SU0011532 SSCRPT - Laserfiche WebLink

Home Browse Search

Phase I Environmental Site Assessment 1��rracon Proposed CarMax Automotive Dealership ■ Stockton, CA August 8, 2015 ■ Terracon Project No. NA157024 7.1.4 Historical Records Based on a review of the historical information, the site was used for row crops and an orchard from the late 1930s through the mid-2000s. The surrounding properties consisted of row crops and orchards through the 1990s, when the properties to the west were developed with the existing commercial development. Based on Terracon's review of the historical records, VECs were not identified in connection with the site or adjoining properties. 7.1.5 Regulatory Records Terracon reviewed the regulatory database (see Section 4.0) for facilities potentially utilizing petroleum hydrocarbons within one-tenth of a mile of the site and facilities potentially using other volatile chemicals of concern within one-third of a mile of the site. Based on Terracon's review of the regulatory records, Terracon did identify potential facilities of concern. Based on Terracon's review of the regulatory records, VECs were not identified. 7.1.6 Physical Setting Characteristics According to a Preliminary Geologic Map Showing Quaternary Deposits of the Lodi Quadrangle, California by D.E. Marchand and B.F. Atwater 1979, the site is located within the Modesto Formation Upper and Lower Members (Qm,). According to Atwater, the Modesto Formation is characterized by no stipple to dense stipple sands and silts deposited in the Pleistocene age. Shallow soils are identified by the Natural Resource Conservation Service (NRCS) as Stockton clay. The depth to groundwater is estimated by the California Department of Water Resources, Spring 2014 to be approximately 60 to 62 feet bgs, and the regional direction of ground waterflow is estimated to be toward the northeast. The northern and eastern adjoining streets followed by vacant lots are considered to be up- gradient of the site, the southern adjoining walnut orchard is considered to be down gradient of the site, and the western adjoining commercial facilities are considered to be cross to down gradient of the site. 7.1.7 Natural or Man-made Conduits The site is located in a developed area of the city containing utilities along the adjacent rights of way. Based on the absence of potential identified vapor sources in the site vicinity it is unlikely that man-made conduits, such as utility corridors, provide a potential path for vapor migration. Additionally, natural conduits, such as karst terrain/features, are not known to exist in the site vicinity. 7.1.8 Conclusions Based on the physical setting of the site, the current use of the site and the findings from the historical and regulatory records review, VECs are not likely to exist at the site. Responsive ■ Resourceful ■ Reliable 16