Less than one dollar of five in the $1.6 billion "Superfund" has been used to clean up the nation's worst toxic-waste dump sites, and more than half of the fund has been spent on "administration and nonpriority sites," according to a citizens' group that studied Environmental Protection Agency records for several months.

The National Campaign Against Toxic Hazards, an umbrella organization established two years ago to fight for a larger Superfund, found that 16 percent of the fund has been spent on physical cleanups.

At that rate, more than 90 percent of the 812 sites on the government's priority list will not receive long-term cleanup funds by the time the law is 5 years old, the study said, suggesting that "millions of Americans will wait decades for EPA to clean up their poisoned communities."

EPA officials denied the group's findings, calling the report an "unfair representation" that does not take into account millions of dollars spent for environmental and engineering studies before bulldozers move in.

"We would argue that that's part of the cleanup," said Russ Dawson, a spokesman for EPA Administrator Lee M. Thomas. "It may be somewhat invisible, but that study is the first part of the cleanup."

Michael Podhorzer, who headed the organization's research team, said a computer analysis showed that 29 percent of the Superfund has been spent on such studies. "Obviously, they're important," he said. "But EPA itself shows that the vast majority of the cost of cleanup is in construction. It's construction that gets the site cleaned up."

The study is likely to fuel a contentious battle over the Superfund, which is up for renewal this year. The administration agrees that more money is needed, but the EPA contends that it cannot spend more than $5.3 billion over the next five years. The Senate is considering a $7.5 billion bill, and the House version is expected to be larger.

Two years ago, the Superfund was at the center of a storm at the EPA. Allegations of impropriety and mismanagement of the program eventually forced an overhaul of the agency's management but did not end criticism that the Superfund was moving too slowly.

Podhorzer's analysis found 56 percent of Superfund money being spent on administration, including "management support and interagency support," and on emergency work at sites not dangerous enough to make the priority list.

He said the group did not consider those expenditures inappropriate, however, "because the cutoff for getting on the priority list is so arbitrary."

"The overarching problem is that there's not enough money to go around," Podhorzer said. "EPA is intimately familiar with how little progress it is making, and yet it politically resists getting enough money to do the job."

The EPA does not have a single system for tracking Superfund expenditures and does not break down expenses in the same way that Podhorzer's group did, but Dawson said the agency's figures show that it has taken some action at 370 priority sites.

An illustration of the difference between the EPA's count and that of the National Campaign Against Toxic Hazards is the Baird and McGuire Superfund site in Holbrook, Mass. A former chemical-company tank farm, it has ground water contaminated with various industrial chemicals.

The EPA lists it as one of the 370 sites at which it has taken action, including putting a clay cap on part of the area and installing some fencing and recycling pumps to prevent spread of ground-water contamination.

But studies to identify more permanent solutions have been delayed repeatedly, and the campaign's study counts Baird and McGuire as a site at which no cleanup funds have been spent.

"The EPA said they're understaffed and they have a bottleneck at their labs," said Leah Abbott, who lives near the site, which she said is "still leaching chemicals."

The community's wells were ordered closed recently, and Abbott said she buys drinking water even though the EPA has assured residents that alternate water supplies from a reservoir fed by a river near the site are safe.

"How they can find high levels of contamination on both sides of the river and say it's safe in the middle is beyond me," Abbott said.

Another site, which the EPA agrees is not likely to be cleaned up soon, is the Powell Road Landfill in Dayton, Ohio, where thousands of drums of industrial solvents are interred.

The site is in the middle of Dayton's well field, which the city had planned to expand into a regional water supply for more than 500,000 people.

"Everything is on hold," City Commissioner Mark Henry said. He said that no formal studies have been conducted at the site, although contamination has been detected, and that he has no estimate of costs to clean up the landfill.

"I know that it will cost Dayton $30 million if we lose a well field," he said.