SITE INFORMATION AND CORRESPONDENCE

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Port of Stockton - 2 - 23 August 2005 Bulk Terminal Site c. Metropolitan Stevedore Copper Concentrate Transfer Area Per Figure 5, soil-boring C-12 is located outside the transfer area. To obtain adequate appraisal of soil impacts the boring should be moved to a location within the transfer area. 2. Section 3.1.2.2 Boring Advancement The report states for each boring the first groundwater samples will be taken at the first"at least two feet thick and to consist predominantly of sand or silty sand"unit. The first layer with this characteristic is estimated be no more than 30 feet bgs. This means that the first groundwater sample would be approximately 25 below the groundwater table. This is not consistent with protecting the beneficial uses of all groundwater. Therefore, groundwater samples from borings (C-3, C-4, and C-12)to evaluate the impacts from stockpile and transfer areas should be collected from first groundwater. In borings (C-7, C-8, C-10, and C-11) designed to determine whether a facility (H.J. Baker, Petroleum coke and coal area, etc.)has impacted groundwater both the first groundwater and first two-foot sandy and sandy silt unit should be sampled. Based on the existing data it is unclear whether potential groundwater pollution will be more mobile in uppermost groundwater or in the first two foot sandy unit. 3. Section 3.1.3 Task 3 — Sample Analyses a. Soil Analytical Methods In general we concur with the soil sampling and analyses plan. However, staff believes Title 22 metals analysis should be done on all soil samples to achieve a more comprehensive result. Soils from one area can then be compaired to soils from other areas and to groundwater samples. Arsenic analysis should be U.S. EPA Method 7062 and Nickel analysis.U.S. EPA Method 7421. The report proposed to analyze metals by the DI WET extraction method. Many of the soils and most surface water sampled during March 2005 inspections were acidic and DI WET extraction would not be appropriate. Based on the soil samples pH results, if the pH is low the citrate extract is required if neutral, DI-WET could be used. b. Ground Water Analytical Methods The first round of sampling of well and soil boring water samples should be more comprehensive than what was proposed in the report. This would allow a better comparison of one water sample to another, and comparison of soil samples to water samples. This extended sampling list will also allow an evaluation of the overall groundwater characteristics. In the future the water analysis constituents may be greatly reduced. For the initial investigation all groundwater samples should be analyized for the following: bicarbonate, calcium, magnesium, sulfate, sodium, nitrate, chloride, sulfur, copper(use U.S. EPA Method 7062), nickel (use U.S. EPA Method 7421), vanadium, Title 22 metals, pH, TDS, alkalinity, EC, TEH, BTEX and PAHs.