More than 50 years after the nuclear age began here with the development of the bomb, the Atomic City is striving to become more than a company town tied to a nuclear weapons lab.

While Los Alamos National Laboratory still pumps in the lifeblood of high-paying jobs, the days of federal subsidies are over for this mountaintop community built by the government in secret and closed to the public until 1957.After years of paying Los Alamos an annual $2.6 million, or about 13 percent of the county budget, the Energy Department last year sent a final lump sum of $17.6 million. It also plans to turn over to the county the water system, airport and fire stations and has given it $5 million to create a repair and upkeep fund.

"It's time to stand on our own," said Denise Smith, a county councilor who owns two restaurants and a shopping center. "We want it to be without pain."

In order to become self-sufficient, Los Alamos needs to attract business to diversify its economy and broaden its tax base. It has three grocery stores, a department store and shops - like Atomic City Auto Parts. Still, the city relies heavily on the lab for jobs.

Diversification won't be easy. The federal government not only gave Los Alamos life but built much of its infrastructure, from streets to houses to schools. About 40 percent of the county work force works at the lab, which has 10,000 employees.

And land is an issue.

With tax-exempt federal land making up some 90 percent of the county, there is little available for sorely needed housing or commercial enterprise. The Energy Department, which owns nearly half of county land, pulled some of the 8,000 acres initially being discussed off the table, saying the lab might need it in the future. Other acreage was deemed unsuitable because of the mountainous terrain.

"It's about change, about cultural change. For a lot of people it has been hard to distinguish Los Alamos the community from Los Alamos the lab," said Paul Dickman of DOE's Albuquerque office.

The laboratory was established in 1943 as the headquarters for the Manhattan Project, the U.S. program to beat the Germans in creating the atomic bomb.

Scientist J. Robert Oppenheimer selected Los Alamos for its remote and inaccessible location atop Pajarito Plateau at 7,355 feet and shrouded by the Jemez Mountains.

Today, jobs at the lab provide the foundation that makes Los Alamos one of the wealthiest counties in the nation with a median household income of more than $54,000 and the best-educated with 54 percent of all adults holding a bachelor's degree or higher.

Los Alamos, 34 miles northwest of Santa Fe, is focusing on attracting high-tech companies that would complement the lab. While the lab's primary role is still developing nuclear weapons, it also does computer, biomedical and environmental research.

County officials also want 1,500 more houses in the next 10 years to attract businesses and their employees. Today, Los Alamos is home to 18,600 people.

"We have the setting, we have the schools," said Rich Kraemer, a California transplant who has lived here since 1982. "We need to able to provide the housing for those who want to move in."

The county's plan also will look at ways to bring in retail businesses.

"What town of almost 20,000 doesn't have a car dealer, doesn't have an appliance dealer, doesn't have a major furniture dealer?" asked Lawry Mann, chairman of the County Council.