The Disaster at Three Mile Island

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In the United States and worldwide, nuclear power generates electricity distributed to millions of consumers.

This energy source is generally considered safe; however, it can be hazardous if not carefully checked.

As such, it is no surprise that fear and panic arose on the morning of March 28, 1979, when residents near the Three Mile Island nuclear facility in Pennslyvania noticed something very different about two of the plant's cooling towers.

Find out what occurred on the morning of March 8 below.

What Is Nuclear Power?

Nuclear power is used to produce electricity. Nuclear energy is formed in the nucleus, or core, of atoms.

Atoms are tiny particles that make up every object in the universe. They are the building blocks of matter. For example, your computer, desk, and chair are all made up of atoms.

This picture shows the interior of a nuclear reactor.

Where Is the Three Mile Island Nuclear Power Plant Located?

This nuclear power plant is located on Three Mile Island, near the Susquehanna River, Pennslyvania.

Nuclear power plants require lots of water to keep their reactors cool. Therefore, it is common to find most of these plants near a river or lake.

Look at the following image showing the inside of the Three Mile Island power plant in 1979.

What Occurred in March 1979?

Nuclear power plants use lots of water to prevent overheating and to ensure that the reactor (a specially designed structure used to control a nuclear reaction) operates safely and efficiently.

Plant operators must undergo intense training to operate the plant safely.

However, on the morning of March 28, 1979, a valve used to control the water flow in the reactor became stuck and was not detected by the plant's instrumentation. The plant operators did not see the problem, and the reactor continued to lose its ability to cool down.

What Happened to the Reactor?

The reactor (the structure containing the nuclear reaction) failed. As a result, the reactor had to be shut down, but not before it underwent a partial meltdown.

Meltdown is used to describe the damage that occurred to the reactor due to overheating.

What Did the Residents on Three Mile Island Observe on the Day the Accident Occurred?

The most visible sign that something was wrong was a lack of steam from the two cooling towers. In a nuclear plant, cooling towers are used as vents to release the tremendous amounts of steam generated from the water to cool the reactor.

Look at the following images. They show parts of the nuclear facility at Three Mile Island Nuclear power plant.

• What do you observe in the pictures?

Since the partial meltdown of the reactor at Three Mile Island, there has not been another nuclear disaster on American soil.

Stricter regulations and restrictions were implemented due to the incident at Three Mile Island. However, despite the new rules, there remains a certain amount of fear and uncertainty about nuclear-generated power.

This fear was further amplified by the catastrophic events that took place at the Fukushima Daiichi nuclear power plant in Japan on March 11, 2011. After a devastating earthquake, the three reactors at this plant were severely damaged, and over 100,000 people had to be evacuated from their homes.

Nevertheless, nuclear power remains a reliable energy source for the United States.

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