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---------------- �(YVAT C A S S O C I A T E S I N C `.A A I c-= In April and May 2001, ATC Associates supervised the advancement of five soil borings, SB14 through SB18, to approximately 21 to 26 feet below grade. Four of the borings were located on the adjacent parcel north of the site and one boring was located on the northeast corner of the site. A groundwater sample was collected using a hydropunch from each boring at the depth groundwater was first encountered, approximately 15 to 20 feet below grade. The soil and groundwater samples were analyzed for TPHd. Samples from soil boring, SB17 collected at 15 feet bgs contained detectable concentrations of TPHd of 61 ppm. Groundwater collected from boring SB 17 contained detectable concentrations of TPHd of 98 ppb. The soil and groundwater samples collected from the remaining borings did not contain detectable concentrations of TPHd. The activities and results are detailed in the Summary Report, Subsurface Investigation, dated '`-- August 1, 2001. F= 2.0 METHOD AND PROCEDURES All work described herein was performed in accordance with ATC's Workplanfor Installation o F. Groundwater Monitoring Well at Smiths Canal Pump Plant, Fontana Avenue, Stockton, California, dated January 31, 2002, which was approved by PHSIEHD. The scope of work completed included obtaining permits, locating underground utilities, advancing a soil boring, soil sampling, groundwater monitoring well installation, well development and quarterly =.; groundwater sampling, and the laboratory analysis of selected soil and groundwater samples. 2_1 Drilling Activities On January 25, 2002, a geologist from ATC Associates and a subsurface locator visited the site ;._ to clear potential drilling locations from underground utilities. It was determined that it would be 3 impossible to advance the boring at the proposed location in the workplan without encountering an underground utility. The well was relocated the shortest distance possible to the west. The =_ parcel to the east is owned by Caltrans. On February 1, 2002, a geologist from ATC Associates supervised the advancement of one soil boring to 26.5 feet b s• The soil boring was completed as a monitoring well. A site plan showing the well locations is included as Figure 2. Woodward Drilling, California License C57 -j 710079, advanced the boring using a hollow stem auger drill rig. Soil samples were collected at five foot intervals in stainless steel sampling tubes and were described according to the Unified Soil Classification System. Descriptions of soil types encountered and sample collection ... intervals intervals are presented on the boring log contained in Appendix A. w:\Wordpro162574162574.021Reportslwell_install.doc 4 j�t;-e