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The Daily Need

Photo: Our own nuclear event

The cooling tower of the Three Mile Island nuclear power plant near Harrisburg, Pa., on March 30, 1979, two days after a partial core meltdown. Photo: AP/Barry Thumma

In the early morning hours of March 28, 1979, a mechanical failure at the Unit 2 reactor at Three Mile Island began a chain reaction of events that led to the worst accident in the history of U.S. nuclear power industry.

Three Mile Island Nuclear Generating Station is located on an island in the Susquehanna River, south of Harrisburg, Pa. The plant had been operating for five years, Unit 2 for only one year,  when at approximately 4 a.m., the main feed water pumps stopped running, which prevented steam generators from removing heat from the reactor. The reactor automatically shut down, but pressure in the nuclear portion of the plant began to increase. To prevent excessive pressure buildup, a pilot-operated relief valve opened, but failed to close again once the pressure decreased. Because of confusing and contradictory instruments, operators at the plant were unaware that the valve was stuck open, and as a result, radioactive cooling water drained out and caused the core of the reactor to overheat. During the early stages of the accident, the core suffered a partial meltdown as about one-half of the fuel pellets melted, but it did not breach the walls of the containment building.

Over the course of the next few days, as the incident was being investigated, there was a release of a significant amount of radioactivity from the plant’s auxiliary building. According to the American Nuclear Society, the average dose of radiation people within 10 miles of the plant received was equal to that of a chest X-ray.

As a direct result of the accident, multiple aspects of operations at U.S. nuclear power plants have been improved, including operator training, engineering, operational surveillance and emergency planning. The Unit 2 reactor was so heavily damaged that it never came back online and cleanup at the reactor continued until 1990. Unit 1 began operations again in 1985, and this year has received a license extension from the U.S. Nuclear Regulatory Commission, meaning it may continue to operate until April 19, 2034, 20 years past its original decommission date.

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  • Aptemlu

    Airplanes are safe so long as they are flying and the wings stay on.
    Cars are safe so long as they are driven carefully on an empty road.
    Ships are safe as long as the ocean is calm and weather good.
    Rifles are safe as long as they are not pointed at anyone.
    There is a message there for NUCLEAR POWER PLANTS.

  • Darlene

    Did the true numbers come out to the public of health issues for people in the area affected. Death , cancers, illnesses of any kind due to radiation , or sickness’s connected to the incident. I don’t remember ever hearing of the total, or even partial effects of this accident.

  • Eric Straatsma

    How many people truly BELIEVE that all of these accumulating hundreds of thousands of tons of nuclear spent fuel with a HALF life of 24,000 years, can truly be guarded safely without any incidents for even 1,000 years? Can anyone truly guarantee that they and their future 80,000 generations will guarantee the safety of these tombs for 24,000 years? How many generations is it for 250,000 years?

    Remember, the radiation load only reduces by 50% in the first 24,000 years. This poison must actually be guarded and kept safe for something like 250,000 years to actually make it somewhat safer, even though it would still be highly radioactive.

    I cannot even think five years into the future, much less 1,000 years. How far into the future can you think? Who will pay for this? Not the nuclear industry, that is for sure.

    What chance do we have of pulling this off AT ALL? The pyramids are only 5,000 years old, and no one can tell us how they were built, what they are REALLY for, or who built them, or why they were constructed. Has anyone taken a radiation reading inside? Maybe it was a tomb for nuclear waste….Silly point of course, but I am helping people to see, rather than stay in denial about what is happening here.

    How are we going to guard something for MUCH MUCH LONGER than the oldest pyramids, and even have a chance of passing on the knowledge of the danger to another 20,000 years worth of future generations beyond that? It is totally ridiculous.. and it is not going to happen. We do not even track what happens to the poisonous plutonium and uranium mine tailings, which are highly poisonous and radioactive. Many are being used for construction, and no one seems to care, that they are poisoning everyone who takes part.

    The danger is growing, in the form of spent fuel pools containing thousands of tons of spent fuel at each nuclear plant. Spent fuel is still dangerous, much like the Fukushima Chernobyl crisis illustrates. One spent fuel pile has gone into at least partial meltdown, despite assurances that this ‘could never happen’.. Right, just keep drinking the KoolAid.

    Want to know more?