All the draws missed, which usually means villains call light. Check/fold river.
Also, I'd rather check/call (or check raise) the turn than bet it. Villain isn't folding any part of his range on that card. While we have a boatload of equity, we're still semi-bluffing a non-folder.
Even though you have a really big draw, you need to realize that you're still semi-bluffing. And even though its a semi-bluff, its still a bluff. And a 2NL, bluffs don't usually do much other than deplete your chip stack. Only time I consider betting this river is if its an ace.