We're delighted to see the creative approach of New Mexico's senators toward making the Valles Caldera a more public-accessible piece of public land. Their bill, though, will have to be carefully crafted, and diplomatically guided, to get through a budgetary gun-shy Congress.

The ancient-volcanic caldera, a prime stretch of woods and meadows up beyond Los Alamos, was bought by the federal government a decade ago for $101 million; money gained through the efforts of then-Sen. Pete Domenici, Senate colleague Jeff Bingaman and then-Rep. Tom Udall. But Domenici was the main player — and, in his role as fiscal watchdog, he insisted that the 89,000 acres pay their own way: The land became a "national preserve" on which grazing-fee ranching would continue, hunting fees would be stiff and other tourist activities would keep cash registers ringing.

The preserve's board of directors has done its best to achieve Domenici's goals — but there just isn't enough money being generated. Meanwhile, entry to many parts of the property remains restricted.

Bingaman and Udall, who succeeded Domenici in the Senate, figure one way to allow America a better look at what we bought is to put it under National Park Service management; it still wouldn't be a park per se, goes the pitch — but instead of having to sign up for semi-exclusive events allowing us into the place, New Mexicans and visitors from far and wide would just pay the kind of park-entrance fees we do at nearby Bandelier National Monument. In time, there might be a scenic road through it.

But how compatible are tourism and ranching? There's talk of some kind of token cattle operation, perhaps as an educational program; educational for city dudes who'd learn how hard the ranching life remains, and educational for regional ranchers if it becomes a model for grazing that doesn't destroy land and streambeds.

Roads? Demonstration ranches? Campgrounds? Picnic tables? They carry price tags. Our senators' Capitol Hill colleagues are sure to raise eyebrows about the cost of another quasi-national park; the ones we have already are being tromped to death and they're woefully understaffed ...

Is there a selling point in proposing resort hotels and other lodging? Or does that defeat the preservationist notion that prompted the federal purchase heading off private resort development? Hearings on this bill are bound to bring out commercial-development champions as well as fiscal hand-wringers.

This will be a test of Bingaman's congressional clout as chairman of the Senate Energy and Natural Resources Committee — and of Udall's celebrated nature-conservation advocacy. We wish them both well.