More than two-thirds of the nation's hazardous-waste disposal facilities have apparently decided to close rather than comply with environmental laws, the Environmental Protection Agency announced yesterday.

Agency figures show that 492 of an estimated 1,600 landfills, ponds and waste lagoons operating under short-term permits have certified that they have installed equipment to check for leaks and have enough insurance or financial resources to pay for any contamination that might occur.

By law, toxic-waste facilities had to meet those requirements by Nov. 8 or immediately stop receiving waste and prepare to close.

Last month, the EPA estimated that about 500 disposal operations would not meet the deadline and would be forced to close. According to preliminary figures, the actual number was more than 1,100.

"It is a surprise to us," said Gene Lucero, an EPA enforcement official. "The maximum we had estimated was that 50 percent would not comply, and we thought that was high."

But environmentalists and some industry officials said the dropout rate should not have been a surprise.

In addition, they warned that the EPA will have to move quickly to assure that the closed dumps do not accept waste illegally or wind up on the "Superfund" list for federal cleanup.

"There were a lot of pits out there that nobody ever intended to permit and that ought to be put out of business," said Richard Fortuna of the Hazardous Waste Treatment Council, a trade association for the recycling and treatment industry. "Those disposal pits were designed to leak, and people knew if they put monitoring wells in, they'd get bad news."

Linda Greer of the Environmental Defense Fund called the figures "an amazing indictment of what the status quo was. There were so many dumps out of compliance that were just waiting for somebody to catch up with them.

"The EPA is going to have to do a bang-up job to keep those facilities from becoming Superfund sites," she said.

Most of the sites expected to close are small operations, and agency officials acknowledged that some will have difficulty meeting closure standards without courting bankruptcy, especially if significant contamination is found.

Lucero said the dwindling number of facilities suggests that industries are turning away from land disposal of toxic wastes in the face of increasingly stringent laws.

"My sense is that a number of facilities used this deadline as the point to make some basic business decisions," he said. "They looked at the potential liabilities and the problems of getting insurance and decided it's time to think about some other ways to deal with these wastes."

Agency officials warned last year that the compliance deadline would leave the nation short of capacity to dispose of toxic wastes.

Yesterday, however, Assistant Administrator J. Winston Porter said preliminary assessments indicate that "availability of places to store or dispose of hazardous waste has not been seriously affected in the near term."

According to Lucero, some industries have made plans to recycle their wastes and others are looking at temporary storage in above-ground tanks.

The EPA said 50 of the 59 major commercial toxic-waste landfills met the deadline, as did most facilities operated by large chemical companies and other major industries.

The EPA announcement came as the House considered a bill to expand toxic-waste cleanup activities by more than sixfold over the next five years, amid almost universal agreement that the problems of toxic contamination are far greater than they appeared in 1980 when the Superfund cleanup program was established with a five-year budget of $1.6 billion.

The Senate has approved a $7.5 billion Superfund bill.

The House suspended consideration of its $10 billion version yesterday after completing work on all but the most controversial provisions: who will pay for it and whether citizens will have the right to sue polluters for damages.

The chamber adjourned just short of a vote on a pair of amendments that would kill a broad-based corporate tax approved by the Ways and Means Committee and shift the primary responsibility for financing Superfund back to the oil and chemical industries, which have borne most of the cost in the past.

Financing has emerged as the most contentious issue in the battle to renew Superfund, which technically expired Oct. 1.

The Senate has already approved a corporate excise tax, and oil and chemical firms have lobbied heavily to preserve the tax in the House.

But almost every other business group has lined up against the tax, characterizing it as a national sales tax, and the White House has threatened to veto Superfund if the corporate levy is included.

When it returns to Superfund Tuesday, the House will also take up an amendment that would grant victims of exposure to hazardous waste the right to sue for damages in federal court. On that provision, the business community is united in opposition.

A group of 46 trade associations urged the House to defeat the provision, calling it an "unsound proposal" that would divert attention from toxic cleanups.

The House has been less than receptive to industry arguments on Superfund.

In action late Tuesday night, legislators overwhelmingly rejected, 330 to 62, an amendment that would have sharply restricted polluters' liability for cleanup costs.

By a much narrower margin, 183 to 166, the House adopted an amendment that would require plants to report emissions of substances suspected of causing long-term health problems.

The original bill would have required reporting only on substances capable of causing immediate injury or death.

"That's like outlawing hand grenades because they're dangerous, but saying time bombs are okay," said Rep. Gerry E. Sikorski (D-Minn.), the amendment's sponsor.