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Review of the analytical data for analyzed soil and groundwater samples indicates the following: • Laboratory analysis of soil samples identified various metals in soil samples collected from the site and analyzed, including; arsenic, barium, cadmium, chromium, lead, mercury, and selenium. With the exception of arsenic, the reported metal concentrations were below the regulatory RSLs and comparative ESLs. The concentrations of arsenic in the analyzed soil samples from Borings B-1,B-2,B-5,B-6,B-7,B-8, B-9, and B-10 ranged from 0.87 to 4.7 milligrams per kilogram(mg/kg). The specific concentrations of each sample are noted in Table 1 of this report. The identified concentrations of arsenic in soil samples from the site were compared to reported background levels of arsenic in soil across California as stated in Element Concentration in Soils and Other Surficial Materials of the Conterminous United State written by Hansford T. Shacklette and Josephine G. Boerngen. Background levels for arsenic in the general area were reported in this document at a mean concentration of 5.5 mg/kg with an observed range of <0.10 to 97 mg/kg. The reported concentrations of arsenic in soil samples from the site are below the reported mean concentration of Shacklette and Boerngen and within reported background levels. In addition, the concentrations of arsenic in the soil samples from various locations across the site appeared to be more or less consistent horizontally as well as vertically without significant variation suggestive a lack of potential contaminant source(s) or primary area(s) of concern. Additionally,the majority of the subject property is covered by buildings, concrete foundations, and/or asphalt, which generally serves as a confining cap and preventing direct exposure. As such, arsenic in the soil samples from the site appeared to be within background concentrations and relatively immobile in the subsurface due to the presence of a confining cap over most of the site, which also prevents direct contact and exposure to soils at the site. • Analysis of soil samples identified concentrations of TPH-DRO at 1.9 mg/kg in B-3A; 3.5 mg/kg in B-5A; 1.2 mg/kg in B-5B; and 3.2 in B-7A. The detected concentrations of TPH-DRO were reported at concentrations below the comparative ESL of 110 mg/kg for industrial sites where groundwater is a current or potential source of drinking water. The RSLs do not include a regulatory level for TPH- DRO but reference a level of 3.1 mg/kg for Total Petroleum Hydrocarbons — Aliphatic Medium Range and 63 mg/kg for Total Petroleum Hydrocarbons—Aromatic Medium Range. • The reported concentrations of OCPs and VOCs in soil samples collected from the site and analyzed were below the laboratory limit of detection(LLD). • Laboratory analysis of groundwater samples collected from the site and analyzed identified TPH- DRO in borings B-1 W at 70 micrograms per liter (µg/L); B-2W at 270 µg/L; and B-7W at 58 µg/L. The RSLs do not currently have a regulatory level for TPH-DRO in groundwater; however, the reported concentration of TPH-DRO in the groundwater sample B-2W was above the referenced ESL of 100 pg/L. • Analysis of the groundwater samples collected from the subject property and analyzed identified chloroform in B-4W at 0.70 µg/L. The reported concentration of chloroform in boring B-4 is below the regulatory RSL of 80µgJL and below the referenced ESL of 170 µg/L. No other concentrations of VOCs were found above the LLD in any of the groundwater samples collected from the site and analyzed. Zions First National Bank Limited Subsurface Investigation 10 f�UCII� Valentine Properties—Manteca, California a rr