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25 May 2001 AGE-NC Project No. 98-0426 Page 2 of 6 in grab water samples collected from borin,-s B 1, B3 and B5 at concentrations of 250 micrograms per liter(�Ig/1), 12,000 ug/l and 220 ug/1,respectively. BTEX were detected in the grab water sample collected from boring B1 at concentrations of 32 ug/l, 1.7 p g/l, 12 ug/1 and 6.0 ugd, respectively, Ethylbenzene and xylenes were detected in the water sample collected from boring B3 at concentrations of 200 ug/l and 720 p.g/l, respectively. On 19 October 1999, three monitoring wells (MW-1, MW-2 and MW-3) were installed to a depth of 35 feet below surface grade (bsg) at the site. TPH-g, ethylbenzene and xylenes were detected in the soil sample collected from boring MW2-20 at concentrations of 630 milligrams per kilogram (mg/kg), 3.6 mg/kg and 13 mg/kg, respectively. TPH-g and BTEX compounds were detected in samples MW3-20 and MW3-25 at concentrations as high as 11 mg/kg, 0.24 mg/kg, 0.049 mg/kg, 0.36 mg/kg and 0.49 mg/kg, respectively. Petroleum hydrocarbons were not detected in sample MW2-25. Based on the soil probe and monitoring well boring results, it appears that petroleum hydrocarbons have not been detected in soil samples collected at depths greater than 30 feet bsg;the vertical extent of impacted soil beneath the Former USTs is defined. Also, petroleum hydrocarbons were not detected in soil samples analyzed from borings B 1, 132, B4, B5 and 136; thereby defining the lateral extent of impacted soil. Since AGE began quarterly aground water monitoring activity at the site in October 1999, ground water gradient determinations have indicated a consistently northeast ground-water flow. However, the vertical extent of impacted ground water is not yet defined, nor is the lateral extend defined towards the northwest and the south. Complete background information and details of previous investigations at the site is included in the report titled Preliminan,Investigation and Evaluation Report - March 1999, prepared by AGE. 3.0. SCOPE OF WORK The scope of work will include the advancement of three soil probe borings, one (B-7)at the UST location, another(B-8) at the northwest comer and a third(B-9) directly south of the UST location. Boring B-7 will be advanced to a depth of approximately 60 feet bsg; borings B-8 and B-9 will be advanced to a depth of approximately,*feet bsg. Soil and ground water samples will be collected from probe borings B-8 and B-9; since �il samples have been collected at discrete intervals down to 60 feet bsg from a previous soil boring at the UST location, only grab ground water samples will be collected from boring B-7. The scope of work will require completion of: Advanced Geo Envirun mental.Inc.