chernobyl nuclear power plant accident(1)

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Chernobyl Nuclear Power Plant Accident [ ] April 30, 2014 NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 1 Introduction In the early hours of 26 April 1986, one of four nuclear reactors at the Chernobyl power station exploded. The lack of information led to exaggerated claims of the number killed by the blast in the immediate area. Contamination is still a problem, however, and disputes continue about how many will eventually die as a result of the world’s worst nuclear accident. The operating crew was planning to test whether the turbines could produce sufficient energy to keep the coolant pumps running in the event of a loss of power unit the emergency diesel generator was activated. To prevent any interruptions to the power of the reactor, the safety systems were deliberately switched off. To conduct the test, the reactor had to be powered down to 25 percent of its capacity. This procedure did not go according to plan and the reactor power level fell to less than 1 percent. The power therefore had to be slowly increased. But 30 seconds after the start of the test, there was an unexpected power surge. The reactor’s emergency shutdown failed. The reactor’s fuel elements ruptured and there was a violent explosion. The 1000- tonne sealing cap on the reactor building was blown off. At temperatures of over 2000 0 C, the fuel rods melted. The graphite covering of the reactor then ignited. The graphite burned for nine days, churning huge quantities of radiation into the environment. The accident released more radiation than the deliberate dropping of a nuclear bomb on Hiroshima, Japan in August 1945.

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Chernobyl Nuclear Power Plant Accident

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Page 1: Chernobyl nuclear power plant accident(1)

Chernobyl Nuclear Power Plant Accident[ ] April 30, 2014

NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 1

Introduction

In the early hours of 26 April 1986, one of four nuclear reactors at the Chernobyl

power station exploded. The lack of information led to exaggerated claims of the

number killed by the blast in the immediate area. Contamination is still a problem,

however, and disputes continue about how many will eventually die as a result of the

world’s worst nuclear accident.

The operating crew was planning to test whether the turbines could produce sufficient

energy to keep the coolant pumps running in the event of a loss of power unit the

emergency diesel generator was activated.

To prevent any interruptions to the power of the reactor, the safety systems were

deliberately switched off. To conduct the test, the reactor had to be powered down to

25 percent of its capacity. This procedure did not go according to plan and the reactor

power level fell to less than 1 percent. The power therefore had to be slowly

increased. But 30 seconds after the start of the test, there was an unexpected power

surge. The reactor’s emergency shutdown failed.

The reactor’s fuel elements ruptured and there was a violent explosion. The 1000-

tonne sealing cap on the reactor building was blown off. At temperatures of over

20000C, the fuel rods melted. The graphite covering of the reactor then ignited. The

graphite burned for nine days, churning huge quantities of radiation into the

environment. The accident released more radiation than the deliberate dropping of a

nuclear bomb on Hiroshima, Japan in August 1945.

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 2

Chernobyl Nuclear Power Plant Accident

Background

On April 26, 1986, a sudden surge of power during a reactor systems test destroyed

Unit 4 of the nuclear power station at Chernobyl, Ukraine, in the former Soviet

Union. The accident and the fire that followed released massive amounts of

radioactive material into the environment.

Emergency crews responding to the accident used helicopters to pour sand and boron

on the reactor debris. The sand was to stop the fire and additional releases of

radioactive material; the boron was to prevent additional nuclear reactions. A few

weeks after the accident, the crews completely covered the damaged unit in a

temporary concrete structure called the “sarcophagus”, to limit further release of

radioactive material.

After the accident, officials closed off the area within 30 kilometers of the plant,

except for persons with official business at the plant and those people evaluating and

dealing with the consequences of the accident and operating the undamaged reactors.

Attempts to clean up

While trying to keep the nuclear disaster a secret, the Soviets were also trying to clean

it up. At first they poured water on the many fires then they tried to put them out with

sand and lead and then nitrogen. It took nearly two weeks to put the fires out. Citizens

in the nearby towns were told to stay indoors. Physical clean-up of the area continued.

Contaminated topsoil was placed into sealed barrels and radiated water contained.

Short term impact of Chernobyl disaster

Workers involved in the recovery and cleanup after the accident received high doses

of radiation. In most cases, these workers were not equipped with individual

dosimeters to measure the amount of radiation received. Further, domestic producers

varied, so experts could only estimate their doses.

