Government is certainly the dominant business in the Washington area economy, even if the private sector each year chips away at that dominance and increases its employment share of the total labor force.

But the backbone of both government and the growing business base is a legion of clerical workers - secretaries, bookkeepers, stenographers, clerks, typists and cashiers. These people are to Washington what the autoworkers are to Detroit and the garment workers to New York.

So fast is this employment sector growing that by 1985, the clerical work force will number nearly half a million, or about one-fourth of all jobs in the metropolitan area projected for that period.

This is the startling conclusion of a new forecast for the area by D.C.'s Department of Labor and the study would seem to indicate that local government and educational planners face a difficult task of developing the necessary training of young people for clerical skills.Priorities may have to be shifted.

Otherwise, the metropolitan area in the next decade could be suffering from the sort of employment crisis now faced by the District: A surplus to young people out of work, with few skills to match available jobs.

To be sure, there is more than one feasible approach to finding work for unemployed persons. One possibility is to attract to Washington the sort of light industry and manufacturing base which needs less skilled workers. But that sort of industry has never been located here in significant strength. Prevailing high wage scales, which reflect the government's own pay levels, rule out industrial development without significant new tax breaks for the businesses to be attracted.

It may be cheaper and more practical to consider launching a new, broad educational effort aimed at meeting the jobs market that already exists.

Typing and clerical skills are taught in many area schools but without the sort of comprehensive educational program and associated facilities devoted to academic and college-oriented courses. Moreover, basic knowledge about the economic system among young people is abysmal.

Vocational high schools in D.C. have stepped up efforts to teach clerical skills but area business leaders say privately that quality has not improved, as measured by recent graduates. Fairfax County transports students to skills centers for concentrated business education programs and business people say graduates there are better trained.

In any event, development of several business high schools in the city and suburbs may be warranted. Courses and extra-curricular activities at these schools could be oriented toward business skills, a return to commercial high schools of an earlier era before future college enrollment became the only glamorous high school educational program.

To whet the appetite of the area's educational and government establishment, they might want to consider the following statistics from the new study, forecasting the four highest demand occupations here through 1985 with annual average openings based on economic growth:(TABLE) Occupations(COLUMN)Openings Secretaries, except legal(COLUMN) and medical(COLUMN)11,500 Typists(COLUMN) 3,950 Cashiers(COLUMN) 1,730 Bookkeepers(COLUMN) 1,720(END TABLE)

Also high on the list of new job openings each year are receptionists (1,110), real estate agents (920), file clerks (760), statistical clerks (720), legal secretaries (650), and retail counter clerks (560), all of which could be filled by Washington area young people trained for the work.

But these figures understate the situation for job categories in which there is a rapid turnover - such as clerical - as people are withdrawn from the labor force due to deaths, disability, relocation and other reasons. When these job changes are added, the total number of annual new clerical employment opportunities here exceeds 35,000 - far ahead of the next-highest category, professional and technical workers, at 21,000.

According to the D.C. government report, clerical workers became the largest occupational category in metropolitan Washington several years ago. "It serves as the backbone for word processing, correspondence, and other record keeping necessary for the direct administration of the federal government, and the activity of the service industry, a major portion of which supports the administration of the federal government," the report states.

In the next year, all clerical workers are expected to number 412,700 out of a total work force here of 1.59 million. By 1985, the clerical work force is expected to total 476,000 and the overall employment base, 1.8 million. The clerical sector is the fastest-growing among all occupations, and is expected to increase 26.5 percent in the 1974-1985 period.

Unless area residents are qualified for these jobs, they will be taken by newcomers to the area, as people inevitably are attracted to markets where jobs they can handle are located. That will swell the population base and make area retailers happy.

But, at the same time, government statistics show that area unemployment exceeded 85,000 in July. And the D.C. government states that 184,500 residents of the city need adequate employment - counting people out of work and people whose skills are underutilized, economically disadvantaged, recipients of public assistance or people with income below poverty levels.

The overwhelming majority (97 percent) of economically disadvantaged persons are nonwhite and 75 percent are under 30 years old, which led the government agency to make the following assessment:

"Overall, planners and administrators will find themselves continually instituting programs and developing jobs aimed at helping mostly young, black, poorly educated and unemployed persons toward maximizing employment opportunities and enhancing self suffiency."

The challenge faced by government, given the number of area young people involved, could hardly be greater.

But the numbers will continue to swell, given current employment trends, if nothing is done to begin the process of quality business and clerical training in the school system, so that high school graduates will have the skills that match the sectors of employment where growth is taking place.