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Page 3 Geol#UI necluurs Inc. Additional Site Characterization &4''Quarter Groundwater Monitoring Project No. 1030.2 February 20,2004 r2.1 Monitoring Well Installation On November 12, 2003, a hollow stem auger drill rig owned and operated by V&W Drilling (C57# 720904) arrived at the site. The rig was set up near the location of the proposed monitoring well. The location was adjusted slightly due to multiple power and phone Lines in the area. The monitoring well was constructed using 2.0-inch diameter schedule 40 PVC casing with flush threads. The details of construction are listed in the table below and a summary of well construction is included as Table 1 in Appendix A. i GreenSlot I Sandac raps. cal I Grout Seal san - -sur ace Groundwater was first encountered at approximately 14 feet bgs in the borehole. A #3 sand filter pack surrounded and extended not less than one foot above the 0.010 inch screened interval and was topped by a one-foot bentonite chip transition seal installed on top of the filter pack. A surface seal was achieved by pumping a neat cement grout (augmented with <4% bentonite). The wells were surged using a clean surge block to achieve maximum filter pack density prior to installing the bentonite transition seal. The well was secured with a locking watertight cap encased in a flush mounted traffic rated well box. The boring logs (Appendix C) contain the details of construction. Soil cuttings and drilling decontamination water were placed in DOT-17 55-gallon drums and stored on site until their disposal can be arranged. ' 2.1.1 Soil Sampling Procedure On November 12, 2003, V&W Drilling and Geological Technics personnel mobilized to the Sinclair Trucking site. Eric L. Price, GTI geologist, collected soil samples and maintained a log from the soil borings. The samples were gathered in 6,0-inch brass liners using a 2.0- inch modified California split spoon sampler. The middle 6.0-inch brass liner was selected for laboratory analyses. The ends were covered with Teflon sheets and sealed with plastic caps. The brass liners and plastic caps were washed with an Alconox solution and double rinsed prior to use. The sampling technician wore disposable gloves while collecting all samples. ' Two soil samples from the boring were submitted for laboratory analysis and a screening process was used to gather information through field observations. The field screening included: ' • 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) --- • Odor (measured via OVM, a portable photo ionization detector that uses a 10.6 eV lamp ' to detect compounds with ionization potential below 10.6 eV). Details on the geology encountered during the well installation, as well as the field observations, are included in Section 3.2, Geology and Field Observations.