I don't know the exact amount but it's ALOT, and the ship is rusting away. When the fuel bunkers finally collapse there is a fear there will be an environmental disaster!
There was a rumor that among the Navy's solution to the failing wreck was to build a cement sarcophagus around and over the ship.
Because of local and stateside politics, the Navy's plans have been frozen at the “idea” stage.
I do recall that the Arizona had a full bunker on December 7th. I believe this was about 2,100,000 gallons of 420 cSt heavy oil.