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Page 3 Cabral—Mc Adams Property April 28,2006 Job No. 1828-092.01 SOILS AND GROUNDWATER The subsurface soil conditions encountered in our borings at the subject property are relatively uniform. Surface soils to our maximum 40 foot depth of exploration generally consist of tan silty sands/sandy silts, brown to red-brown fine sands, and red-brown slightly silty sands. Backfill materials comprised of brown silty fine sands with gravel were encountered to a depth of approximately eight feet in two of the borings(Boring B 1 and 132). Groundwater was not encountered within a depth of 40 feet in our borings performed in October 2005 and March 2006. Historically, the groundwater gradient in the Stockton area has been westerly from the Sierra Nevada toward the center of the Valley. Groundwater elevation data for the past decade obtained from the San Joaquin County Flood Control and Water Conservation District mapping indicates that the groundwater gradient in the general site vicinity trends northerly toward a large regional cone of depression. The mapping indicates that shallow groundwater typically is encountered within about 50 feet of ground surfaces within the vicinity of the subject property. Communications with a property owner representative, Mr. Steve Mc Adams, indicates that groundwater beneath the subject property may be on the order of about 70 feet. Depending upon seasonal groundwater recharge, the proximity to surface water courses and nearby pumping, localized variations in the depth and flow direction are likely. EXPLORATION AND SAMPLING ACTIVITIES General All drilling and sampling activities were overseen by a Professional Geologist from our office. The locations of our soil borings are shown on Plate 2, Plot Plan. Prior to drilling activities, we obtained the necessary drilling permits through the San Joaquin County Environmental Health Department (SJCEHD). We contacted Underground Service Alert to clear the boring locations of underground utilities. Additionally, we directed a geophysical survey to further clear the boring locations. Continuous soil sampling was performed in each of the seven borings using a track-mounted direct push drill rig. All boring and sampling equipment was pre-cleaned prior to arrival and thoroughly cleansed between each sampling event. A new pair of disposable nitrile gloves was worn during and between soil sampling activities. Soil samples were collected in laboratory- approved plastic sleeves that were sealed with Teflon tape and plastic end caps. Each soil sample collected was labeled and placed on ice immediately following sampling. The soil samples were delivered to a State-certified chemical laboratory under chain-of-custody for analysis. Following the drilling and sampling activities, each boring was completely backfilled with neat-cement grout, in accord with SJCEHD requirements. Labeled wooden lath or plastic markers were set at each boring location so that the locations could be identified at a later date if necessary.