As a young GI at Fort Ord in Monterey County, California, Dean Osborn spent much of his time in the oceanside woodlands, training on soil and guzzling water from streams and aquifers now known to be contaminated with cancer-causing pollutants.

“They were marching the snot out of us,” he said, recalling his year and a half stationed on the base, from 1979 to 1980. He also remembers, not so fondly, the poison oak pervasive across the 28,000-acre installation that closed in 1994. He went on sick call at least three times because of the overwhelmingly itchy rash.

Mounting evidence shows that as far back as the 1950s, in an effort to kill the ubiquitous poison oak and other weeds at the Army base, the military experimented with and sprayed the powerful herbicide combination known colloquially as Agent Orange.

While the U.S. military used the herbicide to defoliate the dense jungles of Vietnam and adjoining countries, it was contaminating the land and waters of coastal California with the same chemicals, according to documents.

The Defense Department has publicly acknowledged that during the Vietnam War it stored Agent Orange at the Naval Construction Battalion Center in Gulfport, Mississippi, and the former Kelly Air Force Base in Texas, and tested it at Florida’s Eglin Air Force Base.

According to the Government Accountability Office, however, the Pentagon’s list of sites where herbicides were tested went more than a decade without being updated and lacked specificity. GAO analysts described the list in 2018 as “inaccurate and incomplete.”

Fort Ord was not included. It is among about four dozen bases that the government has excluded but where Pat Elder, an environmental activist, said he has documented the use or storage of Agent Orange.

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According to a 1956 article in the journal The Military Engineer, the use of Agent Orange herbicides at Fort Ord led to a “drastic reduction in trainee dermatitis casualties.”

“In training areas, such as Fort Ord, where poison oak has been extremely troublesome to military personnel, a well-organized chemical war has been waged against this woody plant pest,” the article noted.

Other documents, including a report by an Army agronomist as well as documents related to hazardous material cleanups, point to the use of Agent Orange at the sprawling base that 1.5 million service members cycled through from 1917 to 1994.

‘The Most Toxic Chemical’

Agent Orange is a 50-50 mixture of two ingredients, known as 2,4-D and 2,4,5-T. Herbicides with the same chemical structure slightly modified were available off the shelf, sold commercially in massive amounts, and used at practically every base in the U.S., said Gerson Smoger, a lawyer who argued before the Supreme Court for Vietnam veterans to have the right to sue Agent Orange manufacturers. The combo was also used by farmers, forest workers and other civilians across the country.

The chemical 2,4,5-T contains the dioxin 2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD, a known carcinogen linked to several cancers, chronic conditions and birth defects. A recent Brown University study tied Agent Orange exposure to brain tissue damage similar to damage caused in Alzheimer’s cases. Acknowledging its harm to human health, the Environmental Protection Agency banned the use of 2,4,5-T in the U.S. in 1979. Still, the other weed killer, 2,4-D is sold off-the-shelf today.

“The bottom line is TCDD is the most toxic chemical that man has ever made,” Smoger said.

For years, the U.S. Department of Veteran Affairs has provided vets who served in Vietnam disability compensation for diseases considered to stem from exposure to Agent Orange used in military operations between 1962 and 1975.

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Decades after Osborn’s military service, the 68-year-old veteran, who never served in Vietnam, has battled one health crisis after another: a spot on his left lung and kidney, hypothyroidism and prostate cancer, an illness tied to Agent Orange exposure.

He says many of his old buddies from Fort Ord are sick as well.

“Now we have cancers that we didn’t deserve,” Osborn said.

The VA considers prostate cancer a “presumptive condition” for Agent Orange disability compensation, acknowledging that those who served in specific locations were likely exposed and that their illnesses are tied to their military service. The designation expedites affected veterans’ claims.

But when Osborn requested his benefits, he was denied. The letter said the cancer was “more likely due to your age,” not military service.

“This didn’t happen because of my age. This is happening because we were stationed in the places that were being sprayed and contaminated,” he said.

Studies show that diseases caused by environmental factors can take years to emerge. And to make things more perplexing for veterans stationed at Fort Ord, contamination from other harmful chemicals, like the industrial cleaner trichloroethylene, have been well documented on the former base, landing it on the EPA’s Superfund site list in 1990.

“We typically expect to see the effect years down the line,” said Lawrence Liu, a doctor at City of Hope Comprehensive Cancer Center who studied Agent Orange. “Carcinogens have additive effects.”

In February, the VA proposed a rule that for the first time would allow compensation to veterans for Agent Orange exposure at 17 U.S. bases in a dozen states where the herbicide was tested, used, or stored.

Fort Ord is not on that list either, because the VA’s list is based on the Defense Department’s 2019 update, which said it didn't have evidence of the herbicide being used at the California base.

