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Mr Jeffrey Wong . Page 4 of 10 3.2 Drilling and Sampling On January 31, 2001 through February 3, 2001, three soil borings were advanced and subsequently converted into groundwater monitoring wells Spectrum drilled and installed monitoring wells and Gregg performed CPT and direct push drilling under the supervision of field geologist Sean Garvey and project manager Gregory Stahl, a California Registered Geologist Mr Jeffery Wong PHS/EHD conducted the site inspection and observed field activities Boring MW2 was advanced approximately 44 feet south west of MWl Boring MW3 was advanced approximately 47 feet east of MWI Subsequent to determining groundwater flow direction, boring MW4 was advanced approximately 50 Feet north of MW 1 Soil boring locations are shown on Figure 2 Boring logs are included In Attachment A Soil samples were collected with an 18-inch long core sampler lined with new 2-inch diameter brass sleeves, affording soil identification and subjective evaluation for contamination The soil was classified by traditional soil logging techniques using ASTM Designation D2488-90, which is equivalent to the Unified Soil Classification System A photo Ionization detector (PID) was used to monitor the presence of volatile organic compounds in the soil After collection, the samples were sealed, labeled, and Immediately placed in an iced cooler and transported to Argon under chain of custody protocol Soil sample selection was based on field observations and screening results Groundwater was first found in borings MW2 through MW4 at depths of approximately 47 feet bgs Subsequent depth to groundwater measurements Indicated that the water level was static Soil cuttings were contained on site by placing on, and covering with plastic sheeting All down- hole drilling and sampling equipment was decontaminated by steam cleaning Rinsate collected from decontamination procedures was contained in 55-gallon drums The soil and rinsate are currently stored on site pending proper disposal options 3.3 Well Construction Based on statigraphy, current depth to groundwater measurements and historical depth to groundwater measurements, wells MW2 through MW4 were screened from 35 to 60 feet bgs The wells were constructed of 2-inch diameter, Schedule 40 PVC casing and 0 020 inch slotted screen The filter pack consisted of#3 silica sand The annular seal contained 2 feet of bentonite overlain by neat cement grout to the ground surface Well construction logs are included in Attachment A 3.4 Well Development and Groundwater Sampling On February 7, 2001, the wellhead elevations of the new monitoring wells were surveyed, groundwater levels were monitored and the wells were developed and sampled datalgrounze%arryslweIIrepotI doL.