SITE INFORMATION AND CORRESPONDENCE_FILE 1

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There are several formations bearing ground water, but fresh water occurs only in part of them. A generalized stratigraphic cross-section of San Joaquin County with water-bearing characteristics is represented in Table 1 . The surface of the Central Valley is composed of unconsolidated Pleistocene to recent sediments in the form of clay, sand, silt, _ gravel, poorly cemented and poorly sorted, almost entirely alluvial-fan and lacustrine in origin and of maximum thickness of 8 , 000-10, 000 feet . The immediate stratigraphy beneath the site consists of silt and silty clay from the surface, between 12 and 17 feet thick. Below this there is a layer of silty or clayey sand 3-8 feet thick. Below the sandy bed, to the explored depth of 32 . 5 feet, there is stiff silty or sandy clay more than 5 feet — thick. At one location, MW7, a second lens of sand was found at 27-29 feet (Appendix A) . — 1 . 3 WATER USE AND WELL INVENTORY Information was collected on all private and public wells located within a 1 -mile radius of the site. There appear to be four wells within 1 /2 mile of the site and 10 within 1 mile. Figure 1 shows the locations of all wells within 1 /2 and 1 -mile radius — that are in the inventory of the California Department of Water Resources in Sacramento. EA is not aware of any well located — downgradient of the site within a 1 -mile radius that pumps water either from within the shallow (perched ) water or from the deeper water-bearing zone. The closest well, designated as C, located at a distance of about 2, 000 feet ( at the intersection of Manchester and Brookside streets ) is 535 feet deep, with perforation starting at 149 feet below the surface. All remaining wells are at least 345 feet deep, with perforation — starting deeper than 144 feet. No wells are located in the apparent downgradient direction from the site, and all except well C are located on the southern side 4