This video segment from Nature: “Radioactive Wolves” explores the 1986 meltdown of the Chernobyl nuclear power plant and its consequences upon the landscape, wildlife, and human population of what has come to be known as the “Exclusion Zone” surrounding the destroyed reactor.
- What is the Exclusion Zone and why was it established?
- What happened to require the political division of the Exclusion Zone?
- How does radiation released into the air by the Chernobyl accident in 1986 get into the bodies of animals today?
- What are the three fundamental questions that German scientists Barbara and Kristoff Promberger have come to the Exclusion Zone to answer? What will the answers tell them?
- How does the Pripyat River contribute to spreading the radioactive pollution of the Chernobyl disaster?
- Who were the Liquidators? Who were most of the people relocated after the Chernobyl disaster?
On April 26, 1986 an accident in one of the reactors at the Chernobyl nuclear power plant in the Soviet Union caused a meltdown. The resulting fire sent a billowing cloud of radioactive smoke over an area of 100,000 square kilometers of the Soviet Union and Eastern Europe.
The reactor fire was eventually contained by the valiant self-sacrifice of the plant’s firefighters, many of whom died shortly thereafter from acute radiation sickness. 600,000 workers, known as “liquidators,” were then brought in to clean up the contaminated site. Their main task was the construction of a containment structure—known as the “sarcophagus”—over the damaged reactor to prevent further meltdown and seal off radiation leaks. Even though they wore heavy protective gear, liquidators working in the areas of greatest radioactivity around the reactor had to be rotated out every 40 seconds. By the time the sarcophagus had been completed in December 1986, the liquidators had, on average, sustained the official lifetime limit of radiation exposure.
Chernobyl was the single greatest nuclear accident in history, releasing 400 times more radioactivity into the atmosphere than the Hiroshima bomb and tripling the world’s “background” radiation level. It is one of only two nuclear disasters classified as a “Level 7”—the highest severity—the other being the 2011 Fukushima Daiichi disaster in Japan. The Soviet Union only officially announced the disaster three days after the explosion, after scientists in Sweden noticed radiation on their shoes before entering a nuclear facility. Soviet authorities eventually evacuated approximately 400,000 people from Ukraine, Belarus, and Russia—the areas of most concentrated contamination.
Today, an area extending 19 miles in all directions from the plant is known as the “exclusion zone,” uninhabited by humans except for several hundred elderly residents of the area who have chosen to live out their lives in their contaminated homes. The area has largely reverted to its original forest and swamp environment, and many animal species are thriving in the restored habitat, but radiation levels remain so high that the workers who are in the process of building a new sarcophagus around the damaged reactor are only allowed to work five hours a day for one month before taking 15 days of rest. Ukrainian officials estimate the area will not be completely safe for human life again for another 20,000 years.
A United Nations report directly attributed 64 deaths to fallout radiation from Chernobyl, but the long-term health consequences for the millions exposed to radioactivity are difficult to ascertain. The UN estimates that upwards of 4,000 people may eventually die of disease—mostly cancer and leukemia—linked to their exposure, and other sources estimate over 200,000 premature deaths linked to the disaster.
Science in Personal and Social Perspectives – Content Standard F
As a result of activities in grades 5-8, all students should develop understanding of
- Personal health
- Natural environments may contain substances (for example, radon and lead) that are harmful to human beings. Maintaining environmental health involves establishing or monitoring quality standards related to use of soil, water, and air.
- Populations, resources, and environments
- Causes of environmental degradation and resource depletion vary from region to region and from country to country.
- Natural hazards
- Human activities also can induce hazards through resource acquisition, urban growth, land-use decisions, and waste disposal. Such activities can accelerate many natural changes.
- Risks and benefit
- Risk analysis considers the type of hazard and estimates the number of people that might be exposed and the number likely to suffer consequences. The results are used to determine the options for reducing or eliminating risks.
- Students should understand the risks associated with natural hazards (fires, floods, tornadoes, hurricanes, earthquakes, and volcanic eruptions), with chemical hazards (pollutants in air, water, soil, and food), with biological hazards (pollen, viruses, bacterial, and parasites), social hazards (occupational safety and transportation), and with personal hazards (smoking, dieting, and drinking).
As a result of activities in grades 9-12, all students should develop understanding of
- Personal and community health
- Hazards and the potential for accidents exist. Regardless of the environment, the possibility of injury, illness, disability, or death may be present. Humans have a variety of mechanisms—sensory, motor, emotional, social, and technological—that can reduce and modify hazards.
- Natural and human-induced hazards
- Human activities can enhance potential for hazards. Acquisition of resources, urban growth, and waste disposal can accelerate rates of natural change.
- Some hazards, such as earthquakes, volcanic eruptions, and severe weather, are rapid and spectacular. But there are slow and progressive changes that also result in problems for individuals and societies. For example, change in stream channel position, erosion of bridge foundations, sedimentation in lakes and harbors, coastal erosions, and continuing erosion and wasting of soil and landscapes can all negatively affect society.
- Natural and human-induced hazards present the need for humans to assess potential danger and risk. Many changes in the environment designed by humans bring benefits to society, as well as cause risks. Students should understand the costs and trade-offs of various hazards—ranging from those with minor risk to a few people to major catastrophes with major risk to many people. The scale of events and the accuracy with which scientists and engineers can (and cannot) predict events are important considerations.
- Science and technology in local, national, and global challenges
- Humans have a major effect on other species. For example, the influence of humans on other organisms occurs through land use—which decreases space available to other species—and pollution—which changes the chemical composition of air, soil, and water.