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Chernobyl: Ten Years After
Causes, Consequences, Solutions
3rd Version - April 1996.
Introduction.
The Chernobyl disaster has been described as `the greatest
technological catastrophe in human history'. The accident sent a
shock wave around the world, causing the cancellation of nuclear
power programmes in country after country and was a turning point
for the world nuclear industry.
Ten years later, we are beginning to see what the true impact of a
nuclear accident can be. Millions of people are still affected,
hundreds of thousands of people have still not returned to their
homes and agricultural land is still restricted hundreds of miles
from the scene of the accident.
Causes
Design Problems
The RBMK's had a number of design flaws, the main four of which
are:-
1) the sensitivity of the neutron field to reactivity
perturbations leading to control difficulties and requiring
complicated control systems.
2) No functioning containment.
3) a positive void co-efficient of reactivity that increases as
power is decreased.
4) a control rod follower design fault that actually increases
reactivity at the bottom of the core upon insertion from a
completely withdrawn position. In addition, owing to the control
rods being fitted too closely in the guide channels, their
movement was slowed by the surrounding water, giving an extremely
slow insertion time of 20 seconds. The control rod follower did
not match the full height of the reactor core, leaving a water gap
at the top and bottom and exacerbating the effect.
To date the reactors have not been made sufficiently safe and it
is impossible for them to do so. The danger was graphically
expressed by Hans Meyer, spokesman for the IAEA who told Reuters,
on the opening day of the IAEA's Conference on RBMK reactors in
Vienna on April 1st-3rd 1996 "The great danger of the RBMK
reactors is that they can catch fire in a way other reactors
cannot."
Despite this, the IAEA's Conference concluded with Viktor
Siderenko, deputy minister at the Russian Ministry of Atomic
Energy, calling for increased technical assistance for the
reactors costing between $100-150 million per reactor, compared to
the present level of about $20 million.
Consequences
It has been estimated that, although different radionuclides were
released, the total radioactivity of the material from Chernobyl
was 200 times that of the combined releases from the atomic bombs
dropped on Hiroshima and Nagasaki. However, there is still
ongoing discussion about the quantity of radioactive material
released in 1986. Many of the official estimates at the time
claimed that 50 million curies (excluding noble gases) were
released. However, in 1995, the Committee on the Safety of
Nuclear Installations from the Nuclear Energy Agency released the
results of further research on the source term which shows that,
the release was about 140 million cures, three times the original
estimate.
Contamination
In the former Soviet Union at least 9 million people have been
effected by the accident; 2.5 million in Belarus; 3.5 million in
Ukraine; and 3 million in Russia. In total over 160 000 Km2 are
contaminated in the three republics.
As far away as the United Kingdom, restrictions are still placed
on the movement and slaughter of sheep. In January 1996 these
restrictions were still in place in 219 farms effecting 317,400
sheep and covering more than 1097 km2.
Evacuation
In the three countries most affected (Belarus, Russia and
Ukraine), at least 400 000 people were forced to leave their
homes. Despite this massive evacuation there are an estimated
270 000 people still living in areas of such contamination that
strict controls are required ie. restrictions on the use of
locally grown food.
Economic
In the UK it is estimated that the total cost of compensation paid
to farmers is 12 million ($18 million). Several other European
countries suffered economic losses. In Germany, the Federal
Government paid out 452 million DM. ($307 million), while in
Austria, the government paid compensation for agricultural losses
totalling 966 million Austrian schillings ($94 million)
The Belarus Government estimate the total economic damage caused
between 1986-2015 would be (1992 June prices) $235 billion. In
Ukraine, in 1995 the Ministry for Chernobyl needed 286.4 thousand
billions of karbovanets ($2.3 billion), but received only one
third of this. It is therefore possible to estimate that the
total bill for those countries most effected will exceed $300
billion by 2015.
