I don't know the rules today, but at least in some parts of the US where explosives are used liberally no permits were required at all. You definitely didn't ne

I don't know the rules today, but at least in some parts of the US where explosives are used liberally no permits were required at all. You definitely didn't need to inform the government. This likely varies with locale. A considerable amount of explosive in the US is purchased by private individuals for all manner of purpose and use isn't on a formal schedule. Before 9/11, this was literally a cash and carry business in many States. You could back up a truck and fill it with explosives as long as you had a placard for your truck and a non-sparking liner. It simply isn't practical to track usage in many cases, even today.