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Site Background Information: Former Curtiss Pontiac-Buick AGE-NC Project No. 96-0254 Page 5 of 7 • TPH-g, TPH-d and BT EX compo unds were de tected on ly in t he water sam ple collected from CPT-2 (61 to 65 feet bsg), at concentrations of 110pg/i TPH-g, 85 pg/I TPH-d, 2.4 pg/I benzene, 3.3 pg/I toluene, 1.3 pg/I ethylbenzene and 5.9 pg/I total xylenes. Laboratory analysis of grab ground water samples collected from CPT-1 at depths of 26 feet to 30 feet, did not report any of the analytes at or above laboratory reporting limits. Fuel oxygenated compounds were not detected in the ground water samples. On 22 May 2003, monitoring wells MW-4, MW-7 and MW-1A/B (dual completed well) were destroyed as pad of oyer-excavation activities b remove hydrocarbon-impacted soil related to an unauthorized release of petroleum hydrocarbons from former USTs at the site. The wells were destroyed by over-drilling thewells to total depth and then backfilling them with portland cement to approximately 8 feet bsg and be ntonite from 8 feet bsg to surfa ce grade. On 30 June 2003, monitoring wells MW-1A, MW-1 B, MW-4 and MW-7 were re-installed as single completed wells. P ilot bo rings M W-1 B and MW-4 w ere adv anced to approximately 15 feet bsg; pi lot bor ings M WAA and MW-7 w ere adv anced to approximately 28 feet bsg and 41 feet bsg, respectively. No soil samples were collected during the well reinstallations. A ground water monitoring program has been conducted at the site since February 1998 to present. The I ateral and vertical extent of impac ted s oil and t he I ateral extent of impacted shallow ground water at the site have been defined in all directions. The vertical extent of dee per imp acted g round w ater has bee n de fined tow and the north a nd is generally defined in the southern portion of the site. IMPACTED SOIL REMOVAL ACTION From 28 to 30 May 2003, over-excavation of the former gasoline UST excavation was conducted by Valued Engineering of Stockton, utilizing a backhoe. Soil was excavated to an approximate depth of 8 feet bsg at the former gasoline UST area. Excavated soil was screened for the presence of organic vapor using an OVM and the soil was segregated into impacted and clean soil based on the OVM results. The dean soil was used to backfill the excavation and the impacted soil was stockpiled for disposal. Soil samples were collected from intermediate depths within the pit during excavation and from the floor and sidewalls of the pit at the conclusion of excavation activities. Select soil samples were submitted for analysis. Advanced GeoEnvironmenfal,Inc.