Beginning in June many U.S. agencies will be encouraged to set aside up to 20 per cent of their job vacancies exclusively for women and minority group members. The program could last five years, or until agencies satisfactorily increase the number of minorities in various pay and job levels.

The special emphasis hiring program has been cleared by the White House. It was designed by Jule Sugarman, vice chairman of the Civil Service Commission and a top Carter adviser on federal personnel matters. It is designed to increase the number of jobs now dominated for the most part by white men.Workers hired under the program would not have to take regular civil service tests or compete against regular job applicants for the positions. They would have two-year tryouts that would lead to permanent, career civil service jobs.

The special emphasis hiring concept was unanimously approved yesterday by the three CSC commissioners, the presidentially-appointed governing body of the federal merit system's watchdog agency.

Chairman Alan K. Campbell said that the special emphasis hiring program represents a broadening of the merit system.

Under the program, outlined here most recently on Nov. 30, federal agencies would be require to survey their racial, sex, ethnic and age makeup at various occupational levels. If it was determined that a group was under-represented based on availability in the national labor force, special emphasis would be given to hiring and training people for those jobs.

The special emphasis program includes Grades 1 ($6,219) to Grade 18 ($47,500). But most of the hiring, officials say, cold take place in Mid-levels at the 140 largest federal job categories, which have 2,000 or more workers in each category.

A task force of sub-Cabinet officials will be set up to work out details of the hiring plan, which has drawn praise from women's and civil rights groups, and cries of quota system from some professional associations and unions representing government workers.

The first step for the program, which is due to begin June 1, will be to determine what grades, agencies and jobs are lacking the proper numbers of women and minorities. In some cases figures will be drawn from the makeup of the national labor force, while for professional jobs the percentages of women and minorities enrolled in those disciplines will be the guide.

When it is determined by CSC or the agency that there has been an adverse impact on a group, that group is to be designated as a protected class. In the language of the CSC memo approved yesterday, it says that ". . . a finding that two or more protected classes are experiencing adverse impact in an occupation . . . " will trigger the special hiring authority for them.

CSC officials said they expect that most persons hired under the special emphasis program would come in under the designation Schedule A, a category used for lawyers and other groups of workers who are not given tests for government jobs.

Officials said that while 20 per cent of an agency's job vacancies could be set aside for the special emphasis program, they doubt that it will go that high except in extreme cases, and then only for a short period of time.

Agencies granted the authority to make the special emphasis hiring (and they will be encouraged by CSC to ask for it) can run programs for five years. At the end of two-years of successful work, the employee hired under the Schedule A authority may be converted to regular civil service status.

CSC officials say that individuals in a protected class will compete against each other or jobs and promotions, but they will not have to compete with persons coming in or up through regular civil service channels.

Asked what would happen if a regular civil service job applicant with top rating and someone from a protected class with top rating were considered for the same job, a CSC official said it would be "up to the hiring official" to decide who gets the job.

Although most emphasis in the special hiring program is given to women and black, the two major minority groups, CSC officials say that virtually any racial, ethnic or sex group cold benefit. In some jobs, white males are in the minority and they conceivably could benefit from special emphasis hiring programs for government librarian and teaching jobs.

Obviously, the thrust of the program is to increase the number of women, blacks, Oriental-Americans, Spanish-speaking persons and American Indians in government. Blacks now hold less than 5 per cent of the government's top-paying jobs while women have only about 2.8 per cent of the supergrade positions.

An official said the emphasis for the hiring would probably be at the middle grade levels, but that the program applies to major occupation groups and it was possible that some people from the protected class could be brought in at the top for the try out jobs. CSC has been considering trainee jobs for women at Grades 13 through 15 ($26,022 to $36,171), areas where men far outnumber women.