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Phase II Environmental Site Assessment Manteca Multimodal Station Project Southeast of Moffat Boulevard and Main Street,Manteca, California of Manteca discuss the results with the San Joaquin County EHD,to confirm that the use of the SFBRWQCB ESLs is acceptable for this site, or to determine a site specific screening level for the TPH in soil beneath the site. TPH and VOCs in Groundwater: VOCs and TPH-g were detected in two of the groundwater samples (B 1 and B3) collected from the soil borings advanced along the southern boundary of the site as follows: • B1-GW: 11 micrograms per liter(µg/L)total xylenes. • B3-GW: 0.6 mg/L TPH-g, 23 µg2 toluene, 58 µg/L ethylbenzene, 159 µg/L total xylenes, and 2,590 Rg/L acetone. The detected concentrations of TPH and VOCs in groundwater were compared to maximum contaminant levels (MCLs) for contaminants in drinking water established by the State of California Public Health(DPH)or to SFBRWQCB ESLs for contaminants in drinking water aquifers. None of the detected VOC and TPH-g concentrations exceeded the MCLs for drinking water or SFBRWQCB ESLs to which they were compared. Because VOCs and TPH were not detected in any of the five foot deep soil samples collected from B 1 through B5, and because groundwater in the vicinity of the site is expected to flow in a northwesterly/northerly direction, it is reasonable to conclude that the TPH and VOC concentrations in groundwater located in the vicinity of B3 and B 1 are originating from an offsite source located hydraulically upgradient(or south/southeast) of the subject site. Furthermore,because none of the detected VOC and TPH-g concentrations exceeded the MCLs or SFBRWQCB ESLs for drinking water, it is reasonable to expect that further investigation or remediation of the groundwater beneath the site would not be required by a regulatory agency. During the redevelopment of the site, the City of Manteca should notify the contractor of the possibility of encountering contaminated soil beneath the site(in the vicinity of RB4 and possibly other areas not identified during this Phase II ESA). Prior to redevelopment of the site, a Soil Management Plan should be prepared to provide guidance for the proper handling, onsite management and disposal of contaminated soil in the vicinity of RB4, and other areas, if encountered, during excavation and grading activities. INTRODUCTION This report presents the results of a Phase II ESA conducted for the property known as the Manteca Multimodal Station Project in Manteca, California(Figure 1, Vicinity Map). The subject site is located to the southeast of the intersection of Moffat Boulevard and S. Main Street and is partially developed with an asphalt-paved bicycle path crossing the site. The remainder of the site is vacant but was historically developed with several warehouses, storage buildings, railroad spurs and a railroad station depot. The following sections provide an overview of the project history; describe the purpose and scope of the project,the physical setting, and sampling and analytical methodologies;provide the results of the sampling and analytical program; and provide conclusions and recommendations. Rincon Consultants 3