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(V:V V(: 0 A S S O C I A T E S I N C excavated to c% maximum depth of approximately 13 feet below ground surface (bgs) During the excavation, soil samples were collected at various depths from the bucket of the backhoe Using hand tools, 6-inch brass soil sampling sleeves were driven into soil in the backhoe bucket and once retrieved, the sleeve ends were capped with Teflon sheets and plastic end caps Additionally, small amounts of soil from the backhoe bucket were placed in zip-lock bags and field screened utilizing a Photoionization Detection Meter (PID) to quantity volatile organic vapors present, if any PID readings from Trench 1 ranged from 2 parts per million (ppm) at 2 5 feet bgs, to 154 ppm at 12 5 feet bgs A second test trench (Trench 2) was excavated near the intersection of Thornton Road and Stockton Street, located approximately 240 feet northwest of 26080 Thornton Avenue This trench was excavated to a depth of approximately 12 feet bgs Soil samples were collected and field screened in the manner described above PID measurements of soil collected from the second trench did not exceed the background ambient concentration of 0 ppm Test trench locations are shown on Figure 2 Field notes, including PID measurements collected by ATC's technician, are included in Attachment 1 Collected soil samples were placed on ice and transported under chain-of-custody to State- certified American Environmental Network, Inc 's (AEN's) laboratory Samples were analyzed for benzene, toluene, ethylbenzene, and xylenes (BTEX) by EPA method 8020 and total petroleum hydrocarbons as gasoline (TPHg) by EPA method modified 8015 Laboratory analyses did not detect any of the tested constituents at or above laboratory method detection levels The method detection levels for BTEX and TPHg were 0 005 and 0 2 ppm, respectively At the request of ATC, the laboratory confirmed the results and soil sample GP-T1- 10' was tested twice Laboratory results remained nondetect Analytical results are summarized in Table 1 Laboratory reports and chain-of-custody documentation are presented in Attachment 2 In conclusion, the apparent petroleum impacted soil, as indicated by visual observations and PID readings, was observed in Trench 1 but not in Trench 2 located at distances of approximately 950 feet and 240 feet from the subject property, respectively This would indicate the apparent contamination in Trench 1 is most-likely from a source other than former USTs at 26080 Thornton Avenue Additionally, even though soil samples analyzed by the laboratory did not exhibit the presence of BTEX or TPHg, field observations and PID measurements indicate soil contamination may be present in the vicinity of Trench i and therefore this area warrants additional investigation Future analysis of soil samples collected in this area, if performed, should probably be analyzed utilizing more encompassing DOHS LUST laboratory tests (such as a full hydrocarbon screen) and/or EPA methods 8240/8260 for volatile organic compounds w 1943261rgMrt9�SLO1_&aM doc 2