The loan guarantee was first announced in February, amid fanfare from nuclear proponents. Southern Co. had 90 days to accept the deal and was granted an additional 30 days to decide. The 1,100-megawatt reactors would be built alongside two existing reactors at the Vogtle nuclear facility, which was built in the 1980s. The new units are expected to be completed in 2017.

The loan guarantee is not yet written in stone, however. Southern Co. said final approval and release of the money "are subject to receipt of the Combined Operating License from the U.S. Nuclear Regulatory Commission (NRC), completion of final agreements, the receipt of any other required regulatory approvals and satisfaction of other conditions."

Nuclear Design Yet to Gain Approval

The AP1000 nuclear design by Westinghouse Electric Company has been selected for the Vogtle plant's expansion. The model has faced a barrage of criticism. Though currently under review, it has yet to be certified by the NRC, overseer of the nation's 104 nuclear plants, and is not operating anywhere in the world.

Environmental groups have said the reactor design has structural faults that could make it less safe than America's current nuclear fleet. In particular, they allege the proposed "shield building" structure may not be robust enough to protect the reactor from tornadoes, earthquakes and other forces. A report commissioned by SACE also said the "containment building" — the reactor's so-called "last line of defense" — would be vulnerable to radiation leaks in the event of an accident.

The design is on its 18th revision. Last October, NRC put the brakes on the review process in response to shield building concerns. In a memo to Westinghouse obtained by SolveClimate and released on June 21, the agency established a new schedule of approval that targets a final decision on the design in September 2011.

Westinghouse has defended the safety of the reactor, saying it is "the safest and most economical nuclear power plant available in the worldwide commercial marketplace."

Southern Co. has said it expects to get its final operating license by the end of 2011, though opponents are skeptical of that date among potential new hurdles and many unknowns.

"It's a long, cumbersome process," Barczak said.

There are three other reactor projects at the top of the DOE short list to get loan guarantees — in South Carolina, Maryland and South Texas. Among those projects, the South Carolina project by utility South Carolina Electric and Gas is the only other site that would use the AP1000 design. Currently, 14 AP1000s are under regulatory review at seven sites across the American Southeast.

See also:

Georgia Judge Rules Against 2 Controversial Nuclear Reactors

Coalition: Design for New Nuclear Reactor Less Safe Than America's Current Fleet

Obama's $8 Billion Nuclear Boost Dogged by Safety Concerns

Where Is Nuclear Power Really Heading?

Nuclear Power’s Cost Competitiveness Remains a Critical Question

Nuclear Energy – White Knight or Dangerous Fantasy?