The worst commercial nuclear accident to happen on American soil occurred in small-town Pennsylvania in 1979. On the International Nuclear Event Scale, TMI scores a 5. What followed was not only a massive cleanup but also massive corporate and government cover-ups with the motivation to silence those who would whistleblow against the state of nuclear regulation and industry.  

Sources:  

1.    10 Reasons to Oppose Nuclear Energy.  Green America. https://www.greenamerica.org/fight-dirty-energy/amazon-build-cleaner-cloud/10-reasons-oppose-nuclear-energy  

2.    Accidents at Nuclear Power Plants and Cancer Risk. National Cancer Institute.  https://www.cancer.gov/about-cancer/causes-prevention/risk/radiation/nuclear-accidents-fact-sheet

3.    Backgrounder on the Three Mile Island Accident. US NRC. https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/TMIle-isle.html

4.    Meltdown: Three Mile Island.  Netflix 

5.    Nuclear Power.  Wikipedia 

6.    The Nuclear Nightmare That Almost Took Out the East Coast.  New York Post.  https://nypost.com/2022/05/04/how-a-brave-engineer-saved-the-us-from-nuclear-catastrophe-new-doc/  

7.    Three Mile Island Accident. World Nuclear Association.  https://world-nuclear.org/information-library/safety-and-security/safety-of-plants/three-mile-island-accident.aspx