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*ft► .r 18 May 2001 AGE-NC Project No. 97-0326 Page 2 of 3 Background information and site history is summarized in the AGE-prepared Monitoring Well Installation Report dated 02 June 1999. SCOPE OF WORK The proposed scope of work includes advancement of four paired deep soil borings,one pair at each of two locations, to delineate the vertical and lateral extent of impacted soil and ground water and to obtain the geologic information necessary to properly assess and monitor ground water. AGE proposes to initially advance one paired boring to a depth of 150 feet on the west side of Stanislaus Street, based on the CTP results from the February 2001 survey in which a grab water sample at 93 feet at the K & S site and another water sample collected off-site at 122 feet were assessed to be impacted;the vertical extent of contaminated ground water has not been fully defined on the site. The first boring will be a cone penetrometer (CPT) hole; the CPT will acquire a continuous soil response record to define lithologic and hydrologic units; the paired boring will be advanced to acquire soil and grab ground water samples in targeted zones based on the interpreted CPT lithologic data and assessment needs; if petroleum hydrocarbon odor is detected from the sample collected at total depth, the boring will be advanced in additional 10-foot increments and water samples collected until no field indications of hydrocarbons are detected in two consecutive samples. Due to time constraints and as soil samples will be collected during installation of the monitoring wells, soil samples will only be collected at selected depths at the CPT locations. The second boring location will be near MW 1 (Fig. 2), which is near the UST area and where the highest hydrocarbon concentrations have been encountered in subsurface soil samples. The total depth of the final CPT boring pair will be based on the results from the first boring location. Soil samples will be collected from selected lithologic units as defined by the CPT data and previously-collected soil-sample data at the site. The strategy for soil sampling is to collect samples from the tops of fine-grain units underlying significant coarse-grain units in the UST area. Soil samples will be preserved as described in the 09 July 1998 Monitoring Well Installation Work Plan. Grab ground water samples will be collected from selected hydrologic units as identified by the interpreted CPT data;the samples will be placed in 40-m1 VOA vials for analysis.In addition to total petroleum hydrocarbons (gasoline), volatile aromatics, and oxygenates, samples also will be analyzed for 1,2 DCA, EDB, ethanol and methanol. Refusal was encountered at 122 feet bsg in the third CPT boring location on 15 February 2001,partly because a very stiff lithologic unit was encountered and partly because the CPT reentered an existing bore hole, which provides less lateral stem support than a new bore hole. AGE does not foresee problems boring down to the anticipated depth of 150 feet bsg; however, in the event refusal is encountered before the investigative objectives are reached,the CPT attempt will be abandoned and a drill rig brought in to complete the investigation. Soil samples will be collected and preserved as described in the Monitoring Well Installation Work Plan. Advanced GeoEnvironmental,Inc.