"Process wastewater" means water directly or indirectly used in the operation of the animal feeding operation for any or all of the following: spillage or overflow from animal or poultry watering systems; washing, cleaning, or flushing pens, barns, manure pits, or other animal feeding operation facilities; direct contact swimming, washing, or spray cooling of animals; or dust control. Process wastewater also includes spent foot bath water and any water that comes into contact with any raw materials, products, or by products including manure, litter, feed, milk, eggs or bedding.
130 Neb. Admin. Code, ch. 1, § 041