Allegheny County Chief Executive Dan Onorato yesterday encouraged the Port Authority's union to allow its full membership to vote on a fact-finder's recommendations for a new contract and possibly stave off a looming systemwide shutdown.

Port Authority's board last week unanimously accepted the proposal, while the executive board of Amalgamated Transit Union Local 85 -- led by its president and business agent, Patrick McMahon -- rejected it.

Mr. Onorato, who favored the recommendations, continued to warn that the transit agency is verging on bankruptcy and might have to cease operating by year's end because of staggering future liabilities for retirees.

Recommendations by neutral fact-finder Jane Rigler would whittle those pending costs by saving nearly $90 million over a three-year contract and much more in the long term.

"I would ask for Pat to please reconsider this and to let his rank and file vote on it," said Mr. Onorato, who, along with Port Authority Chief Executive Officer Steve Bland, met with Pittsburgh Post-Gazette editors yesterday. "I think the majority would see this as a fair deal to fix the authority."

Mr. McMahon rejected putting the issue before his membership, explaining that he did not have to. He described the proposal as "concessionary" and said he would not cave in to fear-mongering about a possible shutdown.

"First of all, the union does understand the financial issues, the economy today," Mr. McMahon said. "But I'm going to tell you right now: If Dan Onorato thinks that the union's going to come to the table and negotiate out of fear, well, he's got something else coming."

Mr. McMahon said there was no reason to put the fact-finder's recommendations before his members, whom he said support the executive board's decision.

"If the union executive board decides that it's not worth consideration for acceptance, then it's done. Period," he said.

Mr. McMahon expressed confusion over Mr. Onorato's suggestion that the recommendations be put to a vote. He noted that under the law, if either side rejected the proposal, it would be off the table.

Mr. Onorato acknowledged as much.

"This is no longer a starting point. It's ripped up, and if Pat rejected this thinking he's going to start from here and get a better deal, no," Mr. Onorato said.

He and Mr. Bland said, however, they would be willing to accept a late union decision in favor of the recommendations.

What they are not interested in is having the union accept some portions of the proposal, which calls for annual 3 percent wage increases, higher health insurance payments and a later retirement age, but not others.

"If we were to get a call this week that said, 'Hey, you know what, we've gotten some feedback,' we wouldn't kill it right now," Mr. Bland said. "We'll continue to try to bargain in good faith. We haven't seen any movement in their opening position."

The pair said Ms. Rigler's proposals were not perfect for either side, but praised them for spreading the pain and tackling the thorny issue of so-called "legacy" costs for retirees.

"There were some significant changes that we haven't seen in any negotiations probably in 20 years," Mr. Onorato said.

Critics of the union's contracts complain that health care and pension provisions have been overly generous for retirees, creating an enormous liability that needs to be reduced.

The union believes it has made enough concessions, and Mr. McMahon claims that cost-cutting suggestions it has put forward have been met by resistance from the Port Authority.

"We've put things on the table in front of the fact-finder, and they simply say, 'No.' That's all they've done so far. It's not enough. It's take it or leave it. And that's their negotiating style," Mr. McMahon complained.

Mr. Onorato holds a powerful carrot: roughly $27 million earmarked for the Port Authority and collected from controversial county taxes on vehicle rentals and alcoholic drinks. That money would allow the transit agency to leverage about $185 million in state funds. And that would permit the Port Authority to continue operating. But he pledged late last year to withhold the money unless the Port Authority reduces its legacy costs.

Mr. Onorato said he expended considerable political goodwill in getting behind the unpopular taxes, and he also said riders had done their part by absorbing fare increases and service cuts. Now, he said, it's the union's turn.

Mr. Onorato was adamant that he would not release the funds unless the union addresses the legacy problems, even if it meant that Port Authority would fail under his tenure. He said a shutdown would be the union's fault.

Releasing county funds as a stop-gap measure might help the agency for the next few years but would not ease the core fiscal crisis, he said.

"If the union does not come to the table, the doors will be shut because there's nothing else I can do. There's no more taxes. There's no more cutting that can be done."

Both sides said they were willing to continue negotiating. Mr. McMahon said he was drafting a letter to Mr. Bland that says just that.