Thousands of government workers who owe Uncle Sam at least $13 million in loans could find their paychecks 15 percent lighter in the future under legislation working its way through Congress.

The Senate and House are considering -- and expected to pass -- special debt collection measures aimed in part at federal employes who owe for either Veterans or education loans.

If the legislation is approved, federal salaries could be garnisheed by the government for up to 15 percent of net income until outstanding loans to the VA or the Department of Education were paid off.

Currently, federal paychecks cannot be garnisheed except by court order to satisfy court-ordered alimony and child support.

The new plan would still insulate government paychecks from most creditors.

In 1980, the government made a computer cross-check to see how many of its employes owed for those loans. It found that 83,000 employes owed over $50 million. A subsequent check showed that at least 30,000 government employes still owed those two agencies $15 million.

Both VA and the Department of Education will do another computer cross-check shortly, and that data will be used for garnishment purposes if Congress gives them the go-ahead.

The Senate bill, introduced by Sen. Charles Percy (R-Ill.), originally would have allowed the government to take up to 25 percent of the "disposable income" of federal workers for loan repayment purposes. It was modified to 15 percent to conform with a bill introduced by the late Rep. Adam Benjamin (D-Ind.).

The Senate plan would allow the government to attach employes' wages administratively, after a hearing. The House proposal would require the government to get a court order before garnishment could begin.

The House version affecting federal workers is part of the continuing resolution to keep federal agencies operating when the new fiscal year starts in October. In the Senate, the language is part of a major debt collection bill covering hundreds of thousands of people who owe the government money