As long as you own the car, you could be held legally liable for anything that happens to or with it. I'd check out this article from e-how and follow their steps. The most important information would be to put something in writing with the junk dealer – I agree to buy/sell this car with VIN 12345667 and keep the bill of sale in case anything does happen.

Sell it as salvage – if someone decides to fix it up and register it, they will need to acquire a salvaged title anyways.
Get a bill of sale from the salvage yard specifically noting that the vehicle is sold as salvage.
In the state where I live, no reputable salvage yard will take in a vehicle less than 15 years old without a title. Older than 15 years – no problem.