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Partner completed a Phase II investigation for the Quality Cleaners to investigate the potential impact of PCE and related chlorinated volatile organic compounds in sub-slab soil gas as a consequence of a potential release from the dry cleaning facility. The work was summarized in Partner's December 19, 2014 report. The scope of the Phase II Investigation included the installation of four sub-slab soil gas probe samples (SG1 through SG4) and analysis of four samples and one duplicate sample for PCE,TCE, cis-1,2-dichloroethene(cis-1,2-DCE),trans-1,2- dichloroethene (trans-1,2-DCE), and vinyl chloride. Soil gas analytical results are summarized in Table 1 and sample locations are shown on Figure 3. PCE was detected in the four sub-slab soil gas sample and one duplicate sample. The maximum concentration of PCE was 3,300 µg/m3; one sample (and the duplicate sample) contained TCE at a maximum concentration of 350 µg/m3. Soil gas data was used to calculate theoretical indoor air concentrations using the DTSC recommended foundation attenuation factor of 0.05. The calculated theoretical indoor air concentration of PCE was 165 µg/m3 and of TCE was 17.5 µg/m3. The calculated theoretical indoor air concentrations indicate PCE and TCE could be greater than the DTSC Commercial/Industrial land use screening level for PCE of 2.08 µg/m3 in the four samples and greater than the EPA Industrial Air Regional Screening Level (RSL) for TCE of 3.0 µg/m3 in one sample. As noted above,the calculated indoor air concentration of TCE exceeds the DTSC's August 23, 2014 Accelerated Response Action level of 8 µg/m3 (based on an 8-hour workday). Due to the presence of PCE and TCE in sub-slab soil gas samples, Partner recommended soil and groundwater be sampled to further assess the PCE and TCE at the Site. Specifically, on January 13, 2015, four soil borings (B 1 through 134) were advanced to the south of the dry cleaning machine, which was the anticipated hydraulically upgradient location relative to the dry cleaners. As summarized in Partner's January 27, 2015 report, three of the groundwater samples contained PCE, the greatest concentration at 30 µg/L from boring B3 located approximately 100 feet southwest of the dry cleaners machine location. Partner's field personnel discerned that it was possible that the sewer lateral associated with the dry cleaner was to the southern exterior of the dry cleaners suite.As noted above,the sewer lateral was not located south of the dry cleaners suite. Soil samples were collected at 10 feet below ground surface (bgs) in each of the four January 13, 2015 borings and analyzed for PCE, TCE, cis-and trans-1,2-DCE, and vinyl chloride; no target VOCs were detected above the laboratory reporting limits (RLs). Sample analytical results are summarized in Tables 2 and 3 and sample locations are shown on Figure 3. On May 21, 2015, Partner conducted an expedited Site characterization activity as part of due diligence for the Loja. The boring locations were selected with the concurrence of Loja's environmental consultant,Roux Associates, Inc. The assessment included eight grab groundwater 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 5