The former Army specialist says he developed a number of health conditions years after he served in the 21st Chemical Company. "I done lost my skin, my glands don't work. I don't sweat, so I just have to live with it," Mayo told CNN's "The Lead with Jake Tapper."
"I started losing my hair and then my skin started getting bad, then the knots started rising on my head ... that was something to be scared of, you know. You didn't know what was going to happen next."
VA records show that Mayo, 80, sought coverage for medical conditions that include a type of lymphoma often associated with exposure to Agent Orange.
Mayo was drafted in 1959 and sent to Fort McClellan in Alabama, where Mayo says mustard gas was tested on his skin and he participated in radiation tests without protective gear.
"We went out to this radiation area and we was there for about three hours. No kind of instruction or nothing. They just gave us the badge and told us to pin it on us," Mayo says of the radiation test, during which he wore a device to monitor exposure. Fort McClellan was closed in 1999 after the Environmental Protection Agency labeled it a "Superfund site," a term used for areas so contaminated by hazardous waste that they pose a threat to human health.
The Department of Veterans Affairs argues there's no proof Mayo's medical issues are a result of his Army service, which means it doesn't have to cover the high cost of care. Other veterans who served at Fort McClellan say they have gotten the same response.
According to the VA, veterans deployed to Vietnam have a presumption of exposure to chemicals commonly used in combat, which allows them to access benefits more easily. But service members who say they were exposed to the same chemicals on US soil bear the burden of proof.
Mayo's daughter, Wendolyn Lacy, said there are many soldiers and their doctors reaching out to Congress asking for help. "It just seems like it doesn't matter right now. Fort McClellan was a war zone within itself. They were training there but they ended up with the same conditions just like someone who was, you know, on the front line," she said.
New York Rep. Paul Tonko, a Democrat, has introduced legislation to help ease access to care for Fort McClellan veterans, but the bills have not passed.
When reached for comment regarding Fort McClellan veterans, the VA told CNN it reviews claims case by case, but it "has no evidence of a widespread contamination" on the base and has no plans to create health care policies to address this group of veterans.