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INFORMATION SHEET • • - 12 - MUSCO FAMILY OLIVE COMPANY AND THE STUDLEY COMPANY WASTEWATER TREATMENT AND LAND DISPOSAL FACILITY SAN JOAQUIN COUNTY Based on the above analysis, staff have proposed an interim background concentrations for TDS (2,047 mg/1), sodium (597 mg/1), chloride(601 mg/1), and nitrate-N(6 mg/1). The Discharger is required to install and monitor additional groundwater monitoring wells onsite, and within two years to propose final background concentrations. To protect groundwater quality, the WDRs contain effluent limitations that match the background water quality. Musco is currently discharging waste at a higher concentration that the TDS and sodium effluent limitations. Therefore, the Board is asked to consider a companion Cleanup and Abatement Order. The C&A provides a time schedule for Musco to reduce the TDS and sodium in its effluent. Musco must meet the effluent limitations within two years. Staff expect that the final background water quality values, and hence the final effluent limitations, will be less than the interim values. Therefore, once the final background water quality study is completed, it is expected that Musco will need to further reduce the salt in its effluent beyond what is currently required by the C&A. These WDRs require continued groundwater monitoring to fully evaluate the impacts of the Discharger's past and future disposal practices. However, it is not appropriate to follow the Discharger's recommendation to conduct a year of monitoring to determine if there are groundwater impacts, and then design effluent limits based on the groundwater data. In the last year, the Discharger has substantially increased its wastewater flow and strength, and has begun applying wastewater to a larger area. These recent changes may not yet be reflected in the groundwater quality. In addition, the RWD clearly shows that the Discharger intends to apply significantly more salt than will be taken up by the crops; therefore, these WDRs contain limits to prevent impacts to the underlying groundwater. Shallow soil samples were collected in the land application areas in November 1999 and April 2001 as part of the 6 April 2001 Soil Salinity Assessment required by C&A Order No. 5-00-717. The samples were collected to evaluate the wastewater application impact to soil quality. Analysis indicted that 22-percent of samples collected in the Field 55 East and Field 55 West (55 acres total)may be impacted by the wastewater application and 28-percent of the samples collected in Field 95 (95 acres) may be impacted. The report stated that the high concentration of sodium in the wastewater has the potential to reduce the already low permeability of the soil permeability. Pan lysimeters are required to allow measurement of percolate quality. If percolate quality is worse than background groundwater quality, additional source control or better cropping will be required. APPLICABILITY OF WATER RECLAMATION REQUIREMENTS Musco has requested that the Regional Board should consider Musco's discharge under the"Water Recycling Law", beginning with Section 13500 of the Water Code. This request was contained in the Discharger's 8 August 2002 Comments to the Tentative Waste Discharge Requirements. Musco believes that its wastewater should be declared`reclaimed water" and as such, water reclamation requirements,not waste discharge requirements, should be issued. Musco further states "a Regional Board may not deny issuance of water reclamation requirements to a project which violates only a salinity standard in a basin plan." Staff have considered this issue and have consulted with the State Board Office of Chief Counsel. It is our understanding that it is not appropriate to regulate Musco's discharge under the Water Recycling Law and that the most appropriate vehicle for regulation is these waste discharge requirements. Although not expressly described in the this section of the California Water Code, "recycled water" typically applies to domestic wastewater which is treated to an extent that it can be beneficially reused,