The fate of a plan to devalue seniority and give employes greater protection from layoffs based on their job performance may be decided at a brass-infested, closed-door meeting this afternoon on Capitol Hill.

At stake is the Office of Personnel Management proposal to revise rules that federal agencies follow when they RIF (fire) employes for economy reasons. Nearly 3,000 federal workers here have been RIFfed under the last-hired-first-fired rules since the Reagan administration took office.

OPM would reverse the RIF rules and require agencies to first RIF employes by groups--starting with those with the lowest job-performance ratings. Seniority would be a factor only within groups composed of people with the same performance ratings.

Under current rules, employes with the greatest job security during RIFs are disabled veterans, those with veterans' preference, and those with the most federal service.

Job performance is now given little weight during RIFs, except that workers with "outstanding" ratings are credited with an additional four years' seniority, and those with above-average ratings get an extra two years of seniority.

Under the proposed changes, a worker with long service but a low performance rating could be RIFfed before a very junior employe who had better performance ratings that put him in a grouping less likely to be touched by the RIF.

Republican members of Congress from the Washington area complained about the OPM-proposed changes. They took their case to the Office of Management and Budget, which acts as the White House's clearinghouse for legislative proposals and rules changes affecting federal workers..

Rep. Frank Wolf (R-Va.) buttonholed OMB Director David Stockman at the State of the Union ceremony on Jan. 25 and said he got Stockman's promise that nothing would happen on RIF changes until interested parties could get together for a face-to-face meeting. That will be today.

It will include OPM Director Donald Devine, a Stockman aide, Wolf (and perhaps other members of Congress), plus representatives of government-executive and manager groups that don't want seniority rules changed.

Women and minorities have long complained that RIF seniority rules hurt them most. They say women and minorities are hardest hit during RIFs because more-senior workers whose jobs are abolished can "bump" them into the unemployment lines.

OPM's proposed rules changes, which Devine says are consistent with merit principles, would also restrict bumping rights in the future RIFs.