“It’s a very tricky question,” Smoger said, emphasizing how widely the herbicides were used both at military bases and by civilians for similar purposes. “On one hand, we were service. We were exposed. On the other hand, why are you different from the people across the road that are privately using it?”

The VA says that it based its proposed rule on information provided by the Defense Department.

“DoD’s review found no documentation of herbicide use, testing or storage at Fort Ord. Therefore, VA does not have sufficient evidence to extend a presumption of exposure to herbicides based on service at Fort Ord at this time,” VA press secretary Terrence Hayes said in an email.

Decades of documents make case to broaden list of impacted sites

Despite the VA's response, the documentation exists, according to Elder, the environmental activist. Elder worked with toxic and remediation specialist Denise Trabbic-Pointer and former VA physician Kyle Horton to compile seven documents showing Agent Orange was, indeed, used on the grounds of Fort Ord. They include a journal article, the agronomist report and cleanup-related documents as recent as 1995 – all pointing to widespread herbicide use and experimentation along with lasting contamination at the base.

Though the documents do not call the herbicide by its colorful nickname, they routinely cite the combination of 2,4-D and 2,4,5-T. A “hazardous waste minimization assessment” dated 1991 reported 80,000 pounds of herbicides used annually at Fort Ord. It separately lists 2,4,5-T as a product for which “substitutions are necessary to minimize the environmental impacts.”

The poison oak “control program” started in 1951, according to a report by Army agronomist Floyd Otter, four years before the U.S. deepened its involvement in Vietnam. Otter detailed the use of these chemicals alone and in combination with diesel oil or other compounds at rates generally between “one to two gallons of liquid herbicide” per acre.

“In conclusion, we are fairly well satisfied with the methods,” Otter wrote, noting he was interested in “any way in which costs can be lowered or quicker kill obtained.”

An article published in California Agriculture more than a decade later includes before and after photos showing the effectiveness of chemical brush control used in a live-oak woodland at Fort Ord, again citing both chemicals in Agent Orange. The Defense Department declined to respond to recent questions about the contamination or say when the Army stopped using 2,4,5-T at Fort Ord.

“What's most compelling about Fort Ord is it was actually used for the same purpose it was used for in Vietnam – to kill plants – not just storing it,” said Julie Akey, a former Army linguist who worked at the base in the 1990s and later developed the rare blood cancer multiple myeloma.

Akey, who also worked with Elder, runs a Facebook group and keeps a list of people stationed on the base who were later diagnosed with cancer and other illnesses. So far, she has tallied more than 1,400 former Fort Ord residents who became sick.

Elder’s findings galvanized the group to speak up during a public comment period for the VA’s proposed rule. Of 546 comments, 67 came from veterans and others urging the inclusion of Fort Ord. Hundreds of others have written in regarding the use of Agent Orange and other chemicals at their bases.

While the herbicide itself sticks around for only a short time, the contaminant TCDD can linger in sediment for decades, said Kenneth Olson, a professor emeritus of soil science at the University of Illinois Urbana-Champaign.

A 1995 report from the Army’s Sacramento Corps of Engineers, which documented chemicals detected in the soil at Fort Ord, found levels of TCDD at 3.5 parts per trillion, more than double the remediation goal at the time of 1.2 ppt. Olson called the evidence convincing.

“It clearly supports the fact that 2,4,5-T with unknown amounts of dioxin TCDD was applied on the Fort Ord grounds and border fences,” Olson said. “Some military and civilian personnel would have been exposed.”

The Department of Defense has described the Agent Orange used in Vietnam as a “tactical herbicide,” more concentrated than what was commercially available in the U.S. But Olson said his research suggests that even if the grounds maintenance crew used commercial versions of 2,4,5-T available in the federal supply catalog the soldiers would have been exposed to the dioxin TCDD.

A half dozen veterans who spoke with KFF Health News said they wanted the military to take responsibility.

The Pentagon did not respond to questions regarding the upkeep of the list or the process for adding locations.

In the meantime, the Agency for Toxic Substances and Disease Registry is studying potential chemical exposure among people who worked and lived on Fort Ord between 1985 and 1994. However, the agency is evaluating drinking water for contaminants such as trichloroethylene and not contamination or pollution from other chemicals such as Agent Orange or those found in firefighting foams.

Other veterans are frustrated by the VA’s long process to recognize their illnesses and believe they were sickened by exposure at Fort Ord.

“Until Fort Ord is recognized by the VA as a presumptive site, it's probably going to be a long, difficult struggle to get some kind of compensation,” said Mike Duris, a 72-year-old veteran diagnosed with prostate cancer four years ago who ultimately underwent surgery.

Like so many others, he wonders about the connection to his training at Fort Ord in the early 70s – drinking the contaminated water and marching, crawling and digging holes in the dirt.

“Often, where there is smoke, there's fire,” Duris said.

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