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Mr. Jeffery Wong Page 4 Subsequent to well development, groundwater samples will be collected from the wells after pH, temperature, and electrical conductivity have stabilized and the wells have recharged to minimum of 80% of static levels. Water samples will be placed in appropriate containers, labeled and placed in an ice chest at a temperature of 4 degrees Centigrade for shipment to the laboratory under chain of custody protocol. Analysis will consist of TPHg, BTEX, gasoline oxygenate additives, DCA and EDB. Additional Vertical Investigation To further define the vertical extent of contamination in the soil and groundwater, a Cone Penetrometer Testing (CPT) boring set will be advanced in the vicinity of the former tankpit. One boring will be advanced to approximately 110 feet bgs utilizing CPT instrumentation to determine the underlying stratigraphy and to identify specific target intervals for soil sample collection. The CPT hole will then be twinned for the collection of soil and groundwater samples. Sample collection will begin at a depth of 80 feet and terminate at a depth of approximately 110 feet and/or refusal which ever comes first. Upon completion, the boreholes will'be backfilled with cement grout to ground surface using a tremmie pipe. Soil samples will be collected for analysis from intervals of lithologic interest as identified from the CPT data and from intervals bearing field evidence of contamination. At least two consecutive samples at five-foot intervals from the bottom of the boring will be submitted for laboratory analysis. Discrete groundwater samples will be collected from approximately 80, 90, 100 and 110 feet bgs. Groundwater samples will be collected by using a discrete sampling device(Hydropunch or equivalent) driven into the water bearing zone. In the event that the sampler screen clogs or for other reasons groundwater will not enter the device in suitable quantity, a grab sample will be collected through the rods. Analysis of soil and groundwater from the additional boring will consist of TPHg, BTEX, gasoline oxygenate additives, DCA and EDB. Samples selected for analysis will be immediately capped, labeled and placed in an ice chest at a temperature of 4 degrees Centigrade for shipment to the laboratory under chain of custody protocol. Sensitive Receptor Survey Sensitive receptors, including wells, surface water bodies, schools and (to the degree possible) subsurface utilities within a radius of 2,000 feet of the site will be identified. Locations will be plotted on a map and pertinent information tabulated and included in the technical report. Reporting Following the receipt of analytical results, a technical report describing the methods and results of this investigation will be submitted to PHS/EHD. The report will describe to the degree possible the nature and extent of contamination, and will contain recommendations for additional work as appropriate. Harrys\reports\workp1an3mws