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4.) The wastewater system consists of a mechanical separator, a holding pond and a smaller separation pond. A particular percentage of the nitrogen entering this system will certainly volatilize in the form of ammonia and be adsorbed onto the clay soil particles lining the ponds. Ammonia volatilization occurs from urine, manure wastewater transfer to the ponds and during pond storage. Both ponds were hydrometer tested for clay content in August, 1995 in compliance with Regional Water Quality Control Boards requirements. Clay content in both ponds was determined to be over 42%; consequently, there is adequate clay to sufficiently "bind" ammonium molecules and thus preventing the conversion to nitrate. The ponds can also be considered anaerobic. An aerobic environment is required for this nitrate conversion to take place. This can only take place if the ponds were allowed to dry out. It is important that when the manure in the ponds is eventually cleaned-out or draglined, that it be done as soon as feasible after the water is pumped out to prevent this conversion from taking place. An investigation by Sutton, et al (1983) suggests that a nitrogen loss from a lagoon or pond liquid system can range from 70% to 80%. The second issue regarding the ponds is the natural process of denitrification. This process takes place only in anaerobic environments such as saturated clay soils where the pore space volume is extremely small and can account for a 15% to 20% nitrogen loss. It has been our experience that nitrate concentrations in groundwater around wastewater holding ponds is comparatively low in high clay content soils. 5.) Upon separation of the wastewater from manure solids by the use of a mechanical separator, some of the solids are stockpiled on a concrete slab. However, there is manure overflow onto the soil in this area. The manure stacked on the soil can create a "point-source" of nitrate conversion and infiltration into the underlying soil. Fortunately, the manure turnover in this area is rapid so in essence, there may not be enough time for conversion to take place. The total nitrogen excreted from the animals has been historically difficult to quantify since the rates of several important nitrogen transformation processes such as ammonia volatilization and denitrification are unknown. The following calculations incorporate the use of animal units to formulate the waste loading. The animal numbers are approximate and represent values toward the upper range: 7