PALO ALTO -- A project that would trade a new public safety building for a pair of office towers in Palo Alto suffered a minor setback this week.

The city's Planning and Transportation Commission on Wednesday voted 4-2 to give the public more time to comment on the scope of an environmental impact report for the project.

The panel majority also said wanted more information, including city staff's plans to conduct public outreach.

"It just seems to me we need to put more creativity into what this environmental review is going to be about," said Chairman Eduardo Martinez, adding that he had no qualms about the project, just the process.

The public will have until July 31 to weigh in. The commission will also hold another scoping meeting that day. Without the commission's action, the period would have ended July 22.

Jay Paul Co. has offered to erect a 44,500-square-foot public safety building at 3045 Park Ave. in exchange for permission to construct a pair of four-story office towers totaling 311,000 square feet at 395 Page Mill Road. The existing public safety building, at 275 Forest Ave., is seismically vulnerable and has sat atop the city's infrastructure wish list for years.

However, Mark Michael, vice chairman of the commission, was troubled by the size of the project and its potential to wreak havoc on local roadways.

"As a resident, as a commissioner at the moment, I'm not thinking this is such a great project," he said. "The cumulative impact, which is another aspect of the (environmental impact report), is a huge concern, obviously, to the community and it's a huge concern to me."

Michael wondered whether the project should be shelved, not just momentarily delayed, until the city completes a concept plan for the surrounding California Avenue area.

"Maybe we should just wait," he said.

In a similar vein, Commissioner Alex Panelli said he wanted to better understand the value of the proposition before pressing forward.

"I am concerned about exchanging perpetual costs or problems for a one-time benefit. It's tempting and I understand the reasons for it," Panelli said, "but I want to make sure we have a really good understanding of what the trade-off is ongoing. Clearly, the applicant is getting a lifetime benefit for a one-time cost."

Other commissioners, however, were keen to push ahead and allow the environmental impact report to identify any shortcomings in the project.

"We're not approving the project (now)," said Greg Tanaka, who cast one of the dissenting votes. "All we're doing is studying the impacts of what could happen. And if it looks like there's something inadequate in the report, we can flag it, say, 'Hey it's not good. We have to do it again.' "

Land-use watchdog Bob Moss said the offer of a new public safety building was paltry considering the $20 million in annual rent the developer stands to collect on the new office space.

"In 2 ½ years, the gross rent would be more than they're paying for the police station. Then, for the next 30 or 40 years, all profit," he said.