I believe him.....

Never underestimate the fun to be had growing up in fly-over country.....There was very little real trouble for a good kid to get into..
How did you light it? Magnesium strips? Sparklers? Torch?
Did you guys know that if a pile of small square hay bales containing 13,500 bales catches fire it will burn for 3 days and nights?
Did you know that when it is hotter than _____ in july and a hay barn you are filling catches fire you can run really really fast?
We built smaller hay barns after that. Fire was caused by hot muffler on another hay truck and busted hay bales not properly cleaned up. Help was summoned by CB radio

.. (no cellphones in 1970.) One two ton hay truck lost in fire and the frame was wilted and twisted.. not much left.
OP,
How did the spill turn out......? did you get it washed off?
Bill