The Banyan--THE CLASS OF ACS-202, SPRING 2000

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	Chernobyl Revisited by The Class of ACS-202, Spring 2000
1	April 26th, 2000 marked the 14th anniversary of the Chernobyl nuclear power plant explosion. Therefore, the ASC-202 students studying nuclear fission decided it would be important to investigate the issues surrounding this disaster, why it happened and what has been learned since then. Five different groups explored the following: the political climate preceding the accident, the environmental impact on both the people and their surroundings, as well as changes made in technology and regulations that resulted from the incident.
	The Political Climate
2	The Chernobyl nuclear power facility is located in the town of Pripyat, Ukraine, which is about 75 miles north of the city of Kiev. In April of 1986 while performing a safety test, the nuclear engineers were unable to control the heat produced during the test, which resulted in a fire and explosion. Thousands of people were immediately exposed to harmful radiation, including workers, their families, and surrounding towns. The effects were felt globally and are not yet resolved.
3	In the five years prior to the Chernobyl accident the nation had experienced a rapid succession of political leaders. Beginning in 1964 Leonid Brezhnev became the head of the Soviet Union's Central Committee. He remained in power until 1982 when he was succeeded by Yuri Vladimirovich Andropov. Andropov died in February 1984 and Konstantin Chernenko became the leader until his death in March of 1985, at which time Mikhail Gorbachev took control of the Soviet Union. Thus the political climate of the time contributed to the Chernobyl tragedy through inefficient bureaucracy and secrecy.
4	To understand how an accident of this magnitude could occur it is important to examine the structure of the government that was responsible for the plant's design and implementation. At the time that Chernobyl's construction began, in the late '70s, Brezhnev had been in power for more than a decade. During the leadership of Brezhnev the Soviet Union spent billions of dollars annually involved with war efforts in Afghanistan, Cuba, Nicaragua, and Vietnam. With so much emphasis being placed on foreign affairs the funds that could have been used to purchase the proper equipment and construction materials for the Chernobyl plant were instead being spent abroad. According to Lyubov Kovalevskaya the government was building a nuclear power station with 70-90% defective materials.
5	Kovalevskaya was a journalist who lived in Pripyat and wrote for the local newspaper. She had a background in nursing, specializing in protecting people from ionizing radiation. This gave her the ability to understand the safety inefficiencies involved with the Chernobyl plant. Due to the restrictions placed on the press by the government she was not allowed to publish articles that were critical of the plant. She had the ability to gain access to restricted documents about the nuclear plant by signing a statement for a government security department, acknowledging that she had seen forbidden publications. Kovalevskaya submitted many investigative articles exposing safety hazards; however, the restrictions implemented by the government onto the press caused the newspaper editors to cut out anything critical of Chernobyl.
6	If the political climate had been more stable and operating efficiently the entire Chernobyl incident could have been avoided. It is clear from the evidence regarding the distribution of government funding and its policies of the availability of accurate and uncensored information that the politics of the day contributed to the Chernobyl disaster.
	Environmental Impact
7	The environment was extremely affected by the nuclear explosion at Chernobyl. The main factor that caused a lot of contamination and caused most of the European countries to be concerned was the plume, the cloud of smoke, and debris that traveled through Europe. The plume initially swept past Northern Poland and across the Atlantic Ocean on April 26, 1986.
8	Then the plume took an arced shape as it began to cover the country of Sweden. It had a large enough cloud from the radiation to affect the whole country. The radiation in the air was noted to be 20-150 counts per second, when the normal range is 5-10 counts per second. The longest effect the radiation had was on the reindeer and sheep in Sweden. 86,000 head of cattle were evacuated but much of the livestock was mutated. Enormous amounts of milk in Poland, Hungary, Austria, and Sweden were contaminated with radioactive iodine and radioactive cesium. There were bans on many agricultural goods in Eastern Europe because of contamination. The sale of milk, meat, many fruits and vegetables was banned in 1986 and 1987 in the Russian markets of Kiev, Chernigov, Minsk, and other small cities and towns. The cost of this ban in Russia totaled 11 billion rubles (about 400 million dollars). Even though the food was banned, there were still many health effects involved with those who consumed the contaminated food.
