Everyone has known for years that ethanol blends are basically evil. It has cost boat owners millions of dollars in tank maintenance and repair. It's been well know that a blend of ethanol over 10% will cause damage to vehicles.
BUT....
The corn growers association lobby is very powerful and they have the clout to get the epa to approve this crap.
Corn ethanol is a net loss product. More energy is used, and more pollution is made, in its production than is saved by its use in vehicles. It has less energy in it than gasoline does, so it reduces your mileage.
Fun fact about what kind of damage ethanol can do:
Ethanol will pull the binding ingredients out of fiberglass. Those binding ingredients will pass through a fuel filter and when burnt by the engine, they leave a residue that builds up and hardens in the cylinders and on the valves. So that means complete engine rebuild. Then, after a while, when all the binders have leached from the fiberglass, the tanks basically disintegrate. Costing thousands to clean up and repair.