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ATTACHMENT \l , Pages 35-36: Shallow soil and deep soil boring samples will be collected from the pond areas. It is proposed that the surface sample and the 40 foot boring sample will be analyzed for total concentrations of the selected metals. All other soils will be analyzed for soluble concentrations. Because soluble concentrations are to be analyzed to determine the threat to water quality, the 40 foot sample should be analyzed for soluble concentrations and not total concentrations. The determination of insitu soluble concentrations of metals will indicate whether the contamination is at designated or non-designated levels. All four closure alternatives involve leaving some contaminated soils in place. Therefore, the designated level for soils at this site must be determined. Attached is a paper detailing the designated level methodology which should be used to determine the cleanup level as part of closure. Pages 35-36: The proposal includes collecting soil samples at 0-0.2 feet, 2.0- 2.5 feet and 4.5-5.0 feet in each shallow boring in a transect pattern across both pond areas. If the analyses for soluble concentrations indicate that contamination has extended beyond five feet in depth, additional borings to further define the vertical extent may be required. Considering the historical volumes of wastes disposed of to land especially in the drainage area south of the galvanizing building and in Pond 1, and based on Figures 12 to 15, it may be advantageous to sample at 10 feet rather than at 2.5 feet in depth. Page 37: The plan includes trenching in an attempt to locate a dry well in the former laboratory disposal area. Soil samples are to be collected from the base of the trench. Depending on the depth of the trench and if the samples are to be manually collected, the trench must contain shoring. Page 37: Soils from the borrow area are to be compacted for permeability testing. The samples will be compacted using ASTM Method D1557 which is the modified proctor and which requires more compactive energy (18 inch drop, 10 pound hammer, five layers) than the standard proctor (12 inch drop, 5.5 pound hammer, three layers). Use of the modified proctor over the standard proctor to establish design criteria for cap and liner permeability may need to be reconsidered in relation to the type of compaction equipment to be used in closure. Page 37-38: The borrow area to be located in the field in the western portion of the site must not be taken from the disposal areas for muds, cuttings or water. Pages 37-38: Permeability tests must also be performed on the clay liner and cap ( if installed) or on a test pad using the same materials and design criteria as the liner or cap. The density of tests per area and per lift must be specified. Pages 37-38: The geotechnical testing did not include tests for Atterberg limits, grain size distribution or moisture content. These tests should be performed to establish a data base for the on-site soils and for quality