Modeling Alternative Treatments Systems for CAFOs in Kansas

Confined Animal Feedlot Operations (CAFOs) wastewater traditionally has been treated by running wastewater through a settling basin, temporarily storing it in a lagoon, and then applying it to a field. The EPA recently changed the CAFO regulations to allow alternative systems that treat wastewater at least as well as the traditional system (Federal Register, 2003). The alternative system can be tested with a computer simulation model over a 25-year period. A computer simulation model for Kansas for use by designers and regulators to evaluate alternate systems was developed for several CAFOs treatment systems. The CAFOs model, written in C, uses a modular system of operation with each treatment structure as a separate module. The model’s components consist of feedlot runoff generation, settling basin, vegetated treatment area, vegetated infiltration basin, lagoon, and field application treatment structures. The modular format allows the user to simulate different treatment arrangements.