A grease trap and a grease interceptor is a device that is used to trap grease and solid waste before entering the water waste disposal system.
A grease trap is a small grease disposal device usually located under the sink above the ground. Sizes are usually will vary from 10 gallons up to 500 gallons. Due to the small size the grease trap should be serviced more often to prevent overflows and clogging.
A grease interceptor is located under the ground and it will hold more than the grease trap. Sizes of grease interceptors are usually within 500 gallons and up. Service increments for grease interceptors are longer than a grease trap because of its waste capacity.