Rinse off well with a hose, then place it in a rubbermaid style tub, then add water direct from the tap & allow to sit for 24-48 hrs. The chlorine/chloramine should wipe out most organisms that are on or in the wood. If you want to take it a step further, add a mega dose of kosher pickling salt, that should take care of anything that was lucky enough to survive the chlorine/chloramine. Then set out in the sun for a few days until the wood is bone dry. That will complete the sterilization process.
I've been using that process for years, never had any type of bacteria or pathogen survive it.
thanks for the tip, the wood is in a tub in my garage right now!