While other politicians flog the federal bureaucracy for sloth and ineptitude, the Carter administration has singled out more than 250 superstars of the much-maligned career service for their good works. This year, for the first time, these outstanding bureaucrats are being rewarded not with plaques but with hard cash -- bonuses up to $20,000.

Harold R. Denton of the Nuclear Regulatory Commission became a familiar figure last year when his front-line role in the nuclear accident at the Three Mile Island put him on the networks. Denton's work helped him earn an extra $20,000.

Not many citizens have heard of Eckardt C. Beck of the Environmental Protection Agency. He was given primary credit for deciding to publicize the harzards of waste dump sites such as Love Canal in New York. He is another $20,000 bonus player.

Christopher C. Kraft Jr. of the National Aeronautics and Space Administration "made space travel the safest transportation in the world," President Carter noted at a Rose Garden awards ceremony for the top winners. With 35 years of service in the space agency, Chris Kraft became a household name in the 1960s, working out of Mission Control in Houston during the glory days of the Mercurcy, Gemini and Apollo missions.

But how many taxpayers know Claude J. Farinha, an Air Force manager in Sacramento, Calif? Farinha, according to his bosses, developed a management too called "integer of logistics" that saved $28 million in overhead costs in its first year.

Charles Swinburn of the Department of Transportation is unfamiliar to train passengers, but his work on the restructuring of Amtrak and other rail problems has saved taxpayers $100 million a year, according to DOT. And Swinburn also wins a $20,000 reward.

"When the president called my name, that really got me," said Farinha. "That was the high point . . . . My [immigrant] dad, with his faith in the American system, always said someday his son would be in the White House."

Like a number of other winners, though, the 55-year-old logistics specialist said one of the biggest thrills the award provided was "when I got to call my wife and tell her. You know, after all those years of long hours, many TDYs [temporary duty travel] that she's had to put up with, it's great."

"We all need to feel wanted and needed," said Beck of EPA. "The possibility of a reward might get us all working a little harder . . . . We don't do the peoples' business well enough. We must do better."

"You want to sound humble but . . . I'm glad to be recognized. The money helps too," said Anthony F. Ingrassia, of the Office of Personnel Management, who has eight kids to put through college. A top personnel executive, he won for his work in the maze of federal labor relations.

All these executives were among the 49 winners of the first $20,000 presidential rank awards for distinguished executives. There were also 206 winners of $10,000 meritorious executive awards.

But they are just the vanguard of a major new bonus program that is expected to total about $14 million and go to perhaps 1,400 of the nearly 7,000 senior federal executives in the first year.

The idea of cash bonuses as a reward for superior performance has been described by administration officials as a cornerstone of the president's fledgling effort to overhaul the civil service system and make government more efficient.

The program's supporters in the administration and Congress are painfully aware of how politically flammable this is at a time when the "bloated bureaucracy" is a prime target, and in a year of recession and elections. They emphasize that they are making great effort to keep reasonable limits on the bonuses and police them carefully.

Government agencies have always been big on handing out to employes baskets of plaques with no cash, or modest "incentive" bonuses with no well-defined pattern or controls.

These new awards are part of an attempt under the Civil Service Reform Act of 1978 to inject the sort of risk and competition found in the private sector into bureaucratic morasses, where the tradition has been as Carter has repeatedly charged, to reward longevity more than performance.

Officials emphasize also that top career executives have worked for some time under a pay ceiling (about $50,000), while lower-level workers have been receiving increases. This means that a number of top executives make no more than their subordinates several layers down. (A limit of $69,630 for combined pay and bonuses means that some winners received less than the full $20,000).

The awards are taxable.

In addition to the "carrot" of bonuses, there is a stick. The government's elite corps of senior executives agreed to give up their civil service job security, receive no regular pay raises and accept geographic transfers. Under a system of performance reviews being set up gradually throughout government, they can be dismissed after one or two years of less than satisfactory performance.

Federal personnel officials acknowledge, however, that it will be some time yet before the stick is really felt.

In the meantime, officials hope that by holding up a few standouts from the federal ranks as good examples, by demonstrating that good and bad workers do not all register as identical blips on the screen of bureaucratic accountability, by putting their money where their plaques are, they can upgrade morale and performance in a way the public will notice.

