The Agriculture Department yesterday notified nearly half its Federal Grain Inspection Service staff here that the unlucky ones will be out of a job next week, and the lucky ones, including some high-paid professionals, will turn into low-level clericals effective Oct. 1. The same thing is happening all over town as the RIFs (reductions in force) come home to roost.

The FGIS has about 250 people here. Seventy-seven of them have been told to clean out their offices. Another 45 have been advised they will be downgraded -- many from professional to clerical jobs.

Metro Washington's estimated 4,000 -- so far -- RIF victims will get up to one year of severance pay (depending on their time in government) and be eligible for unemployment benefits that largely are financed by Uncle Sam.

The downgraded people will, in most cases, be able to keep their current pay levels for two years. But they must start climbing the bureaucratic grade and promotion ladder all over again.

The RIFs are being done in the name of economy. They sound like a good idea to many people. But the impact is devastating to those on the receiving end of the RIFs, and to professionals who spent a lot of time (night school, unpaid overtime, extra effort) getting near the top, only to be handed a shovel or broom and told their duties will change next week when the new fiscal year begins.

White House sources said that the heaviest RIFs are yet to come. They say it is too early to tell how many jobs will be trimmed from the bureaucracy over the next two years -- but that published reports put- ting the target at 75,000 positions probably are accurate. If that is true, there are going to be some very unhappy fiscal new years in the bureacuracy for the next couple of years.