A company exists in Green Bay, Wisconsin that is in the animal fat business. Containers of restaurant fat along with truckloads of animal guts and hides from the livestock slaughtering business are brought in. The guts and hides are dumped on the ground and are scooped up with an endloader to be deposited in machinery that somehow removes that fat. I think the hides are sold for leather and the fat sold to be mixed in with animal feed as an energy source. If the wind is right the smell coming over the highway can be very bad. Just imagine what the site is like especially in the summer and what it is like working on and repairing the machinery! Cleaning up must be very interesting and dirty!