The promise of a U.S. nuclear renaissance will start with thousands of pages in each regulatory application, and differences of opinion about the intricate process have already surfaced before the first has been filed.

“We’ve had pointed conversations on the level of detail” required, based on a 900-page guide the government updated in the last year, said Joe Colaccino, a reactor design expert at the Nuclear Regulatory Commission. “It’s the one (issue) we’re working on the hardest.”

The NRC also has issued or revised hundreds of guidance documents, and the utility industry has raised substantial concerns in areas including radiological monitoring of wastewater and vibration assessments for reactors during startup, said Adrian Heymer, senior director of new plant deployment at the Nuclear Energy Institute, a Washington-based trade group.

Industry wants a good rationale for a change instead of “someone thought it was a good idea,” said Heymer, who quickly added that there are “no showstoppers” and he expects the first new plant to begin operating in 2015.

A March report from the nonpartisan Congressional Research Service predicted the overall review and construction process would take at least 10 years and closer to 15 years for several reasons, including new procedures. Questions about environmental issues and safety evaluations also could cause delays.

Kenneth Hughey, senior manager of business development at Entergy Nuclear Inc., which is pursuing a license at its Grand Gulf plant in southwest Mississippi, expects the NRC to take the full 42 months to review the first few applications. However, he said the timeline should shorten if industry builds standardized plants.

“They do need to get more efficient in their review process,” said Bryan Dolan, vice president of nuclear plant development at Duke Energy. The government reviews should take no more than 24 months, he said.

NRC Chairman Dale Klein has said the reviews should quicken once the first license for a certain reactor design is approved. In June, the commission approved some internal task force recommendations designed to conserve resources and trim the reviews by between six months and 15 months.

However, one company already has delayed its nuclear plans. Progress Energy in May told the NRC that if it opts to build a new reactor in Wake County, N.C., the plant would be online in 2018 or beyond, two years past where its initial forecasts.

Still, the NRC is training hundreds of workers to process the 19 applications expected through 2009.

Bill Borchardt, director of the NRC’s Office of New Reactors, said the agency is establishing processes to apply its regulatory decisions repeatedly so subsequent reviews will be shorter.

Each application will include about 2,500 separate tasks that require requests for additional information. About 100 government employees will work on each application and every reviewer will be managing tasks on multiple projects.

“We don’t have anybody with any dead time,” Borchardt said. The Office of New Reactors started with about 85 people late last year and is expected to grow to 430 by the end of 2007.

“This is a long haul activity, this isn’t something we can just lock the doors and work 24/7 for a week,” he said.