Seven years ago, Congress and the Reagan administration agreed that offering cash to federal workers who report waste, fraud or other abuses in government programs would be a good idea.

It may still be a good idea, but, according to a recent study by the General Accounting Office, it's not one being widely used.

The GAO surveyed the program, known as the Inspector General Cash Award Program for Cost Savings Disclosures, at the six largest government agencies: Defense, Treasury, Health and Human Services, Agriculture, Interior and the Veterans Administration.

The GAO's investigators found that five of the six agencies had not granted a single cash award between March 1985 and March 1987 and had made no attempt to publicize the program.

The Defense Department -- the agency that awarded prizes -- distributed 25 awards totaling $30,000 in that period. Defense officials told the GAO, Congress' investigative unit, that the employee tips resulted in net savings of about $43 million.

The cash award law, passed in 1981, states that "the inspector general . . . may pay a cash award to any employee of such agency whose disclosure of fraud, waste or mismanagement to the inspector general of the agency . . . has resulted in cost savings for the agency."

The law does not make a cash payment mandatory and approves of the awards only in cases where tangible cash savings or recoveries occur. The federal government has other cash incentive programs, such as the Defense Productivity Awards, that reward inventiveness and hard work. But the waste and fraud award was supposed to be a major tool against inefficiency, and at the time the administration heralded its support as evidence of its commitment to eliminating sloppy expenditures.

Most agencies, in responses to GAO criticism submitted for the report, complained that the current tight-fisted budget climate makes it difficult to find money in agency budgets for awarding those who report abuses.

"If inspectors general are to provide the money," wrote James R. Richards, the Interior Department's inspector general, "most of them would be unable to do so since there are no funds provided for awards and their appropriations are primarily made up of salary, benefits and travel money."

John F.W. Rogers, assistant Treasury secretary for management, said the agency found cash awards "are not necessary to encourage Treasury employees to report alleged instances of fraud, waste and mismanagement."

The 1981 law is permanent for the military but must be renewed by Congress for civilian workers by Sept. 30. The GAO report urges Congress to consider strengthening the law's language or earmarking specific funds so that agencies reward deserving workers.

It also recommends that Congress consider extending the incentive program to government contractors and to cases where a dollar figure for the resulting savings is impossible to set.