PITTSBURGH - Drivers in parts of western Pennsylvania see gas prices rise each summer due to a regulatory requirement aimed at reducing emissions, but that could change starting next year.

Officials decided in 1999 to require gas stations in a seven-county region around Pittsburgh to switch to a "summer blend" of gasoline from May to mid-September.

The state House approved a bill Monday to seek an end to the regulations, and the state Senate approved House amendments Wednesday. Any change would need the approval of the federal Environmental Protection Agency.

State Sen. Elder Vogel Jr., R-Beaver, said the requirement has meant a 10- to 15-cent increase per gallon in gas prices. He calls it a "hidden tax" on the region and says it isn't needed because "We have no steel mills anymore."