America's most dangerous grave is buried beneath layers of lead & concrete: True story behind US's only grave that can never be exhumed

Army Specialist Richard McKinley rests in a unique grave at Arlington National Cemetery. His burial involved a double lead-lined casket and concrete enclosure. This unusual preparation was due to radioactive contamination from the 1961 SL-1 nuclear accident. The accident was the deadliest military nuclear reactor incident in United States history. This event significantly improved nuclear safety procedures and reactor design standards.

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