If the tank is that empty, couldn't an owner grab a couple 5 gallon gas cans, fill them, put them in a warm garage, and then fill the tank with the warmed gas? Shouldn't that melt the frozen water faster or with less work anyway?
Wouldn't the gas be above freezing as it comes from the pump due to the underground storage tanks? I figure the underground tank deal benefits the stations with water in the tanks as the ground keeps the water liquid!