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} Site Background Information: Five Star Marina Page 3 of 4 while diesel-impacted water was documented along the western edge of the property boundary. In January 1998, four ground water monitoring wells were installed near the West UST area to quantify the hydrocarbon concentration in ground water and determine the direction of ground water flow.Results of the well installation and subsequent sampling delineated the dissolved hydrocarbons and indicated direction of ground water flow to be generally toward the northeast. Ground water monitoring enabled delineation of the dissolved hydrocarbon plume,with concern for the possible migration of the plume away from the West UST area. On 18 January 2001,the west UST location was over-excavated to depths as great as 15 feet bsg to remove petroleum hydrocarbon-impacted soil. Soil samples were collected from each wall of the excavation between 12 feet and 13 feet bsg and from the soil stockpiles and analyzed for petroleum hydrocarbon constituents. No contamination was reported in the wall samples. TPH-g and BTEX were reported in the stockpile samples at concentrations as high as 2,600 mg/kg TPH-g, 3.8 mg/kg benzene, 76 mg/kg toluene, 58 mg/kg ethylbenzene, and 350 mg/kg xylenes (Table Al). The destruction of monitoring well MW-UST was performed on 15 February 2005 by Mitchell Drilling Environmental of Rancho Cordova, California under EHD oversight. As per verbal instructions given in the field by EHD personnel,well destruction activities were performed utilizing a CME-75HT truck-mounted drill rig to pull approximately one-half of the well casing out of the 15-foot boring. The boring, with the remaining portion of the well casing in place, was backfilled to surface grade with type I/II portland cement. PART II UNDERGROUND STORAGE TANK REMOVAL In 1997, during investigation of a gasoline underground storage tank (UST) at former Stephen's Marine (also known as Five Star Marina) a second UST was discovered. The UST was located in Lindsay Street, between the northern and southern blocks of on-site buildings. On 18 November 1997, the 4,000-gallon gasoline UST was removed from the site. Upon removal of the UST, holes were noted at the western end and in the bottom of the UST. Hydrocarbon odors were not observed in soil above 11 feet bsg.Approximately 5 cubic yards of hydrocarbon-impacted soil were removed and stockpiled during the UST excavation. Soil samples were collected 2 feet below the UST, at depths of 12 feet bsg.The overburden soil was used to backfill the lowest portion of the excavation. Advanced GeoEnvironmental,Inc.