Robert Borger, a 15-year veteran coach driver with Sun Tran, boards passengers at Tohono Tadai Transit Center. A strike is likely to happen Monday if Sun Tran and union drivers and mechanics can't agree on a new contract. JAMES GREGG / ARIZONA DAILY STAR

The more than 60,000 daily Sun Tran bus riders could have to make alternative plans on Monday, if the company that operates the service for the city and union drivers and mechanics can't agree on a new contract this weekend.

Teamsters Local 104 and the management of Sun Tran have a final meeting Saturday, the day the union's three-year contract expires. Union members will vote on the contract on Sunday, with a strike possible Monday if the contract is rejected.

Neither side will talk about what the issues stalling an agreement are, saying they won't negotiate through the media.

Katrina Heineking, Sun Tran's general manager, said Sun Tran will try to offer some limited service if there's a strike but said there's obviously no way it can manage full service with the union on strike.

One major issue that appears to be driving the looming impasse is the city's on again, off again consideration of spinning the Sun Tran and Sun Van transportation systems off to the Regional Transportation Authority.

Union representatives and Sun Tran workers have been lobbying hard for the transfer, in the belief it will buffer them from the city budget crunch and ongoing staff cuts other city services are facing.

For months, numerous Sun Tran workers have attended City Council meetings with placards urging a takeover by the RTA, which oversees the transit plan approved by voters in 2006 and is funded by a half-cent sales tax.

Andy Marshall, executive officer of Teamsters Local 104, has spoken in front of the council several times, saying time was running out on the union negotiations and the city should approve the transfer to the RTA.

He said the deal would benefit both sides, because the RTA has more money to operate the bus system, and the transfer would give city taxpayers relief because they wouldn't have to subsidize the operation any longer.

In late May, Marshall said one council member had suggested a 3.5 percent wage cut for the union, which would match what city workers got because of the furlough days they were forced to take. He said a better idea is to transfer the bus system to the RTA.

On Friday, Marshall said he believed the city was about $7 million short in funding for its 2010-2011 budget. That is a major concern because route cuts could lead to 100 employees being laid off.

"The city has to come up with the money to pay for transit," Marshall said. "You can't run it if you don't have the money. The RTA has money. … It all comes down to money."

"The union has made it perfectly clear they're interested in the transition (to the RTA) because of the perceived shortfall at the city," Heineking, the Sun Tran manager, confirmed.

RTA Executive Director Gary Hayes has pushed for the transfer, despite the fact that an Arizona Daily Star calculation shows it could cause a $72 million shortfall in the RTA's budget over 15 years. Hayes said that hole will be filled with operating efficiencies and federal grants.

Several nonprofit organizations and advocates for the poor are planning a protest Monday against the transfer because they fear it will lead to higher bus rates.

Some bus riders said the strike would be a big inconvenience to them and their families.

Frank Williams, a deputy clerk with the Pima County Superior Court, said he takes the bus into downtown from East Golf Links Road and South Harrison Road every day and will have a hard time without bus service. He said he will go to the bus stop Monday morning and hope to find a carpool.

"We are a one-car family," said Williams, noting bus service doesn't go near the location where his wife works. "It's not going to be convenient."

Sharon Thomas, who works at the Indian Village Trading Post downtown, said her husband could drive her to work for a few days but she couldn't afford the gas money for much longer than that.

"It's gonna hurt even more the people who are on economy fare," because they don't have money for other transportation, Thomas said. "The poor in the city aren't going to be able to do anything."

For the latest information on possible service changes, call 792-9222 (TDD: 628-1565) or check www.suntran.com

"The city has to come up with the money to pay for transit. You can't run it if you don't have the money. The RTA has money ... It all comes down to money."

Andy Marshall, executive officer of Teamsters Local 104

Contact reporter Rob O'Dell at 573-4346 or rodell@azstarnet.com