Labor Secretary Raymond J. Donovan has selected Ellen M. Shong to head the department's Office of Federal Contract Compliance Programs (OFCCP), the government's most potent affirmative action enforcement arm, according to informed sources.

Shong, 33, has worked since 1973 on the management side in civil rights matters and is a member of the U.S. Chamber of Commerce Equal Employment Opportunity Task Force. She was an affirmative action administrator for AMAX, Inc., at its Climax (Colo.) Mine, starting in 1976, and later at the Golden, Colo., Climax Molybdenum Division.

The compliance office she will direct is responsible for monitoring and enforcing job bias regulations among employers who hold federal government contracts. Included are about 350,000 organizations with a work force of nearly 40 million.

Shong is unknown to civil rights groups, according to several of their representatives, because of her experience has been on the management side of equal employment issues.

What little is known about her "is certainly a reflection that the commitment of the department to strong civil rights enforcement is going to change drastically," said Nancy Kreiter, an official of the Chicago-based Women Employed. "It's not encouraging for us. . . . She is the candidate of the business community."

Labor Department officials declined comment on the appointment, noting that no announcement has yet been made.

A native of Lansing, Mich., Shong graduated from Michigan State University in 1969 and received a law degree from the University of Arizona College of Law in 1975.