Nauseating, Nasty, Foul, Offensive, Vomit...

The smell has been described as nauseating, nasty, foul, offensive, like vomit, like a "dead cow on your porch", "goes beyond stink", "it's not like anything else", rotting meat, something burnt, musky, a "dead, rotting carcus smell", a nuisance odor violation, and bad!

Q: Do you know what Renewable Environmental Resources LLC calls it?
A: Thermal Conversion Process Technology (TCP)

What do you think that it smells like? How would you describe it?