(1) An owner or operator of a small tank barge covered by an oil spill prevention plan on file with the office in compliance with chapter 317-21 WAC shall possess financial responsibility in the amount determined under subsection (2) of this section. If the owner's or operator's oil spill prevention plan is disapproved by the office or voluntarily withdrawn, the owner or operator shall possess financial responsibility in the amount of at least five hundred million dollars ($500,000,000).

(2) Financial responsibility for a small tank barge is the greater of two million dollars ($2,000,000) or:

(a) For tank barges certified to carry persistent oil, $3000 per barrel of the barge's total capacity, or if assigned a load line under 46 C.F.R. Parts 42 or 44, per barrel of allowed capacity; or

(b) For tank barges certified to carry nonpersistent oil, $1,500 per barrel of the barge's total capacity, or if assigned a load line under 46 C.F.R. Parts 42 or 44, per barrel of allowed capacity.