Civil servants concerned about a higher retirement age wouldn't have to start worrying until the next century under a novel proposal worked up by Republican staffers of the House Post Office-Civil Service Committee.

The very long-range cost-cutting plan will be one of many schemes Senate-House conferees tackle next month when they begin work on a retirement plan for the 300,000 feds hired since 1984. That new plan is supposed to be approved by May. It won't directly affect benefits or the retirement age of most people hired before 1984.

The committee's minority staff is proposing that any new retirement plan gradually raise the retirement age for covered federal employes. A similar system, already approved, will gradually raise the age at which persons covered by Social Security can retire with full benefits.

Currently, feds with 30 years' service can retire at age 55 without penalty. Persons under Social Security must wait until age 65 to get full benefits. That age will rise to 66 in the year 2009 and to 67 by 2027.

The GOP staff plan would raise the federal retirement age to 56 by 2002 and to 57 by 2022. One Democratic staffer said the proposal "sounds weird . . . but weird things crop up in a conference." Gradually raising the federal retirement age, GOP staffers claim, would reduce the retirement system's price tag.

It is only one option Congress will consider when it works up a new retirement system for federal workers hired since 1984. The Senate has approved two different plans and the House committee a single plan for those post-1983 feds. Each would base pension benefits on Social Security, a modified civil service annuity and an optional tax-deferred savings plan.

The conferees will consider a number of proposals in their quest to work out a compromise that government employe unions, Congress and the president will approve.