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Three factors are of significant importance regarding nitrogen contribution and the mitigation of the potential for nitrate impact from the open corrals. The first mitigating factor concerns the sloping of the open corrals to manage rainwater runoff. Each of the corrals are sloped 4%to 6% from the center to the ends to promote rainwater runoff. This water management technique reduces percolating water through the soil profile, thus preventing the creation of a hydraulic head to carry nitrate molecules downward. Since the open corrals are not composed of a sandy material, precipitation data will not be considered as a hydraulic force. The second factor for alleviating nitrate impact is the clay content. The clay content of the soil in the corral areas was determined to be 42%to 47% clay by the hydrometer test. In addition, a permeability test was also conducted on representative samples taken from the open corral areas. Test results indicate the indigenous soils possess a hydraulic conductivity, k, of 2 X 10'' cm/sec. This can be considered an extremely low soil permeability. By using an average water table, or zone of saturation depth of 16 feet below grade, the following calculation illustrates that it will theoretically take 77 years before a nitrate laden wetting front reaches the saturated zone: 2 X 10' cm/sec. X 60 sec/l min X (525,600 min/year-30.5 cm/R)= 0.207 ft/year. 16 ft - 0.207 ft/yr= 77 years. Due to this high clay content soil, the denitrification process will be expected to predominate in the subsurface anaerobic conditions. Located in the Appendix, is a Soil Analysis Report for soil taken from the open corrals in various locations. The sample number OCO-6 represents open corral 0-6 inches in depth, while the 30-36 represent that sample from that depth. The significant components of this data are organic matter(O.M.), pH, Cation Exchange Capacity(CEC), nitrate and Total Kjeldahl Nitrogen (TKN). All of these parameters play an important role in nitrate formation and the denitrification process. The potential for nitrate development is present due to the high TKN; however the O.M. which is low at the time the samples were taken, but will increase will create conditions favorable for denitrification. Additionally, the low nitrate present, the alkaline soil and the high CEC are all favorable for denitrification. The third mitigating factor is the soil compaction from the animals. The hooves of the cows act essentially like a "sheepsfoot" soil compactor, creating a high density, low void space soil "cap" in the top six inches of the soil profile. Soil compaction attenuates the downward migration of nitrate molecules by reducing pore water permeability. Estimated nitrate nitrogen loading from the manure and wastewater will be discussed in Part 5 of this Section. 6