With a court deadline looming, the Carnegie Science Center and Don Barden are still battling over traffic and lighting issues related to his proposed North Shore casino.

Unless those matters are resolved by June 28, the science center will appeal the May 29 decision by the city planning commission to approve the casino master plan, Director Joanna Haas said yesterday. The appeal would go directly to the state Supreme Court.

The science center has put together a revised list of proposed mitigating measures it wants Mr. Barden and the city to formally agree to before the June 28 deadline. If the terms aren't accepted, the center will go forward with court action, officials said.

"We're not going to compromise on that. We've compromised as far as we can," said Ann Metzger, director of marketing and community affairs.

Neither Mr. Barden nor his company, PITG Gaming LLC, is in a position to accept the terms, spokesman Bob Oltmanns said.

He said the science center has added new conditions to what he described as a tentative agreement reached June 1. He said those conditions include curb cuts and a request to vacate Sproat Way near the science center that are city issues and out of Mr. Barden's control.

"Obviously we do not have an agreement. I thought we had a tentative agreement. Now there are new issues that they not only want us to consider but to acquiesce to, and if we don't acquiesce to everything, they say they're going to the Supreme Court," Mr. Oltmanns said.

He added, "Some of these conditions are brand new. We did not anticipate this. To me this is not how you negotiate in good faith."

But Ms. Haas denied that the science center had added terms. She said the curb cuts and the vacating of Sproat Way were discussed at the June 1 "working session." While there was "agreement on general principles" at the meeting, there was no tentative deal, she said.

One of the key sticking points continues to be school bus access to the science center. Plans for the casino, to be built between the center and the West End Bridge, would eliminate the existing access road.

The two sides have made considerable progress toward a deal on the construction of a new access road and improvements to a nearby lot to park buses for school students, who constitute about a third of the science center's business.

Still at issue is a traffic light at the casino entrance that both parties want but that requires city approval based on criteria established by the state Department of Transportation. City transportation planner Sidney Kaikai said yesterday he believes the signal will meet the criteria.

The science center wants Mr. Barden to commit, however, to backup plans if the light isn't approved; Mr. Oltmanns said Mr. Barden wants to wait to get a decision on the light before considering alternatives.

"We think it's essential and wise to have a Plan B," Ms. Haas said.

In addition, the science center still has concerns about the impact casino lighting will have on its observatory. It wants Mr. Barden to agree that light levels will not exceed 12 lux on non-game nights at PNC Park and Heinz Field. Currently light levels on non-game nights don't exceed 9 lux.

Mr. Oltmanns said the casino has been working with its consultants on that matter.

The science center, Ms. Haas said, has received "a lot of patting on the head" from city and PITG Gaming officials about its concerns but has yet to get any formal commitments. If it does not, it will have no choice but to go to court, she said.

"We have been forced into a corner where we have no option but to protect our interests," she said.

Litigation could further delay the construction of the casino, which has been held up by appeals filed by the two losing bidders for the Pittsburgh slots license challenging the award to Mr. Barden. The state Supreme Court has yet to rule on that matter.

Meanwhile, a city consultant yesterday reported considerable progress -- but no final agreement -- on the size and scope of a traffic study measuring the casino's impact on games and other events at Heinz Field and PNC Park.

Damon Rhodes, senior project engineer for Wilbur Smith Associates, said he hopes to be in position to move ahead with the study soon, perhaps by the end of the week.

"I think we took a big step forward in achieving that goal," he said.