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Chernobyl Nuclear Accident. By: Tommy Fiocchi, Robert M. Buchsbaum III, Andrew Maximo, Alex Tittle, Brandon Wingeier, Ingrid Zibritovsky . Chernobyl Video. http://www.youtube.com/watch?v=-NlP2-Sbl9w. Background. April 26, 1986, 80 miles North of Kiev, Ukraine
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Chernobyl Nuclear Accident By: Tommy Fiocchi, Robert M. Buchsbaum III, Andrew Maximo, Alex Tittle, Brandon Wingeier, Ingrid Zibritovsky
Chernobyl Video • http://www.youtube.com/watch?v=-NlP2-Sbl9w
Background April 26, 1986, 80 miles North of Kiev, Ukraine In the new city, Pripyat (2 miles from the plant) there were 49,000 inhabitants The old town of Chernobyl (9 miles to the southeast of the complex) had a population of 12,500 Within a 18 mile radius of the power plant, the total population was between 115,000 and 135,000.
Background continued • April 25 -Prior to a routine shutdown, operators begin a test to determine how long turbines would spin and supply power to the main circulating pumps in the case that there would be a loss of main electrical power supply. • April 26- Testing continued, at one point disabling the automatic shutdown mechanisms. The reactor was in an unstable condition and as the control rods were inserted into the reactor, a power surge causing the core to overheat, ultimately resulted in the initial explosion.
Background continued • Swedish reaction • Response: a TV newscaster on Moscow television read a four-sentence statement from the Council of Ministers: ''An accident has taken place at the Chernobyl power station, and one of the reactors was damaged. Measures are being taken to eliminate the consequences of the accident. Those affected by it are being given assistance. A government commission has been set up.''
Background continued • More than 300,000 people were evacuated from a roughly 18-mile zone that would later be dubbed the “Zone of Alienation.” • 50,000 people were evacuated just from the town of Pripyat, turning it into an abandoned city virtually overnight. • 31 deaths initially (two from the explosions, one reportedly from coronary thrombosis, and 28 firemen and plant personnel from acute radiation syndrome) • However…According to the 2006 report of the UN Chernobyl Forum's 'Health' Expert Group: "The actual number of deaths caused by this accident is unlikely ever to be precisely known."
Main Steps in Creating Nuclear Power • Create heat • Create steam • Drive the turbine engine and create power
Create Heat • Heat is generated by fissioning of Uranium atoms • Must control the energy created first • Pellets, Rods, and Bundles • Fuel assembly is submerged in the nuclear core
Create Heat cont… • Uranium atoms are split by neutrons • Chain reaction occurs and heat results • Prevention of overheating • Raise and lower control rods
Create steam • Core water must be pumped into a steam generator • The heat from the core water is transferred to the turbine water • The heat produces steam
Turbine Engine and Power • Steam is piped into the turbine • Steam drives the blades of the turbine to spin • Spinning the blades generates power
Environmental and Health Impacts of the Chernobyl Nuclear Meltdown • 14x10^18 Bq of radiation released into environment. • 200,000 square-mile area contaminated. • Ukraine, Belarus, and Russia were the most affected. • Iodine-131, caesium-137, americium-241, plutonium radioisotopes, and strontium-90 were the most abundant contaminates.
Environmental and Health Impacts of the Chernobyl Nuclear Meltdown • Iodine-131 has a half-life of 8 days. • Caesium-137 has a half-life of 30 years. • The others are large particles that traveled a short distance from the blast and were able to be disposed of.
Environmental Impacts • Urban areas • Cities close to the explosion were evacuated. • Up to 400,000 evacuees. • Contamination collected in yards, on roofs, streets, in bushes, sewers, and water.
Environmental Impacts • Agricultural areas • Surface contamination affected crops and livestock. • Crops were removed, livestock were fed clean fodder, cesium binders were used to decontaminate animals who ingested caesium-137, and grazing pastures were removed and lands reseeded.
Environmental Impacts • Forests • Still has higher levels of radiation due to less human presence. • People are not to eat mushrooms and berries from the forests. • Game above a certain radiation level cannot be eaten. • Lumber above a certain radiation level cannot be harvested and burned.
Environmental Impacts • Aquatic areas • Closed water systems are still highly contaminated and it is suggested to not eat fish from these sources. • Open water systems have flushed out contaminates since the accident. • Clean drinking water was shipped in to certain cities until their drinking water radiation levels dropped.
Environmental Impacts • 600,000 emergency responders, medics, fire fighters, researchers, waste disposers, and other clean-up and response personnel were put on staff for clean-up. • They were referred to as “liquidators.”
Health Impacts • Liquidators from 1986-1989 were exposed to an average accumulated radiation dose greater than or equal to 100mSv (millisievert). • 116,000 residents in exclusionist zone in 1986 (33mSv). • 270,000 residents of strict control zones from 1986-2005 (>50mSv). • All five million residents in contaminated regions from 1986-2005 (10-20mSv).
Health Impacts • Normal radiation exposure under natural conditions is under 2.4mSv a year. • 134 liquidators were diagnosed with acute radiation syndrome. • 47 liquidators died. • 4,000 residents of Belarus who were children, at the time, were diagnosed with thyroid cancer between 1992-2002.
