After a 14-month review, the General Services Administration told 122 of its employes yesterday that they will be transferred or dismissed by Dec. 1 because a private contractor, ARA Services, has been hired to run the Franconia Stores Depot, the largest government supply center.

GSA regional administrator William F. Madison said he told 78 permanent employes at a mass meeting at the center they would be guaranteed other area jobs with GSA or they could join ARA Services under a preferential hiring plan written into the contract.

GSA will "try" to find jobs for the 44 temporary employes, Madison said, but some could end up being dismissed.

GSA estimates that by turning the management of the depot over to ARA, the government could save more than $5 million over three years. The warehouse, on Loisdale Road just south of Springfield Mall, stockpiles and distributes supplies for all civilian offices in the area.

"It's bad news for government employes; it does not portend well for the future," complained Howard Daniel, vice president of Local 1800 of the National Federation of Federal Employees, one of two unions that represents employes at Franconia. "I've gotten the impression that if the contracting-out of Franconia goes well--and it has--they'll contract out more facilities."

Amy Swartz, a GSA official, said the agency had solicited private sector offers to do mechanical maintenance at two of its field offices in the area, one at the Veterans Administration and the other at the Health and Human Services Department. Madison said the 82 federal workers affected "are likely to be transferred" to other GSA jobs if the decision is made to contract-out the work.

But Daniel said that it was unlikely that GSA would be able to continue to find jobs for GSA employes when work is contracted-out. There are 28 other groups of industrial and commercial operations run by GSA in the Washington area that are being studied and could be contracted-out to the private sector.