Chernobyl Nuclear Power Plant in the Ukrainian Soviet Socialist Republic (then part of the Soviet Union, now in Ukraine).

A nuclear accident on April 26th, 1986. The result of a flawed reactor design

that was operated with poorly trained personnel.

Chernobyl had 4 nuclear reactors of the RBMK-100 design.

Before a routine shut down on April 25th, 1986 the reactor crew at Chernobyl 4 prepared for a test.

The test was to determine whether cooling of the core could continue to be ensured in the event of a loss of power.

This test was tried the previous year but it didn’t work because the power from the turbines ran down too fast.

There was not proper communication between the team in charge of the test and the personnel in charge of the safety of the nuclear reactor.

Insufficient safety precautions were included in the test and the operating personnel were not alerted to the nuclear safety implications of the electrical test and its potential danger.

The reactor began to overheat and the water coolant turned into steam.

At this point there only 6 control rods remained and the minimum safe operating number was 30.

The emergency shutdown button was pressed. With power 100 times normal the fuel pellets

began to explode cracking the fuel channels. After the explosions the reactor’s dome shaped

top blew off and the contents started to erupt out.

The many fires from this accident was the main release of radioactivity.

A total of about 1.4 x 1018 Bq (an amount = to 1,000 Hiroshima bombs) was released and over half of it was from biologically-inert noble gases.

It’s estimated that all of the xenon gas, half of the iodine and caesium, and at least 5% of the remaining radioactive material (had 192 tons of fuel) in the reactor core was released.

Scientists have estimated how much fuel was blown into the atmosphere and into the reactor but their numbers leave 10-50 tons unaccounted for

There are 3 situations raised to explain the missing fuel:The fuel was released in the explosion.It spewed out in the fire after the explosion.Its is burring deep in the rubble of the reactor.

Sweden, Denmark , Norway and Finland were detecting extremely high radiation levels and they couldn’t find where it was coming from.

They finally figured out that the radiation was carried there by the prevailing winds from the USSR.

The Soviets denied it until it was clear that something happened.

Concrete cover (sarcophagus) was built around the #4 Chernobyl reactor to keep more radiation from spreading.

It was supposedly built to last hundreds of years, but is not in good shape.

Engineering report says that it is full of holes and an earthquake of 6 or higher on the Richter scale.

It is estimated that an earthquake like that will hit the Chernobyl region once every hundred years.

Chernobyl shows just how bad the effects of a nuclear disaster are

Groundwater radiation was almost at an unsafe level all over Russia.

Many other countries were effected when clouds of radioactive smoke traveled to their country by prevailing winds and then fell and caused them radiation problems.

Deaths Only one person was killed on site and

another died in the hospital shortly after because of the injuries from the explosion.

The radiation doses from the first day caused 28 deaths.

Reports show that 60,000 people have died from diseases caused by the radiation doses they received from the Chernobyl disaster.

Health 270,000 cancers and 93,000 fatal cancer

cases caused by Chernobyl. Ongoing health impacts of Chernobyl

damaging immune and endocrine systems. leading to accelerated ageing. cardiovascular and blood illnesses.psychological illnesses. chromosomal aberrations and an increase

in fetal deformations.

Bibliography http://eightiesclub.tripod.com/id304.htm http://library.thinkquest.org/3426/data/

chernobyl-today/index.html http://chernobyl-disaster.com/ghost-town-

pripyat.php