100LL use in 582

The ethanol is added in the truck at the distribution point, and mixes on the way to the gas station.  Find the distributor -- there is a good chance that they will be happy to sell you ethanol-free gas for your boat at their main location, or be able to tell you where to get your boat gas.

The guy I used to share a hangar with bought a little trailer and put two 55-gallon drums on it, with a pump, hose and grounding wire.  This is under the threshold for HAZMAT transportation regulations.  At the time, the nearest station with pure gas was about 50 miles away (now there's one just 20 miles from here), but the total cost of fuel and the trip was still well below using 100LL.

FYI, 100LL has THREE TIMES as much lead as 80/87 Avgas, and autogas is made to a HIGHER standard than 100LL!

Autogas is made to a higher standard than 100LL? Say what?

Good but older article on avgas vs auto gas.  https://www.avweb.com/ownership/avgas-vs-autogas/ Bottom line is that 100LL is the same no matter where you get it (federally regulated), and auto gas is not federally regulated and can and does differ in formulations from state to state. So which "higher" standard is being used. I don't buy that argument at all.

As for cost. Today, premium auto gas with ethanol is $3.10/gal in my town, 40 miles away I can get premium  ethanol free for $3.20/gal, and 100LL at my home base airport is $3.80/gal. So I'd save at most $0.70/gal.  If I fly 100 hours a year at 5 gal/hr, that's 500 gallons. $0.70 * 500 = $350 per year, but I would have to build a trailer to transport it, license and register the trailer ($118/year in my state), haul it , store it, etc.  To me that is just too much hassle for the potential money saved. If that is significant enough for someone else, then that is up to them, but I don't feel for an average flyer that there is enough monetary savings to make it worthwhile.

If it was readily  available nearby I would definitely run ethanol free autogas simply because it is recommended by Rotax. I would even run 10% ethanol blend autogas if it were not for the incompatability with my fuel tanks. The fact fuel tank compatible autogas is not readily available is the problem. Sounds like the decalin is a good alternative for those in my situation.

100LL is federally regulated is why I don't believe that it is a lower standard. There's extremely precise limits for contaiminants and AKI and freeze point and more that is just not the same with auto gas where every place you get it might be different with only a few federal guarantees.