Mitsubishi has a procedure for the MiEV pack which involves placing it in a wooden crate lined with a heavy plastic film, then filling this "tub" with water, and waiting 72 hours.
Basically you could put it on a sheet of plastic film on top of a pallet, then carefully build some side walls without puncturing the film, to make a tub.
i don't know if this will help with disposal, but it should remove any concerns over transporting a hot pack that has voltage.
edit: no salt in the water, just tap water. Salt causes the reaction to be too aggressive and release excessive hydrogen gas. Water makes it react, salt water reacts too fast.