9	In the early phase of the Chernobyl accident, the amount of radiation from bodies of water was estimated less than 1-2 percent of the total exposure. But the radioactive contamination still made its way to many rivers in the Chernobyl area, such as the River Pripyat, Uzh River, and the Dniepr River. As the rivers drained into the Kiev, the Kanev and the Kremenchug reservoirs, the contamination of water, sediments, algae, mollusks, and fish dropped significantly by dilution. The Chernobyl Cooling Pond was the most heavily contaminated water body.
10	Within the former Soviet Union, large areas of agricultural land are still excluded from use and will continue to be unusable for many years. Any foods produced from agricultural and farm animal sources were subject to strict controls and restrictions of distribution after the accident. Most of these restrictions were removed several years ago, although, especially in some parts of Europe, the restrictions still stand. Produce from forests may continue to be a radiological protection problem for a long time because of the radioactivity grown into the trees. Contaminated fish from lakes may be a long-term problem in some countries even though drinking water is not a problem at the present time. Contamination of groundwater, especially with strontium-90, could be a problem for the future in the catchment basins downstream of the Chernobyl area.
	Radiation on the Body
11	Ionizing radiation passes through the body and interacts with tissues that then leads to cell death and later on to organ dysfunction. At low doses cell death can be accommodated by the normal mechanisms that regulate cellular regeneration. Rapid cell death begins in high doses and leads to early radiation effects that are evident within weeks, even days of exposure. They are known are "deterministic effects". These effects are usually life threatening if the doses are in high levels. Deterministic effects were responsible for a majority of the early deaths in the Chernobyl accident. Lower doses lead to cell damage from the early effects which weaken the cells and they can develop into cancerous cells that may not be evident for many years. These later effects may also cause long term hereditary defects which can be relevant throughout one's life. These effects are the "stochastic effects" and are known to be more severe than other radiation health problems.
	Immediately After the Accident
12	There were 31 deaths, which occurred immediately after and into the first week after the explosion of the Chernobyl nuclear power plant. The people that died from the disaster were exposed to 2-16 (Gy) of radiation. The US government's legal radiation exposure is 0.03 (Gy). Immediately following the explosion individuals suffered from acute radiation sickness which after 15 minutes lead to vomiting, diarrhea and fever. There were 237 people hospitalized for signs of acute radiation sickness; they were exposed to less than 2(Gy) and had skin lesions covering 50% or more of their bodies. After the fire, 135,000 people evacuated the area around the reactor, and 800,000 "liquidators" were moved in to try to decontaminate the area.
	Long Term Effects
13	A recent report shows that Chernobyl's accident is still killing people. According the Ukraine Health Ministry ten times as many people are getting thyroid cancer each year. Before 1986 only 5 individuals per year in the Ukraine were diagnosed with thyroid cancer. Ten years later it is estimated that 50-60 people per year are diagnosed and these numbers are still increasing. A study in 1996 found there were an estimated 900 cases of thyroid cancer reported, all of which were in children who were under the age of 15 during the time of diagnosis. These children were 0-5 years old during the explosion and their bodies were still forming so they were more susceptible to long term effects than any other age group.
14	An estimated 3,576 people have died from the accident. After ten years there were 2,000 extra cancer deaths per year among the workers cleaning up the Chernobyl accident. There were also 4,600 deaths among the 6.8 million residents of the contaminated territories that include Kiev, Minsk, Belarus, and many other parts of Russia.
15	Research from the first ten years after the explosion concluded that there are now more problems and effects from the Chernobyl disaster beyond our understanding. More studies should be done so more medicine can be developed that will prove effective for future treatment of victims with acute radiation sickness.
	Changes in Technology
16	It's a bit like that silly adage, "Guns don't kill people, people kill people." In this case we are talking about nuclear reactors. To date, none of the accidents at nuclear facilities were directly caused by the facilities themselves; rather they were caused by human error, usually the operators. Certainly in the case of Chernobyl, the accident would have been far less severe had the plans included a containment vessel, but again, this was human error: the desire to save time and money, to cut corners. The technology exists for safe nuclear power; unfortunately we get 'Homer Simpson' types building and running this technology.