Health
Thyroid Cancers
It is now widely accepted that the Chernobyl accident has resulted
in a massive increase in thyroid cancers in the three countries
most affected. Already, 680 cases of thyroid cancer have been
recorded in Belarus, Russia and Ukraine. Belarus has shown a 100
fold increase, from 0.3 per million in 1981-85 to 30.6 per million
in 1991-94. Russia indicates a 10 fold increase form 0 cases in
1981-5 to 10 per million in 1991-91 and, Ukraine shows an
approximate 7 fold increase from 0.5 cases per million in 1981-85
to 3.4 per million in 1991-94.
Other Health Effects
UNICEF has assessed national statistics (ie. not just in
contaminated areas) for Belarus, between 1990-1994 and has noted
significant increases in many types of health disorders. For
example problems of the nervous and sensory organs have increased
by 43%; disorders of the digestive organs by 28%; and disorders of
bone, muscle and the connective tissue system have increased by
62%; and malignant tumours by 38%.
The Ministry of Chernobyl in Ukraine, estimates that there is a
doubling of morbidity between those living in contaminated and
clean areas.
Liquidators
Liquidators is the term given to the 800 000 workers who were
involved in putting out the fire and undertaking the immediate
recovery work. Despite the high doses that many of the
liquidators received, there has been no internationally co-
ordinated study to investigate the health consequences of the
accident.
According to the World Health Organisation, medical monitoring of
some of the liquidators is already indicating growing morbidity
and mortality rates amongst this group.
According to the Belarus Government, thyroid cancer has increased
4000%, diabetes 700%, diseases of blood organs 840% and some
malignant tubes 160% as well as a general reduction in the
functioning of the immune system.
Estimates by a major non-government organisation - the Chernobyl
Union - indicate that in the Russian Federation alone, 10% of the
liquidators are unable to maintain full-time employment, meanwhile
the Russia Ministry for Civil Defence claim that 38% of
liquidators suffer from some disease.
At their 1995 annual press conference the Ukrainian Ministry of
Health states: "According to inter-ministerial expert councils the
805 (60%) of ACCP (liquadators) deaths only in 1993 were connected
with Chernobyl NPP accident effects, and 532 (77%) - in 1994
respectively."
Sarcophagus
The Chernobyl Unit 4 post accident containment structure, more
commonly known as the "sarcophagus" was completed in November
1986. The sarcophagus was built in extremely hazardous conditions
in order to isolate and contain the remains of the damaged reactor
which contains over 400kg of plutonium and more than 100 tons of
nuclear fuel.
Designed to last 30 years, it now suffers from approximately 300
square yards of cracks and holes along with other weaknesses which
have arisen due to both the speed of construction and the
conditions under which it was built. The design of the
sarcophagus did not allow for potential earthquake stresses and
both Ukrainian and Western scientists say it could collapse in a
severe earthquake releasing radioactive dust. In March 1996, the
Ukrainian Environment Minister stated "There is a real danger that
as a result of thermal chemical migration of nuclear fuel deep in
the debris of the reactor of the fourth power unit, a critical
concentration may arise that will lead to a speedy heating and a
thermal blast", however, not all experts agree with this analysis.
Dangerous reactors still operating
Since 1986 there has not been any significant improvement in
nuclear safety in Central and Eastern Europe (CEE) or the former
Soviet Union (FSU). This is a sentiment reiterated in a
publication by the Department of Energy Office of Energy
Intelligence, which states.
"Many Soviet designed reactors operating in the successor states
to the Soviet Union pose significant safety risks because of
inherent design deficiencies, deteriorating economies, political
turmoil and weak regulatory oversight. As a class, these reactors
continue to experience serious incidents, raising the spectre of
another accident akin to Chernobyl"
The report concludes that the four worst reactors in the region
are Chernobyl (Ukraine), Kozloduy (Bulgaria), Kola (Russia) and
Iganalina (Lithuania).
The only, so called, high risk reactors (RBMK-Chernobyl type- or
VVER 440-230 models), that have been shutdown since 1986 are:
Chernobyl unit 2, which suffered a fire in 1991, but according to
plant officials will be restarted in 1996.
Medzamor (Armenia) units 1 and 2: These were shutdown in 1989
due to local opposition, but unit 2 was restarted in October 1995
and it is reported that unit 1 will be restarted in 1997.
