You’ve been warned. Gas prices are about to get pumped up, eventually climbing to the year’s highest levels as refineries across the nation are preparing for maintenance season and the seasonal switch to cleaner burning gasoline, a tradition despised by many. The hikes are due to summer’s more expensive blend of gasoline, required by the Environmental Production Agency (EPA) and the Clean Air Act, as well as refinery maintenance work lasting several months that causes gasoline production to drop, creating a pinch at the pump.