The U.S. government is expected to compensate 9/11 rescue workers and residents living near Ground Zero amid concerns of a possible link between cancer and the toxic World Trade Center rubble.

When the towers fell, thousands of New York's finest rushed to the scene, where smoldering debris made it difficult to breath. Many law enforcement and medical workers stayed to help for months.

Now, more than a decade later, many people who helped as well as those who lived near the site say the toxins from the destruction gave them cancer.

"For first responders and residents, they knew the air wasn't safe, not withstanding what the EPA was saying," attorney Michael Barasch said.

"But it didn't matter," he continued. "They were there to help save whoever could be saved."

At first, federal government officials refused to pay for medical bills saying there was no proof. But new evidence has emerged that has changed all that -- on the eve of the 9/11 anniversary.

The government is expected to announce that about 50 cancers will be covered by a nearly $3 billion fund set up for victim compensation.

"The first responders who were there for us, we're now going to be there for them," Barasch said. "We're going to compensate them and help provide treatment."