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G. 17 November 2003 AGE-NC Project No 95-0103 Page 2 of 5 In accordance with EHD/CVRWQCB directives and approval,AGE conducted three separate ground water extraction pumping tests in March 2001 Analysis of the groundwater extraction data indicted that ex-situ ground water treatment was feasible,the radius of influence generated by a pumping rate of three gallons per minute is Interpreted to be adequate to control further off-site migration of contaminants toward the west Under EHD directives and approval, a ground water pump-and-treat system began continuous operation at the site on 02 April 2002, the system has operated for approximately 18 months Over this time period approximately 2 5 million gallons of impacted ground water was treated and estimated cumulative totals of 5 69 lbs of benzene and 140 lbs of TPH-g were extracted The remediation-goals presented to the EHD by letter dated 10 August 2001 proposed that removal of 80 percent of the mass of dissolved hydrocarbons,or diminished remediation effectiveness,would be acceptable clean up goals for the site Presently,at most impacted ground water monitoring wells, the contaminant concentrations have been reduced to approximately 1 3%benzene and 7 5%TPH-g of the pre-remediation levels Additional site history and findings from previous investigations and monitoring events at the site are detailed in the Corrective Action Plan (CAP) and the Quarterly Reports prepared by AGE s SCOPE OF WORK AGE proposed to install five soil boring under the building at the site to determine the remaining lateral and vertical extent of petroleum hydrocarbons in soil and to verify the removal of the hydrocarbons from the vadose zone Three soil boring were previously approved by the EHD by letter dated 16 January 2001, however, two additional boring location have been verbally required by the EHD PROPOSED DRILLING AND SAMPLING Five soil boring will be advanced to a depth of 30 feet bsg or deeper based on field indications and measurements The soil borings will be installed at a 30 degree angle, using a truck-mounted GeoProbe ng and 1 5-inch hollow stem push rods Soil samples will be collected continuously with a 2-inch GeoProbe Macro soil sampler The soil boring locations are illustrated on Figure 2 Advanced GeoEnvironmental,Inc