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w CONCLUSIONS The water table elevations on this site continue to fluctuate Concentrations of TPHg have continued fluctuating in the shallow wells with the rise and fall of the groundwater elevation(See contour map of Max TPHg levels attached) The groundwater gradient was to the northeast for this event, the same direction and slope as the last event This event continues the more traditional flow direction It may be concluded that when the groundwater elevation raises,the gradient changes from westerly to easterly RECOMMENDATIONS The work plan under construction should address many concerns about the scope of the investigation of both 1,2-DCA and the other oxygenates Results from the CPT work indicate that the1,2-DCA contamination has reached the middle of the building and is moving to the west (see contour map of Max Levels of 1,2-DCA attached) It is recommended that the site continue to be monitored on a quarterly basis Monitoring well MW#1D was installed to a depth of 150' Groundwater samples from this event indicate the presence of 1,2 DCA concentrations above drinking water standards(25 ug/L)at a depth greater than 150' in area of monitoring well MW#1D The groundwater sample from MW#1D may have been contaminated from the installation of the MW#ID soil bore We should wait for the results of the third quarter monitoring event before proceeding to install monitoring wells to depths greater than 150' to determine the vertical limits of 1,2 DCA contamination WORK IN PROGRESS Quarterly monitonng of the existing monitoring wells continues Preapproval of the work plan for installation of five CPT's and three momtonng wells has been approved by the UST Fund,and the CPT's ihave been installed The installation of the one of three monitoring wells has been completed Reimbursement for soil removal was requested for preapproval,but has not been approved by the UST Fund INSTALLATION OF MONITORING WELL MW#1D REPORT Install 5/28/2003 PROCEDURE On May 27, 2003, Spectrum Drilling dulled an 8" bore hole to a depth of 150' Soil samples were extracted at 25' of depth and from 60' to a termination depth of 150' at five foot intervals A 2" PVC casing was installed with screen from 145'to 150' The monitoring well was developed and purged to industry standards by Spectrum SOIL SAMPLE ANALYSIS Soil analysis indicates TPHg in detectable ranges from 25 to 70 feet of depth Samples analyzed for oxygenates in soil by EPA Method 8260 indicate 1,2 DCA to a depth of 85 feet(See attached recap of analysts) SOIL SAMPLE CLASSIFICATION AND MONITORING WELL CONSTRUCTION All soil samples were classified by the visual method and are shown on the attached Bonng Log Monitoring well construction is shown on the right side of the attached Bonng Log 3