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18 July 2002 , AGE-NC Project No 95-0109 Page 2 of 8 full-scale inoculation with hydrocarbon-consuming bacteria Details of well inoculation can be found in the GeoAudit-prepared Quarterly Report- September 1994, dated 18 October 1994 In May and September 1998 and January 1999 hydrogen peroxide was added to selected wells to , increase dissolved oxygen concentrations and promote biodegradation The most recent soil borings, were advanced in February 1999,to assess the progress of the in-situ bioremediation Results of the investigation indicated that 90% of the hydrocarbons impacting soil had been remediated A summary of in-situ bioremediation canbe found in the AGE-prepared Quarterly Report-March and June 1999 dated 11 August 1999 Further background information including the site history, description and results of previous, investigations are detailed in the Problem Assessment Report (PAR) dated 31 July 1991, prepared by PES Environmental,Inc ,and in the AGE-prepared reports Quarterly Report-March 1996 dated 19 April 1996 and Quarterly Report-March and June 1999 dated 11 August 1999 21 CONE PENETROMETER TESTING INVESTIGATION • From 18 to 20 December 2001,two soil borings(CPT-1 and CPT-2)were advanced on-site and one soil boring(CPT-3)was advanced off-site(121 Cherokee Lane)utilizing cone penetrometer testing (CPT)technology to model the geological and hydro-geological framework and to assess potential dissolved petroleum-migration pathways beneath the site Based on CPT-defined hthologic properties, AGE identified three subsurface hydrologic units (HUs), at between 45 and 65 feet bsg (HUI), between 65 and 95 feet bsg(HU2) and between 95 and 140 feet bsg (HU3), the hydrologic units are depicted in Figure 4 A total of nine grab ground water samples were collected from CPT-1, CPT-2 and CPT-3 and submitted for laboratory analysis Ground water samples were collected from CPT-1 and CPT-2 at depth intervals of 72 feet to 76 feet bsg(Hydrologic Unit 2-HU2), 92 feet to 96 feet bsg(HU2)and 110 feet to 114 feet bsg (HU3), from CPT-1 at 130 feet to 134 feet bsg (HU3), and from CPT-3 at 76 feet to 80 feet bsg(HU2)and 110 feet to 114 feet bsg(HU3) Figure 1 depicts the location of the CPT soil borings Figures 3 and 4 illustrate the lithology, location and concentrations of water = samples collected during the CPT investigation Total petroleum hydrocarbons quantified as gasoline(TPH-g)was detected in eight of the rune water samples collected from CPT-1,CPT-2 and CPT-3 at concentrations ranging from 60 micrograms per liter (gg/1) to 500µg11 TPH-g was detected in the deepest water samples collected from CPT-1, CPT-2 and CPT-3 at concentrations of 60µg/1, 180µg11 and 60µg/l,respectively The vertical extent of TPH-g-impacted ground water has not been defined at the site Advanced GeoEnvironmental,Inc