigation is deemed necessary. 4-