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Groundwater in the region occurs in three water-bearing zones. These include the lower zone, which contains confined fresh water in the lower section of the Tulare Formation, an upper zone which contains confined, semi-confined, and unconfined water in the upper section of the Tulare Formation and younger deposits,and a shallow zone which contains semi-confined and unconfined water to within about 25 feet of the land surface. Historically, groundwater flow was northwestward parallel to the San Joaquin River. More recent data shows flow tending northeastward, toward the San Joaquin River. The groundwater flow direction towards the San Joaquin River typically causes subsurface outflow laterally along the eastern boundary of the San Joaquin Valley. The hydraulic gradients west of the San Joaquin River are generally steeper than those east of the river. Typically, notwithstanding local influences, the water table west of the San Joaquin River can be thought of as a subdued replica of the ground surface topography, sloping gently toward the river from the Coast Ranges. Based on borings advanced during the January 13, 2015 investigation, the underlying subsurface consists predominantly of brown,dense,damp clay with some medium sand(CL)from the ground surface to approximately 10 feet bgs. At 10 feet bgs, the subsurface consists predominantly of brown and red, well-graded wet gravels (GW) or fine to medium grained silty sand (SM). Groundwater was encountered during this investigation at approximately 10 feet bgs. Groundwater was also encountered at approximately 10 feet bgs during the May 21,2015 groundwater sampling. The May 21, 2015 borings encountered brown, dense silty sand (ML) to approximately 10 feet bgs; medium grained silty sand (SP) was encountered below 10 feet bgs. Based on review of the State Water Resources Control Board GeoTracker database, a leaking underground storage tank (LUST) site is located at 3425 North Tracy Boulevard located approximately 630 feet north of the Quality Cleaners. A January 20, 2005 report prepared by URS Corporation Americas on behalf of the Atlantic Richfield Company contained site specific groundwater analytical data and groundwater gradient data from 1988 to December 2004. The groundwater gradient was variable however, the predominant groundwater gradient was to the northeast typically at 0.004 feet per foot. This report includes groundwater analytical data from a monitoring well (ATR-10) located within the sidewalk immediately north of the property with the address of 3379 North Tracy Boulevard which is adjacent to the northeast Site boundary and currently occupied by a vacant Long John Silver's restaurant. Well ATR-10 was sampled from 1990 to 2004 and the groundwater samples did not contain detectable gasoline constituents with the exception of a trace detection of toluene in one sample. Currently, there are no documents within GeoTracker with descriptions or depictions of stratigraphy associated with this site. Based on review of GeoTracker, the following language was excerpted from an April 26, 2007 report prepared by Conestoga-Rovers&Associates regarding the Shell-branded LUST site located Sampling and Analysis Workplan Tracy Corners Shopping Center 3225 North Tracy Boulevard Tracy,California 95376 Partner Project Number SM14-129814 Docket Number HAS-VCA 14/15-108 August 15,2016 Page 13