Vernal » There was a time when hordes of visitors -- up to a half million a year -- explored the lost world of the stegosaurus, allosaurus and diplodocus at Dinosaur National Monument.

Call it the Jurassic Park Period, circa 1993 to '97.

That's when Steven Spielberg's blockbuster thriller and the first of two sequels lured millions to theaters and an average of 485,000 a year to the eastern Utah monument's main attraction: the Quarry Visitor Center.

But, in 1998, the guest count started a slow decline that accelerated in 2006, when the Park Service had to shut down and condemn the unstable building. Last year, barely 200,000 people visited the monument.

Now, a shot of federal stimulus funding is reviving hopes of reversing that descent. Call it a Jurassic spark -- one that starts with a new Quarry Center.

The current building, constructed in 1957 on shifting soil, has torqued and squeezed so hard it could pop the old entryway's dome right off, explains Wayne Prokopetz, chief of the monument's resource and research management.

"A lot of energy is being stored in the building," he says during a rare tour through the structure. "Eventually, it will release."

A different type of release -- $13.1 million in stimulus money -- means the National Park Service could break ground next spring for a new Quarry Center with a permanent visitor building down the hill.

If all goes right, says Dinosaur National Monument Supervisor Mary Risser, tourists once again will be allowed near the quarry wall -- with its hundreds of fossils -- by summer 2011.

That would please 8-year-old Charlie Birge, a Taos, N.M., resident who had to make do with handling a single stegosaurus tailbone during a recent trip to the temporary visitor center on the Utah side of the monument, which straddles the Colorado border.

"It's cool," says Charlie, a dino fan who has collected 50 models of the prehistoric reptiles. "It made me think about how it lived."

Charlie and his brother, Jack, 5, were on a two-week road trip with their grandmother Joanne Birge of Albuquerque. The trio had visited other national parks, "but this sounded like a really neat place," she says. "It's on a good route. It's a beautiful way to go from Salt Lake to Denver."

The monument -- established in 1915 by President Woodrow Wilson -- had a slow start, drawing few visitors. But when the Quarry Center opened, that changed, allowing dino enthusiasts to examine the astounding wall of bones experts had been uncovering since Carnegie Museum paleontologist Earl Douglass in 1909 found eight vertebrae of an apatosaurus (also known as a brontosaurus) in what must have been a bend in an ancient river.

Since oil and gas development rekindled a boom in the Uinta Basin in 2005 and the Quarry Center closed the next year, it has been tourists such as the Birges who have kept annual visitor numbers above 200,000 despite the dearth of motel rooms in nearby Vernal.

The Birges were traveling in an RV, so they didn't need to shell out for the few rooms not occupied by energy workers and executives who, until the recent economic downturn, held a near-monopoly on lodging.

"It's been a huge issue. You're not going to stay a couple of days at Dinosaur when you can't get lodging," says Karen Hevel-Mingo of the National Parks Conservation Association. "The [oil and gas] companies are paying prices tourists won't pay."

Prokopetz, who has worked at the monument for a dozen years, points out the Quarry Center's bulging walls, slanted floors and off-kilter doorways as he walks through offices and labs still cluttered with a first-aid kit, a National Geographic from 1978 and file boxes labeled with the names of specimens now stored elsewhere.

Some mornings, National Park Service workers would arrive to the sight of broken glass strewn across floors. Fortunately, Prokopetz says, that damage occurred mostly at night as the building cooled.

"It wasn't explosive, but the walls started buckling when the floor and ceiling moved together."

Paleontologists who worked in the lab and library repeatedly shimmed the table legs to keep specimens from rolling off tabletops. "We were worried a small earthquake or tremor would pancake down," Prokopetz says.

Paleontologists stopped work on the wall when the building closed and probably won't start again, Prokopetz says, so the quarry essentially will become a museum. The new building will be smaller but still will wrap around the quarry wall. Because the original architecture earned the building National Historic Landmark status, the new design will keep the butterfly roof and glass walls.

"You'll be able to tie the exhibit to the landscape visually," Risser says.

Administrative offices will be built into the new visitor center on the same site as the temporary one. Curatorial labs will move to Vernal, although that plan doesn't have funding.

The monument also will receive $628,000 in federal stimulus funds to replace water lines, repair trails, rehabilitate the Gates of Lodore boat ramp on the Green River and install energy-efficient windows at the park's headquarters in Colorado.

Off-highway vehicles aren't allowed, but river outfitters ply 100 miles of the Yampa and Green rivers that flow through the park, Prokopetz says. Backcountry camping also is permitted.

Tiffany McConkie, who has worked at the monument for five years, says she and other park workers used to call Friday "scary day." That's when tourists would arrive in bus convoys.

McConkie says tourists would give her a hard time when they realized the main attraction was closed. She sympathized with the visitors from Asia and Europe who came to the outback park specifically to see the famous Quarry Center, only to be let down.

In a few years, those visitors will go away disappointed no more.