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23 July 1998 AGE-NC Project No. 98-0463 Page 2 of 4 Depth to Groundwater Spring 1996 and Lines of Equal Elevation of Groundwater Spring 1996 published by the San Joaquin County Flood Control District and Water Conservation District (FCD&WCD). Extending the contours slightly,the estimated depth to ground water at the property is approximately 10 to 20 feet below surface grade (bsg) and are suggestive of local ground water flow toward the northwest on the property. Reports from area sites undergoing ground water monitoring place ground water at depths of approximately 10 to 15 feet bsg. The flow direction may be greatly modified by local recharge and discharge patterns and several active wells are in the immediate area, which could locally affect flow direction and depth to water. Ground water is considered to be of beneficial use and is used for domestic, industrial and commercial purposes. 2.3. PURPOSE OF INVESTIGATION During the course of a Phase I site investigation, three nearby sites were identified that could potentially impact ground water on the subject property. East of the subject property lies a former magnesium plant that had a large tailing pond, southwest of the subject property is the Lague Sales property that was listed as a California Bond Expenditure Plan (state super fund) site due to impacting soil with pesticides, fumigants, metals and solvents. No evidence of analysis of ground water samples collected from the site was found during the course of the investigation. North of the subject property is a property occupied by Steelgard, Inc., with an on-site impoundment. Although AGE has no evidence that any of the sites noted above have impacted ground water, the shallow depth to water,the proximity of these sites to the subject property and their apparent scales of operation makes it prudent to check ground water on the subject properties to assess for encroaching suspect contaminants. 3.0. SCOPE OF WORK 3.1. PROBING AND SAMPLING A subsurface investigation at the site is necessary to determine if impacted ground water is present at the site. AGE proposes to advance five soil probe borings at the site to collect ground water samples on the margins of the subject properties. AGE found no evidence to suspect any soil contamination on the subject properties, so no soil sampling is planned. Probe borings will be advanced to depths of approximately 20 feet, if required to reach ground water, using direct push technology (DPT). The proposed probe boring locations are illustrated in Figure 2. Grab ground water samples will be collected from the probe borings using a Geoprobe water sampling assembly. For the sampling assembly,probe rods will be fitted with a retractable ground Advanced GeoEnvironmental,Inc.