THOSE WHO MUST regularly endure automotive life on the Capital Beltway from crawl to sonic boom may well shudder at the thought of a second beltway in their future. But it's more than just a pipe dream of the highway lobbies; thoughtful transportation experts around the region are looking

more and more to an outer beltway as one necessary response

to the congestion of tomorrow.

Only last week the Fairfax

County Board of Supervisors became the first local governing

body in the region to endorse the concept -- and the vote was unanimous. At the same time a committee of county residents began organizing to generate support for the idea.

It's not a new idea by any means -- which is why the residents' organization is critical. For more than 20 years, proposals for some kind of outer beltway bypass have been floated and then gunned down by public resistance. But 20 years from now, this region will be coping with the side effects of all the development taking place along the outer edges of the metropolitan area. Even if a project were agreed to this morning, you could pretty much count on seeing the 21st century before seeing the ribbon-cutting.

The precise path remains to be decided, but tentative proposals by Virginia highway officials envision a beltway perhaps 10 miles outside the existing one. It would swing from somewhere near I-70 or I-270 in the Frederick area into Virginia's Prince William, Loudoun and maybe Stafford counties and around to I-95 north of Fredericksburg.

There's the not-so-slight matter of the tab -- maybe $800 million. For this and other reasons, Fairfax residents will be looking for help from neighbors on both sides of the Potomac. Anybody in the possible path of this project won't be eager to sign up, either. But already some of the more visionary leaders in Northern Virginia and its outskirts understand the importance of a coordinated approach that will address what is already a spreading transportation problem. They could use constructive criticism -- and the Fairfax action opens the floor for precisely that.