Twenty-five years after a power company last got permission to build a nuclear reactor in this country, Dominion has signaled its interest in doubling the size of its North Anna power plant, 80 miles south of Washington, with two new reactors.

The company has filed an initial application -- called an "early site permit" -- to build two more reactors at its plant on Lake Anna. It is a preliminary step in a complex process that, if followed, would take more than a decade and cost millions of dollars. And it has attracted attention from anti-nuclear activists and some local residents.

Federal energy officials predict that electricity needs will rise nearly 40 percent by 2020, and Dominion, which provides 17 percent of Virginia's electricity, says expanding the North Anna facility would help meet the demands of a ballooning Washington area population. North Anna powers 450,000 homes. Doubling its size would feed an additional 400,000, the company says.

Currently, Virginia gets 35 percent of its power from nuclear sources, and Maryland gets 28 percent, compared with the national average of 24 percent. As America's appetite for electricity expands, the Bush administration is looking to the nuclear industry to help meet the demand by adding the equivalent of 50 new reactors to the country's 103 by 2020.

But Dominion's intentions, however preliminary, have spawned opposition.

Anti-nuclear activists have descended on the Lake Anna area since the company filed a preliminary permit application to the Nuclear Regulatory Commission last fall, visiting fairs, diners and convenience stores to speak out against the expansion. A group based in Charlottesville has sprung up, calling itself the People's Alliance for Clean Energy, and a conference on the expansion at the Lake Anna plant was scheduled for this weekend at the University of Virginia.

In the recreation-minded community that has grown around the lake, there has been reaction of a different sort.

Bill Borduin, a retiree from New Jersey who chairs a local committee on the possible expansion, said residents worry that two more reactors, which would need to be cooled by Lake Anna water, would mean a drop in water levels, leaving boats beached and docks high and dry. Some are concerned that the water used to cool the reactors would be so warm when it reenters the lake that it would raise lake temperature levels too high for comfortable swimming.

"Also, I bet it would create an enormous amount of humidity," Borduin said.

The local civic association also has questioned how the water temperature and levels might affect fish.

Such leisure-oriented concerns should not be surprising. Most of the people who live around Lake Anna, which straddles Spotsylvania, Orange and Louisa counties, moved there to be near the 13,000-acre lake, created in 1971 to cool water for the nuclear power plant, located in Louisa County.

In addition to $10 million in annual tax revenue for the county, the plant provides 900 jobs, making Dominion the largest employer in Louisa County.

Fitzgerald A. Barnes, chairman of the Louisa County Board of Supervisors, said he has not gotten a single phone call about Dominion's application.

"Not nay or yea," he said. "People here worry about working and trying to raise their families."

Anti-nuclear activists bemoan the lack of local passion about North Anna.

Abhaya Thiele, a volunteer with the People's Alliance, said it was "disheartening" to see how few people from the Louisa area have come to public hearings. She said officials are not pressing Dominion enough on its proposal and nuclear safety in general. "Democracy has been thwarted," she said.

Richard Zuercher, Dominion's spokesman on nuclear issues, emphasized that the steps the company has taken are very preliminary.

"We haven't committed to build anything at North Anna," Zuercher said. "From our standpoint, we're a forward-thinking company, and our customers expect us to be looking out for their energy needs in the future."

The process of adding nuclear power capacity is long and costly. Since 1979, when the industry was thrust into chaos after an accident at Three Mile Island melted the core of a Pennsylvania reactor, the procedure for obtaining permits for new facilities has been overhauled. Officials say the entire power industry is watching closely as Dominion and two other companies -- in Illinois and Mississippi -- start down the regulatory road.

If Dominion decides to pursue the project, it would take 10 years to complete it at the speediest pace: six years minimum to get the construction permits and operating license and four years to build, Zuercher said.

New technologies have sent the cost of new reactors skyward. Separate from the millions invested in the permitting process, reactors cost about $1.5 billion apiece. In the 1970s, the two now at North Anna cost $1.3 billion together.

The federal government is offering financial help to Dominion as it navigates the long permitting process. The Energy Department is investing $5 million to help Dominion through this first step, the quest for a preliminary permit that banks the government's approval for 20 years. The company also has asked for $250 million in federal money to help get the required construction and operating permits. Action on that request probably will not come until after the November election, federal and Dominion officials predict.

Dominion's characterization of its permit application as "preliminary" is no comfort for opponents of nuclear power.

"Our biggest concern is this is going forward and no one has considered if it's a good or bad thing," said Brendan Hoffman, with the national group Public Citizen, which has raised concerns about nuclear accidents and questions about how nuclear waste would be handled.

Spotsylvania, Va., resident Aviv Goldsmith, 45, who developed small power plants before he retired, is advising Virginia opponents. Among his concerns is the proximity to Washington of what could be a relatively large concentration of reactors at a single plant, especially at a time when concern about terrorism is high.

"Why would we want more nuclear material so close to the heart of the government of this country?" he asked.

As part of the permitting process, several groups petitioned the Nuclear Regulatory Commission, complaining about a number of issues regarding nuclear waste disposal, the amount of water available for cooling at Lake Anna and the environmental impact of the new reactors on rockfish and other aquatic life in Lake Anna and the watershed of the North Anna River. The commission agreed that environmental issues need a closer look, but it dismissed seven of the nine issues raised by the petition.

The two reactors at the North Anna power plant could become four, based on permit requests filed by the owners.People's Alliance worker Abhaya Thiele, left, shares information with Anna Point Marina store manager Brenda Hydro.