In 1959, a significant partial meltdown of a sodium reactor at the Santa Susana Field Lab led to a catastrophic radiation leak, which many regard as the most severe nuclear disaster in U.S. history. The gravity of the situation is heightened by its proximity, just 30 miles from Downtown Los Angeles. For two decades, this nuclear incident was kept hidden from the public, and the contamination it caused was never completely eliminated. Subsequent investigations over the years have revealed numerous disastrous accidents at the site, along with decades of mishandling radioactive materials, including the use of open-air burn pits that dispersed radioactive waste across the nearby valley. Today, SSFL is considered one of the most polluted sites globally.