The Pennsylvania Turnpike is preparing to revive its application to impose tolls on Interstate 80 as the clock ticks toward a new statewide transportation funding crisis.

Meanwhile, opponents today will unveil a study that concludes that I-80 tolls are unjustified and could lead to an increase in crashes.

Turnpike spokesman Carl DeFebo said the agency soon will submit supplemental information to the Federal Highway Administration in support of the I-80 application.

The administration notified the state 13 months ago that its bid did not meet legal requirements for a national pilot program under which three interstate highways would be tolled.

One deficiency was that the state did not provide justification for the amounts the turnpike commission would pay the Pennsylvania Department of Transportation to lease the highway and convert it to a toll road.

Mr. DeFebo said the turnpike is preparing an analysis of the highway's market value that could be submitted to the FHWA by the end of the month. While he said "it would be nice to get a definitive answer," Mr. DeFebo acknowledged that the federal government might raise additional questions that delay approval.

I-80 tolls were a linchpin of Act 44, enacted by the Pennsylvania Legislature in 2007 to fund highways and public transit.

If I-80 is not tolled and no other funding is substituted, Act 44 funding of highways and transit would drop from $900 million annually to $450 million starting in July.

PennDOT statewide would get $300 million less in highway and bridge funding and transit agencies would take a $150 million hit. That would sharply curtail road and bridge repairs and trigger new financial emergencies at transit agencies like the Port Authority and Philadelphia's SEPTA.

Critics of the toll proposal today will release a study by a Grove City College associate professor of economics, Tracy C. Miller.

It concludes that drivers currently using I-80 are "already paying more than enough" in fuel taxes to cover the maintenance costs for the 311-mile cross-state highway, Dr. Miller said.

The report will assert that traffic diverted onto secondary roads such as U.S. Route 422 to avoid tolls would lead to more crashes, he said. Also, the tolls could place a financial burden on businesses employing 75,000 workers, leading to lower profits, wage reductions or layoffs, he said.

Dr. Miller did the study at the request of anti-tolling groups but considers it impartial. He said a better option would be a small increase, 1 or 2 cents, in the state's gasoline tax.

Based on turnpike estimates, it would take a much bigger increase to offset the I-80 toll revenue, estimated at $350 million to $400 million in the first year. The gas tax generates about $65 million per year.

Two foes of I-80 tolling, U.S. Reps. Glenn Thompson, R-Howard, Centre County, and Kathy Dahlkemper, D-Erie, will attend separate events in Grove City and Lamar, Clinton County, to roll out the study.

Mr. Thompson has introduced legislation to prohibit the tolling of interstate highways. Ms. Dahlkemper earlier this year said tolls on I-80 would drive commerce and tourism away from Pennsylvania.

The turnpike commission, in an effort to curb opposition, has designed a tolling system that would spare most local motorists. It would set up nine toll collection points across the state but charge passenger cars only if they pass at least two of them.

It estimates that 70 percent of the cars using I-80 would be spared the tolls.

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