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0/LDC -3- 13 July 1987 It was agreed that EC, pH, TDS and any contaminants detected in on- site monitoring wells should be analyzed in off-site well waters. Ground Water We commented that wellhead reference point elevations reported to date are very inconsistent. There is an apparent shift in the gradient of over 900. JHK maintains that the survey problem has been rectified, and that there is no shifting gradient when calculations are made on the baseline survey map. It was agreed that this conclusion would be discussed at a later date, and that accurate maps showing well locations, depth to water measurements, static water surface elevations, reference point elevations and water table gradient for each monitoring period would be included in the HAR. Deeper wells must be drilled to fully define the vertical extent of the uppermost water-bearing unit and the contamination therein. If the bottom of the uppermost water-bearing strata is found to be contaminated, analysis of the next underlying water-bearing unit may be necessary. Deeper wells are also necessary to determine vertical components of ground water flow. Little agreement was reached on the need for additional wells. A well will be constructed immediately below the SI after excavation of the wastes. The possibility of perforating this well throughout the entire thickness of the upper water-bearing unit and using packers to take discrete samples was discussed. It was reported that the ongoing ground water monitoring program has been expanded, as of April 1987, to include EC, TS and standard minerals. Slug tests, along with lab permeability tests, are proposed for determination of the aquifer hydraulic conductivity and storage coefficient. The limitations of these tests were discussed. The usefulness of pumping tests was discussed, as was the problem of disposal of contaminated water from such tests. No agreement was reached on methods of defining aquifer properties. Monitoring System It was agreed that grain size analysis would be run on aquifer materials from the monitoring wells to justify screen slot size and filter pack choices. A composite sample of the screened interval will be used for this analysis.