ELIZABETH Hanford Dole seems to have worked a minor miracle. In less than a month in office as secretary of transportation, she has moved a mountain: yesterday she stood in front of Union Station--America's barely living monument to governmental project-mangling--and announced an agreement, complete with federal cash at the ready, to rescue, revive and redevelop this city's once-grand railroad terminal.

No new task force, no vague study, no buck-passing --but an agreement to provide $70 million in existing DOT and Amtrak funds to start right away making Union Station "alive and vibrant with people . . . a center of activity for our city of Washington and for this nation." It won't--can't--happen overnight, but after all the nights it has been in near-collapse from abuse, neglect and federal misdirection, there is light at the end of the concourse: officials figure on five years for complete rehabilitation of the station, with shops, restaurants, office space and other signs of real life--including train tracks that people can actually see and get to, just like in the old days.

There are some losers, of course: the rats, bats and underwater creatures that came to know and love the abandoned, rain-flooded upper regions of the station will no doubt seek relocation assistance; and spelunkers won't have that huge crater in the ex-visitor-center floor to explore anymore.

So be it. Mrs. Dole's agreement has the enthusiastic as well as financial support of Mayor Barry, too. He has committed $40 million to finish the garage that goes with the station. Also in high gear for the project are Amtrak President W. Graham Claytor Jr. and Federal Railroad Administrator Robert W. Blanchette.

Clearly this is no inexpensive mission, but that has been the worst part of this incredibly bad saga all through the years: the costs of federal failures long ago went through the roof (literally, if you were to look up from ground level) and the lease won't quit no matter what. It has taken keen interest, political courage and a sense of Union Station's historical and local significance to cut the waste and press to get a necessary job done with efficiency and good taste.

Credit is due Mrs. Dole's predecessor, Drew Lewis, who first tackled this mission, got some serious planning done and spoke out forcefully for federal action. Now Mrs. Dole has surprised and delighted everyone in federal and local Washington with her swift, enthusiastic and skillful action to rescue a landmark and create an important economic anchor in a part of this city that can and should flourish in the future.

Not a bad few weeks' work.