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I in 100 wet year is 8.7 inches on the 42 acres to be used for winter wastewater application. This compares favorably to the range of values for wastewater application recommended by Kleinfelder in 1984 based on soils tests. It also compares favorably with an estimated clean water permeability of 0.2 inches per hour (150 inches per month) by the Soil Conservation Service for the Vignolo silty clay loam (new survey, not yet published) found over most of fields 1, 2, and 3. It should be noted that only 1 inch of wastewater would be applied to the fields, and this would require only six hours per month of sprinkler operation on the entire 42 acre area. Emergency Storage Pond , During November through May, wastewater will not be applied to the fields during and for 24 hours after a rainstorm. When wastewater cannot be applied to the fields, it will be stored and treated in the emergency storage pond. If the storage pond becomes full , all wastewater generating operations will cease until land application can be resumed. The storage pond has a volume of 540,000 gallons and a total surface area of �u 11,200 square ft (1/4 acre) at a depth of 10 feet. With an estimated 3 feet( of dead storage due to aerator limitations and 2 feet of freeboard, the k ��/ available storage volume is 455,000 gallons. At 40,000 gpd, this would hold —� wastewater from eleven days of operations, which would correspond to fifteen calendar days. During dry weather, the storage pond will be emptied completely and then refilled to a depth of 3 feet with clean water. The storage pond is lined with 36 mil Hypalon to facilitate residual solids removal . Mechanical aeration will be provided to maintain aerobic conditions in the storage pond and prevent odor generating conditions. Aeration design will be based on mix or aeration limiting criteria and will be for an organic loading rate of 440 lb BOD/day with a hydraulic loading rate of 75,000 gpd. The required aeration to treat essentially all the incoming BOD would be 15 horsepower minimum (@ 1.5*BODS, 1.8 lbs 0,/hp-hr) . Eight horsepower would be the minimum power required to suspend solids (@ 15 hp/Mgal ) . In order to meet these requirements and provide a margin of safety, 20 horsepower of aeration capacity will be installed. Aeration will be accomplished with adjustable angle floating aeration units set at 35 degrees from horizontal . The aerators will be automatically shut off when the pond is drawn down to a depth of 3 feet to prevent damage to the liner. SHALLOW GROUNDWATER NITRATE AND SALINITY IMPACTS As was stated in the Report of Waste Discharge, there should be no significant increase in nitrate levels in shallow groundwater as a result of QAP wastewater disposal practices. It was also pointed out that shallow groundwater nitrate concentrations were in excess of the 45 mg/L drinking water limit before QAP operations began and have not changed significantly since that time based on monitoring well data. 5 RP102-0