There are a number of bi-lateral aid agreements which bring the
total assistance programme to about 1013.88 million ECU.
However, the wisdom of attempting to retrofit the reactors has
been questioned. In September 1992, the then director of Industry
and Energy Department of the World Bank Anthony Churchill stated.
"The questions we have to ask ourselves are; one, what are the
chances of these [nuclear safety] programmes being implemented
effectively within a reasonable period of time, and, two, at the
end of this process how much safety have we really bought? Are we
simply playing Russian roulette with a pistol that now has twelve
cylinders instead of six ? Is this a game we really want to play,
even with twelve cylinders?"
Solutions
In Central and Eastern Europe and the former Soviet Union there is
a huge potential for removing the need nuclear power on the short
term. However, this has not been realised partly because of
continued investment of resources into nuclear power programmes.
Instead, investment should be made into alternatives which are
more beneficial to the countries' environment and economy. In
particular investment should be focused towards.
Energy Efficiency
This is a very important untapped resource available to all
countries in the region. Conservative estimates show that at
present, electricity consumption per unit of economic output is at
least twice as high as that in OECD Europe. Moreover, since
electricity use in the region has not decreased by as much as
economic output, electricity intensity has actually increased in
recent years.
One example that highlights the benefits of energy efficiency
implementation is an analysis which was undertaken by the European
Union energy centre in Kiev. In Ukraine there are thousand of
boilers used in small scale district heating plants and power
units in small factories. The EU analysis looked at a system
using eight boilers. The test showed that the improved efficiency
gained by overhauling the eight boilers led to savings of 412,000
m3/year of natural gas, and 55,000 kWh/year of electricity. This
is just one example among tens of thousands in the region where
money and energy is being wasted.
i. Retrofitting Existing Supply Capacity
In Ukraine between 1990 and 1995 electricity production dropped by
80 Twh or approximately 35%. During this period production in the
nuclear sector remained constant, at about 70Twh. Therefore, the
decline in production took place almost exclusively in fossil fuel
plants. Since it can be assumed that the plants in operation in
1990 are still operating today, it would be possible to shut down
100% of the existing nuclear sector overnight if all existing non-
nuclear plants were utilised.
ii. Construction of New Renewable Energy Sources
This has very obvious environmental and economic advantages over
other new supply options. However, despite this little work has
been undertaken to evaluate the full range of potentials in the
region, with the exception of wind.
* The potential for Wind Power in the region is enormous. In
Ukraine, there is the potential for over 150 GW in the Sivash and
Black sea areas, in comparison Chernobyl currently has 2GW of
capacity.
* The use of small scale hydro has the potential to produce 4
times more than the present capacity of operating power plants
according to experts from the State Scientific Research, Design
Construction Institute of Unorthodox Power Generation and Electric
Engineering.
Conclusion
Despite massive international concern over nuclear safety in CEE
and the fSU and hundreds of millions of dollars in grants and
loans to the region, there has been little increase in safety and
none of the "high risk" reactors have been permanently closed.
The only conclusion that can be reached is that the money is going
to the wrong programmes. Instead of investing in energy
efficiency and alternatives, the majority of vital resources are
being paid to western consultants and contractors to review
nuclear safety.
The accident at Chernobyl has had a huge impact on the
environment especially in Belarus, Russia and Ukraine. In
addition, it has had a negative impact on the health of the
hundreds of thousands of people involved in the clean-up and those
who still live in heavily contaminated areas. Due to the long
half life of many of the radio-nuclides released a huge area will
remain contaminated for generations to come. International
organisations, such as the IAEA and WHO continue to maintain that
other than Thyroid cancers there are no negative physical health
effects from Chernobyl. However, with the exception of Thyroid
cancers no large scale international study has been completed
which investigates health effects in high risk groups e.g. the
Liquidators. Without adequate information it is impossible to
draw firm conclusion.
Due to the serious risk of a second accident at Chernobyl it is
essential that the station be closed immediately and because of
the safety problems of the existing Sarcophagus it is necessary
to take immediate action to secure it and begin preparation for
the construction of a second structure. Both of these require
urgent Western financial support to avoid another environment and
ecological disaster.
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