According to Soviet estimates, between 300,000 and 600,000 people participated in

the cleanup of the 30 kilometer evacuation zone around the reactor, but many did not

enter the zone until two years after the accident.

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Chernobyl Nuclear Power Plant Accident[ ] April 30, 2014

NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 3

Chronology of the Event

1. December 2, 1984, was a routine day at the UCIL factory in Bhopal

2 MIC was stored in an underground tank. The pipeline washing started at 9:30 p.m.

as a routine maintenance operation

3. Between 10:30 - 11:00 p.m.: workers engaged in pipeline washing became aware of

a leak. Little attention was however paid considering it a normal leak. A casual

attempt was made to trace the source of leakage, but of no use. The leak continued.

4. Around 12:15 - 12:30 a.m.: The pressure in the MIC tank about upto 55 pounds per

square inch (which was the maximum the gauge could read). The temperature had

also shot up to 200 degree C and was increasing. An operator saw that the concrete

above the tank was cracking. About 12:30 a.m., the relief valve of the tank gave away

and large quantities of MIC gas leaked into the atmosphere.

6. The workers at the factory realized the risk of a massive disaster. They tried to

activate the safety systems available at the factory at about 12:30 a.m. The three

safety systems available within the factory and their condition at that time were as

under:

7. Turning on the flare tower to burn off toxic gas. This system was not in working

condition as a piece of pipeline leading to the tower had been removed for

maintenance.

8. Using the vent gas scrubber, which was considered the main line of defence. It was

also not in an operational condition.

9. Transferring the MIC from the tank into a nearby spare tank. The gauge of the

spare tank indicated that the tank already contained something. This gauge indicator

was found defective, later on.

10. After failure in all the three safety systems, the workers attempted to douse the

leaking gas with water spray. The water spray reached a height of 100 ft. from the

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 4

ground, while the leak was at 120, ft. above the ground. At 1.00 a.m., realising that

nothing could be done to stop the leak, the workers at the plant fled.

11 At about 1.00 a.m. thousands of people living around the plant were awakened by

the suffocating, burning effects of the gas. As on three sides, the UCIL plant was-

surrounded by slums and other poor settlements, the people living in these colonies

were the worst sufferers.

12. There was no warning or guidance to the general public around this time. There

were two types of alarms in the factory, one mild siren for workers and one loud

public siren. The public siren was started only at about 2:30 a.m.

13. About 2.00 a.m., a large number of people were rushing out of the town through

the highways leaving Bhopal. The mad rush on the main roads of the city resulted in

stampedes. About two lakh people had fled the city by 3:30 a.m.. The gas clouds

dissipated around 3:30 a.m..

14. By 4:00 a.m. hospitals were crowded with suffering people.

In the wake of the tragic disaster, a large number of people lost their lives and

received injuries, many to their lungs and eyes. According to the Government reports,

1754 persons had died and 200,000 were injured.

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 5

The Leakage and Its Subsequent Effects

The release

In November 1984, most of the safety systems were not functioning and many valves

and lines were in poor condition. In addition, several vent gas scrubbers had been out

of service as well as the steam boiler, intended to clean the pipes. Another issue was

that Tank 610 contained 42 tons of MIC, more than safety rules allowed for. During

the night of 2–3 December 1984, water entered a side pipe that was missing its slip-

blind plate and entered Tank E610 which contained 42 tons of MIC. A runaway

reaction started, which was accelerated by contaminants, high temperatures and other

factors. The reaction was sped up by the presence of iron from corroding non-stainless

steel pipelines. The resulting exothermic reaction increased the temperature inside the

tank to over 200 °C (392 °F) and raised the pressure. This forced the emergency

venting of pressure from the MIC holding tank, releasing a large volume of toxic

gases. About 30 metric tons of methyl isocyanate (MIC) escaped from the tank into

the atmosphere in 45 to 60 minutes.

Methylamine (1) reacts with phosgene (2) producing methyl isocyanate (3) which

reacts with 1-naphthol (4) to yield carbonyl (5)

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 6

The gas cloud

The gases were blown in southeastern direction over Bhopal.

As of 2008, UCC had not released information about the possible composition of the

cloud. Apart from MIC, the gas cloud may have contained phosgene, hydrogen

cyanide, carbon monoxide, hydrogen chloride, oxides of nitrogen, monomethyl amine

(MMA) and carbon dioxide, either produced in the storage tank or in the atmosphere.

