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i The purpose of this work is to evaluate whether a declining trend of fuel contaminants are observed in the soils by sampling in the vicinity of the previously collected soil samples along the former pipeline from the dispenser island and in the former UST excavation areas. i 2.0 Ground Penetrating Radar and Utility Clearance and Aerial Photo Review Aerial photographs from H3W geospatial, Pacific Aerial Surveys (PAS) were purchased and reviewed. PAS Photo AV-2404-44 flown on December 20, 1983 showed the Iocation of the UST ; concrete tank pad, dispenser-island and apparent trench line between the UST and dispenser island. PAS Photo AV-6100-249-41 flown on August 17, 1999 showed the former locations of the UST concrete tank pad, dispenser-island and apparent trench line between the UST and dispenser island. Both photographs were used to measure and create scale distances from a known position (the existing hanger building) to locate the drilling targets indicated by EHD. These target locations were marked upon the existing tarmac and Underground Service Alert (USA)was notified for subsurface utility location. Wright also performed a limited ground penetrating radar geophysical study to confirm target j locations and further investigate and locate the former UST excavation, pipeline trace and island area and assisted in locating other underground utilities that might be in the vicinity of the proposed exploratory borings. The ground penetrating radar geophysical study confirmed the approximate locations of former pipeline and underground storage tank pit. This study was needed since the entire former pipeline and UST area was repaved. The radar work also indicated the location of septic system r features and a storm drain. 3.0 Field Methods--Drilling and Sampling Exploratory Borings Exploratory borings were drilled at the locations shown on Figure. 1. Drilling permits were secured from EHD, and the above referenced underground utility clearance were performed prior to doing the fieldwork. Sample locations were made at locations approximately every 20-feet along the former pipeline to collect soil samples from a depth of 3-feet below the ground surface in native soil (corresponding to the approximately the same pipeline soil sample locations as in 1998). One deep boring (B-6).was advanced in the former UST pit to collect soil and ; groundwater samples. The boreholes were drilled with truck mounted GeoProbe 6600 direct-push drilling equipment. All drilling equipment and sampling tools were cleaned prior to arriving, between each sampling borehole and before leaving the site. The probe collected continuous cores of soil in each borehole. The sampler was then retrieved and dissembled and soil sample intervals retained for chemical analysis were cut from the liners at the desired depths. The soil sample was sealed with Teflon paper or foil and plastic endcaps, labeled, logged onto chain-of-custody forms and placed in a chilled ice chest on crushed ice for transport to the laboratory. Page 2 of 7