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r i Wright relocated original borings (B-I. through B-4) positions from fi.eld notes and then had to relocate.B-5, .B-6,B-8 and B-9 since a large construction project that required extensive shallow groundwater dewatering had been. completed since 2003. This new construction includes major underground utilities, new buildings and a clarifier in the vicinity of Boring B-2 that has changed the site significantly since the PEA work in 2003. The boreholes were drilled with truck mounted GeoProbe 6600 direct-push drilling equipment. All drilling equipment and sampling tools were cleaned prior to arriving, between each sampling borehole and before leaving the site. The probe collected continuous cores of soil in each borehole. The sampler was then retrieved and dissembled and soil sample intervals retained for chemical analysis were cut from the liners at the desired depths. The soil sample was sealed with Teflon paper or foil and plastic endcaps, labeled, logged onto chain-of.-custody forms and placed in a chilled ice chest on crushed ice for transport to the laboratory. The boreholes were continuously .logged using the Unified Soil Classification System under the supervision of a professional geologist. Additional lithologic information was collected as needed to describe the subsurface geology. Soil samples were field screened with a portable photoioni.zation detector (Mi.nirae 200 PI.D meter pre-calibrated by the supplier) for petroleum fuel hydrocarbon vapor and also visually checked for staining. Upon completion of the borehole drilling and collection of water samples, the boreholes were backfilled with cement grout, placed from the bottom to top of the borehole per the permit requirements. All soil cuttings, decontamination and cement mixing water and sample tubes and other consumable items used in sampling were left in labeled 55-gallon closed top drums. The drums were labeled and stored at the Client-specified location,Boyd Service Center. 3.1 Field Methods - Groundwater Sampling Groundwater samples were collected in each borehole from depth intervals of about 15 to 25 feet within the shallow aquifer. A brief summary of the sampling procedure follows: Each borehole was advanced into the aquifer and temporarily cased for sampling. Depth to groundwater measurements were attempted to the nearest one-one hundredth of one foot (in some cases water levels did not stabilize), and visually checked for the presence of separate phase product. The water entering the borehole was sampled using a clean bailer, and carefully poured into the appropriate laboratory prepared container with minimum cavitation. Each water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest on crushed ice for transport to the laboratory. 3.2 Field Modifications of the Work Plan.for Sampling and Chemical Analysis A large construction program had occurred since the PEA work in 2003 with the installation of a large concrete clarifier near Boring location. B-2. As a result of this construction and new large utilities, borings were re-located as neededin field discussions the E14D representative. The work plan had initially planned for soil samples to be analyzed for Diesel and Gasoline fuel components for this assessment. A field discussion with the EDH representative indicated that given the initial. soil and groundwater analyses results showing that Gasoline fuel and related compounds were not detected, only Total Petroleum Hydrocarbons as Diesel (TPM) would be needed for this soil and groundwater sample and analysis work. Page 3 of 9