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�- a a b leen done. The fourth recorrtriendatioil was that one, drive point well be placed directly under the point of cor)taint nat,ion ( ihc° pit was much smaller at that tirrm) to determine possible impact on ground water . This obje;tive has been achieved by the digging of the excavation to -45'g. 1 . and the subsequent szimpIing and ana- Iyzing of both bottom soil and groundwater influx into the exca- vation. The GTI report indicated a southeasterly direction of groundwater flow. 1=igure 5, the San Joaquin County Flood ControI regional water level map, spring of 1989, shows a southerly direction of flew, which is in general accordance with the GTI measurements. NMI-2 is currently located in a position to detect contamination from either southerly or southwesterly flow. A southeasterly flow plume could possibly miss his well ; however , the groundwater tested from pit seepage should have indicated such if it had ; occurred. A need for two additional monitoring wells was stated by SJLHD in their letter of 3/2/88 (Appendix A-3) ; one of which could be pre- cluded by "removing contaminated soil to groundwater in this area . " The contaminated soil has been removed and as discussed earlier , an extensive soil and water testing program carried out , as directed by the DHS. The level of work done should be adequate to preclude a need for any more monitoring wells. RECQ1'MEIVDA"T I QNS A quarterly water sampling and testing program is recommended for the current monitoring wells until such time that the DHS and CVRWQCB are satisfied that no groundwater contamination exists. These wells, although not ideally placed to detect a southeast- erly plume of contamination, are in place and should be restored to usable condition. Proceed with a program for soil remediation and/or disposal ; the ultimate goal being the filling- in of the excavation and making possible a higher use of the land. Program I . Repair the monitoring well heads by adding extensions to the 2" plastic well pipe, including a cap and a device for locking. The wells should extend above the ground and be plainly visible so as to preclude shearing them again during remediation. 2. Revise the surveyerj well heads elevations by carefully meas- uring from the sur-.,;ved ne '. L to the top of the new, uncapped 3. Clean all well ,, oy air purging and air lifting when water is 14