SITE INFORMATION AND CORRESPONDENCE

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Mr Kirk Williams • - 2 - • 15 August 2008 Comment 4. In regards to the various analytical methods available to analyze water for 1,2,3-trichloropropane, Western Farm Service observes that a decision process for selecting the appropriate method is stated in a footnote to Table 3, and therefore specific identification of the wells that currently qualify for a method with a lower detection limit does not need to be repeated in the footnotes for Tables 1 and 2. Regional Water Board staff concur, and the footnotes have been removed. Comment 5. In the draft MRP, a footnote to Table 3 requires that concentrations that are detected below the reporting limit and above the detection limit shall be identified as trace. Western Farm Service states that the analytical laboratory identifies these values with a J descriptor, but they are not identified in the electronic data submittals routinely provided by the laboratory. Western Farm Service transfers the electronic data directly into the table. Regional Water Board staff observe that the constituents that have been detected at the site below the method reporting limit have water quality objectives that are much greater than the detection limit. Cleanup goals for constituents of concern range between background concentrations, which requires the lowest reasonable detection limit, and the water quality objectives. Therefore, Regional Water Board staff will-require that Western Farm Service identify the occurrence of values reported below the detection limit before it can determine whether a cleanup has been complete. However, in this particular case, the requirement to routinely report values below the method detection limit has been withdrawn from the Monitoring and Reporting Program for Western Farm Service's Stockton facility. Comment 6. Western Farm Service advises that in a footnote to Table 3, the draft MRP erroneously identifies the detection limit for MCPP twice and neglected to identify the detection limit for MCPA. The error has been corrected. Revised Task Schedule In its 25 April 2008 letter review of the Annual Report, Regional Water Board staff requested that Western Farm Service conduct repairs to an indentation in the engineered cap that overlies the northern pond. In Comment 1 of its Memorandum, Western Farm Service reported that since the October 2007 report was prepared, it engaged CVC Environmental to propose repairs. CVC Environmental observed that the indentation is less than one-half inch in depth and the asphalt has not cracked. It advised that adding asphalt to recontour the surface would be ineffective, and an intrusive repair patch would introduce a weakness in the cap integrity. In conclusion, the cap appears to be structurally sound and the cap will be reinspected in September 2008. Regional Water Board staff withdraws its request for repairs at this time. Western Farm Service will continue to monitor the indentation and overall cap integrity. Beneath the engineered caps of the north and south ponds, Western Farm Service will analyze subsurface soil for contaminant concentrations. In its 25 April letter, Regional Water Board staff requested a subsurface soil sampling workplan be delivered by 20 June 2008. In Comment 2, Western Farm Service requested an extension to 2 July 2008. Regional Water Board staff received theworkplan on 1 July and-conditionally concurred-with-the plan in its 12 August 2008 letter.