With a twinkle in her eye and a shovel in her hand, one excited resident of a group home for the mentally retarded in Alexandria helped kick off construction of a two-story apartment building for retarded adults near the Del Ray section of town.

This week, during a special ground-breaking ceremony at 417 E. Bellefonte Ave., Sheltered Homes of Alexandria began construction of an apartment building designed to provide shelter and supervision for at least 12 mildly and moderately retarded adults.

"It's the step before the final step to independent living," said Paul Wexler, executive director of Sheltered Homes of Alexandria.

This nonprofit organization, which began in 1974, established a group home for men in 1975. The group then opened a workshop for the mentally retarded before building a second group home for women in 1976, said Wexler.

Construction of the current project, which will begin within the next two weeks, according to the contractor, is scheduled for completion in November.

The supervised apartment living experience is part of a national trend to de-institutionalize mental patients and place them in the least restrictive environment possible. The project is beginning at a time when mental health service planners say there is a dramatic need to find alternative living arrangements for retarded citizens who could better "seek out their potential if they were not institutional," said Wexler.

According to Wexler, the project began after Sheltered Homes of Alexandria received $154,000 from the Federal Rent Subsidy Program for the Elderly and Handicapped.

Wexler said the money for this pilot project cames as the result of a joint effort by the Virginia Housing Development Authority and the Virginia Department Authority and the Virginia Department of Mental Health and Retardation.

"We will provide furnishings for those residents who cannot afford them and all of the residents will only have to provide a quarter of their incomes toward the rent of the apartment," added Wexler.

Candidates for the new apartment will be selected by a special committee which will evaluate the abilities of the mentally retarded citizens.

Although the costruction of the apartment complex has receive support from a number of organizations, some residents in this quite section of town are less than enthusiastic about the project, said. Wexler.

"Many residents had a lot of questions like 'are these people going to be on drugs or are they going to be on drugs or are they cgoing to be criminals' . . . We just answered the questions as best we could,," he said.

The excutive director added, however, that the apartment project has been greeted with "fewer concerns" than when the original group home was proposed elsewhere in Alexandria.

"It's a good sign. People are no longer afraid of the mentally retarded," said Wexler.