U.S. special operations forces who deployed to a military site in Uzbekistan shortly after the 9/11 attacks found pond water that glowed green, black goo oozing from the ground and signs warning “radiation hazard.”

Karshi-Khanabad, known as K2, was an old Soviet base leased by the United States from the Uzbek government just weeks after the Sept. 11, 2001, attacks because it was a few hundred miles from al Qaeda and Taliban targets in northern Afghanistan.

The base became a critical hub in the early days of the war to provide airdrops, medical evacuation and airstrike support to U.S. ground forces in Afghanistan.

But K2 was contaminated with chemical weapons remnants, radioactive processed uranium and other hazards, according to documents obtained by McClatchy.

At least 61 of the men and women who served at K2 had been diagnosed with cancer or died from the disease, according to a 2015 Army study on the base. But that number may not include the special operations forces deployed to K2, who were likely not counted due to the secrecy of their missions, the study reported.

As part of McClatchy’s continued investigation into the rising rates of cancers among veterans, members of those special operations forces units who were based at K2 are speaking out for the first time because of the difficulty they have faced in getting the Department of Veterans Affairs to cover their medical costs.

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“After returning from combat years later, we are all coming down with various forms of cancer that the [Department of Veterans Affairs] is refusing to acknowledge,” said retired Army Chief Warrant Officer Scott Welsch, a special operations military intelligence officer who deployed to K2 in October 2001. He was diagnosed with thyroid cancer in 2014.

Some of those who served at K2 are about to submit a letter to Congress asking for help.

Read the rest of this Tara Copp article at McClatchy DC.