The question really depends on whether you truly have the ability to actually walk 20+ miles per day and have the experience of walking over the terrain specified with a 20-30lb uncomfortable load. i.e. the rubber maid container can be converted into a basic back pack using the vehicle seat belt strapping.

The ability to navigate would be crucial. This scenario isn't really a question about kit (what you would take and leave behind) but about experience in suffering a little without giving up on the unplanned trek.

The scenario sounds pretty tough for even the folks from the US Army Mountain division. For others it would be a fun outing.

http://toc.hipcast.com/deluge/167d028d-85f3-c98d-73b5-ef1ca08588a0.mp3