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a licensed surveyor; the results are shown on EXHIBIT C . On June 4, 1996, 450 gallons of purge water were transferred to American Valley Environmental Services under Manifest #95682308 . A copy of that document is included as EXHIBIT D. On June 25, 1996, ten (10) drums of drilling spoils were trans- ferred to Forward Inc . for disposal . A copy of that manifest is included as EXHIBIT E . DETAILS OF GROUNDWATER MONITORING PERFORMED JUNE 28, 1996 : On June 28, 1996, Del-Tech Geotechnical Support Services performed the quarterly testing and sampling of the four wells . The work was done according to WJH & San Joaquin Co. EHD field protocol as directed by our office . The attached PLATE I shows the direction of the groundwater gradient indicated by the nine (9) measurements taken to date . The most recent data shows the hydraulic gradient has shifted back to the north, the direction of all but one of the measure- ments taken to date . Only the 3/96 sampling event indicated a southerly direction. The slope of the potentiometric surface continues to be quite low, at about .007 ' /foot, or 35 ' /mile . The water table was measured at an average depth of 9 .37 ' below grade, a drop of slightly over one foot since the March sampling event . The results of laboratory analyses of water samples from the four wells are summarized on TABLE I ; copies of the lab reports are included with the details of the field work which is attached as EXHIBIT F. Water samples from MW-1, MW-3, & MW-4 were all below detection limits for BTEX, MTBE, AND TPHg. The San Joaquin County EHD stated that sampling of MW-2 is not required at this time since it was within the plume . Water level measurements are to be determined for all four wells, however. CONCLUSIONS : Based upon results of work done to date at this site, the following conclusions appear to be valid: 1 . As indicated on PLATE IV, the limits soil & water contami- nation have been fully defined in all directions . The plumes extend off the property under Stockton Street, but do not reach private properties to the east . 4� 3