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Phase II Environmental Site Assessment Manteca Multimodal Station Project Southeast of Moffat Boulevard and Main Street,Manteca, California During the current assessment, VOCs, SVOCs, PCBs,pesticides and herbicides were not detected in any of the soil samples analyzed for those constituents. Varying concentrations of metals were detected in the soil samples collected from 0.5-feet below grade and analyzed for metals. Diesel range TPH(TPH-d) and oil range TPH(TPH-o) were detected in several of the soil samples collected from 0.5-feet below grade. VOCs and gasoline range TPH(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. Resuiis-ivleiais: Varying concentrations of metais were detected in the soil saimpies corrected from 0.5-feet below grade and analyzed for metals. The detected concentrations of metals in soil were compared to the following screening levels or thresholds: USEPA Regional Screening Levels(SLs) California Human Health Screening Levels (CHHSLs), or Total Threshold Limit Concentrations (TTLC). Except for lead,the detected concentrations of metals did not exceed the screening levels or regulatory thresholds to which they were compared. The concentration of lead in RB4 (86.5 milligrams per kilogram [mg/kg]) slightly exceeds the CHHSL for lead in residential soil of 80 mg/kg, but not the commercial/industrial CHHSL for lead of 320 mg/kg. Because the site is proposed for industrial/commercial land uses,the exceedance of the residential CHHSL does not indicate that a health risk to future occupants of the site (commercial/industrial setting) is likely. However, if residential use of the site is planned, further risk assessment of the detected lead in soil in the vicinity of RB4 would be warranted. Lead in Soil Samples RB4 and RB14 (0.5 feet belowrraade): In addition,because the soil samples collected from RB14-0.5' and RB4-0.5' had total lead concentrations that exceeded 50 mg/kg,the soil samples were further analyzed for soluble lead by STLC analysis. Based on the results of the STLC analysis,the 0.5-feet deep sample from RB4 was further analyzed for soluble lead using the toxicity characteristics leaching procedure(TCLP). In addition,the soil samples collected from 2 feet below grade from RB4 and RB 14 were also analyzed for total lead. The results of the STLC analyses for RB4 at 0.5 feet had 11.5 mg/L soluble lead in the soil sample,however,the TCLP result for RB4 was 0.051 mg/L. Because the STLC result exceeds the STLC threshold of 5 mg/L, if soil is excavated from this area, it would be classified as a California Hazardous Waste and would require special handling during excavation and disposal. Note that the sample collected from 2 feet below grade from RB4 had a total lead concentration of 2.38. This concentration is low and would not require special handling. Therefore, if the area of RB4 is to be graded during redevelopment of the site,then, prior to grading, the soil in the vicinity of RB4 (up to 2 feet below grade) should be excavated and disposed offsite at a properly licensed facility. TPI-lin Soil(0.5 feet below graded The concentrations of TPH detected in soil samples collected from the site were compared to environmental screening levels (ESLs) established by the San Francisco Bay Regional Water Quality Control Board(RWQCB). Low concentrations of TPH-d ranging from 3.2 to 35 mg/kg were detected in five soil samples collected at depths of 0.5 feet below grade from beneath the site. Low concentrations of TPH-o ranging from 6 to 82 mg/kg were detected in 14 soil samples collected at depths of 0.5 feet below grade from beneath the site. None of the detected TPH concentrations exceeded the SFBRWQCB ESLs to which they were compared. Because none of the detected TPH concentrations exceeded the SFBRWQCB ESLs, it is reasonable to expect that further investigation or remediation of the TPH detected in soil beneath the site would not be required by a regulatory agency. However, because the San Joaquin County Environmental Health Department(EHD) and the Central Valley RWQCB determine screening levels on a case-by-case basis,we recommend that the City r Rincon Consultants 2