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Pathogen contamination of waterways is a serious concern in dairy farming areas where livestock waste is applied to agricultural fields. As an alternative, a biodrying composting system dries collected livestock waste, reduces the strong odors, and has been proposed as a means of reducing, and even eliminating pathogens present in the waste. Therefore, the survival of pathogens in a biodrying composting system was investigated. Dairy farm livestock waste was piled in a biodrying storage shed where forced aeration and natural decomposition processes heated a major portion of the waste pile to temperatures exceeding 55°C. Ascaris suumeggs were used as the surrogate species and inoculated into special chambers and placed at three different elevations at different intervals along the length of the pile. Control chambers were stored in water at 4°C in the laboratory. Both compost and control chambers were removed at Day 4, 8, 12, 16, and 20. The eggs were extracted from the chamber medium and analyzed for viability. No viable eggs were recovered from any of the chambers removed from the compost pile, while ≥90% viability was observed in the control chambers. High temperatures and continued drying were the major contributing factors to the inactivation of the helminth eggs. The complete inactivation of A. suumeggs by the biodrying process encourages the storage and treatment of manure to high temperatures and reduced moisture conditions before field spreading to reduce the risk of harmful pathogens contaminating waterways and potential drinking water supplies.

Preferred movement of chloride and nitrate during runoff events following nutrient application was studied experimentally on 109 m long fields with a hard pan at shallow depth near Ithaca, NY. Chloride and nitrate applications were surface‐applied and incorporated at 36 and 69 m uphill from the collection point. All of the applied chemicals, when surface‐applied on saturated soil, were completely lost in the surface runoff and interflow water. When incorporated, at most 60% of the mass applied was lost. The fraction lost appeared to be related to the initial moisture content of the soil. After a chemical application, the concentration in both runoff and interflow was initially high and then decreased exponentially. The concentrations in the runoff water, interflow, and macropores were approximately equal throughout a runoff event.