Federal Emergency Management Agency • Emergency response standards
International Atomic Energy Agency • Established in 1954 • Eisenhower’s “Atoms for Peace” • The 3 Pillars
Nuclear Regulatory Commission • Atomic Energy Act of 1954 • Energy Reorganization Act of 1974 • Government Oversight
Nuclear Energy Institute • The 1994 Merger • Nuclear Utility Management and Resources Council • United States Council for Energy Awareness • American Nuclear Energy Council • Edison Electric Institute’s • 1954 Atomic Industrial Forum
World Nuclear Association • Uranium Institute • Established 2001
Nuclear Operators • Leading Nuclear Operator • 20% of U.S. Nuclear Energy • Focus on safety and efficiency • U.S. Government Operated • Browns Ferry • Focus on safety and security • Safety procedures Exelon Corporation Tennessee Valley Authority
Chernobyl disaster (1986): What are the current and recent (since around 2005) events?
Health effects: • Due to release of radioactive isotopes acquired by organism (person, animal, or plant) from the environment. Released from the reactor at Chernobyl. • Differs from Hiroshima A-bomb due to lack of intense radiation burst of gamma rays. • UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) study estimated 16,000 cancer related deaths (95% confidence interval range is 7,000 to 38,000). • The most common cancer is thyroid cancer acquired in young child victims but it is also one of the least fatal cancers, only 5-10% die from it. Due to radioactive Iodine 131 isotope.
Health effects: continued • Psychological effects due to: evacuation, fear of radiation, dislocation • Increased psychological illnesses: suicide • Behavioral: increased use of cigarettes and alcohol: lung cancer, cirrhosis of liver • Dietary changes to avoid radioactive foods • Genetic effects on reproduction: • MSI (mini-satellite instability) genetic effect in males: uncertain effect • No major increases seen in major birth defects • Small scale ecological studies show no increase in leukemia, but these studies are flawed due to their small size and no large scale epidemiologic studies have been done so the incidence of leukemia due to Chernobyl is not known
II. Reports, forums and study groups recently active: • The Chernobyl Forum: 9 UN organizations and 3 nations formed a group to study Chernobyl’s effects: • IAEA (International Atomic Energy Agency) • FAO (Food and Agriculture Organization) • OCHA (UN Office for the Coordination of Humanitarian Affairs) • UNDP (UN Development Programme) • UNEP (UN Environment Programme) • UNSCEAR (UN Scientific Committee on the Effects of Atomic Radiation) • WHO (World Health Organization) • World Bank • Belarus • Russia • Ukraine
They published 3 major reports: • 2005: “Chernobyl’s legacy: Health, Environmental and Socio-Economic Impacts” • 2006: revised version of #1 • 2006: “Recommendations to the Governments of Belarus, the Russian Federation and Ukraine”
Their predictions on Chernobyl effects: • Of 600,000 “liquidators” (cleaned up the fallout), 4,000 cancer deaths • Of 6 million inhabitants, 5,000 cancer deaths and 4,000 nonlethal thyroid cancers • Relocation psychological stress: they perceive self as “victim” not “survivor” • Overly conservative behaviors in some. • Overly risky behaviors in others: ingest local foods, overuse alcohol and smoking, promiscuous sexuality
TORCH report (“The other report on Chernobyl”) by European Greens, 2006 • Main other nations exposed to Chernobyl radiation: Austria, Finland, Sweden, Moldova, Turkey, Slovenia, Switzerland, Slovak Republic, Germany, UK • More than half of those people exposed were in these outside nations • Non cancer effects included: cataracts and cardiovascular disease • Minisatellite instability (MSI) genetic defect rate is double the normal rate
II. Positive ecological effects of Chernobyl • Due to evacuation of people having a more positive effect on biodiversity bounce back than the toxic effects of the increased radiation in the exclusion zone (10 km radius from reactor #4). Return to wilderness ecosystem conditions without people around. • Moose, roe deer, Russian wild boar, river otter, fox, rabbit, rodents, wolves, eagles: 2007 Ukraine designated the exclusion zone a “wildlife sanctuary” due to its overabundance of wildlife • Background radiation was 10-100 times normal but has been decaying over the years • Supports idea that human activity is more toxic to wildlife than radiation catastrophes
Negative effects: • Elevated cancer in humans • Loss of Red Forest’s pine tree population • Speculative: buildup in radiation “genetic mutational load” that may be masked by animals outbreeding with other animals outside the exclusion zone • Decreased reproductive rate and subtle genetic defects studied in barn owls: 12% less reproduction than outside areas, defects in feathers, air sacs and beaks • Plants speculated to have adapted to higher radiation by evolving “hypermethylation” and increased DNA repair mechanisms
The “Sarcophagus” = a large concrete enclosure housing reactor #4 • The Chernobyl Shelter Fund (1997) raised 810 million euros, and the Nuclear Safety Account are two money sources managed by EBRD (European Bank for Reconstruction and Development): Goal to build a “New Safe Confinement” to shield the radioactive Sarcophagus. Original goal 2005 was delayed to 2012. • Spent fuel storage facility (ISF-2) will be built by 2013. • 2008: Ukraine began 4-stage decommissioning program to remove wastes from Chernobyl to achieve ultimately a cleared site • Lava-like fuel containing materials (“FCM”s) are lava that formed from the intense heat of the Chernobyl explosion and contain radioactivity • Collapse of the Sarcophagus: buildings recently to prevent this are: • 2006: DSSS (Designed Stabilisation Steel Structure) = a yellow steel object 207 feet tall that is next to the Sarcophagus to steady it • Upper Biological Shield = concrete slab bioshield that may collapse releasing radioactivity
Forest and grass wildfire effect: • 2010: Bryansk wildfires occurred in the contaminated areas: claim is that no effect from radioactivity released into atmosphere from burned trees and grass: Greenpeace disputes this.