IT'S STILL spooky inside the skeleton of Union Station, and surely the hangers-on among the four-legged, feathered and other moving creatures that have been dwelling in the swamps and crannies of the place aren't yet heading for the suburbs. But the missionaries of metamorphosis -- 400 workers restoring the grandeur of the old terminal in preparation for a triumphant revival in perhaps 15 months -- are making their presence known in visible and appropriately awesome ways. After all those hideously expensive architectural orgies and the coma of neglect that ensued, Union Station is actually on a comeback.

The serious good news broke only days after Elizabeth Dole took office as transportation secretary in 1983. She went up to Union Station and announced an agreement -- complete with private as well as public money to do the job. It called for a tasteful restoration that would combine the past glory of the place with contemporary attractions: a variety of restaurants, 100 shops, a nine-theater cinema and office spaces. Gone at last will be the enormous pit that zany bureaucrats from the bicentennial days dug in the central hall when they turned the whole place into a vast, unused "visitor center." Returned to the front of the building and made accessible will be -- fancy this -- the train tracks, much the way they were in the station's heyday.

Developers say they have leased about 60 percent of the retail space so far, and are being selective about the tenants they choose. Already, the neighborhood around the station also is showing signs of new life; a renovation of the big post office building across the street and construction of an office building on nearby federal property are expected to spark other private investment.

The prospective return of Union Station, age 80, to a productive role in the capital city is good news.