The Congressional Budget Office said Thursday that legislation that would extend the 9/11 Victim Compensation Fund bill would cost American taxpayers $10.2 billion over the next decade.

The cash goes toward first responders and their families, along with neighborhood victims, who were sickened from the downed Twin Towers and other 9/11 related sites.

Sept. 11 first responders, along with former “Daily Show” host Jon Stewart, have been lobbying this year for a permanent re-authorization of the fund.

Currently, victims have only until December 2020 to file claims.

In February some victims’ payments were slashed because the current fund was running out of money. The new bill would refresh the coffers and allow for future victims to file claims, with the expiration date extended to 2090.

The CBO’s outlook just looked at the cost of the legislation over the next 10 years.

The agency admitted there are areas of uncertainty in the figures.

For instance, the report’s writers had to estimate how many people were exposed on Sept. 11, 2001. The New York City World Trade Center Health Registry suggests that 410,000 people, including 90,000 first responders, were directly exposed to “environmental contaminants” after the terror attacks.

Currently about 95,000 people – of which 80% are first responders – participate in the WTC Health Program, the report said.

Another factor the CBO had to look at is how many incidences of cancer are expected among the exposed population. The tally in Thursday’s report estimates that cancer chances would be 11%, on average, higher among first responders and recovery workers, compared to the general public.

It would be 6% higher among other eligible survivors, such as children who went to school in nearby neighborhoods.

The CBO’s estimate also points out that cancer cases are up among the 9/11 claimants. From 2011, when the fund began, and May 2019, 37% of the claims and awards came from cancer cases.

When looking at just the last two and a half years, 45% of claims and awards went to cancer victims.

Exactly one month ago, “Daily Show” host Stewart shamed members of a House Judiciary subcommittee for not attending testimony on the matter, including some from retired detective Luis Alvarez, who has since passed.

Alvarez talked about how he had come down to DC to push for the bill on the eve of his 69th chemotherapy treatment for liver cancer. Alvarez never got a final round of chemo, with doctors putting him in hospice care. He died on June 29.

Even before the CBO score dropped, House Speaker Nancy Pelosi told reporters Thursday that a planned Friday House vote is a go.

The House bill, sponsored by Rep. Carolyn Maloney (D-N.U.), currently has 332 co-sponsors and is expected to pass overwhelmingly.

Senate Majority Leader Mitch McConnell committed to a group of first responders in late June that the Senate version would get a vote in August. It has a filibuster-proof majority and is also expected to pass.