The head of the trade association that promotes ethanol says gasoline price hikes in the Midwest are the oil industry’s direct attack on ethanol. He calls it the most “scurrilous campaign” he’s ever seen.Renewable Fuels Association president Eric Vaughn says big oil’s trying to discredit ethanol so Californians will push to end federal rules which call for switching to ethanol, as the fuel additive M-T-B-E is contaminating water on the west coast. That will create a bigger market for ethanol.Vaughn says the oil industry doesn’t want to give up that market-share to the corn-based fuel additive. Oil refiners say it’s too expensive to mix ethanol with conventional gasoline, and that’s why prices have skyrocketed. Vaughn says the investigation of the recent gas prices hikes doesn’t have to take forever. He says the oil companies can move quickly if they chose to.Vaughn spoke yesterday at the “Farms, Food and the Future” conference in Des Moines. M-T-B-E is already banned in 11 states, including Iowa and 27 other states are considering bans on the oil-based fuel additive, which reduces smog emissions from cars.