That's quit possible
we once got a tanker delivery and i was on my own, so i shut the pumps off and went to dip the tanks on the tanker after this i told the driver where to drop the petrol IE premium tank's Super and regular he started off OK but the tanks in the ground held 6000 gals premium 15000gals reg and 2000 super the driver got it wrong and tried to put 4000 in the 2000 gal tank
i caught him just in time but we lost about 30 gals through the breather pipes at the side of the garage where a little old man was standing with a bucket catching the vented fuel
we had to call the fire service to clean up but at least one old man got about 5 gallons free
but no stamps