A boat that size you can dump at the Waste Management landfill off Little Neck Rd. for about 75-90 bucks, depending on weight.
They're closed on the weekends.
You have to remove the fuel tank and batteries. Another fun project.
Throw it back on craigslist for free and talk to everyone and their cousin from Nahunta, Baxley, Reidsville, Lyons, etc. None of them will have a truck much less a trailer to come get it, so they will try to convince you to deliver it to them for 20 dollars in gas money. On the way there you will lose a bearing/tire/spring/the boat will fall off the trailer, and you will wish you just paid the 90 bucks to dump it and chiseled the fuel tank out.