When the EPA was created in the early 1970’s standards for gasoline were established that maximized the performance of Internal combustion engines, which at the time had carburetors. Since the advent of fuel injectors and on-board computer systems that regulate the air/fuel mixtures; the fuel standards have never been updated, to account for the fact RVP standards are changed every few months throughout the year.
Lets use EPA oversight/exemption authority to set the Reid Vapor Pressure (RVP) standard for gasoline at 9lb RVP year round, with a 1lb waiver for ethanol blends. The EPA has this authority already and it would enshrine some common sense into a 50-year old law.
The advantage to one RVP standard would help the daily and seasonal operation of refineries, pipelines and retail stations. Excess butane could be sold. Gasoline terminals and pipeline would no longer need to draw down inventories prior to the Spring gasoline season. Lots of operational and price efficiencies would be achieved, with more stable pricing. The fuel transportation industry would benefit and so would the consumer.