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Subsurface Investigation Work Plan SJC Records Retention Center Page 5 bgs) is located approximately 170 feet east-northeast of Site well MW-1,and well MW-10(60-70 feet bgs) is located approximately 95 feet southeast of Site well MW-1. Neither groundwater sample collected from boring B-7 or B-8 contained BTEX constituents or gasoline additives at concentrations exceeding their respective drinking water Maximum Contaminant Levels (MCLs). The most recent groundwater sample collected from well MW-10 (August 2015) contained concentrations of TPH-g at 540 pg/L and benzene at 3.5 µg/L,and toluene,ethylbenzene,and xylenes at very low levels. Based on the non-detect to very low concentrations of dissolved gasoline constituents in groundwater samples collected from HU-2 in borings and/or wells downgradient(northeast, east, and southeast)of the closed-in- place UST at the subject Site,the vertical extent of dissolved gasoline constituents has been defined and no additional investigation is warranted. 4.2 SHALLOW SOIL BORING SAMPLING Analytical results of soil samples collected at depths of approximately 8 and 10 feet bgs directly beneath the closed-in-place UST contained no detectable concentrations of petroleum hydrocarbon constituents. However, shallow soil samples from 0 to 5 feet bgs have not been collected. Condor will collect shallow soil samples from two locations near the closed-in-place UST at depths of approximately 4.5-5.0 feet bgs with a hand auger. Boring HA3 will be advanced approximately 2 feet north of the UST, and boring HA2 will be advanced slightly farther(approximately 7 feet west) from the UST in native soil just outside the area of fill. Laboratory analytical results of the shallow soil samples will be compared to screening criteria in accordance with in the State Water Resources Control Board's Low-Threat Underground Storage Tank Closure Policy(LTCP).Figure 5 in Appendix A presents the locations of the proposed shallow soil borings. 4.2.1 Site Preparation The proposed soil borings will be marked with white paint and Underground Service Alert(USA)will be notified so that utilities can be located and marked at least 48 hours prior to drilling and sampling. Condor will prepare any required permit applications for submittal to EHD prior to scheduling the work. 4.2.2 Fieldwork Preparation Prior to commencement of fieldwork, a tailgate safety meeting will be held and a site-specific Health and Safety Plan will be discussed with,and presented to,all field personnel for their signatures. 4.2.3 Field Procedures Drilling activities will be performed under the supervision of a Condor Professional Geologist in accordance with the provisions of the EHD permits.Descriptions of soil types encountered will be recorded on geologic logs. After cutting or breaking through the surface asphalt, the soil borings will be advanced by hollow stem auger to the desired depth. Soil samples will be collected at a depth of approximately 4.5 feet bgs using a slide hammer lined with a 2-inch diameter brass or stainless-steel sampling tube. The soil samples will be capped at each end with Teflon®tape and plastic end caps, labeled, and placed in a pre-cooled ice chest. The soil samples will be transported under chain-of-custody protocol to a state-certified analytical laboratory for analysis. The drill cuttings will be screened in the field with a photoionization detector (PID) for the presence of volatile organic compounds. If PID readings are less than 20 parts per million(ppm),then the cuttings will be placed back into each borehole and lightly wetted to facilitate compaction. The ground surface at each borehole will be restored by applying cold patch concrete. If PID readings of soil cuttings exceed 20 ppm, then the cuttings will be placed in an appropriate sealed container and will remain on Site pending the ILO CONDOR