(Corrects barrels-per-day figure in penultimate paragraph)
By Janet McGurty and Selam Gebrekidan
NEW YORK, March 1 (Reuters) - The Pennsylvania state senate will vote next Wednesday on a bill that would lift Pittsburgh's unique gasoline blend requirements, aimed at alleviating potential supply problems related to the shutdown of some of the state's refineries that make the fuel.
For many years, the former steel-making capital has used gasoline specially blended to burn cleanly and cut down on air pollution. However, the closure of two of the three Philadelphia-area refineries last year has left the city facing a supply shortage of the 7.8 Reid Vapor Pressure (RVP) fuel.
In January, the state senate, concerned about the effect of the refinery closures on Pittsburgh gasoline supply, introduced a bill -- Senate Bill 1386 -- to lift the special requirement.
"We have overwhelming support in the senate and over the state of Pennsylvania from consumers," said Mike Rader, executive director of the state senate's agricultural and rural affairs committee, adding the bill has found support from 40 out of the 50 state senators.
Buckeye Partners, which operates a major east-to-west gasoline and diesel pipeline, said shipments in its Chicago-to-Pittsburgh pipeline have increased following the shutdown of Northeast refineries.
A Buckeye representative declined to provide specific volumes. Midwest trade sources say the pipeline is running near full rates with gasoline shipments from Chicago.
The three Philadelphia refineries, which comprise about 50 percent of the northeastern U.S. refining capacity, fell victim to the high price of imported light, sweet crude, which is what they are configured to process into gasoline and diesel.
Sunoco Inc shut its 178,000-barrels-per-day refinery in Marcus Hook, Pennsylvania last year due to poor margins. It had failed to attract a buyer for the plant.
Supplies will be even tighter if Sunoco cannot find a buyer for its 335,000-bpd refinery in Philadelphia by July 1, at which point it says it will shutter the plant.
At the end of September 2011, ConocoPhillips ceased operating its 185,000-bpd refinery in Trainer and mothballed it while seeking a buyer. (Editing by Dale Hudson)