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appear very high in relation to other samples at comparable depths. For this reason, a theory was proposed that the high level of chlorides in well #2 may have been caused by purge water from well #2 leaching salt from the backfilled soil located nearby. From previous exploration, this backfilled soil is known to contain a high chloride content as a result of decayed pipes leading to the abandoned leach field. Because of the extensive sampling data already available at several depths in this location near the pond, MEC feels that continued testing in this area will not result in any additional information. In the future, purged water will not be pumped to the backfilled area. If this theory is correct; water samples collected in the future should no longer show an increase in chloride content. Work Plan to Investigate Two Old Production Wells As mentioned in the "Site Characterization Report" , two old production wells exist on the Southwest Hide property. It is not known how long these wells have been out of use. They are believed to be possible vertical conduits for chloride contamination and should be examined. Examination will begin by exposing the top of the well casings. Previous investigation has revealed that the well casings are below the ground surface. An extension will be welded onto the existing casing to bring it above ground surface elevation and a utility box installed. Once this has been accomplished, the wells will be pumped to remove the sediment that has filled them. After the wells have been cleaned, the total depth of the well will be determined and water samples collected from the wells at different depths to determine if elevated contaminant levels are present. It is anticipated that a submersible television camera will then be used to determine the depth and extent of the perforations. The television monitoring will also reveal the condition of the casing and the extent of any damage that may exist. Based on this information, the feasibility of using the wells to mitigate the current chloride plume will be examined along with the possibility that these wells have served as vertical conduits for chloride migration in the past. If it is determined that the wells will be a potential hazard to accelerated pollution migration, it will be abandoned as per San Joaquin Local Health District standards as soon as possible; otherwise the well will remain open and used to supply characterization information. We anticipate to begin cleaning out the wells during the week of May 22-26, 1989. Response to Recommendation to Install an Additional Deep Well In response to the Regional Board' s recommendation for the installation of an additional deep well in the area containing 3 of 4