Editor’s note: This article by Patricia Kime originally appeared on Military.com, a leading source of news for the military and veteran community.

On his final full day in office, President Donald Trump signed an executive order directing the Defense Department to study the environmental exposures of U.S. troops who served in Uzbekistan in the early 2000s, a step that could pave the way for ill veterans to receive benefits from the Department of Veterans Affairs.

Trump's penultimate executive order requires the DoD to assess pollutants at Karshi-Khanabad Air Base, or K2, from Oct. 1, 2001, to Dec. 31, 2005 -- the period when American personnel served at the former Soviet and Uzbek base in support of the Afghanistan War.

According to veterans assigned there, the base was a toxic cesspool where a thick black liquid seeped through the soil, and a runoff pond and the ground glowed the same shade of green as a glow stick.

"One of my favorite running trails was a one-mile loop that wound its way through a radiation field. There was a sign that said 'Radiation, stay out,' and you ran around," said Mark Jackson, a former Army staff sergeant.

"The clues were there [of contamination]," he added. "One of our jokes was there were signs -- there were actual signs."

A number of veterans who served at the base have developed cancer or other serious illnesses, including Jackson, 43, who takes medication to compensate for a destroyed thyroid gland and has anemia, likely caused by radiation exposure.

A poll of members who belong to a Facebook group devoted to K2 veterans found that, among 1,200 who completed a survey, the cancer rate was 14%. Across the U.S., the probability that men will develop an invasive cancer before age 49 is one in 29; for women, it's one in 17.

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The contamination and suffering was first reported in December 2019 by the McClatchy news organization. Documents obtained by the news organization showed that the base was contaminated with missile propellant, solvents, fuel, lubricants, trace amounts of chemical weapons and depleted uranium.

The executive order requires the Pentagon to identify the pollutants and their exact locations, the time frame for exposure, and the names of service members who likely were exposed. The DoD also is required to conduct an epidemiological study of the health conditions diagnosed in K2 veterans to determine whether any illnesses should be added to a list that would automatically qualify an affected veteran for VA benefits.

The order stops short, however, of declaring any illness found in K2 veterans as being presumed to be related to service at the base -- a designation that would have accelerated the VA benefits application process for affected veterans.

Instead, the order is a "first step" on a path to medical care and compensation for veterans or their surviving families, said Kim Brooks, whose husband Tim died of cancer in 2004 after serving at K2.

"Essentially, the executive order is a starting point from which we can continue to get our veterans recognition," Brooks said. "We've crossed that finish line, but we have more work to do."

Jackson, who served at K2 from July 2003 to April 2004, played a pivotal role in developing the executive order and helped attract the attention of former Acting Defense Secretary Christopher Miller, a K2 veteran himself.

"There's never one person who does things like this, and so many other people were involved," said Jackson, the legislative director for the nonprofit Stronghold Freedom Foundation, which was established to advocate for K2 veterans. "It's a spider web of connections."

According to the order, the DoD has a year to begin its study and must submit a report to the president through the VA.

Meanwhile, according to Brooks and Jackson, veterans and families will continue to fight for a presumptive service connection.

"We're not going to stop ... because there's no presumption. We know. We know we are sick, and the VA is not going to be allowed to do this piecemeal, case by case like we are doing now. And they know. I'm reading their classified documents. They knew it in 2002."

Despite his health problems, Jackson said he understands why the U.S. used the well-placed base and said he would deploy there all over again to execute the mission. He simply believes that veterans sickened by their assignment at K2 deserve care.

"When you volunteer for the military, you volunteer to possibly die. As it turns out, I got shot; it's just a real slow bullet," Jackson said.