Three Mile Island Historical Marker
Londonderry Township, Dauphin County, Pennsylvania
Marker Inscription
On March 28, 1979, and for several days thereafter — as a result of technical malfunctions and human error — Three Mile Island's Unit 2 Nuclear Generating Station was the scene of the nation’s worst commercial nuclear accident. Radiation was released, a p… transcription continues on the marker
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The Story
On March 28, 1979, a combination of equipment failures and confused human response sent the Unit 2 reactor at Three Mile Island into a partial core meltdown, the most serious accident in the history of American commercial nuclear power. As operators struggled to understand what their instruments were telling them, a small amount of radiation escaped and tens of thousands of nearby residents fled their homes amid days of uncertainty. Though the containment building largely held and no clear public health catastrophe followed, the frightening near-disaster on this island in the Susquehanna River became a defining moment in the nation's relationship with atomic energy.
Why it matters
Three Mile Island halted the expansion of nuclear power in the United States for a generation, reshaping public opinion, federal regulation, and the way an entire industry approached safety. It stands as a landmark in the American debate over how to weigh technological promise against its risks.
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Related events
- · Three Mile Island accident
Themes & tags
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