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Geological Technics Inc. Page 5 Additional Site Characterization Work Plan Project No.723.2 s December 10,2007 that could act as a preferential pathway for contaminant transport. If no sand layers are encountered the screens of these wells will be placed in the same intervals as the MW- 208/308 well sets (76'/89'). • Boring MW-212 will be sampled at five foot intervals from the surface to 70 feet bgs to confirm the lithology identified in the CPT-3 borehole location. The borehole will then be continuously sampled from 70 to 100 feet bgs. The depth of the well MW-212 screen will be targeted to intercept deeper sand layers that could act as a preferential pathway for contaminant transport. The MW-112 intermediate well boring will be free drilled to total depth. The screened interval of this well will also target sand layers that could act as a preferential pathway for contaminant transport. If no sand layers are encountered the screens of these wells will be placed in the same intervals as the MW-208/308 well sets (76'/89'). • Boring MW-213 will be sampled at five foot intervals from the surface to 100 feet bgs. If field evidence of contamination is present then the well will be continuously logged throughout the impacted interval. The depth of the well MW-213 screen will be targeted to intercept deeper sand layers that could act as a preferential pathway for contaminant transport. The MW-113 intermediate well boring will be free drilled to total depth. The screened interval of this well will:also target intermediate sand layers that could act as a preferential pathway for contaminant transport. If no significant sand layers are encountered the screens of these wells will be placed in the same intervals as the MW- 208/308 well sets (76'/89'). Boring logs will be developed by a GTI geologist working under the supervision of a professional geologist. The log will be prepared using the U.S.C.S. and field observations to provide sediment descriptions. Soil samples will be collected in 6.0-inch brass liners using a 2.0-inch modified California split spoon sampler. All soil samples will be sealed with Teflon sheets, capped, labeled and placed in a cooler at 4° Celsius for transport to the laboratory following Chain of Custody protocol. A field observation process will be used to gather additional information through noting sediment type, especially grain size and clay content; moisture content; visible evidence of contamination, i.e., color change due to reduction of iron or discoloration from hydrocarbons and other pollutants, and any readings above background levels on an organic vapor meter (OVM). 2.2.3 Soil Sample Analyses Up to four soil samples from each deep borehole will be submitted to a State certified laboratory for the following analysis: • Benzene, toluene, ethyl benzene and xylene (BTEX)by EPA method 8021M or 8260 • Gasoline range petroleum hydrocarbons(TPH-G)by EPA method 8015M or 8260