I suspect most flammables and explosives would have been kept in a storage shed behind the General Store.
At MGM we had "The Sign Shop". They made nearly all the signage for the studio and any of the productions who asked for their services and could provide a charge number.
Worked the same way in "The Metal Shops". If a set designer, set decorator, UPM needed something made and had a charge number, we made it. I worked on effects and set pieces for Brainstorm, War Games, 2010, Red Dawn, Ice Pirates, Last Starfighter, Dallas, CHiPs, Fame, Max Headroom, Dracula, Hook, Turbulence, Air Force One, and a few others.
Had an uncle who was in charge of the MGM Property Dept. back in the '50s. He ended up working as a "set decorator" on well over a hundred movies and TV shows. I've seen his name in the credits of "Get Smart", "The Courtship of Eddie's Father", at least one John Wayne movie, a Tom Cruise movie and at least one Gene Wilder/Richard Pryor movie.
The motion picture and television industry is huge, but still a small world. About a year ago, I was sitting in the radiology dept's waiting room at the motion picture hospital, waiting my turn to get my broken foot xrayed. Got to talking to a retired transportation driver who knew Rick.