Hopefully not to bad. I think it is going to be one of those sit and wait to see what comes. From the sound of it alot of tarred up oil on the bottom waiting for warm water to get it moving again. Just cross your fingers and hope.
I personally think that it'll affect the delaware estuary for decades. The tanker was carrying a "heavy" petrochemical that was going to be refined and used for asphalting roadways and such. The Delaware, even in the channel is a relatively shallow waterway (40ft?) As water temps increase, portions of the tar/asphalt I think will liberate and rise to the surface and cause problems for years. I'm not a chemist or anything, but this is just my feeling. On top of this, there are still thousands of gallons unaccounted for. I hope I'm wrong.