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The borings were logged by a Professional Geologist using Unified Soil Classification System(USCS) <br /> descriptions. Soil samples were observed for indications of hazardous materials or petroleum products <br /> (e.g., soil discoloration or "chemical' odor). Each soil sample was screened with a photo-ionization <br /> detector (PID) for preliminary indications of volatile organic compounds (VOCs). Soil collected for <br /> screening purposes was placed in new re-sealable plastic bags to facilitate using the PID to screen the <br /> sample for VOCs within the bag "headspace." A hand-held global positioning system (GPS) receiver <br /> was used to determine the latitude/longitude coordinates of the boring locations. The boring <br /> coordinates are summarized on Table 1. <br /> The borings were backfilled with bentonite slurry to a depth of 3 feet,then with soil cuttings to near the <br /> surface and patched with cold-patch asphalt. The boring grouting activities were observed by a <br /> representative of SJCEHD. <br /> Quality Assurance/Quality Control Procedures <br /> Quality assurance/quality control (QA/QC) procedures were performed during the soil sampling <br /> activities. These procedures included decontamination of sampling equipment prior to and between <br /> each borehole location and providing COC documentation for each soil sample submitted to the <br /> laboratory. The soil sampling equipment was cleansed by washing the equipment with an Alconox® <br /> solution followed by a double rinse with deionized water. <br /> Laboratory Analyses <br /> Soil Samples <br /> Soil samples were selected for analysis based on field observations and soil screening results, sample <br /> locations/depths, and the experience and judgment of the field geologist. Soil samples collected from <br /> depths of 5 and 10 feet from each boring were analyzed under standard ten-day turnaround time by <br /> ATL for the following: <br /> • Four soil samples were analyzed for gasoline-range organics(GRO),diesel(DRO),and oil (ORO) <br /> following United States Environmental Protection Agency(EPA)Test Method 8O15B(M). <br /> • Two soil samples were analyzed for VOCs following EPA Test Method 826013, semi-volatile <br /> organic compounds(SVOCs)following EPA Test Method 827OC,and polychlorinated biphenyls <br /> (PCBs)following EPA Test Method 8082. <br /> • Two soil samples were analyzed for Title 22 metals following EPA Test Methods 6010B and <br /> 7471A(mercury). <br /> Laboratory QA/QC Procedures <br /> QA/QC procedures were performed by ATL for each method of analysis with specificity for each <br /> analyte listed in the test method's QA/QC. QA/QC measures as applicable will include the following: <br /> • One method blank for every ten samples, batch of samples or type of matrix, whichever is more <br /> frequent. <br /> • One sample analyzed in duplicate for every ten samples, batch of samples or type of matrix, <br /> whichever is more frequent. <br /> Linden UST Site Investigation,TO No.4 Caltrans Contract 06A1895,EA No.1O-OY3600 <br /> Geocon Project No.S9800-01-04 -3- December 11,2013 <br />