Материал: Аврамова NUCLEAR ENGLISH 2013

According to estimates, 200 people died of cancer because of exposure to radiation, and thousands more suffered from related illnesses. The Mayak incident is associated with the nearby town of Kyshtym (Кыштым) because Ozyorsk did not appear on any official maps at the time.

Three Mile Island (March 28, 1979)

The worst nuclear disaster in the United States happened at the Three Mile Island nuclear plant, which is located near Harrisburg, Penn. This accident started with a plumbing breakdown. When a small valve opened to release pressure in the nuclear reactor, it malfunctioned and did not close. This led to a leakage of the cooling water and the core

started to overheat. The systems monitoring the reactor’s conditions provided incorrect information. Hence, the reactor operators shut down the emergency water which could have cooled the core.

As the core started to overheat, it gradually reached 4,300 degrees Fahrenheit and the plant had a near meltdown. But the full meltdown was prevented by the plant operators who were instructed to turn on the

supply of water. The reactor’s conditions were stabilized. According to the Nuclear Regulatory Committee, there were no deaths due to the accident, though some individuals received radiation doses of as high as 100 millirems. The Three Mile Island nuclear accident left a huge im-

pact on the American people’s attitude towards nuclear power.

Chernobyl (April 26, 1986)

The accident in Chernolyl, Ukraine, involved a reactor that on April 26, 1986, exploded after a series of mistakes by Soviet operators during an experiment at one of the facility’s four reactors. The experiment created a sudden power surge, which in turn led to a series of explosions that blew the 1,000-ton steel top off of the reactor. A cloud of radioactive material spread over the nearby town of Pripyat which was evacuated only 36 hours after the explosion. Soviet officials tried to keep the accident a secret, but on April 28 Swedish radiation monitoring stations reported radiation levels 40 percent higher than normal. The radioactive material spread as far as the UK.

In the opening days of the crisis, 32 people died at Chernobyl and dozens more suffered radiation burns. The accident caused countless birth defects and started a thyroid cancer epidemic in the region. The radiation that escaped into the atmosphere contaminated millions of acres of forest and farmland. 150,000 people had to be permanently re-

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located. In 2000, the last working reactors at Chernobyl were shut down and the plant was officially closed.

Fukushima (March 11, 2011)

An 8.9 magnitude massive earthquake and the following tsunami led to disruptions in the cooling system of the nuclear plant located along

Japan’s northeast coastline. They destroyed the electrical grid that powered the reactor, including its water-circulating system. A backup diesel generator was also destroyed. This accident triggered several explosions in the different reactors at the complex. This led to a massive evacuation in the area.

The latter three severe accidents occurred during more than 14,000 reactor-years of operation. Of all the accidents and incidents, only the Chernobyl and Fukushima resulted in significant radiation doses to the public. Other accidents were completely confined to the plant.

Radiation should be respected, not feared, experts say. Of course, there is no such thing as zero risk. But the goal for nuclear power plant operators and builders is to reduce the risk of a serious accident, like the ones at TMI and Chernobyl, to less than one in 100,000 or more years.

October 10, 1957

September 29, 1957

March 28, 1979

April 26, 1986

March 11, 2011

Exercise 2. Read about different types of reactor accidents and prepare to discuss their consequences.

A loss-of-coolant accident (LOCA) occurs if for some reason the flow of water is stopped or slowed -- for example if a pipe breaks. Then the fuel rods do not receive adequate cooling and begin to overheat.

A core meltdown is caused by an overheating of the nuclear fuel rods as a result of loss of cooling. Then the fuel rods can become so hot that they can melt. If not managed effectively, a meltdown can damage

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or destroy the reactor and release extreme levels of radiation into the environment.

The term China Syndrome describes a nuclear reactor accident characterized by a severe meltdown of the core components of the reactor, which burn through the reactor vessel and the containment building, then through the crust and body of the Earth and reach the opposite side of the Earth, which in the United States is popularly said to be China.

Reading 6-D

The "Atoms for Peace" Agency

The International Atomic Energy Agency, known as the IAEA (МАГАТЭ), is the world's center of cooperation in the nuclear field. It

was set up as the world´s "Atoms for Peace" organization in 1957 as a United Nations agency. The IAEA works for the safe, secure and peaceful uses of nuclear science and technology. The work of the IAEA covers three fields: Safety and Security (Ядерная безопасность и физи-

ческая защита ядерных объектов); Science and Technology (Ядерная наука и технология); and Safeguards and Verification (Гарантии и

контроль над ядерной деятельностью государств, не обладающих ядерным оружием). In these three areas, the Agency works to develop the use of nuclear technology for peaceful purposes, and at the same time to prevent using nuclear energy for military purposes.

The IAEA is the world's leading nuclear non-proliferation agency. The Agency plays an important role in ensuring compliance with the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) (Договор о

нераспространении ядерного оружия (ДНЯО)) of 1968.

The IAEA has its headquarters in Vienna, Austria. The agency was headed by Hans Blix of Sweden from 1981 to 1997, and by Mohammed El Baradei of Egypt from 1997 to 2009. El Baradei won the Nobel peace prize in 2005 for his work at the IAEA. Since 2009, the agency has been headed by Yukiya Amano of Japan.

Please note the difference:

Safety focuses on unintended conditions or events leading to radiological releases from authorised activities.

Security focuses on the intentional misuse of nuclear or other radioactive materials to cause harm.

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Safeguards focus on stopping activities that could lead to proliferation of nuclear weapons.

Nuclear Power Quiz

Some people think of nuclear power as a threatening menace, while others see it as a long-term source of greener electricity. What do you know about nuclear energy? Test yourself.

1.Nuclear power plants produce energy through:

A. induced fission B. induced fusion C. beta decay

2.Uranium-235 splits when _______ hits its nucleus:

A. a proton B. a neutron C. an electron

3.Uranium is a fairly common element on Earth, but it was orig-

inally formed:

A.on the moon

B.in stars

C.on asteroids

4. Fission produces lots of energy because:

A.Some of the subatomic particles disintegrate, releasing lots of energy.

B.The fission products and neutrons have more mass than the original atom.

C.The fission products and neutrons have less mass than the original

atom.

5.How many nuclear power plants are there worldwide?

A. several dozen B. several hundred C. a few thousand

6.The main difference between a nuclear plant and an oilor

coal-fired plant is:

A.the size of the generator

B.the shape of the generator

C.the fuel

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7.Where was the first nuclear reactor constructed?

A. the Gabon Republic in South Africa

B. the Department of Defense's New York facility

C. under the stands of the University of Chicago's old baseball stadium

8.To prevent overheating, control rods:

A.move extra uranium out of the way

B.absorb excess neutrons

C.create a barrier between different parts of the fuel

9. What prevents the escape of radiation in the event of an accident at a nuclear plant?

A.the containment structure

B.cooling towers

C.control rooms

10. What are some of the difficulties with nuclear power?

A.dealing with spent fuel, which is toxic

B.transporting fuel to the power plant

C.preventing nuclear accidents

D.all of the above

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