There are two types of grease disposal.
Waste vegetable oil is the spent vegetable oil from a facility's deep-fryer. When a restaurant changes their vegetable oil the old oil is put into a receptacle outside. Waste Vegetable Oil haulers are commonplace as the oil is a paid commodity. Waste Vegetable oil is recyclable for future biodiesel use and is commonly called yellow grease.
Waste from passive grease traps and gravity interceptors is referred to as brown grease. Brown grease is rotted food solids in combination with fats, oils, and grease. Brown grease is pumped out of the traps and interceptors by grease pumping trucks. The majority of brown grease ends up in landfill sites. As of 2012, new facilities and new technology are beginning to allow brown grease to be recycled.