A statewide grand jury sitting in Pittsburgh has heard from a number of former turnpike employees, including its former second-in-command, as part of a probe into allegations of corruption, according to several sources close to the probe.

Pennsylvania Attorney General Tom Corbett is trying to determine whether so-called "pay-to-play" arrangements with contractors and political interference exist at the turnpike.

Among those questioned by the grand jury is the turnpike's former second-in-command Kevin Longenbach, who was forced out of his position two years ago.

The first indication of an investigation came in September, when the Morning Call of Allentown quoted a commission source saying he had been questioned regarding turnpike contracts. More information came out after an online publication specializing in the toll road industry reported that FBI agents had raided the Pennsylvania Turnpike Commission headquarters near Harrisburg last week. The commission and the FBI both strenuously denied the reports by Toll Roads News, an internet site based in Frederick, Md., but then details began to emerge about the grand jury in Pittsburgh.

The initial report of a raid was softened yesterday to reflect a visit by an FBI agent. Toll Roads News also quoted a construction supervisor for a turnpike widening project outside Philadelphia saying he had been questioned by the FBI about cost overruns and the delivery of defective concrete products.

The Pittsburgh grand jury, being overseen by Mr. Corbett, is looking into possible links between political donations and turnpike contracts.

Investigators earlier this year began looking into allegations in a civil lawsuit by former turnpike Labor Relations Manager Donald Kovac.

In federal court pleadings, Mr. Kovac alleged that he was terminated by the commission last year after he refused to reinstate a politically connected toll booth worker who had been accused of physically assaulting a motorist during an altercation.

The complaint says that at the turnpike "the unwritten rule was that PTC union employees who had favored political connections would be afforded favorable treatment at the second step of the grievance procedure -- favorable treatment that was not available to other employees."

The complaint also declares that when members of Teamster Local 250, which represents turnpike employees in the western half of the state, ceased donating money to the Philadelphia Democratic Committee, a turnpike manager named Melvin Shelton, "instructed plaintiff to deny all grievances brought on behalf of employees represented by Local 250."

Mr. Kovac's complaint also says he told turnpike Executive Director Joseph Brimmeier that he believed Mr. Shelton, in fact, did little work for the commission "but rather, worked to further the interests of Congressman [Robert] Brady, the Philadelphia Democratic Committee and Teamsters Local No. 77."

The commission is contesting those allegations and Mr. Kovac's civil case remains pending.

Neither he nor Mr. Longenbach could be reached yesterday. Three sources connected to the investigation said Mr. Kovac was questioned briefly and was asked about political machinations inside the turnpike.

Turnpike spokesman Carl DeFebo said the commission would be issuing a detailed response about possible investigations into the turnpike operations.

He indicated that allegations of cost overruns and contract irregularities in a paving project outside Philadelphia had prompted the commission to request the FBI to look into the matter.

The probe comes six months after Gov. Ed Rendell fired Mitchell Rubin as chairman of the turnpike commission. Mr. Rubin, whose wife was convicted in a separate case involving former state Sen. Vincent Fumo, D-Philadelphia, received a "target letter" from FBI agents in Philadelphia informing him he faced possible criminal charges.

Federal investigators are looking into allegations that Mr. Rubin held a $150,000 no-work state contract with the state through his private business, BNR Preferred Revenues.

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