SITE INFORMATION AND CORRESPONDENCE

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Mr. Ben Hall - 3 - 17 September 2004 Musco Family Olive Company Company, prepared by Joseph Drago (Kennedy/Jenks) and Anne P. Cavazos (RG No. 6425). Regional Board staff is currently reviewing the report for adequacy. I contacted Michael Campos for clarification of this request. He indicated Musco's extension request pertains to the characterization of groundwater quality in the vicinity of the proposed reuse areas. While it is preferable for reports of new discharges to land to characterize the quality of groundwater in the vicinity of the proposed discharge, it is not necessary to complete this off-site characterization for the report required by Provision G.2.j to be determined complete. Work conducted to characterize off-site background groundwater quality should, however, be performed timely and in concurrence with Regional Board staff. Prior to installing groundwater monitoring wells specific for this purpose, Musco should submit a technical report describing the location and design of said wells prior to their installation, as described at the end of this letter. Key Comments on Proposed Onsite Treatment&Storage and Offsite Discharge. In general, while the RWD proposes to substantially reduce the discharge's TDS, sodium, and chloride concentrations, it proposes to reduce its BOD concentration to a level slightly higher than that provided by conventional secondary treatment. If Musco is requesting the offsite wastewater discharge be approved as a recycled water project, it must subject the discharge to at least secondary treatment. The discharge of effluent containing higher BOD levels would be regulated via WDRs issued to the user, as it must rely on soil treatment processes to reduce the discharge's organic content to levels that minimize the potential for groundwater degradation from decomposition byproducts (e.g., manganese, iron), hardness, and alkalinity. Additionally, the RWD proposes to commingle in the 84-mg reservoir highly treated wastewater with essentially untreated wastewater(BOD in excess of 900 mg/L) for additional treatment. As explained in the enclosed memorandum, this proposal has the potential for degrading shallow groundwater from, at a minimum, decomposition byproducts, hardness, and alkalinity. Accordingly, best practicable treatment and control measures must be implemented to ensure the discharge is consistent with State Water Resources Control Board Resolution No. 68-16. In our judgment,Musco can either equip the reservoir with a liner adequate to preclude waste constituents from entering shallow groundwater, as is specified by Task 16 in Time Schedule Order No. R5-2002-0014-ROI, or treat all wastewater to secondary standards prior to storage in the reservoir discharge and implement effective measures to minimize the accumulation of sludge on the reservoir's bottom. In any event, Musco has not provided sufficient information to justify it has met the requirements, if not the intent, of Task 16. Resolution of this matter, which will be addressed under separate cover, can be accomplished through the implementation of a tracer dye study. Based on limited data,the RWD preliminarily characterizes offsite groundwater quality, which is necessary to establish target TDS, sodium, and chloride concentrations in the discharge. An expanded data set is necessary to characterize offsite groundwater quality. The RWD refers to groundwater monitoring wells recently installed by Musco in the proposed recycled water use areas. Documentation regarding the design and installation of these wells should be presented to the Regional Board in the form of a technical report containing information identified in Enclosure B. As the report involves work requiring interpretation and proper application of engineering or geologic sciences, it must be prepared by or under the direction of persons registered to practice in California and bear the signature(s) and seal(s) of the registered professional(s)in a manner such that all work can be clearly attributed to the professional responsible for the work. Continued Discharge to Existing Land Application Fields. The enclosed memorandum addresses several issues regarding Musco's proposed ongoing onsite discharge. In many respects,the RWD appears to downplay or even dismiss the impact of Musco's ongoing discharge on soils and shallow