How can I clean the dirt, grime, mildew, oil off of a wooden pallet?

Gato asked:


I placed a pallet in my garage to store some household items on and I have my garage cooled with a duct from my central air. I’m scared that any dirt from the pallet might get re-circulated through the central air vents in the house so I want to clean this pallet real good. Any thoughts or ideas?

Air Duct Cleaning Atlanta