Just a few years after Winston Churchill warned that “an iron curtain has descended across the continent,” launching the Cold War and igniting an arms race between East and West, the United States was quietly pushing the boundaries of nuclear technology.
The world’s eyes may have been fixed on Washington and Moscow, but a quiet, remote outpost in Idaho was about to become the site of America’s first fatal nuclear accident—a tragedy that would leave an indelible mark, all the way to the hallowed grounds of Arlington National Cemetery.
On January 3, 1961, after returning from a holiday break, three operators at the U.S. Army’s Stationary Low-Power Reactor Number One (SL-1) prepared to resume their duties.
These men—Army Specialist John Arthur Byrnes, Navy Seabee Richard Carlton Legg, and Army Specialist Four Richard McKinley—were tasked with overseeing a nuclear reactor designed to provide heat and electricity for isolated Defense Early Warning radar stations.
These radar sites played a crucial role in defending the country against the threat of Soviet bombers or intercontinental missiles, and using a nuclear reactor was considered more practical and less hazardous than constantly delivering diesel fuel.
However, this innovative effort was plagued by critical flaws.
Because there was poor oversight, insufficient training, and experimental technology that had not undergone rigorous testing, disaster was not far away.
Shortly after 9 p.m., a sudden steam explosion erupted inside the reactor.
According to Argon Electronics, a company that provides hazardous materials training, the explosion was so powerful that it lifted the entire 26,000-pound apparatus over nine feet into the air.
The blast created 500 pounds per square inch of pressure, enough to blow the plugs off the top of the reactor and launch the control rods into the ceiling “like missiles.”
“The entire reactor room was instantly filled with burning steam contaminated water and fragments of the radioactive cores,” Argon Electronics explained.
Because of the remote location and the dangers involved, it took more than ninety minutes for first responders to arrive.
When they finally entered, they found radiation levels that threatened anyone who dared step inside.
Byrnes and Legg were killed instantly in the explosion. McKinley, just 27 years old and a veteran of the Korean War, was still alive when help arrived. However, he succumbed to his injuries soon after being taken to an ambulance.
The Atomic Energy Commission quickly launched an investigation. Their findings were sobering: an operator had pulled the reactor’s central control rod too far out of its housing.
As NASA would later report, “This withdrawal caused the reactor to go ‘supercritical’ in just 4 milliseconds as the core power level surged to 20,000 megawatts or over 6,000 times the rated power output.”
Some believe the rod was stuck and had to be forcibly freed, while others say it was simply a tragic case of human error. Either way, the results were catastrophic.
Afterward, Byrnes and Legg were buried in their hometowns. McKinley’s wife, however, chose Arlington National Cemetery as his final resting place.
When his family gathered in Arlington, Virginia, just twenty-two days after the explosion, they were forced to witness the eight-minute funeral from a distance of twenty feet.
Because McKinley’s body was contaminated with radioactive isotopes, extraordinary precautions had to be taken. His remains were placed in a double lead-lined casket, lowered into a ten-foot-deep grave encased in concrete and surrounded by a metal vault, with an additional foot of concrete poured on top.
Today, Richard McKinley’s gravesite remains the only radioactive burial plot in Arlington National Cemetery.
While the site is safe to visit, the cemetery’s files contain a clear warning: “Victim of nuclear accident. Body is contaminated with long-life radioactive isotopes. Under no circumstance will the body be removed from this location without prior approval of the AEC [Atomic Energy Commission] in consultation with this headquarters.”
Because of the secrecy surrounding the Cold War, many Americans have never heard of the SL-1 tragedy. Yet, the lessons from that fateful night continue to resonate.
The courage of the men who served, and the sobering risks they faced as the United States advanced in nuclear technology, are reminders of the real cost of defending freedom during a time of immense uncertainty.
The most dangerous grave in Arlington is not only a silent witness to a tragic accident, but also a symbol of the sacrifices made in the name of progress and national security.
