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_Chernobyl _
By: Grham Prince
Disaster at Chernobyl It has been forteen years since the explosions at
Chernobyl Nuclear Power Plant in the Ukraine, Then a consitiuent republic of
the Soviet Union. The aftermath of chernobyl has been devastating; its human,
financial, and environmental cost almost beyond measure. The death toll, still
unknown, may yet reach into the thousands. Prime aqricultural land, totaling
hundreds of thousands of squaremiles, have been taken out of possibel use due
to the radioactive comtamination. Some 135,000 people were exposed to
radioactive fallout and have resetled far form contaminated areas. The
psychological impact of this uprooting will continue to hunt these people for
years. Unfortunately, cantamination levels in some regions are still high,
thus makeing further evacuations and resettlement necessary. The first serious
accident in a modern 1,000 Mwe reactor took place in the United states in
1979. The enviroment did not become con taminated due to the fact that the
reactor was contained in a hermetic, dome-shaped protective structure made of
reinforced concrete; This was not the case at Chernobyl. As Reactor four was
to be shutdown for routime maintenance on the 25 of April 1986 the technitions
decided to take advantage off down time to run a test. The test was to check
wether, in the event of a shutdown there would be enough cictrical power to
operate the emergency equipment and core cooling punmps untill the diesel
power supply came back on. As the reactor shutdown proceeded, the reactor
operated at around half power when the electric load dispatcher refused to
allow further shutdown. As part of the test the emergency core colling system
was switched off and the rector continued working at half power, At about
11:00 the grid controller agreed to further reduce the power. The test reactor
was to be stabilised at 1,000MW befor shutdown, however, due to an operatioal
mistake the power fell to about 30MW where the positive void coefficient
became a problem. The operators tried to increase the power by freeing all the
control rods manually. They eventually,afte some time, stabilised the reactor
at 200MW. Shortly afterwards an increase in coolent flow and a drop in steam
pressure occurred requiring the operatos to wihdraw almost all the rods. The
reactor became very unstable after doing this and the operators had to make
adjustments every few seconds to maintain a continuous power. At this time the
operatoors decreased the flow of feed water to maintan the steam pressure.
Also, the pumps that were powered bye the slowing turbine provided less and
less cooling to the reactor problemed reactor. The sudden increase in
temperature caused part of the fuel to repture. these fuel particles racted
with the water creating a steam explosin which destroyed the ractor core. A
second explosion added to the destruction two minutes later . The Chernobyl
Nuclear Power Station lies on the outskirts of Pripyat, southeast of the Yanov
railroad station, high on the bank of the Pripyat River, just north of its
convergence with the river Uzh. Both of these rivers flow into the Dnieper
River, which feed the Kiev reservoir to the south. The station itself is
almost 1.6 km long, form one end of ractor #1 to ractor #4. The four reactors
at Chernobyl were built in pairs, sharing buildings . The explosion blew
burning fragments of the graphite core out of the ractor building. The burnig
material fell onto the roof ofthe trubine hall and started a fire that put
reactor # 3 at risk. More that 30 seprat fires broke out. The fires were
contained by 5:00am, except for the graphite fire in the reactor core. It is
likely that most of the fire fighting had been done by local crews and the
major fires already containd before others arrived on the scene. Soviet
sources say the fires were fought by just 28 men . Chernobyl affected the
health of many people throughout Russia. Altogether the total number of
fatalities caused by Chernobyl stands at 31 officially. Around 600,000 however
were classified as being "significantly exposed" and will have their health
monitored their whole lives. Twenty-four people were disabled by the accident,
some so severely they were left as invalids for the rest of there lives.
Two-hundred thiry-eight people have suffered acute radiation syndrome. This
was updated later in 1988 at a conference in Kiev . At the conference the
estimates were updated and around 50,000 people had received 50 rad (0.5 Gy)
and about 2,000 people have received around 200 rad (2 Gy). Note that an
exposure of about 100 rad will cause symptoms of radiation sickness. The total
number of people that were in this classification is somewhere around 10,000 .
The areas of Russia that were affected most were the rural areas. This is
because 40% of the population in Western Russia is located in rural areas. The
rural areas such as Polessky outside of Ukraine were once very fertile areas
consisting of many different crops. The areas now are too contaminated to
continue such work . One problem that rural citizens faced was the new land
that they went to live on did not guarantee them a new permanent subsidized
housing when the realization came that they could not move back in
immediately. The total number of rural evacuees came to over 100,000. By
January of 1987 around 1,500 people moved back into their villages after the
military decontaminated the area . However no children were allowed to return
to the evacuated villages. The main reason for sending all of the people back
was to have them return to continue their agricultural jobs so they would not
harm the economy of the USSR too badly . There were many evacuees from
Chernobyl and the surrounding villages, the number kept changing throughout
the years and through the different resources. The main problem about
evacuating people was the elderly. They were usually persistent not to leave.
Eventually, many of the elderly returned to their abandoned homes in 1988;
their main reason was that the effects of the radiation were not as harmful to
them as to younger people . Altogether the rural effects were devastating and
the continued radiation levels still do not meet the norm. Altogether, fallout
from Chernobyl was registered in all of the Northern Hemisphere. The only
places that were affected enough to affect human health was in Europe and the
Soviet Union. The US, Canada, and Japan all set up monitoring services to
check Students and Tourists from USSR and Western and Eastern Europe. The
Chernobyl accident, combined with the effects of the Three Mile Island
incident, put an end to the development of nuclear power plants. Since 1979 no
new nuclear power plants have been built, causing the eventual diminishing of
nuclear power .
_Bibliography _
Works Cited Edel E. Robert, Chernobyl and Its Aftermath (CSIS:1994) Gould
Peter, Fire in the Rain (Johns Hopkins University Press: Baltimore, 1990)
Medvedev A. Zhores, The Legacy of Chernobyl (W.W. Norton and company: New York
1990) http://www. Chernobyl.co.uk/ March 1, 2000
Word Count: 1127
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