I was in SoCal dealing with these issues since 1981, between CARB and the local air boards it got tougher as time went on. BACT determinations didn't always seem to have technical backing behind them, someone would make a claim and that would get pushed down to the users, and a lot of times the end results caused performance and reliability problems. Several of the "new" ideas would decrease one constituent, usually NOx, but cause drastic increases in particulate and CO. CARB finally got SWRI more involved and at least testing and evaluation got done to address some of the issues, but usually political pressure pushed most of the regulations down the users throats.
Biofuels in marine environments had other problems as well, mainly biological growth and oxidation, needing to add additional fuel additives and increased fuel delivery and storage systems maintenance adds significant costs long term for the operators.
Makes me glad I don't deal much with it anymore.
Tug, my contact at SWRI has retired and moved on, I haven't been able to find much additional info as I hoped I would.
MikeL.