Phase separation occurs when water enters an underground storage tank. Some of the water will be suspended in
the fuel, binding to the ethanol. The rest of the water will fall to the bottom of the tank, pulling ethanol with it. Over
time, this ethanol-water mixture will continue to pull more ethanol from the fuel. It
is important to note that you will never have pure water sitting at the bottom of a tank of ethanol-blended gasoline.