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a 44k— v 31 ! t F Page � Trust for Mary Gardella f June 26, 2003 • The boring and chernical data will be discussed with PHS EHD and used to locate additional groundwater monitoring wells for site monitoring with especial regard to the potential 1, 2-DCA pathways. This may include drilling "ciustee' wells sets at locations selected on the basis of this additional CPT data. • Once the well locations are agreed, permit and install the initially proposed groundwater monitoring wells. The well locations proposed in the initial workplan may be revised on the basis of the new data. The goal will be to provide site definition in groundwater monitoring of the three water bearing zones of interest and more fully identify contaminant pathways. • When the well locations are selected, Wright will review the feasibility of using a multiple level monitoring well. These wells may monitor strata at several depths using specialty drilling equipment and well design with very discrete slotted intervals and localized bentonite packer seals. It is Wright's opinion that the initially proposed well designs are usable and that should data indicate groundwater pumping is needed for dissolved plume control installing larger diameter (4-inch diameter wells) may be needed for deep well installations for dual monitoring and pumping use. Proposed Addendum Interim Remediation and Source Removal Potential Buried Source PHS EHD indicated during our meeting that some interim cleanup is desirable at this time, with the understanding that site subsurface characterization is ongoing. The site property is very small and Wright does not desire to damage existing monitoring wells. We believe interim remediation activities must address possible buried sources to confirm or eliminate presence as described below. A magnetic survey to detect metals found anomalies that could indicate buried drums in the backfilled excavation (Ramage�))<YIOThe final disposition of excavated soils from the former tank pit is not clear from project reports reviewed. It is possible that contaminated soils and drums containing soil or ground water/product have been placed in the former excavation. If present, soils and leaking drums could be a continued source of contamination. In addition, buried drums could present a safety hazard during drilling or remediation and construction activities. Wright believes it is prudent to verify the nature of the anomalies found in the magnetic survey before proceeding with any drilling activities. We will perform a thorough file search and record review and evaluate the need for additional geophysical survey and/or hand probing to pinpoint the location of drums. Should drums be found an excavation in the former tank pit area would be required to remove and dispose of the drums before proceeding with additional well AN installatio . Page 3 of 6