On This Day, March 28, 1979 – Three Mile Island Reactor Nears Meltdown

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1979At 4 a.m. on March 28, 1979, the worst accident in the history of the U.S. nuclear power industry begins when a pressure valve in the Unit-2 reactor at Three Mile Island fails to close. Cooling water, contaminated with radiation, drained from the open valve into adjoining buildings, and the core began to dangerously overheat.

After the cooling water began to drain, emergency cooling pumps automatically went into operation. Left alone, these safety devices would have prevented the development of a larger crisis. However, human operators in the control room misread confusing and contradictory readings and shut off the emergency water system. The reactor was also shut down, but residual heat from the fission process was still being released. By early morning, the core had heated to over 4,000 degrees, just 1,000 degrees short of meltdown.

As the plant operators struggled to understand what had happened, the contaminated water was releasing radioactive gases throughout the plant.

Shortly after 8 a.m., word of the accident leaked to the outside world. The plant’s parent company, Metropolitan Edison, downplayed the crisis and claimed that no radiation had been detected off plant grounds, but the same day inspectors detected slightly increased levels of radiation nearby as a result of the contaminated water leak. Pennsylvania Governor Dick Thornburgh considered calling an evacuation.

Finally, at about 8 p.m., plant operators realized they needed to get water moving through the core again and restarted the pumps. The temperature began to drop, and pressure in the reactor was reduced. The reactor had come within less than an hour of a complete meltdown.


1774 – Britain passed the Coercive Act against Massachusetts.

1797 – Nathaniel Briggs patented a washing machine.

1834 – The U.S. Senate voted to censure President Andrew Jackson for the removal of federal deposits from the Bank of the United States.

1854 – The Crimean War began with Britain and France declaring war on Russia.

1865 – Outdoor advertising legislation was enacted in New York. The law banned “painting on stones, rocks and trees.”

1885 – The Salvation Army was officially organized in the U.S.

1898 – The Supreme Court ruled that a child born in the U.S. to Chinese immigrants was a U.S. citizen. This meant that they could not be deported under the Chinese Exclusion Act.

1908 – Automobile owners lobbied the U.S. Congress, supporting a bill that called for vehicle licensing and federal registration.

1910 – The first seaplane took off from water at Martinques, France. The pilot was Henri Fabre.

1917 – During World War I the Women’s Army Auxiliary Corps (WAAC) was founded.

1921U.S. President Warren Harding named William Howard Taft as chief justice of the United States Supreme Court.

1922 – Bradley A. Fiske patented a microfilm reading device.

1933 – In Germany, the Nazis ordered a ban on all Jews in businesses, professions and schools.

1939 – The Spanish Civil War ended as Madrid fell to Francisco Franco.

1945 – Germany launched the last of the V-2 rockets against England.


1958 – Eddie Cochran recorded “Summertime Blues.”


1962 – The U.S. Air Force announced research into the use of lasers to intercept missiles and satellites.

1963 – Sonny Werblin announced that the New York Titans of the American Football League was changing its name to the New York Jets.

1968 – The U.S. lost its first F-111 aircraft in Vietnam when it vanished while on a combat mission. North Vietnam claimed that they had shot it down.

1986 – More than 6,000 radio stations of all format varieties played “We are the World” simultaneously at 10:15 a.m. EST.

1990 – Jesse Owens received the Congressional Gold Medal from President George H.W. Bush.

2010 – China’s Zhejiang Geely Holding Group Co. signed a deal to buy Ford Motor Co.’s Volvo car unit.

 

Source: On-This-Day.com; History.com