By following the elements of the rigorous evaluation prescribed in the certification requirements and by conducting the necessary operation and maintenance to achieve no discharge, the operator will be able to demonstrate that the CAFO is designed, constructed, operated, and maintained such that a discharge will not occur. In the event of a discharge from a properly certified CAFO, the CAFO will not be liable for prior failure to seek permit coverage. The CAFO, however, remains liable for discharging without an NPDES (National Pollutant Discharge Elimination System) permit. Only CAFOs with NPDES permits can invoke the “upset and bypass” defense provisions of the NPDES regulations.