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The data shows a decrease in chlorides as well as total dissolved solids from thirty feet to seventy feet in wells #7 and #1A. An increase, however, occurs from seventy feet to one hundred feet in wells #7A and #7B. It is suspected tha, the forty foot thick, dense silt layer, described in the Beneficial Use and Remedial Action Report, has acted as a filter, concentrating the salt at this depth. Soil samples taken during the construction of well #7B were presented in the Beneficial Use and Remedial Action Report (B.U.R.A. ) and seem to support the concept that the salts are being concentrated in the silt layer. Both soil salinity and chloride analysis reveal levels in the silt layer that are significantly higher than the formations directly above or below. (Please see appendix A, B.U.R.A. August 1989) Water samples collected from monitoring well #7B revealed electrical conductivities of 3500 umhos/cm, a chloride level of 1039 mg/l , and a TDS concentration of 2200 mg/l . As previously noted, these results are higher than those found in well #7A at seventy feet. We believe that consideration should be used when reviewing this data because the monitoring well is screened from one hundred thirty feet to one hundred forty feet. As a result, this water may be - greatly influenced by the concentrations of contaminants within the soil of the silt layer and may not represent the true status concentrations in Lhe water at the formation directly below the silt strata. Implementation of the brine recycling system has been awaiting the Regional Boards approval of remedial action recommendations. The brine recycling system design depends on the volume of brine requiring treatment and at least one of the recommendations describes treating extracted contaminated ground water with the system. As of this date several heating experiments have been completed with the brine to determine the necessary design required for efficient reconcentration. It is the engineers opinion that organic removal and concentration of the brine is the best procedure found to date. The concentrated brine would be recycled into the hide stabilization process. A firm specializing in aquifer performance tests has been contacted and is scheduled to examine the Southwest Hide property this week. This site examination will reveal whether or not additional drilling will be required to perform the pump test. Determination of the aquifer transmissivity and vertical continuit will be achieved by this test. Arrangements are being made for the removal of the pump from the Southwest Hide production well . A special camera will be used to examine the integrity of the old steel casing. This work has been scheduled for mid-January. Information on the condition of the casing and the depth of perforations is necessary to determine the usefulness of this well with respect to the aquifer performance test. Vertical extent of the plume can be examined by means of additional monitoring wells that reach to greater depths. An additional well is recommended to a depth of at least one hundred fifty feet in an attempt to get below the dense silt layer found in monitoring well #7B. The perforations in the casing of this well should not extend upward into the silt layer in the hopes that a water sample can be collected that is more representative of the water below the silt layer, which will hopefully be free of a high salt concentration.