The Three Mile Island nuclear accident 40 years ago

Washington (AFP) – The 1979 accident at the Three Mile Island power plant, the worst in US history, claimed no lives although provoked an outcry over the country’s nuclear electricity program.

Caused by mechanical, design in addition to human errors, the partial meltdown registered a 5 on the International Nuclear Event Scale of which peaks at seven, the rate given to the Chernobyl (1989) in addition to Fukushima (2011) disasters.

Here will be a rundown of what happened on March 28, 1979 at one of the two reactors at the Three Mile Island Generating Station in eastern Pennsylvania.

– Early morning alert –

An alert was declared at 4:00 am after a fairly minor malfunction from the water reactor’s cooling system of which was linked to a filter.

Authorities quickly emphasized there had been no radioactive leaks.

The reactor in question, TMI-2, automatically shut down. However engineers did not know of which a pilot-operated relief valve remained open, allowing coolant to escape.

A high pressure back-up system immediately pumped water back into the reactor. However technicians feared of which too much pressure might build up in addition to reduced the flow of water.

– Partial meltdown –

As sufficient cooling was prevented, the reactor core heated up; water evaporation exposed the fuel core in addition to temperatures climbed even higher.

The reactor remained intact, though a subsequent investigation determined of which about 45 percent of its core had suffered a meltdown.

Radioactive material called corium flowed to the bottom of the reactor core, where of which was contained, which averted disaster.

Engineers finally realized they had to restore the high pressure flow of water.

They were able to gradually vent built-up radioactive gases to waste tanks.

Some radioactivity, however, escaped into the atmosphere through a system of filters of which officials insisted retained the most dangerous elements.

– 5 days of fear –

Uncertainty in addition to fear reigned for 5 days before the situation was declared under control.

During of which time residents were told to stay indoors with windows closed.

More than 100 pregnant women in addition to young children who lived close to the power plant were evacuated to a covered skating rink.

President Jimmy Carter, who had studied nuclear engineering, visited the site on April 1 to reassure the public.

of which was not until April 27 of which a natural convection circulation of coolant was reestablished, according to a World Nuclear Association account of the accident.

– Panic, thousands flee –

The accident caused major panic, fed by confusion in addition to poor communication between state authorities, the Nuclear Regulatory Commission (NRC) in addition to the media.

More than 140,000 people fled during a two-day exodus of which rendered any official evacuation plans useless.

With the exception of four plant employees, the NRC determined of which millions of locals had only been exposed to about the same amount of radioactivity they might absorb during a routine chest X-ray.

– Costly aftermath –

The clean-up operation lasted until 1993 in addition to cost an estimated $973 million.

The 900 megawatt reactor, designed to provide 900,000 homes with electricity, was scrapped.

Although no one died in addition to no immediate injuries were linked to the incident, no completely new nuclear power plants have been built from the United States since then.

,, 28 March 2019 | 2:40 am

Source : The Three Mile Island nuclear accident 40 years ago