For example, Sen. Dianne Feinstein, D-Calif., said at the hearing, "If [the bill's cost] isn't known before the New Year, I don't know how we can consider this bill on the floor in January." Ms. Feinstein supported the bill when it came before the Judiciary Committee in May.

And Senate Minority Leader Harry Reid, D-Nev., said on the Senate floor Wednesday, "This bill is not acceptable in its current form. It's not even close."

The bill would remove claims for damages from exposure to asbestos in the workplace from the courts to special panels under the aegis of the Department of Labor.

Under the legislation, claims would be paid based on 10 different levels of compensation, with the sickest getting the quickest airings of their claims–and the most monetary damages.

Yesterday's hearing was convened to deal with the findings of the Bates White consulting firm that the proposed fund would face claims of between $301 billion and $561 billion and go broke within three years.

The Congressional Budget Office in August estimated the long-term costs of the fund at between $120 billion and $150 billion, and Dr. Douglas Holtz-Eakin, retiring director of the CBO, reiterated that estimate in his testimony yesterday.

CBO's estimate of the claims likely to be filed under S. 852 for compensation for injury resulting from asbestos exposure is based on analyses by a number of experts who studied the legislation and similar proposals in the 108th Congress, he said

The Bates White study "grossly overestimated the population at risk from asbestos disease," Denise Martin, senior vice president at the National Economic Research Associates in New York, added at the hearing.

Laura Welch, medical director at the Center to Protect Workers Rights, said Bates White had assumed a barber who started work in 1970 had the same risk of asbestos-related cancer as a shipyard insulator during World War II. "Clearly this is not the case," said Ms. Welch.

Charles Bates, chairman of Bates White, countered that a large number of people who do not currently have valid court claims for asbestos-related injuries would file for compensation if the fund is established.

He said millions of people were alive who had worked in occupations covered by the proposed legislation, and "the act greatly increases the incentives to file" claims.