A dairy is a farm or business enterprise that raises and produces milk products for human consumption from cows, goats, or other animals. Dairies produce large amounts of waste, including manure and wastewater, in small areas. Depending on management practices, these wastes can contribute pollutants such as nutrients, organic matter, sediment, pathogens, heavy metals, hormones, antibiotics, and ammonia to ground water or surface water, especially if a dairy is located on sandy soils where the depth to ground water is shallow. Poor management practices include inadequately sized and poorly lined ponds or other storage structures that allow manure or wastewater to escape into the surrounding environment, poorly maintained and unlined corrals that let contaminated wastewater seep into ground water, inadequate stormwater runoff controls, and applying too much wastewater or manure to fields too quickly or using inadequate methods. Dairies may also have aboveground or underground storage fueling tanks on site that, if not properly maintained, can impact ground water or surface water. CAFOs are agricultural facilities that house and feed numerous animals—typically cows, hogs, chickens, or turkeys—in a confined area for 45 days or more during any 12-month period.