Companies that clean up and manage the nation's toxic waste say they have been subjected to a new, and perhaps intolerable, danger: the disappearance of virtually all commercial liability insurance.

The disappearance has followed the collapse in the last year of pollution coverage for chemical, oil and other companies that generate hazardous waste around the country. As a result of Bhopal and other enviromental disasters, a series of court decisions perceived to have opened up potential liabilities, and a general downturn in the property-casualty business, insurance companies have turned away in droves from covering firms that generate waste.

Although hazardous-waste-cleanup-industry officials say their claims have been infinitesimal, they say they have suffered from the same squeeze afflicting the waste generators. Rep. James J. Florio (D-N.J.), a critic of insurance companies and a major sponsor of Superfund -- legislation mandating the cleanup of dangerous waste sites, said the insurers are lumping "contractors in the same category as those who are the dumpers."

For these contractors, however, the insurance problem also is complicated by federal and state laws that they say effectively make them the scapegoat for conditions at hazardous waste sites over which they may have no control.

Under the 1980 Superfund law , for instance, cleanup contractors and engineers say that they can be held legally responsible for pollution that already has occured. Furthermore, they say, firms are exposed to third-party suits, allowed under state laws, that threaten damages much higher than the value of the contracts for the cleanup.

The net result of these potential liabilities is that insurance companies profess unwillingness to provide coverage to cleanup firms because they say they cannot measure the risk involved.

Paul Genecki, senior vice president of Victor O. Schinnerer & Co., an underwriting firm heavily involved with engineers, said that, by the end of the year, engineers and contractors wanting to do cleanup jobs for federal or state bodies won't be able to buy any liability insurance at any price. The small circle of firms involved in the private waste-management business are better off, but not by much. Jeffrey Klein, a vice president at Kidder Peabody who follows the industry, said insurance still can be obtained by well-established firms, although at triple or quadruple the premiums they once paid. Companies, which until recently were able to obtain $60 million to $70 million worth of coverage, now can buy only about $10 million, he said.

The insurance squeeze is only the latest twist to affect the waste service and management industry, which has had to confront continuously changing technologies and regulations in less than a decade of existence.

The industry appeared virtually overnight with passage of the Resource Conservation and Recovery Act in 1976, which established a federal regulatory program for the management of hazardous substances created by private industry. Up until that point, waste generators generally disposed of their waste on the site or with municipal and residential refuse.

The establishment of a $1.6 billion Superfund, a five-year program designed to clean up the most dangerous toxic waste sites, further accelerated the expansion of the market for engineers and contractors hoping to get into the game. Congress is debating legislation that would extend Superfund. Regardless of the exact level of funding agreed upon, industry officials expect continued growth in this lucrative market.

John Schofield, senior vice president of International Technology Corp., a major waste management firm in California, said the insurance squeeze in the pollution field could play a major role in forcing the expansion of the cleanup market. Generators of the estimated 265 million metric tons of hazardous waste produced annually are likely to be much more conscious that they need to dispose of the substances carefully or else they risk the future of their firms, he said.

Schofield said that the entire management and cleanup industry, estimated at about $1.5 billion in 1984, should grow to about $12 billion to $15 million by 1993. "But just as the market is picking up steam, it gets the added crunch from the insurance squeeze and Bhopal," he said, citing the Union Carbide Corp. disaster in India that has created so much nervousness in the industry.

Industry executives say this crunch could have significant social repercussions. Congressional moves are afoot to limit the liability of cleanup firms, but until then, industry officials openly speak of an unwillingness of firms to enter or remain in the cleanup market without the protection of insurance.

Warren Diederich, chairman of Industrial Builders, a North Dakota contractor that has done some cleanup work, said he did not bid for a recent Superfund project to clean up an abandoned asbestos mine because the company was unable to find liability insurance. Discussing a future cleanup project in Denver, Diederich said, "Right now, there's no way we can do the job, not our firm or any other firm aware of the liability problem."

According to industry executives, their ability to weather the insurance crisis depends on a number of factors, most immediately success in winning from Congress and state legislatures curbs on the extent and amount of the liability that firms would assume.

The industry has launched a concerted lobbying effort to persuade Congress to enact such curbs in its extension of Superfund. Their leverage is considerable: the warning that they will abandon cleanup work if relief is not granted.

CH2M Hill is a large consulting engineering firm with about 15 percent of its total work in hazardous waste and treatment, including extensive Superfund work. But William A. Wallace, the firm's director of solid and hazardous waste management, said his company will not risk all of the firm's revenue -- $204 million in 1984 -- for the liabilities arising from that portion of his business. "We're prepared to walk away from all our hazardous-waste business if this continues this way," he said. A recent study for the Associated General Contractors of America similarly concludes that no firm should think of getting into cleanup "unless it is willing to risk its entire net worth."

The cries have not gone entirely unacknowledged. The recent Superfund bill approved by the Senate calls for the government to indemnify contractors against third-party liability for damages that are not their fault. The comparable House version, which has not yet reached the floor, takes a different route. The House proposal exempts cleanup contractors from federal, state and common law for damages caused by the release of toxic substances that were not caused by contractor negligence.

Given the labryinthine progress of the Superfund legislation, industry lobbyists and congressional staffers say it is unclear which proposal, if any, will be adopted in conference. And as it stands right now, they add, even the limitations under consideration may not be strong enough to entice the insurance industry back into the market.

Echoing a common insurance industry theme, Genecki said the real problem is the U.S. court system, which he said currently offers unpredictable -- and hence uninsurable -- damage awards in the pollution area. "We know that the courts are giving the money away, and we can't afford it," he said. This kind of talk puts legislators on edge. Counters one congressional staffer involved in Superfund: "The insurance industry is totally unreasonable across the board. They basically want no liability so they don't have to pay any claims."

Ironically enough, despite the short-run woes, the insurance squeeze could prove beneficial for the cleanup industry and the environment in the long run, executives and analysts say. With normal insurance scarce and expensive, companies will step up their risk-reduction programs, including the elaboration of proper safety procedures, industry executives say. For instance, Kidder Peabody's Klein predicts a greater emphasis on incineration and on chemical or physical processes to detoxify substances, rather than storing the substances in the ground, where they might seep from their containers.

"It's going to force a shakeout of the companies that are not strong," Klein said of the shortage of liability coverage. However, he said, the companies that remain will be "able to raise prices to a level commensurate with the services they offer. The profit potential is much more attractive."