Nuclear power plants are safely managed and a serious accident is extremely unlikely with modern reactor design.
Chernobyl Unit 4 exploded on April 26, 1986 - during the school year for most graduating seniors. It was the worst nuclear accident in history, releasing radioactive contamination across Europe and exposing hundreds of thousands to harmful doses.
What changed?
The 1986 graduating class was still in school when Chernobyl happened. Unit 4 of the Chernobyl Nuclear Power Plant in Soviet Ukraine exploded on April 26, 1986 at 1:23 AM local time, during what was supposed to be a routine safety test. The explosion was not a nuclear detonation, it was a steam explosion followed by a chemical fire, but it was powerful enough to blow the 1,000-ton lid off the reactor building and scatter burning graphite across the facility grounds.
Swedish radiation monitoring stations detected unusual contamination two days later, on April 28, and it was their alert, not Soviet disclosure, that forced Moscow to acknowledge that something had gone catastrophically wrong. The Soviet government had initially attempted to suppress information about the accident. Workers at the plant were told only that there had been a "mishap." Radiation levels far exceeding those from the Hiroshima bomb fallout were eventually recorded near the reactor. Approximately 350,000 people were ultimately evacuated from the surrounding region.
In American classrooms in the spring of 1986, nuclear power had been taught as a mature and safely managed technology. The previous major accident, Three Mile Island in 1979, had released minimal radiation and no one had died. Many curricula had absorbed that event as confirmation: the safety systems had worked. The lesson drawn from Three Mile Island was reassurance.
Chernobyl required a different analysis. The Soviet RBMK reactor design had a fundamental instability, at low power levels it could become more reactive as it heated, the opposite of the self-correcting behavior American reactors were designed around. This flaw was known to Soviet engineers and had not been publicly disclosed. The accident was not merely operational failure; it was a design vulnerability managed by concealment rather than correction. Students who graduated in June 1986 had spent their senior spring in a world where nuclear safety was taught as a solved problem. By graduation, it wasn't.