The administration will do this by having the EPA issue an emergency waiver for the summer sale of E15. Typically, E15 cannot be sold in most of the country between June 1 and Sept. 15 because of air pollution rules. The White House has argued that the use of E15 can shave 10 cents off each gallon of gasoline. E15 is currently sold in 30 states at more than 2,300 gas stations, the Energy Department has said, but that is just a fraction of the more than 150,000 gas stations in the United States.