On January 21, 1968, a U. S. Air Force B-52 Stratofortress carrying four B28FI thermonuclear bombs caught fire and crashed onto the sea ice of North Star Bay near Thule Air Base, Greenland.
The high-explosive components of the weapons detonated on impact, failing to trigger a nuclear explosion but scattering pulverized plutonium, uranium, and tritium across a three-mile radius. The crash ruptured fuel tanks, igniting a jet-fuel inferno that melted the sea ice and plunged heavy radioactive wreckage beneath the black Arctic waters. The immediate imperative was Project Crested Ice, a joint American-Danish clean-up operation conducted in pitch-black polar night conditions with temperatures plunging to minus 70 degrees Fahrenheit.
Engineers raced against the impending spring melt, knowing that thawing ice would disperse radioactive particles into the marine biosphere. Clean-up crews utilized grader machinery, snowplows, and specialized vacuum trucks to scrape off the top layers of contaminated ice and snow, filling thousands of steel barrels. To contain dust and prevent wind dispersal, workers sprayed water to instantly freeze contaminated surfaces into solid blocks.
Over 6,000 tons of radioactive waste and contaminated ice were scraped up and shipped to Savannah River for permanent storage.