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2.4 Surface Water Hydrology The subject property was located within the San Joaquin River drainage, which encompasses roughly 15,000 square miles of the San Joaquin Valley to the south of the Sacramento-San Joaquin River Delta and north of the Tulare Lake Basin. Principal tributaries to the San Joaquin River include the Consumnes River,Mokelumne River, Tuolumne River, Calaveras River, Stanislaus River, Merced River, Chowchilla River, and Fresno River. The subject property is situated about five miles east of the San Joaquin River about and about seven miles north of the Stanislaus River, a tributary to the San Joaquin River. Local drainage patterns have been altered by development of a network of aqueducts, main and lateral canals, and irrigation ditches to support commercial agriculture. The surface hydrology of the site and site vicinity has been altered by urban development. Surface water at the site would flow generally westerly, but would be directed to storm drains associated with the municipal storm water management system. 2.5 Groundwater Hydrology The site is situated within the Eastern San Joaquin Subbasin of the larger San Joaquin Valley Groundwater Basin, which lies between Mokelumne River and the Stanislaus River and bounded on the west by the San Joaquin River and on the east by the bedrock of the Sierra Nevada Range. The Eastern San Joaquin Subbasin is comprised of unconsolidated continental deposits, alluvium, flood-basin deposits, and lacustrine and marsh deposits with cumulative thicknesses of a few tens to a few hundreds of feet. Water-bearing formations of significance in the Eastern San Joaquin Subbasin consist of the alluvium and Modesto/Riverbank Formations, flood basin deposits, Laguna Formation, and Mehrten Formation. Shallow groundwater is generally unconfined and semi-confined. Shallow groundwater in the site vicinity has been encountered by others at depths ranging from 20 to 30 feet below ground surface (bgs). Groundwater gradient in the site vicinity is estimated to be westerly following topography. 3.0 FIELD INVESTIGATION On 28- and 29-Jan-2014, seven direct-push soil borings and three hand-augur borings were advanced at the site. Prior to conducting field investigation activities, the presence of underground utilities was further inspected and marked. The site was cleared for underground utilities by DigAlert of Northern California. Ms. Eve Dunn and Mr. Wes Dewsnup of EarthTouch, Inc., performed soil logging, sample collecting, and boring abandonment activities. At each location the soil samples were collected using a direct-push drill rig operated by Cascade Drilling, LP of Richmond, California or utilizing a concrete cutting machine and a stainless steel hand auger. Mr. Johnny Yoakum of the San Joaquin County Environmental Health Department (EHD) was present on subject property for the first part of the field investigation and following drilling activities to oversee the grouting and sealing of the borings. 3.1 Direct-Push Soil Borings and Sampling Borings were advanced up to 24 feet bgs. Soil samples were continuously collected using a stainless-steel hand auger and/or a 2-inch diameter sampling probe edged with disposable liners driven through the subsurface by hydraulic hammer. Soil samples were collected in the disposable liners in 4-foot intervals, which were then removed from the probe and opened for inspection. Collected soil samples were physically inspected, logged, and examined for visual and olfactory evidence of impact. Groundwater was collected using new, dedicated,polyethylene tubing and a peristaltic pump. Zions First National Bank Limited Subsurface Investigation 7 flUC�lk Valentine Properties—Manteca, California W"7='m