CHERNOBYL, UKRAINE
Potentially affected people: Initially 5.5 million, now disputed levels of effect.
Type of pollutants: Uranium, Plutonium, Radioactive Iodine, Cesium-137, Strontium, and other metals
Site description: The world's worst nuclear disaster took place on April 26, 1986, when testing in the Chernobyl power plant, 62 miles north of Kiev, triggered a fiery melt-down of the reactor's core. Thirty people were killed in the accident, 135,000 evacuated, and one hundred times more radiation than the atom bombs dropped over Hiroshima and Nagasaki was released. To this day, the 19-mile exclusion zone around the plant remains uninhabitable.
Within seven months, the reactor was buried in a concrete casing designed to absorb radiation and contain the remaining fuel. However, the sarcophagus was only meant to be a temporary solution and designed to last 20 or 30 years. A program to re-contain the site is underway.
One major reason for the concern is that though an enormous amount of radiation was released during the disaster, most of the radioactivity remained trapped within the plant itself. Some estimate that more than 100 tons of uranium and other radioactive products, such as plutonium, remain to be released if there is another accident. Chernobyl is also thought to contain some 2,000 tons of combustible materials. Leaks in the structure lead experts to fear that rainwater and fuel dust have formed a toxic liquid that may be contaminating the groundwater.
Thyroid cancer in children surrounding this area is a main health problem. Over 4000 thyroid cases had been diagnosed since 2002. Most of these cases have been attributed to elevated concentrations of radioiodine found in milk. It is hard to project lethal cancer rates and other health risks associated with this fallout. What is known is more than five million people currently inhabit the affected areas of Belarus, Russia, and Ukraine, which have all been classified as ‘contaminated’ with radionuclides due to the Chernobyl accident (above 37 kBq m-2 of 137Cs).
Furthermore, from 1992 to 2002 in Belarus, Russia and Ukraine more than 4000 cases of thyroid cancer were diagnosed among those who were children and adolescents at the time of the accident, the age group 0-14 years being most affected.
A recent WHO report has indicated that the impact on future generations from radioactivity is now quite low. However this report has been met with skepticism from local and international experts.
Cleanup Activity
Expert groups such have carried out work on health impacts, remediation effects, and socioeconomic status of the region surrounding Chernobyl. Plans for the 19-mile exclusion zone to be recovered for restricted industrial uses remain but an appropriate environmental impact assessment needs to be finished. Also, implementation of an integrated radioactive waste management program to ensure consistent management and facility capacity needs to be assessed before further development. Costs for remedial action can only be estimated, and experts have predicted these at hundreds of billions of dollars. To date, the costs of the cleanup have placed significant financial burdens on Belarus, Russian Federation, and Ukraine.
Note: Given its resounding infamy, despite the subsequent progress that has been made at this site, we felt Chernobyl must be included in this Top Ten list due to its residual environmental impact as well as its potential to further affect such an extensive region and population.
INFORMATION
IAEA International Atomic Energy Agency. “Chernobyl’s Legacy: Health, Environmental and Socio-Economic Impacts and recommendations to the governments of Belarus, the Russian Federation and Ukraine.” The Chernobyl Forum: 2003-2005.
http://www.iaea.org/Publications/Bo...l/chernobyl.pdf
IAEA International Atomic Energy Agency. “Environmental consequences of the Chernobyl accident and their remediation: Twenty Years of Experience” Report of the Chernobyl Forum Expert Group ‘Environment’. (2006)
http://www-pub.iaea.org/MTCD/public...Pub1239_web.pdf
World Health Organization. “Health Effects of the Chernobyl Accident and Special Health Care Programmes.” Report of the UN Chernobyl Forum Expert Group “Health”. (2006)
http://www.who.int/ionizing_radiati...20July%2006.pdf