17	Chernobyl's meltdown was caused when they decided to test the cooling systems with the primary safety measures disconnected. The Fugen reactor leak (Japan, 1999) was caused by poor waste storage practices. The Wolsung reactor leaked (South Korea, 1999) during maintenance procedures, just days after a similar disaster in Tokaimura, Japan due to the same procedure. This list could go on but we've made our point. So long as humans are in the formula, mistakes are going to be made. If we are to continue to supplement our power requirements with nuclear reactors then we had better concentrate more of our design efforts on damage control features. Features such as double back-up cooling systems and containment vessels are what kept Three-Mile Island from being our own little Chernobyl.
18	There are currently 63 nuclear plants in operation in the former Soviet Union, with more under construction. According to the International Atomic Energy Agency, the safety of these plants is a continuing concern. The current energy demand in these countries is such that there is little flexibility for closing even those plants that are the least safe, such as the dozen or so based on the flawed Chernobyl design.
19	Assistance has been started by many groups to bring the Soviet reactors up to safety standards, or at least to effect improvements. This involves modifications, identification of safety deficiencies, training of staff, and audits of the status of plant components. The United States alone has contributed 1 billion dollars for more than 700 safety related projects in the Baltic and Russian states with considerably more money earmarked for more improvements.
20	Most modifications have already been made to overcome deficiencies in all the reactors that are still operating. Automatic shutdown mechanisms now operate faster, and other safety mechanisms have been improved. A repetition of the 1986 Chernobyl accident is now virtually impossible.
21	Since 1989, over one thousand nuclear engineers from the former Soviet Union have visited western nuclear power plants so as to improve their own reactors. In 1999, an agreement was reached to close down all the substandard reactors in Bulgaria, Slovakia, and in Lithuania. The last of the four Chernobyl reactors is slated to shut down in 2001. There remain few power plants that are still of concern in the former Soviet Union
	Regulations
22	What legally has been done to insure the safety of people with regard to nuclear power plants? One of the biggest fears that most of the population shares is the possibility of a nuclear explosion and meltdown. To prevent these events from occurring the United States Nuclear Regulatory Commission (NRC) has set rules and regulations that all nuclear facilities must follow. Among the thousands of strenuous guidelines in effect for nuclear plants, these are included. Plants need to be licensed by the NRC, produce onsite and offsite emergency response plans, which include the NRC and the Federal Emergency Management Agency, (FEMA) working together, and adhere to strict building codes. Maintenance is also used as a preventative measure for safety.
23	The nuclear guides are a part of the NRC Regulatory Guides Manual, which may be found online at http://www.nrc.gov/NRC/RG/01/index.html. They are broadbased in ten different divisions, which include but are not limited to: Power Reactors, Environmental and Siting, Occupational Health and General Information. To find information regarding current draft regulatory guides, to whom the public may also make comments and suggestions you can go online at http://ruleforum.llnl.gov/cgi-bin/rulemake?source=rg.
24	In order to obtain a license to build and operate a nuclear plant both a construction permit and an operating license from the NRC must be obtained. The NRC does extensive technical reviews to ensure that construction will not jeopardize the public safety. By the granting of a license they are guaranteeing there should not be any harm or risk to national security and they will conform to the National Environmental Policy Act. To find licensing requirements that must be adhered to go to web page http://www.nrc.gov/NRC/NUREGS/SR1708/part08.html.
25	Regarding the onsite and offsite emergency response plans, federal laws require plants to have planning and preparedness ready should it be needed to protect the health and safety of the people and environment. To find more information on this subject you may find it at the FEMA fact sheet at http://www.fema.gov/home/fema/radiolo.htm.
26	Building codes are set by the NRC and are to withstand winds up to 300 miles per hour, tornadoes, and direct hits by large aircraft. The containment building is generally three-foot thick concrete lined with 3/4th inch thick steel, and all material must pass inspection. The Seabrook plants' walls are 4� foot thick concrete with steel reinforcement added and is noted as state-of-the-art with regards to its engineering along with its extra safety features. The Chernobyl plant was built using from 70% to 90% defective materials.
27	As a result of these safety measures there has never been an accident in the United States involving a commercial nuclear power plant leaking a significant amount of radioactive materials into the environment. We all can rest easy knowing that there are many scientists and nuclear engineers that are working hard to make sure that there will never be another Chernobyl.
	Nominated by Sue Eggling, Physical Science