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Ms Lori Duncan . Page 3 of 5 site to investigate the potential impact to groundwater from contaminants previously released at the site. Boring SB I A was located in the former UST excavation, (Figure 2). The boring was advanced to a depth of approximately 36 feet bgs. Spectrum Exploration, Inc. (C-57 License No. 512268) drilled the boring under the supervision of field geologist Sean Garvey and project manager Gregory Stahl, a California Registered Geologist, Ms. Lori Duncan with PHS/EHD observed field activities and conducted the site inspection. Spectrum utilized a CME 55 drilling rig equipped with hollow stem augers to advance the boring and collect soil and groundwater samples. Beginning at a depth of 25 feet, soil samples were collected at 5-foot intervals using an 18-inch long core sampler lined with new 2-inch diameter brass sleeves, affording soil identification and subjective evaluation for contamination. Subsequent to collection, the samples were sealed, labeled, and immediately placed in an ice chest cooled to a temperature of approximately 4 degrees Centigrade. The samples were transported to Argon Laboratories, Inc. (FLAP No. 2359) under chain of custody protocol for analysis. Groundwater was first encountered in boring SB 1 A at a depth of approximately 32.5 feet bgs, and remained static at that depth. A discrete groundwater sample was collected from the boring using a Hydropunch-type sampling tool from an interval of 35 feet bgs to 40 feet bgs. Spectrum . drove the sampler to the desired depth, and pulled back on the rods to expose the screen to the formation. A stainless steel bailer was lowered through the rods to the bottom of the sampler. The water sample was then collected, dispensed directly into the appropriate sample containers, and placed into an ice chest cooled to a temperature of approximately 4 degrees Centigrade. The groundwater sample was transported under chain of custody protocol to Argon Labs for analysis. The completed boring was backfilled to the surface with neat cement grout. Soil cuttings and rinsate collected from decontamination procedures was contained on site by placing in appropriately labeled DOT approved 55 gallon drums pending disposal. RESULTS OF INVESTIGATION Subsurface Conditions In boring SB 1 A3/4 inch gravel fill material was present to a depth of approximately 20 feet bgs. From approximately 20 feet to 26.5130 feet soil was classified as a clayey sand. From a depth of 26.5/30 feet to 31.5135 feet silty clay was present. No samples were recovered from the interval 35-36 feet. This material may have been flowing sand. Groundwater was encountered at approximately 32.5 feet bgs. No odors or abnonnal discolorations were observed in the soil sampled collected from the boring. A soil boring log is included in Attachment A. tsautolreporWaddsubsurfsum.doe