Bay Area Air Quality Management District or BAQMD has jurisdiction and also collects the yearly fee for burning through a 100 gallons of diesel annually.
One of the old engineers asked my why I let it bug me... he said all the new regs is what keeps us working...
Told him I just don't like to see waste... no matter who is footing the bill.
Sad.... doubly so, as a lot of N. America follows Ca policy some time later....
True enough, it's not just the EPA that likes these make-work programs.....
Rgds, D.