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Mr. Salazar inquired if DTSC will require that the groundwater plume be brought back to the <br /> maximum contaminant levels (MCLs)with respect to trichloroethane (TCA) and vinyl chloride <br /> (VC). Mr. Austreng replied that the regulatory agencies have not yet received the document. Mr. <br /> Fennessy stated that VC was measured at one ppm in the groundwater down to the third aquifer. <br /> There were no TCA concentrations; there were minor concentrations of TCE. <br /> Mr. Fennessy stated that the,draft RI will be submitted in December. Comments will be <br /> addressed in a draft final, followed by the FS and the ROD.Mr. Beeman stated that this is an <br /> extended period of time. Ms.Huey stated that the document can be made available to any <br /> interested individuals. Mr. Austreng encouraged attendees to call with any questions. <br /> Mr. Fennessy stated that any immediate threats to human health or wildlife are handled using a <br /> time-critical removal action. <br /> Mr. Suntag inquired why the cap was the presumptive remedy. Mr. Fennessy replied that the <br /> remedy has not yet been decided upon. It was assumed that the top of the landfill cell was to be <br /> removed or capped to prevent exposure. <br /> Ms. Huey explained that prior to the RA,the Data Quality Objectives (DQOs)were established. <br /> This required naming a remedy to determine the sampling design. EPA concluded that the results <br /> of various remedies were equal and suggested a cap for a municipal landfill. Mr. Austreng stated <br /> that DTSC voiced its disagreement with this; Ms. Schwab concurred. The RI data will identify <br /> data gaps and will also help to determine which remedy is appropriate. <br /> Ms. Huey stated that OU-1 consists of 21 non-landfill sites located on the opposite side of the <br /> island. Ms. Schwab noted that these sites consist of warehouse areas and a burn area. Ms. Huey <br /> added that they also involve drain lines, sumps, a building that was demolished due to a pesticide <br /> source, and a road on which oil was sprayed to control dust. The Navy is currently reviewing the <br /> pre-draft report which will be sent to the regulatory agencies in January. <br /> Ms. Huey stated that OU-4 consists of 10 sites which were discovered during a review of aerial <br /> photographs (Ms. Huey and Mr. Fennessy pointed out the sites on the map). Samples were taken, <br /> and further investigation was necessary. The field work is complete and an RI report is being <br /> prepared. Ms. Schwab added that in addition to the Comprehensive Environmental Restoration <br /> Compensation and Liability Act(CERCLA),the Water Board is working with the Navy in <br /> regard to cleanup of underground storage tanks (USTs) and the oil/water separators. The drainage <br /> ditches have been excavated; Ms. Huey stated that confirmation samples will be taken to <br /> determine the chemicals detected in the native soil. <br /> Ms. Schwab added that the two aboveground storage tank areas are no longer owned by the <br /> Navy. Mr. Fennessy stated that there is higher surface water on three sides of the island, resulting <br /> in inward groundwater gradient. The surface water in the Stockton Deep Water Channel also <br /> flows inward, or west. There is flat gradient in the center and steeper gradients on the outside of <br /> the island. <br /> 5 <br />