Concentrated animal feeding operations (CAFOs), also known as factory farms, typically house thousands of animals, generating millions if not billions of gallons of animal waste per year.  <...> Animal waste is stored either in pits or in open ponds, called lagoons. Such waste-containment areas often leak and, during large storms, can rupture. To dispose of the waste, CAFOs spray this manure onto farm fields. The environmental damage from spraying and from leaking, ruptured lagoons can be devastating. Surface and groundwater contamination (serious threats to aquatic ecosystems) and excessive nitrates in drinking water (serious threats to public health) stem from CAFO pollution. Animal waste can also include pharmaceutical residues, heavy metals (like copper and zinc) and harmful bacteria, which can leach into water supplies.