After the last war with Iraq, U.S. leaders resolved to curtail the nation's dependence on foreign oil. Soon, dozens of new fuel stations opened around Washington catering to the new politics: They pumped neither gasoline nor diesel, but natural gas.

"It's readily available domestically, [so] we avoid going halfway around the world to get it," Ajit Ratra, a manager for Washington Gas, announced in the mid-1990s amid a push that would create 38 stations for the fuel, described as "cleaner, cheaper and safer" than gasoline.

It never quite worked out.

The stations were supposed to serve burgeoning fleets of natural gas vehicles, as envisioned in new national energy legislation. But last month, as another war in the Persian Gulf set oil prices aflutter, a quiet retreat was underway on the alternative fuels front. Washington Gas announced that another of its natural gas pumps would be closing.

Today's closure -- of a one-pump operation in East Potomac Park -- marks the 14th such shutdown. Stations in Arlington and Prince George's counties also closed recently.

As it turned out, the revolutionary switch to natural gas forecast for the region has been largely limited to some transit buses, a few taxis, and some sedans operated by federal or local agencies.

"We built the stations anticipating greater usage," Washington Gas spokesman Tim Sargeant said. "It is a market that continues to mature very slowly."

Natural gas has long been considered a prime candidate to replace gasoline, so why the experiment fell short -- in this area and elsewhere -- is a matter of dispute. But the shortage of refueling stations is central to the chicken-and-egg conundrum underlying the alternative fuels effort: Without more stations, more natural gas vehicles are unlikely, and vice versa.

"We're making do, but it's a hardship," said Eric Smith, transit operations manager for Arlington County, which is sending most of its natural gas buses 20 minutes farther away to be refueled because of a recent station closure.

"Where are we supposed to get it now?" asked a District parking enforcement worker recently as he refilled his city-owned natural gas Honda Civic at a pump in East Potomac Park that is closing today.

Making the effort more difficult, natural gas cars and refueling stations cost significantly more than their diesel and gasoline counterparts.

Refueling stations for compressed natural gas are expensive to build because the fuel must be kept in pressurized tanks, which cost about $240,000 each in this area. And though starting prices for a gasoline Honda Civic run from $13,000 to $17,000, those outfitted for natural gas start at $20,000.

"That's a bitter pill to swallow, even if you are committed to the environment and reducing our dependence on foreign oil, as we are," said Fredric Hiller, equipment division chief for Arlington, which runs 11 natural gas buses and about a dozen sedans and pickups that can run on gasoline or natural gas.

The energy legislation passed after the 1991 Gulf War was supposed to give the new fuel technologies a boost. It called for federal and state fleets to increase their percentages of cars, vans and pickups that run on alternative fuels. The idea was to help generate public interest and motivate companies to build natural gas refueling stations and cars.

The legislation's ambitious goal: By 2000, 10 percent of the fuel for the nation's cars, pickups, vans and SUVs would be something besides gasoline or diesel; and that by 2010, 30 percent would.

"There was this feeling that this would be the wave of the future," said a U.S. Department of Energy official.

It wasn't. According to a 2001 federal report, less than 3 percent of motor fuels consumption had been replaced with alternative fuels, and the large majority of that came from substances such as ethanol blended with gasoline in conventional vehicles. And the number of natural gas vehicles rose from 32,000 in 1993 to 129,000 in 2002, according to estimates by the Energy Information Administration.

"That's not the type of growth that anyone wanted or expected," said Gil Sperling, counsel to the Natural Gas Vehicle Coalition.

The natural gas vehicles most likely to be seen locally these days are those in governmental fleets. They have signs identifying them as "CNG," for compressed natural gas vehicles, or "NGV," for natural gas vehicles.

Fleet managers saw virtues and drawbacks in the vehicles.

There are believers: Metro, for example, recently decided to purchase hundreds more natural gas buses, and Montgomery County also is adding to its fleet. And there are doubters: Fairfax and Prince George's counties have tried and largely rejected the natural gas experience.

"When alternative fuels came up in the '90s, we were very interested in cleaning up the air and trying to contribute in any way in getting the U.S. off foreign oil," said James D. Gorby, director of the vehicle services department in Fairfax County. "But we didn't have a good experience."

Although county planners knew that natural gas stations are sparse and that the vehicles are more expensive and often have less cargo space because their tanks are larger, Fairfax purchased 72 cars, pickups and buses that could run on the fuel. Now the county is down to 44, which officials said are unlikely to be replaced given past experiences of cars and buses breaking down, in part because the natural gas pressure is difficult to control in changing temperatures.

"The school bus drivers especially were not happy," Gorby said. "We decided to try other clean alternatives."

Others, however, are willing to keep trying. Although local governments have not been compelled to purchase natural gas vehicles, the added cost of acquiring them sometimes is recovered with state and federal grants.

Most of the D.C. parking enforcement fleet runs on natural gas. And one of the biggest investors is Metro, which has put up substantial money to switch to natural gas buses.

Although a new bus that runs on compressed natural gas costs about $370,000, or $30,000 more than a new "clean diesel" bus with improved emissions, Metro's board recently decided to purchase 250 more. Metro also is spending about $40 million to retrofit two refueling and maintenance stations to accommodate natural gas buses.

Officials said the benefits relate to the environment and energy security.

"It's well worth it," said Metro board Chairman Jim Graham, noting that each bus advertises its unusual fuel source on its side. "These are traveling billboards that are a little reminder that we could be doing all of this differently."

D.C. Public Works employee Dwight Dent fills up a van at the natural gas pump at East Potomac Park, which shuts down today. Washington Gas planned to have 38 stations for the fuel, called cleaner and cheaper than gasoline, to curtail dependence on foreign oil.