CHICAGO (CBS) — The Chicago Public Schools and their teachers are back to square one in their efforts to agree to a contract and avert a strike, but schools chief executive officer Jean-Claude Brizard remains optimistic.

On Wednesday, the Chicago School Board and the Chicago Teachers’ Union both unanimously rejected a fact-finding report by arbitrator Edwin Benn with suggestions on how to end the contract stalemate. The report advised that teachers should get a pay raise of nearly 15 percent next year, and about 35 percent over four years.

Read The Full Report Here

After the report was shot down, Chicago Teachers Union President Karen Lewis accused school officials of going out of their way to see that they would prevail.

“In all honesty, they did everything they could to tilt these negotiations, and to tilt the law, and to tilt everything in their favor,” Lewis said Wednesday. “And we see that they already have everything in their favor. We would like to see that kind of stuff every step of the way to be a real level playing field.”

Brizard said CPS had no such agenda.

“No one was looking to tilt anything to any particular direction,” Brizard said, speaking on the CBS 2 Morning News Thursday. “Our goal is to have a fair contract for teachers, to be sure that we have the conditions we need for success.”

Brizard added that even after the fact-finding report did not resolve all the issues as CPS had hoped, he remains confident that the issues will be settled and a contract agreement will be reached.

“Perhaps I’m an optimist, but I know Karen Lewis. I know she’s interested in having a contract. Just about every teacher I talked to really wants to get back to work in August and September,” Brizard said. “Of course, now we have a time crunch. We’ve got to make it happen. The one thing that the public needs to know is that we have not stopped talking. We have not stopped negotiating. It has been ongoing throughout the fact-finding process. The monetary issues are big ones, but one we hope to come to a resolution on within the next several days.”

Brizard also disputed the characterization relations between CPS and the teachers’ union as “toxic.”

“You know, contract negotiations often are contentious. What makes this much more difficult is the economic condition of the district. What is being asked, or perhaps being offered by the arbitrator, and what we can actually pay, is miles apart,” Brizard said. “But we have to come to a resolution. The relationship is not toxic. We’ve been working and talking to each other. You saw the report – we’re going to have a cordial, respectful relationship. We need our teachers. We need the union. We’re going to keep working together to make sure we come to a resolution.”

School is set to open in less than a month for a third of the city’s public schools. The schools n the “Track E” calendar begin classes on Aug. 13, while other schools start on Sept. 4.

Benn said both sides share in the blame for the contract stalemate. He said CPS should not expect teachers to work a school day that is 20 percent longer without an adequate raise, but noted the teachers got a great deal in their 2007 contract, just before the economy went in the tank, so they can’t expect similarly generous deal this time around.

Benn said the board has to pay teachers adequately for a longer day – and should have known that going into contract talks.

But Benn also noted times have changed since the last teachers’ contract in 2007.

“For its part, the Union is coming off an extremely lucrative contract for the employees for the period 2007-2012 — even with the 4% wage increase withheld for 2011-2012 — as its terms were negotiated prior to the devastation caused by the Great Recession,” Benn wrote. “The Union cannot ignore the fact that its membership immensely benefited from the terms of that lucrative contract and cannot expect the same type of benefits to continue when the economic conditions are far worse now than when the 2007-2012 agreement was negotiated.”

Benn’s report suggested a 2.25 percent cost-of-living adjustment and a 12.6 percent pay hike for teachers next year, for an overall raise of 14.85 percent. Over the next four years, the report recommended an average 35 percent raise for teachers.

But CPS has budgeted only for a 2 percent raise next school year, and plans to raise its property tax levy to the legal limit, as well as drain its entire reserve fund to plug a $665 million budget hole next year. School officials estimate, in the first year alone, Benn’s recommended raises would cost the district $330 million.

Union vice president Jesse Sharkey also said the union wanted Benn to accept proposals to provide job security for hundreds of veteran teachers who were laid off last year.

Whatever stumbling blocks remain in front of them, the two sides must now hash out a compromise without an arbitrator if they are to get a deal done before the school year starts.

Both sides will sit down again on Thursday to resume traditional contract talks, without a mediator, and talks are expected to progress at a rapid pace.

LISTEN: WBBM Newsradio’s Bob Roberts reports