By RUSTY DENNEN

Not far from the towering concrete-and-steel domes that enclose North Anna Power Station's two nuclear reactors, workers are preparing the way for a third unit.

Today, 10 years since Dominion Virginia Power filed its initial application for Unit 3 on Lake Anna near Mineral, the project is far from a sure thing, though the company insists it's still on track.

Opponents, meanwhile, argue that the ballooning cost of new reactors, coupled with ongoing delays in the approval process, low natural gas prices, and the fallout from the Fukushima disaster in Japan, make Unit 3 an unsure bet.

Eugene S. Grecheck, vice president of nuclear development for Dominion, says the plan has not changed: Nuclear energy continues to be a key component of the Richmond-based utility's long-term energy plan.

"We think it's very important to maintain a full diversity" of energy sources, Grecheck said Friday in a telephone interview.

In the words of Thomas F. Farrell II, Dominion's chairman, president and chief executive officer, Grecheck said "the question is not if, but rather, when" Unit 3 is built.

The recession and economic crunch has reduced demand for electricity, and natural gas prices have fallen dramatically with increased supply, making it a more attractive fuel, Grecheck concedes.

And Dominion plans to develop more natural gas capacity in the next few years.

"But in the long term, we are convinced that it is not in the company's interest, or the nation's interest, to be completely dependent on only one fuel," he said.

"Historically, the price of natural gas has been very volatile and subject to very big swings."

SOME PROGRESS MADE

Dominion's latest integrated resource plan--a 15-year guide for matching power generation, transmission and demand--projects that Unit 3, if the company proceeds, would be completed by 2024.

Dominion also owns the Surry Power Station on the James River, and two other nuclear plants--Millstone in Connecticut and Kewaunee in Wisconsin. Dominion announced in October that it is shutting down the Kewaunee plant this year after failing to find a buyer. The company failed in its bid to increase a nuclear presence in the Midwest.

Despite the hurdles, the industry has made some progress bringing online a new generation of more efficient and safer reactors.