SITE INFORMATION AND CORRESPONDENCE

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CLEANUP AND ABATEMENTS s ER NO.R5-2004-0704 J 2 THE WINE GROUP,INC. FRAN21A WINERY SAN JOAQUIN COUNTY 9. All process area stormwater and facility wastewater drains to two sumps, from which it is pumped to the vineyards for land application. The waste is treated passively by the land and/or taken up by the crop. 10. From 1935 through 1995,process wastewater was discharged to a series of percolation/ evaporation (P/E)ponds located south of the paved portion of the facility. 11. In 1995, the Discharger began discharging the wastewater directly to the vineyard. At that time, the P/E ponds were filled in and planted with grapes. 12. In 2002, a portion of the former P/E pond area was converted into a 12.6 acre-foot emergency discharge reservoir where process wastewater and storm water can be diverted during high-flow or emergency situations. 13. Wastewater is currently applied in an alternating fashion to a network of 3-foot wide by 2-foot deep furrows that are plowed between the rows of vines. Between applications, the furrows are allowed to dry and are then disked and reconstructed prior to the next wastewater application. 14. During the irrigation season, the volume of wastewater applied to the vineyard is typically augmented with well water in order to meet the irrigation demands of the crop. The well water is applied through a drip system. SOIL AND GROUNDWATER CONDITIONS 15. Site topography is flat and level, and site soils are predominantly sandy loams. Soil permeabilities range from moderately-rapid to rapid,with rates of water intake ranging from 1.5 inches to 3.0 inches per hour. 16. Three groundwater monitoring wells(MW-1, MW-2, and MW-3) have been constructed on the site. The total depth of MW-1 and MW-2 is reportedly approximately 80 feet below ground surface (bgs), with screened intervals between 50 and 80 feet bgs. The total depth of MW-3 is approximately 56 feet bgs, with a screened interval between 35.5 and 55.5 feet bgs 17. The first encountered groundwater below the site ranges from approximately 40 to 45 feet bgs. Groundwater flow direction is generally to the northwest, with an average gradient ranging from 0.001 to 0.005 ft/ft. MW-1 and MW-3 are considered to be hydraulically downgradient of the process water land application area and MW-2 is considered to be the most upgradient of the wells. However,because MW-2 is within the land application area, it may not be completely representative of true background conditions. 18. The groundwater monitoring data collected to date indicate that concentrations of dissolved solids often associated with winery wastewater are elevated in the two downgradient monitoring wells as compared to concentrations in the upgradient monitoring well. The average electrical conductivity, total dissolved solids, fixed dissolved solids, sodium, magnesium, chloride, and sulfate concentrations in the downgradient wells range from two to fifteen times higher than in the upgradient well. The data also indicate that nitrate concentrations in one downgradient well, MW-1, are approximately eight times the upgradient concentrations and five times higher than the