Laserfiche WebLink
i <br /> source of water throughout the area (Hotchkiss and Balding, 1971) . <br /> Regional groundwater is divided into three water-bearing zones: a lower, <br /> confined zone below the Corcoran Clay Member; a confined zone above the <br /> Corcoran Clay Member; and a shallow, unconfined zone within 25 feet of the <br /> ground surface. The lower two water-bearing zones are the primary sources <br /> of groundwater in the Tracy area (Hotchkiss and Balding, 1971) . <br /> The groundwater quality in the Tracy area is degraded by the intrusion of <br /> saline, connate groundwater as a result of overdraft of deeper aquifers in <br /> the Stockton and Tracy areas. Shallow groundwater is generally of poor <br /> quality along the western boundary of the San Joaquin Groundwater Basin <br /> (DWR, 1975) . Water samples collected from observation wells installed <br /> onsite showed typical conductivity levels of 3000 microsiemens per <br /> centimeter, indicating a relatively high concentration of dissolved salts in <br /> the uppermost aquifer. <br /> 3286a/BAV100 10 <br />