Rig, an 18-wheelers carrying black powder to the quarries in Vermont broke down or had a minor accident or something on I-95 between Richmond and DC some years ago. Because of the cargo the cops closed down the Interstate (and caused HOURS of backup) and the firefighters called in the Army explosives experts.

Now, the powder was stored for transport in well-made wooden containers and kept in plastic bags inside the containers to keep out moisture. Instead of doing the obvious (water fog from hoses drenching the doors of the trailer while they were opened so the situation inside could be assessed) the military "advisors" brought in all sorts of remote handling equipment and stuff.

Then they drenched the trailer doors while someone opened them to assess the condition of the cargo (which was fine).

Remember the old adage "Keep your powder dry?"