SITE INFORMATION AND CORRESPONDENCE

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INFORMATION SHEET MUSCO FAMILY OLIVE COMPANY AND THE STUDLEY COMPANY WASTEWATER TREATMENT FACILITY SAN JOAQUIN COUNTY Discharger has stated that it will no longer apply wastewater over the leach lines or seepage pits, and this Order contains a Prohibition to that effect. GROUNDWATER/SOIL CONDITIONS The Discharger constructed a groundwater production well in 1983. The well is approximately 607 feet deep with a sanitary seal from the surface to 50-feet below ground surface. The gravel pack exists from 50 to 607 feet below ground surface. Based on five sample events performed from 1982 to 1999, the water quality in the well is poor with total dissolved solid concentrations averaging 1,513 mg/L, sodium 372 mg/L, and chloride 334 mg/L. Agricultural,domestic, and industrial wells located within two miles of the site were surveyed and the available data indicates they also contain poor quality groundwater. Thirteen groundwater monitoring wells were installed in March and April 2002; one existing well was redeveloped. The wells were sampled in April 2002. Shallow and deep zones of groundwater were identified in the investigation. The depth to groundwater at the Discharger's facility is dependant on the well location. Monitoring wells with shallow groundwater are in low land areas or in close proximity to the surface drainage course. Wells with deep groundwater are typically in higher topographic elevation areas further away from the surface water drainage. Depth to groundwater varied from 14 to 175 feet below ground surface. Land surface elevations vary from 259 to 443 feet above mean sea level. Groundwater flow directions generally mimic the topography. Overall the flow direction is to the northeast, however,topographic variations can significantly change the local flow direction. While the Discharger has shown that local groundwater is of generally poor quality,the on site monitoring wells show that the Discharger's activities may have •impacted the underlying groundwater. The Groundwater Monitoring Well Installation Report identified the chemistry of the groundwater in the shallow and deep zones as distinctly different,with shallow zones tending to have higher concentrations of sodium, chloride, and total dissolved solids. As the Discharger has not provided other groundwater data regarding the quality of groundwater, or a more comprehensive database of source water, the data may be presumed to be representative of the quality of background water in the underlying aquifer. Absent information to the contrary, it must be assumed that shallow aquifers are in hydraulic continuity with deeper zones. Data substantiates that underlying groundwater is of poor but useable quality. 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