For Petersburg, a quiet rural southern town with a population of about 41,000, according to 1980 Census data, and an official unemployment rate of 8.5 percent, the Brown & Williamson plant has been economic mainstay for more than 50 years. At its peak, the plant employed 5,000 workers, but today the number is just over 1,000, and about 120 workers have been laid off since the closing was announced last year.

It is an older work force with a median age of 46, just under 50 percent of whom are black, and union leaders estimate that about 32 percent of the workers will choose to retire when the gates finally lock. It is also a very well-paid work force for the area with average wages of $13.83 an hour -- meaning that the majority of Brown & Williamson employes not only must search for scarce jobs, but also for ones that will pay less than they presently earn.

The plant itself is a multistory structure with equipment that no longer meets productivity needs in the industry. Still, the facilities are well maintained, well lighted and generally freshly painted with handsome pine floors in several buildings.

Although the decision to close the plant was made early in 1984, Brown & Williamson has been retrenching for almost a decade as its share of the shrinking cigarette market, buffeted by public disaffection and dire health warnings, has declined from 17.2 percent in 1975 to 11.3 percent last year. Tobacco revenue, however, has risen from $1.7 billion in 1980 to $2.3 billion in 1984. Brown & Williamson expanded briefly in the early 1970s when it built a new more modern plant in Macon, Ga., but by 1979 the company was closing its other major plant in Louisville, Ky., and beginning to cut back the work force in Petersburg. When Brown & Williamson shut the Louisville plant, it gave the workers more than three years notice and emphasized union-management consultations in setting up job-search programs such as the ones under way in Petersburg, albeit more limited in scope. --