WorldWideScience

Sample records for chernobyl reactor accident

  1. Accidents - Chernobyl accident; Accidents - accident de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

  2. Chernobyl accident and its consequences

    Energy Technology Data Exchange (ETDEWEB)

    Gittus, J.H.

    1987-06-01

    The paper concerns the Chernobyl reactor accident, with emphasis on the design of the RBMK reactor and nuclear safety. A description is given of the Chernobyl nuclear power plant, including details of the RMBK reactor and safety systems. Comments on the design of the RBMK by UK experts prior to the accident are summarized, along with post-accident design changes to improve RBMK safety. Events of the Chernobyl accident are described, as well as design deficiencies highlighted by the accident. Differences between the USSR and UK approaches to nuclear safety are commented on. Finally source terms, release periods and environmental consequences are briefly discussed.

  3. Chernobyl accident and its consequences

    Energy Technology Data Exchange (ETDEWEB)

    Gittus, J.H.; Bonell, P.G.; Hicks, D.

    1987-01-01

    The USSR power reactor programme is first described. The reasons for the accident at the Chernobyl-4 RBMK nuclear reactor on 26 April 1986, the sequence of events that took place, and the immediate and long-term consequences are considered. A description of the RBMK-type reactors is given and the design changes resulting from the experience of the accident are explained. The source terms describing the details of the radioactivity release associated with the accident and the environmental consequences are covered in the last two sections of the report. Throughout the text comments referring to the UK Nuclear Installations Inspectorate Safety assessment principles have been inserted. (U.K.).

  4. Chernobyl Nuclear Reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  5. [Influence of nuclear reactor accident at Chernobyl' on the environmental radioactivity in Toyama].

    Science.gov (United States)

    Morita, M; Shoji, M; Honda, T; Sakanoue, M

    1987-06-01

    The environmental radioactivity caused by the reactor accident at Chernobyl' was investigated from May 7 to May 31 of 1986 in Toyama. Measurement of radioactivities in airborne particles, rain water, drinking water, milk, and mugwort are carried out by gamma-ray spectrometry (pure Ge detector; ORTEC GMX-23195). Ten different nuclides (103Ru, 106Ru, 131I, 132Te-I, 134Cs, 136Cs, 137Cs, 140Ba-La) are identified from samples of airborne particles. In the air samples, a maximum radioactivity concentration of each nuclide is observed on 13th May 1986. The time of the reactor shut-down and the flux of thermal neutron at the reactor were calculated from 131I/132I and 137Cs/134Cs ratio. The exposure dose in Toyama by this accident is given as follows: internal exposure; [thyroid] adult-59 microSv, child-140 microSv, baby-130 microSv, [total body] adult-0.2 microSv, child, baby-0.4 microSv, external exposure; 7 microSv, effective dose equivalent; adult-9 microSv, child-12 Sv, baby-11 microSv.

  6. Radiological consequences of the Chernobyl reactor accident; Radiologische Folgen des Tschernobyl-Ungluecks

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P.

    1996-05-01

    Large areas of Belarus, Russia, and the Ukraine have been highly contaminated by the radioactive fallout from the reactor accident at Chernobyl. The most affected areas are around Chernobyl and east of Gomel in Belarus, where part of the radioactive fallout came down with rain. The article maps the radioactive contamination through cesium 137 and iodine 131, and summarizes the immediate action taken at the time, as well as long-term remedial action for decontamination of soils. Data are given on the radiation exposure of the population, in particular doses to the thyroid, and prognoses on the incidence of thyroid cancer. (VHE) [Deutsch] Durch den Reaktorunfall von Tschernobyl wurden groessere Flaechen von Belarus, Russland und der Ukraine stark radioaktiv kontaminiert. Besonders betroffen sind die Umgebung von Tschernobyl sowie die Gegend oestlich von Gomel (Belarus), wo die radioaktive Wolke teilweise ausregnete. Der Artikel beschreibt die Belastung mit Caesium 137 und Iod 131 sowie die ergriffenen Sofortmassnahmen und die langfristigen Massnahmen zur Dekontamination der betroffenen Boeden. Die Strahlenbelastung der Bevoelkerung, v.a. die Schilddruesendosen, werden beschrieben, fuer Schilddruesenkrebs werden Prognosen gegeben. (VHE)

  7. [Chernobyl nuclear power plant accident and Tokaimura criticality accident].

    Science.gov (United States)

    Takada, Jun

    2012-03-01

    It is clear from inspection of historical incidents that the scale of disasters in a nuclear power plant accident is quite low level overwhelmingly compared with a nuclear explosion in nuclear war. Two cities of Hiroshima and Nagasaki were destroyed by nuclear blast with about 20 kt TNT equivalent and then approximately 100,000 people have died respectively. On the other hand, the number of acute death is 30 in the Chernobyl nuclear reactor accident. In this chapter, we review health hazards and doses in two historical nuclear incidents of Chernobyl and Tokaimura criticality accident and then understand the feature of the radiation accident in peaceful utilization of nuclear power.

  8. Dose estimates from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Lange, R.; Dickerson, M.H.; Gudiksen, P.H.

    1987-11-01

    The Lawrence Livermore National Laboratory Atmospheric Release Advisory Capability (ARAC) responded to the Chernobyl nuclear reactor accident in the Soviet Union by utilizing long-range atmospheric dispersion modeling to estimate the amount of radioactivity released (source term) and the radiation dose distribution due to exposure to the radioactive cloud over Europe and the Northern Hemisphere. In later assessments, after the release of data on the accident by the Soviet Union, the ARAC team used their mesoscale to regional scale model to focus in on the radiation dose distribution within the Soviet Union and the vicinity of the Chernobyl plant. 22 refs., 5 figs., 5 tabs.

