When it comes to a spill in large quantities, milk can be treated as an oil (varies from state to state) from a response perspective and what most don’t realize is that large amounts of spilled milk is also classified as a pollutant, especially if it reaches surface waters during a spill. A large quantity of milk spilled into a body of water is also more harmful if the body of water is "still" water, as opposed to a stream or river. If the water is moving, it helps to dilute the milk more quickly, decreasing the negative effects. Milk is considered a pollutant primarily because as large volumes of milk breaks down in the water, it creates a high biological oxygen. If a spill of a large volume of milk were to occur, the response protocols are to prevent the release from entering any water body by physical methods. If the spill reached the water, regulatory agencies, both state and federal, would be monitoring for oxygen levels and could perhaps attempt to aerate the waters if oxygen levels dropped too low. Animal fats and vegetable oils, have also been considered oils under the Spill Prevention, Control, and Countermeasure (SPCC) rule based on the legislative definition of "oil" in the Clean Water Act. When milk is classified as an oil, its storage and handling is subject to certain rules, which are intended to prevent damage to the inland waters and shorelines of the United States.