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anomalies. On the parcel adjacent to the northeast corner of the intersection only the GPR survey was conducted as subsurface utilities interfered with the VMG survey. The procedures used for the surveys are presented in Appendix C and are summarized below. The VMG survey was conducted using nodes spaced approximately 1.5 meters (5 feet) apart, a grid selected based on the expected size of the target UST. The magnetic field data was reduced in the field and a contour map produced that is referenced to aboveground structures that may affect the results (Appendix Q. Anomalies detected by the VMG surveys potentially created by USTs and other subsurface structures were investigated using GPR. The GPR traverses were spaced approximately five feet apart and oriented both parallel and perpendicular to the anomalies. 2.2.2.2 Soil Sample Collection Based on the results of the geophysical surveys and visual reconnaissance of the parcels, Caltrans selected two boring locations (HP-1 and HP-2)within Caltrans right of way, adjacent to the parcel at the southwest corner of the intersection for investigation of impacts from a potential UST. The borings were advanced to a depth of approximately 6.7 to 7.9 meters (22 to 26 feet) BGS. These borings were logged in general accordance with the Unified Soil Classification System (USCS)by an IT geologist under the supervision of a California-Registered Geologist. Soil samples were collected from 0.1 meters, 0.3 meters, and 0.6 meters (0.3 feet, 1 foot, and 2 feet) BGS for the aerially deposited lead investigation. Soil samples were additionally collected at intervals of 0.6 meters (2 feet) to the terminal depth of the borings. Soil samples from the borings were collected using a 5-centimeter(2-inch) diameter sampler lined with acetate sample sleeves. The soil samples were labeled,packaged, and stored on ice in an insulated chest for transport under chain-of-custody manifest to the laboratory. 2.2.2.3 Groundwater Grab Sample Collection Groundwater grab samples were collected from boring HP-1 and HP-2. Groundwater was generally encountered within approximately 5.6 to 5.8meters (18.5 to 18.9 feet) of the ground surface. After completion of the soil borings, and to facilitate water sampling, a well casing was inserted into the selected soil borings. The casing consisted of approximate 2.5-centimeter(f- inch) diameter, Schedule 40, flush-threaded, 0.05-centimeter(0.020-inch), machine-slotted polyvinyl chloride (PVC)well screen. Dedicated disposable polyethylene bailers were used for sample collection. SncDP-N:IrnncjpllProjeusl82I82I2641ReponII20 Aw in repon.doc 2-3 5127101