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l 29 March 2002 AGE-NC Project No. 99-06371 Page 4:of 6 MW5, MW6 and MW7 to the nearest 0.0f-foot relative-to City.of.Manteca Bench Mark #63 at 33.758 feet above.mean sea level (msl).'The results ofthe monitoringwell survey-are contained in Table 1. The surveying report.(Baumbach &Piazza, Inc.) is presented in.Appendix D. 3.0. FINDINGS Ground water elevation, flow direction, and gradient were determined from field data collected on 31 January 2002;the contaminant impact'to soil and ground water was quantified by the laboratory analytical,data. _ 3.1. -STRATIGRAPHY R_ ' Generally, light brown to tan, dry to'saturated, poorly'graded sand was encountered from surface grade to approximately 10 feet bsg and at 20 feet bsg. Gray.to brown, damp to saturated, sandy silt ' and silty clay was encountered at.15 feet bsg, 25 feet bsg and 30 feet bsg. Lines of cross section are illustrated on Figure 2 and stratigraphic cross sections are depicted on Figures 5, 6 and 7. Organic.vapor was not detected in the soil samples collected. PID data, such as it is, is included on the boring logs(Appendix A):; 3.2: . GROUND WATER GRADIENT-AND FLOW DIRECTION At the time of the January 2002-sampling event, depths to ground water in.well sMW 1'through: MW7 ranged from 15.53 feet to 17.03 feet below the well heads. Ground water elevations at the site t ranged from 17.49 feet above mean sea level(MSL) in wells MW1 and-MW4'to 17.70 feet above MSL in well MW6 (Table 1). During this monitoring event,the depthsjo ground water in the wells were approximately 5.53 to 7.03 feetbelow,the tops of the well screens,indicating that the wells are screened properly to yield representative shallow.ground water samples. The ground water flow direction was calculated using :ground_ water elevation data from the, monitoringwells on-site. The flow direction was calculated to be generallytoward the northeast at g Y a gradient of 0.002 feet/feet..Figure 3.illustrates the;contoured ground water elevations as measured t on 31 January 2002. Advanced GeoEnvironmentaii Inc.