SITE INFORMATION AND CORRESPONDENCE

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Mr. Kirk Williams • - 5 - • 25 April 2008 The new laboratory does not appear to include 1,2,3-TCP in its fumigant analytical suite (EPA 504.1). A discussion of these limitations follows. Water Quality Objectives The compounds of bromacil and 2,4-D appear at concentrations below the applicable water quality objectives. For these compounds, Western Farm Service requests that they be removed from the analytical program. While these constituents are below their respective water quality objectives, the cleanup goal for groundwater ranges from background concentrations up to the water quality objective. Since these constituents are not naturally occurring, Regional Water Board staff cannot dismiss them as constituents of concern. Prior to 2004, bromacil, a carbamate/urea compound and 2,4-D, a chlorinated herbicide, were identified at concentrations of about 2 ug/L, more than 10 times lower than their water quality objective of 70 ug/L. After 2004, bromacil was not included in the analytical suites, and the detection limit for 2,4-D was raised to 5 ug/L. In our 15 February telephone conversation, Regional Water Board staff and GeoSyntec Consultants agreed that we would assume that bromacil is present in the wells it has been observed in the past (MW-2, MW-14A, and MW-6) and Western Farm Service will specifically analyze for bromacil in these wells and in MW-8 when the MRP is revised again. Similarly, a lower detection limit for chlorinated herbicides will be required before Regional Water Board staff can determine that the compounds are not present. Some of the monitoring wells contain sufficient concentrations of 1,2,3-TCP to warrant using a less expensive analysis than the low-level method. Paper Reduction Several changes have been proposed to the reporting format to address GeoSyntec's request to reduce the size of the semi-annual reports. The most recent five years of monitoring data should be tabulated in the report, and the entire cumulative monitoring data may be submitted in a spreadsheet on electronic media. The format of the spreadsheet should be to facilitate data transfer into a database. In addition, the laboratory data reports and field logs may be provided on electronic media. SCHEDULE In a 25 March 2008 telephone meeting with Ms. Carolyn Kneilblher and Mr. Arnab Chakrabarti of Geosyntec the following schedules were agreed upon: • By 6 June 2008, please provide comments on the attached draft Monitoring and Reporting Program. • By 20 June 2008, Western Farm Service will provide a work plan to obtain vadose zone soil samples from beneath the north and south ponds and groundwater water samples from beneath the south pond. Care shall be taken to not disturb the integrity of the pond caps and liners.