Earlier this year, a gun-shy Congress threatened to reverse itself and, just as the program was getting off the ground, prevent agencies from using the money for bonuses. A massive lobbying effort by the administration and bipartisan congressional supporters saved the program, though not without some cutbacks.

In the Rose Garden ceremony on Sept. 9 for the 47 men and two women who won the $20,000 awards, Carter said, "Some of you are the most important executives in America," and called them "the best of the best."

This group, selected for sustained achievement rather than any single deed, went through the most rigorous process of any of the new bonus programs.

They were nominated by their agencies and reviewed by an independent blue ribbon panel that included corporate executives, agency heads and specialists in public administration. Representatives of the U.S. Office of Personnel Management (OPM, formerly the Civil Service Commission) even sent investigators to double-check the claims made for them and interview their coworkers.

In addition, up to 20 percent of the nearly 7,000 senior executives are eligible for cash bonuses of up to 20 percent of their salary, though some bonuses will be much smaller, to be handed out by agencies on the basis of reviews by employe committees.

As certified by successive layers of examination, this first batch of superstars are the sort of sharp, hard-working, imaginative, problem-solving managers who are the exact opposite of the prevailing stereotype of a government worker.

Their ages range from 34 to 64, with a median age of 51.

Their jobs are comparable, officials say, to a corporate vice presidency. Many of them routinely control or influence the expenditure of millions or even billions of dollars.

Some of the selections have drawn fire.

"Anyone who reaches the level of a presidential rank award who isn't controversial is unusual," said Alan K. (Scotty) Campbell, director of OPM and the president's point man on the civil service overhaul.

Officials have received some letters of complaint from NASA employes, for instance, about the selection of Kraft on the grounds that he is too tough a manager, Campbell said, "I considered these letters high recommendations."

Political sensitivity was not a consideration in the selections, according to Campbell and others involved in the process.

"We were attached to people in areas where there were a lot of problems, who could cut through problems and make things happen," said Robert C. Holland, president of the nonprofit Committee for Economic Development and a member of the selection panel.

On the other hand, he added, "If the person had been following a line that created all sorts of fights and hassles down in their agencies, we regarded that as a 'management minus.' We are looking for performance -- stuff out at the far end that made society better or . . . cut costs."

"That bonus would have held [Beck's] secretary over for a whole year," grumbled an EPA employe who works with Beck. "I say that about half toungue-in-cheek. I can see how [the award] might set a good example for others . . . and he works very diligently. Puts in long days, and he's very creative. I don't dispute his accomplishments. I just wonder if it justifies a heavy cash award."

Howard W. Hjort of the Agriculture Department has drawn criticism from farmers because of the wording of his award citation, which credits him for "the shift in USDA policy from producer-oriented to consumer-oriented," among other things.

The subject took on so much political heat in fact that Rep. Charles E. Grassley (R.-Iowa) tried to make it an issue in his campaign to unseat Sen. John C. Culver (D.-Iowa).

"Anybody that knows me personally, I don't believe is critical," Hjort said. The economist left a more lucrative position with a private consulting firm at the urging of Secretary Bob Bergland, he said, adding, "Clearly . . . I did and can make more money on the outside. But there were some critical issues facing the nation and I suspect I am naive enough to believe that in this position I can have an impact."

Edward W. Scott Jr., of the Department of Transportation, was the target of critical publicity when he resigned to start his own business not long after receiving his $20,000. Scott and personnel officials agree that his plans to leave were known to his employers well before the prizes were handed out, and Scott said, the bonus was irrelevant to his decision.

But in discussing the criticisms, Scott expressed in stronger terms a theme touched on by a number of the winning executives in interviews.

"It isn't fun anymore, being a senior executive. It used to carry a certain status and standing in the community. But witness what happened when I got this award. Instead of saying, gee, Scott worked his butt off for the service, everybody took a random shot at me . . . It's a thankless, stinking job, and you get beat up all the time. Who needs that?"

Jack L. Stempler, 59, a lawyer who has the often uncomfortable job of representing the Defense Department on Capitol Hill, has been with the department for 32 years. He said that, at his stage in life, the $20,000 he won means less than the recognition.

"For whatever reason, a federal employe's standing around the country is not too good . . . People think you must be a jerk or something. The recognition helps wash that wound away that, I believe, will never get cured in the public mind."