HARRISBURG — Tens of thousands of state employees might have to take two unpaid furlough days per month under a cost-savings proposal that an adviser to Gov. Ed Rendell outlined to union officials Thursday.

Secretary of Administration Naomi Wyatt told the union representatives the involuntary furloughs would last through June 2010 and save state government about $89 million, said Pennsylvania Social Services Union President Kathy Jellison, who was at the meeting.

"I can't imagine the chaos it would cause to the system," Jellison said following a meeting in Harrisburg with Wyatt, a labor lawyer for the administration, and with David Fillman, head of Council 13 of the American Federation of State, County and Municipal Employees.

The unions Jellison and Fillman represent cover the majority of the 78,000 full-time state workers.

Rendell last month unveiled a $29 billion budget for 2009-10 that included a wide array of spending reductions. He proposed closing state-run schools, eliminating nearly 600 positions from the Department of Labor and Industry and cutting funding for libraries, public television and anti-drug education.

Rendell spokesman Chuck Ardo said earlier this month that some of the governor's proposed cuts and furloughs are unavoidable because the state faces a $2.3 billion projected shortfall. But he said Thursday that ongoing negotiations might avert the previously threatened furloughs.

"We believe that progress can still be made to avoid the worst-case scenario," Ardo said, adding there was no firm date for when the furloughs might begin.

Ardo said Rendell had legal authority to impose furloughs unilaterally, but Jellison disagreed.

"We have an obligation to our members, and we're going to hold to that obligation, and the obligation is the contract," Jellison said.

Fillman said the unions were looking for other ways to save $89 million, an amount equal to what supervisory employees are losing between the start of the current calendar year and July 2010 by working without wage increases as the state grapples with its budgetary shortfall.

"I do not have the ability to undermine or open up the contract for concessions," Fillman said. "What I am getting from my members is they are not in the mindset of doing that. So we are looking at relief everywhere."

It wasn't immediately disclosed which employees would be subject to the furloughs. During the budget stalemate of July 2007, many state workers stayed on the job while Rendell furloughed for one day 24,000 state workers not deemed critical to health and safety. He closed state parks, state-run museums and driver's license offices.

Fillman said he told the administration it was a bad idea to have some people working while others were sent home.

"We told them they don't want to go there," Fillman said. "It's going to create a lot of animosity in the work force. There would be Jane at work and Bob will not be at work."