The gas cloud was composed mainly of materials denser than the surrounding air,

stayed close to the ground and spread outwards through the surrounding community.

The nature of the cloud is still discussed. The chemical reactions would have

produced a liquid or solid aerosol with high density. The concentrations at ground

level would have been much higher than earlier published.

Acute Effects

The initial effects of exposure were coughing, severe eye irritation and a feeling of

suffocation, burning in the respiratory tract, blepharospasm, breathlessness, stomach

pains and vomiting. People awakened by these symptoms fled away from the plant.

Those who ran inhaled more than those who had a vehicle to ride. Owing to their

height, children and other people of shorter stature inhaled higher concentrations.

Many people were trampled trying to escape.

Thousands of people had died by the following morning.

Primary causes of deaths were choking, reflexogenic circulatory collapse and

pulmonary oedema. Findings during autopsies revealed changes not only in the lungs

but also cerebral oedema, tubular necrosis of the kidneys, fatty degeneration of the

liver and necrotising enteritis. The stillbirth rate increased by up to 300% and neonatal

mortality rate by around 200%.

The effects of the disaster were exacerbated by factors including the on-site storage of

dangerous chemicals in an area closely surrounded by residential slums and the fact

that the company had elected to use a more dangerous pesticide manufacturing

method than was available.

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 7

Reversible reaction of glutathione (top) with

methyl isocyanate (MIC, middle) allows the

MIC to be transported into the body

Immediate aftermath

In the immediate aftermath, the plant was closed to outsiders (including UCC) by the

Indian government, which subsequently failed to make data public, contributing to the

confusion. The initial investigation was conducted entirely by the Council of

Scientific and Industrial Research (CSIR) and the Central Bureau of Investigation.

The UCC chairman and CEO Warren Anderson, together with a technical team,

immediately traveled to India. Upon arrival, however, Anderson was placed under

house arrest and urged by the Indian government to leave the country within 24 hours.

Union Carbide organized a team of international medical experts, as well as supplies

and equipment, to work with the local Bhopal medical community, and the UCC

technical team begins assessing the cause of the gas leak.

The health care system immediately became overloaded. In the severely affected

areas, nearly 70 percent were underqualified doctors. Medical staff were unprepared

for the thousands of casualties. Doctors and hospitals were not aware about proper

treatment methods for MIC gas inhalation and they were directed to give cough

medicine and eye drops to the patients.

There were mass funerals and mass cremations. Bodies were dumped into the

Narmada River, less than 100 km from Bhopal. Within a few days, trees in the

vicinity became barren, and 2,000 bloated animal carcasses had to be disposed of.

170,000 people were treated at hospitals and temporary dispensaries. 2,000 buffalo,

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goats, and other animals were collected and buried. Supplies, including food, became

scarce owing to suppliers' safety fears. Fishing was prohibited causing further supply

shortages.

Lacking any safe alternative, on 16 December, tanks 611 and 619 were emptied of the

remaining MIC by reactivating the plant and continuing the manufacture of pesticide.

Despite safety precautions such as covering the plant in wet hessian and having water

carrying helicopters continually overflying the plant, this led to a second mass

evacuation from Bhopal. The Government of India passed the "Bhopal Gas Leak

Disaster Act" that gave the government rights to represent all victims, whether or not

in India. Complaints of lack of information or misinformation were widespread.

Formal statements were issued that air, water, vegetation and foodstuffs were safe

within the city. At the same time, people were informed that poultry was unaffected,

but were warned not to consume fish. No one under the age of 18 was registered at the

time of the accident. The number of children exposed to the gases was at least

200,000.Within weeks, the State Government established a number of hospitals,

clinics and mobile units in the gas-affected area to treat the victims.

UCC would establish a relief fund and subsequently offer interim relief to the Indian

government, who would turn it down.

Long term impact of Chernobyl disaster

Immediately following the accident, the main health concern involved radioiodine,

which has a half-life of eight days. For the longer term, there is concern about

contamination of the soil with cesium-137, which has a half-life of about 30 years.

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 9

Chernobyl Accident Effects, Facts And Figures

Children

Today in Ukraine 6,000 children are born every year with genetic heart

defects. More than 3,000 will die for lack of medical attention.

Children born since 1986 are affected by a 200 percent increase in birth

defects and a 250 percent increase in congenital birth.

85% of Belarusian children are deemed to be Chernobyl victims: they carry

“genetic markers” that could affect their health at any time and can be passed

on to the next generation.

