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Ms.Nancy Bishop - 2 - 14 October 1999 laboratory returned the analytical results, which could be two to three weeks after the sample had been taken. During this initial start-up period, please have the laboratory run the weekly constituent analyses on a three-day turn-around time. The Design Summary proposes to provide a report describing the installation, operation and monitoring data. This operations report is due by 30 December 1999. Capture Zone Analysis The NPDES Permit No. CA0084484 issued to Western Farm Service in Vernalis allows discharge of groundwater to West Stanislaus Irrigation District's Lateral 4 North provided that electrical conductivity in the canal does not exceed 700 umbos/cm, among other restrictions. Conductivity in the Lateral exceeded this threshold for most of the months of the irrigation season this year. As a result, WFS has not discharged to the L atcral. is anticipated that there will be a two-month opportunity to discharge up to 60 gpm into the canal at the beginning of the Year 2000 irrigation season. The NPDES Permit requires a capture zone analysis to be submitted by 1 December 1999. During a 5 October 1999 telephone conversation with Carolyn Kneiblher and Stephen Lathrop of GeoSyntec, they requested a delay of the capture zone analysis work until the beginning of the Year 2000 irrigation season, when the extraction pump is expected to run at the maximum allowable discharge rate. GeoSyntec agreed to provide me with a letter detailing this request. When the NPDES permit was written, it was not foreseen that discharges to the lateral would not be possible for the majority of the irrigation season. I agree that the most economical time to do the field work for the capture zone analysis is in March 2000 when conditions in the Lateral may allow for the discharge of groundwater in accordance with the Permit conditions. Therefore, the capture zone analysis work may be performed in the spring of 2000, with a report of results due by 30 June 2000. This report shall also discuss the effectiveness of the combined discharges to make-up water and the Lateral to contain the plume, and make recommendations for additional containment and treatment, if warranted. If discharge to the Lateral is not possible in the spring, please schedule a meeting with Board staff to consider alternate strategies, and the report due 30 June will discuss recommended remediation alternatives. I;yu ve an uest'ons, you may call me at (916) 255-3080. ERRELL Site Cleanup Unit cc: Mr. Stephen Lathrop, GeoSyntec Consultants, Walnut Creek Ms. Carol Oz, San Joaquin County Public Health Services, Stockton Mr. Frank Fossati, Shell Oil Company, Lake Forest Mr. Fred Strauss, Western Farm Service, Vernalis