I worked back the 70's age 18, as line "man" at an airport in N IL. The gas truck had two tanks one for 80/87 and one for 100/130. The airport also had two ten thousand ground tanks for avgas.
We as line " men" were supposed to top off the truck tanks each night from the ground tanks, this idiot that worked there on the night shift took the ground tank hoses one for each truck tank, put them the tank truck fill ports to fill the truck and started pumping fuel into the truck
it was winter and he tied off the fuel nozzles with electrical wire so he did not have to sit there in the cold outside, well he went home and forgot about the truck, two full ten thousand gallon ground tanks were emptied over night, most ended up on the ground, it was a sea of avgas when I got there in the morning, rather than call the fire department, the manager just let it seep into the ground and told me not to tell anyone, this was a Beech dealer and there were many airplanes sitting in the sea of fuel for days. I think gas was about $.50/ gallon back then. $10,000 of fuel gone, the idiot that did it, showed up right after I did in the morning after and wanted to know if I had shut off the pumps yet.