UNICEF found increase in children’s disease rates, including 38% increase in

malignant tumours, 43% in blood circulatory illness and 63% in disorders of

the bone, muscle and connective tissue system.

More than one million children continue to live in contaminated zones.

Health

Seven million people living in the affected areas received the highest known

exposure to radiation in the history of the atomic age.

Belarusian doctors have identified increase in a number of cancers, including:

a 200% increase in breast cancer, a 100% increase in the incidence of cancer

and leukemia and a 2400% increase in the incidence of thyroid cancer.

Thyroid Cancer

A large increase in the incidence of thyroid cancer has occurred among people who

were young children and adolescents at the time of the accident and lived in the most

contaminated areas of Belarus, the Russian Federation and Ukraine. This was due to

the high levels of radioactive iodine released from the Chernobyl reactor in the early

days after the accident.

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 10

Mental health and psychological effects

The Chernobyl accident led to extensive relocation of people, loss of economic

stability, and long term threats to health in current and possibly future generations.

Widespread feelings of worry and confusion, as well as a lack of physical and

emotional well-being were commonplace.

The mortality rates among the population already outstrip their birth rates.

Environment

99% of the land of Belarus has been contaminated to varying degrees above

internationally accepted levels.

2,000 towns and villages were evacuated, and more than 400,000 people have

been relocated from their homes since 1986. Decades later, another 70,000 are

still waiting to evacuate.

The exclusion zone, known as “Death Valley”, has been increased from 30 to

70 square kilometers. No humans will ever be able to live in it again.

Economy

The cost of the Chernobyl blast and its consequences is being carried by the

survivors and will be handed down to their children for generations.

The Chernobyl disaster costs Belarus 20% of its annual national budget.

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NATIONAL INSTITUTE OF BUSINESS MANAGEMENT 11

Solutions

The Chernobyl Shelter Fund

The Chernobyl Shelter Fund was established in 1997 at the Denver 23rd G8

summit to finance the Shelter Implementation Plan (SIP). The plan calls for

transforming the site into an ecologically safe condition by means of stabilization of

the sarcophagus followed by construction of a New Safe Confinement (NSC). While

the original cost estimate for the SIP was US$768 million, the 2006 estimate was

$1.2 billion. The SIP is being managed by a consortium of Bechtel, Battelle,

and Electricité de France, and conceptual design for the NSC consists of a movable

arch, constructed away from the shelter to avoid high radiation, to be slid over the

sarcophagus. The NSC is expected to be completed in 2015, and will be the largest

movable structure ever built.

The United Nations Development Programme

The United Nations Development Programme has launched in 2003 a specific project

called the Chernobyl Recovery and Development Programme (CRDP) for the

recovery of the affected areas. The programme was initiated in February 2002 based

on the recommendations in the report on Human Consequences of the Chernobyl

Nuclear Accident. The main goal of the CRDP's activities is supporting

the Government of Ukraine in mitigating long-term social, economic, and ecological

consequences of the Chernobyl catastrophe. CRDP works in the four most Chernobyl-

affected areas in Ukraine: Kyivska, Zhytomyrska, Chernihivska and Rivnenska.

The International Project on the Health Effects of the Chernobyl Accident

The International Project on the Health Effects of the Chernobyl Accident (IPEHCA)

was created and received US $20 million, mainly from Japan, in hopes of discovering

the main cause of health problems due to 131

I radiation. These funds were divided

between Ukraine, Belarus, and Russia, the three main affected countries, for further

investigation of health effects. As there was significant corruption in former Soviet

countries, most of the foreign aid was given to Russia, and no positive outcome from

this money has been demonstrated.

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Conclusion

The tragedy of Bhopal continues to be a warning sign at once ignored and heeded.

Bhopal and its aftermath were a warning that the path to industrialization, for

developing countries in general and India in particular, is fraught with human,

environmental and economic perils. Some moves by the Indian government, including

the formation of the MoEF, have served to offer some protection of the public's health

from the harmful practices of local and multinational heavy industry and grassroots

organizations that have also played a part in opposing rampant development. The

Indian economy is growing at a tremendous rate but at significant cost in

environmental health and public safety as large and small companies throughout the

subcontinent continue to pollute. Far more remains to be done for public health in the

context of industrialization to show that the lessons of the countless thousands dead in

Bhopal have truly been heeded.