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`�u vf9 <br /> m <br /> exg <br /> 2.2 Subsurface Investigation <br /> 2.2.1 Geophysical Survey <br /> On November 11, 2008, NORCAL, under supervision by Bureau Veritas, conducted a geophysical <br /> survey of the former on-site filling/service station location, as depicted on fire insurance maps <br /> reviewed by Bureau Veritas during the 2008 Phase I ESA. An area measuring approximately 75 <br /> feet by 75 feet in the southeastern corner of the subject property was surveyed in grid patterns to <br /> evaluate for anomalies indicative of abandoned USTs, hydraulic equipment, and other subsurface <br /> appurtenances related to the former on-site filling/service station. The geophysical survey <br /> included the use of metal detection equipment(MAG)and ground penetrating radar(GPR). The <br /> survey located numerous subsurface utilities, electric lines, storm drain lines and other utilities; <br /> however, no unidentified suspect features and/or buried metallic anomalies were identified that <br /> are indicative of filling/service station equipment or USTs. A copy of the NORCAL Geophysical <br /> Investigation, dated November 25, 2008, is presented in Appendix B. <br /> 2.2.2 Soil Borings <br /> Upon clearance of utilities, Bureau Veritas contracted with EnProb Environmental Probing <br /> (EnProb)of Oroville, California to provide drilling services at the subject property. EnProb is a <br /> California licensed C-57 driller and advanced six borings(BV-1 through BV-6)on November 19 <br /> and 24, 2008 under supervision by Bureau Veritas at the subject property using truck-mounted <br /> direct-push equipment. The borings were advanced to maximum depths that ranged from 12 feet <br /> to 36 feet below ground surface(bgs). Boring depths were selected to attempt to obtain grab- <br /> groundwater samples at each location. Borings BV-1 through BV-4 were advanced to total depths <br /> between 35 and 36 feet bgs. Boring BV-5 was advanced to a depth of 30 feet bgs to collect a <br /> grab-groundwater sample since this boring was located on the truck ramp,which had a lower <br /> elevation than the other boring locations. Boring BV-6 was terminated at a total depth of 12 feet <br /> bgs due to discussions with USAN utility locators that revealed two drinking water supply lines <br /> were located in the immediate area and the precise locations were not known (Note: typical water <br /> supply lines are constructed of cementaceous pipe that are not readily located using geophysical <br /> equipment). The locations of the borings completed as part of this investigation are presented in <br /> Figure 2. <br /> A summary rationale of the soil boring locations (Figure 2)is provided in the following table. <br /> IDENTIFIED RECs SOIL <br /> BORINGS <br /> Historical on-site filling/service station&adjoining upgradient dry cleaners <br /> Former service station building location, approximate BV-1 <br /> Former service station fueling island location, approximate BV-2 <br /> SE comer of subject property nearest to adjoining cross-gradient service station BV-3 <br /> South, upgradient property boundary near former on-site service station BV-4 <br /> South, upgradient property boundary(loading ramp)near adjoining dry cleaners BV-5 <br /> SW, upgradient comer of subject property near adjoining dry cleaners BV-6 <br /> The soil borings were advanced to evaluate the potential for soil contamination at each location in <br /> proximity to the identified RECs. <br /> 3 Project Number 99008-008321.03 <br />