From 1977 to 1981, Greenpeace was part of a coalition opposed to the nuclear trigger factory between Boulder and Denver Colorado, USA. The coalition, led by the Rocky Flats Truth Force in Boulder, Colorado, established a camp on the train tracks leading to the weapons facility, blockading shipments of plutonium to the site. Photographer Rex Weyler and other Greenpeace activists were arrested along with hundreds of citizens from the region.
The plutonium trigger factory at Rocky Flats made the triggers for the entire US nuclear arsenal. A cancer spike in the region had alerted citizens to the local dangers of this facility.