The clock is ticking for the Portland Diamond Project to start paying real money to reserve a marine cargo terminal for its billion-dollar baseball park — or give up on building at the site.

By the end of the month, the pro baseball boosters could have to start paying the Port of Portland hundreds of thousands of dollars each year for the exclusive negotiating rights to the Northwest Portland terminal where they hope to build a 32,000-seat stadium. The bill for the first three months will come to $375,000.

But the Diamond Project has only just begun to sort out thorny issues around transportation and zoning that could keep the field just a dream.

And while the group has enjoyed an air of credibility by having a site identified, it has entertained alternatives.

For its part, the Diamond Project says the terminal remains its preferred site and declined to discuss other possibilities.

“We’re forging ahead,” spokesman John McIsaac said Thursday. “Business as usual.”

McIsaac suggested the group could request an extension but hasn’t determined whether it would be necessary.

Officials from the Port of Portland said discussions continue apace, and there’s been no talk of an extension.

“We’re still having regular conversations,” said port spokeswoman Susie Rantz. “They’re still interested, as far as we know.”

But a Portland city official said the site is looking increasingly unlikely.

Marshall Runkel, chief of staff for City Commissioner Chloe Eudaly, who oversees the city’s Transportation Bureau, said there’s been little progress in addressing the challenge of getting thousands of fans to and from the games.

The site, northwest of the Fremont Bridge, has infrequent transit service and lies more than a mile from the nearest MAX line. It sits on a road that’s not built for a heavy influx of traffic.

“It still looks very difficult or impossible from a transportation standpoint to make Terminal 2 work,” Runkel said.

The terminal also sits on designated industrial land that, if rezoned, would put pressure on city planners to designate industrial land elsewhere. That would attract opposition from environmental groups.

After the due diligence period, the Diamond Project will have to pay for the exclusive right to the site and abandon efforts to acquire property for a stadium elsewhere. After the initial payment of $375,000, the Diamond Project would have to pay $125,000 per quarter for the next three quarters, then $187,000 per quarter for the next year.

It’s not clear what alternative sites the Diamond Project might have its eye on.

Before landing on the marine terminal, the group had previously considered three known alternatives: the Portland Public Schools headquarters near the Rose Quarter, a former metal foundry in Northwest Portland and the South Waterfront holdings of the Zidell family.

The school district said it’s had no further conversations with the Diamond Project since it withdrew an $80 million bid to buy the building. The Diamond Project cited conflicts with an alternative development plan for the district, the Albina Vision, which aims to reunite the historically black neighborhood torn apart by Portland’s urban renewal efforts.

Same with the group of investors who bought and are in the process of demolishing the metal foundry, which was built on the historical Vaughn Street Stadium, where the Portland Beavers once played.

The Zidell family, through spokesman Kevin Glenn, demurred: “They don’t have anything to say at the moment.”

The Diamond Project has pushed out a steady beat of news on its proposal as it drums up support at home and tries to win over officials at Major League Baseball.

The group — led by former Nike executive Craig Cheek, former Trail Blazers broadcaster Mike Barrett, Seattle Seahawks quarterback Russell Wilson and Grammy Award-winning singer Ciara, Wilson’s wife — released conceptual renderings of the stadium it’s proposed at Terminal 2, as well as a list of a dozen local investors.

But there are plenty of questions still unanswered, including who would pay for the venture. The group has shown Mayor Ted Wheeler pledges from big-money investors, but it hasn’t released their names.

The stadium itself would cost more than $1 billion. Acquiring a team, whether through league expansion or relocation, could cost a similar amount.

-- Elliot Njus

enjus@oregonian.com; 503-294-5034; @enjus

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