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Draft Limited Phase II Site Investigation <br /> Austin Road-SR 99 Van Till Property Acquisition BCI File No. 2643.x <br /> Manteca California October 23, 2013 <br /> INVESTIGATIVE SUMMARY <br /> Blackburn Consulting(BCI)prepared this Limited Phase II Site Investigation(PSI) for the Austin <br /> Road—SR99 Van Till Property Acquisition project located in Manteca, CA. This PSI is based on <br /> the direction provided by Caltrans via email of September 19, 2013 and subsequently revised on <br /> September 23,2013. The PSI is designed to address hazardous material issues that can affect <br /> project planning, design, and/or Caltrans right-of-way (ROW)acquisition requirements. <br /> The PSI requirements outlined by Caltrans include: <br /> 1) Pesticide and heavy metals screening of soils within the upper two feet; <br /> 2) Aerially Deposited Lead(ADL) assessment in the upper two feet of soil; and <br /> 3) Total Petroleum Hydrocarbon(TPH) screening in groundwater or soil at 25 feet below <br /> ground surface (bgs). <br /> Conclusions and Recommendations <br /> 1. Pesticide/Heavy Metals Screening <br /> The purpose of the assessment was to evaluate the parcel for residues of persistent pesticides and <br /> associated heavy metals. The pesticide screening focused on common historically-used <br /> organochlorine pesticides(OCPs) and heavy metals which have been found to be persistent in <br /> the environment. <br /> Conclusions: OCPs were not detected. Heavy metal concentrations are consistent with <br /> background levels. We conclude that no further assessment is warranted for the pesticides <br /> and/or heavy metals evaluated in this report. <br /> 2. Aerially Deposited Lead(ADL) <br /> Aerially Deposited Lead(ADL) has been found to occur in soils adjacent to highways. The lead is <br /> presumably from the historical use of leaded gasoline and subsequent exhaust emissions. The <br /> presence of ADL is generally limited to the upper twenty-four(24) inches of the unpaved shoulder <br /> and median areas. <br /> Conclusions: ADL screening results do not indicate the presence of elevated lead levels; <br /> consequently we conclude that no further ADL assessment is warranted. <br /> 3. Total Petroleum Hydrocarbons (TPH) <br /> Caltrans requested screening for petroleum hydrocarbons in the subsurface at a depth of 25 feet <br /> below ground surface (bgs). <br /> Recommendations: TPH was not detected in our soil sample obtained at 25 feet bgs. We <br /> conclude that no further assessment is warranted for TPH. <br /> i <br />