Related: Environmental Issues, Math & Science

Disaster: Three Mile Island


As you might remember from our recent post about the Exxon Valdez and Deepwater Horizon oil spills, March and April have seen some of the worst man-made environmental catastrophes in history.

Today marks the 34th anniversary of another brush with disaster: the 1979 partial meltdown of the Three Mile Island Unit 2 nuclear reactor in south-central Pennsylvania.

An evacuation zone map for Three Mile Island.

A map of the evacuation zones surrounding Three Mile Island. Courtesy

The accident began at 4am when a series of equipment failures caused the reactor to overheat and much of the coolant to drain away. Without the coolant to dissipate heat, the reactor began to melt. While authorities did eventually regain control of the the situation, it came with a small cost: they still had to vent a bubble of radioactive gas into the atmosphere. Even with the meltdown contained, it took nearly a decade to assess the full extent of the damage to the reactor.

Amazingly, the accident at Three Mile Island seems to have had almost no impact on the health of people living in the area. More than 30,000 individuals were tracked; after twenty years, the study population had cancer rates comparable to those of a normal group.

More significant than the health outcomes were the ways Three Mile Island exposed the flaws in our nation’s disaster preparedness, as well as slack maintenance procedures, poor emergency planning, and disorganized communication among agencies and the media. Although it was only a partial meltdown, Three Mile Island shook the U.S. to its core and led to a range of nuclear safety reforms.

A family of skeletons watching the TV for news about Chernobyl.

A political cartoon criticizing slow and uninformative government response to Chernobyl. Residents die waiting for news. Courtesy the Library of Congress.

The anniversary of Three Mile Island falls between the dates of two other nuclear disasters: the failure and meltdown of the Fukushima I Nuclear Power Plant (March 11, 2011) and the explosion at the Chernobyl Nuclear Power Plant in Ukraine (April 26, 1986). See how commentators are comparing the three accidents and how the media has reported on them, as well.

Learn more about Three Mile Island from the Smithsonian National Museum of American History, the World Nuclear Association, and the U.S. Nuclear Regulatory Commission. Or, watch the PBS documentary, Meltdown at Three Mile Island.

You can also read up on Three Mile Island, Chernobyl, and Fukushima in resources like these:

To do your own research on nuclear energy, mix and match these search terms in our EBSCO databases:

Possible search terms relating to nuclear energy and nuclear accidents.

Nuclear energy is an important current issue. Read up, and help make the choices that will shape our future!

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