Would adding a couple gallons of E85 to my #2 heating oil tank hurt?

My tank is down to the nasty sludge and some water at the bottom now. I heard ethanol both absorbs water and breaks down the thick sludge in fuel tanks. Maybe shut off my furnace before work tomorrow and add a few gallons? Supposed to get another 250 gallons of heating oil in the afternoon. Shouldn't that dilute the E85 enough not to be an explosive risk when I turn the furnace back on?