  9. Workshop on short-term health effects of reactor accidents: Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    1986-08-08

    The high-dose early-effects research that has been continued has been done in the context of infrequent accidents with large radiation sources and the use of bone marrow transfusions for treating malignancies, especially leukemia. It thus seemed appropriate to bring together those who have done research on and have had experience with massive whole-body radiation. The objectives were to review what is known about the acute effects of whole-body irradiation, to review the current knowledge of therapy, and particularly of the diagnostic and immunologic problems encountered in bone marrow therapy, and to compare this knowledge with observations made to date on the Chernobyl accident radiation casualties. Dr. Robert Gale, who had helped to care for these casualties, was present at the Workshop. It was hoped that such a review would help those making continuing clinical and pathological observations on the Chernobyl casualties, and that these observations would provide a basis for recommendations for additional research that might result in improved ability to manage successfully this type of severe injury.

  10. Chernobyl lessons learned review of N Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Weber, E.T.; McNeece, J.P.; Omberg, R.P.; Stepnewski, D.D.; Lutz, R.J.; Henry, R.E.; Bonser, K.D.; Miller, N.R.

    1987-10-01

    A broad-base review of the N Reactor plant, design characteristics, administrative controls and responses unique to upset conditions has been completed. The review was keyed to Nuclear Regulatory Commission (NRC)-defined issues associated with the Chernobyl accident. Physical features of N Reactor that preclude an accident like Chernobyl include: lack of autocatalytic reactivity insertion (i.e., negative coolant void and power coefficents) and two separate, fast-acting scram systems. Administrative controls in place at N Reactor would effectively protect against the operator errors and safety violations that set up the Chernobyl accident. Several items were identified where further near-term action is appropriate to ensure effectiveness of existing safety features: Resolve a question concerning the exact point at which Emergency Core Cooling System (ECCS) activation by manual actions should be implemented or deferred if automatic ECCS trip fails. Ensure appropriate revision of the Emergency Response Guides and full communication of the correct procedure to all Operations, Safety and cognizant Technology staff. Train reactor operators in the currently recognized significance of the Graphite and Shield Cooling System (GSCS) in severe accident situations and cover this appropriately in the Emergency Response Guides. Complete reviews which establish an independent verification that pressure tube rupture will not propagate to other tubes. 15 refs., 3 tabs.

  11. MLAM assessment of air concentration, deposition, and dose for Chernobyl reactor accident

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, A.R.; Davis, W.E.; Didier, B.T.; Soldat, J.K.; Napier, B.A.; Peloquin, R.A.

    1989-12-01

    The purpose of this report is to provide estimates for the areas in Europe affected by the accident involving Unit 4 of the Chernobylskaya Atomic Energy Station which resulted in the release of radioactive material to the atmosphere.

  12. Medical consequences of Chernobyl accident

    Directory of Open Access Journals (Sweden)

    Galstyan I.A.

    2015-12-01

    Full Text Available Aim: to study the long-term effects of acute radiation syndrome (ARS, developed at the victims of the Chernobyl accident. Material and Methods. 237 people were exposed during the accident, 134 of them were diagnosed with ARS. Dynamic observation implies a thorough annual examination in a hospital. Results. In the first 1.5-2 years after the ARS mean group indices of peripheral blood have returned to normal. However, many patients had transient expressed moderate cytopenias. Granulocytopenia, thrombocytopenia, lymphopenia and erythropenia were the most frequently observed things during the first 5 years after the accident. After 5 years their occurences lowered. In 11 patients the radiation cataract was detected. A threshold dose for its development is a dose of 3.2 Gy Long-term effects of local radiation lesions (LRL range from mild skin figure smoothing to a distinct fibrous scarring, contractures, persistently recurrent late radiation ulcers. During all years of observation we found 8 solid tumors, including 2 thyroid cancers. 5 hematologic diseases were found. During 29 years 26 ARS survivors died of various causes. Conclusion. The health of ones with long-term ARS effects is determined by the evolution of the LRL effects on skin, radiation cataracts, hema-tological diseases and the accession of of various somatic diseases, not caused by radiation.

  13. US Department of Energy Chernobyl accident bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, R A; Mahaffey, J A; Carr, F Jr

    1992-04-01

    This bibliography has been prepared by Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) Office of Health and Environmental Research to provide bibliographic information in a usable format for research studies relating to the Chernobyl nuclear accident that occurred in the Ukrainian Republic, USSR in 1986. This report is a product of the Chernobyl Database Management project. The purpose of this project is to produce and maintain an information system that is the official United States repository for information related to the accident. Two related products prepared for this project are the Chernobyl Bibliographic Search System (ChernoLit{trademark}) and the Chernobyl Radiological Measurements Information System (ChernoDat). This report supersedes the original release of Chernobyl Bibliography (Carr and Mahaffey, 1989). The original report included about 2200 references. Over 4500 references and an index of authors and editors are included in this report.

  14. [The radioecology of the grapevine. 2. Effects of the nuclear reactor accident in Chernobyl on the radioactivity in the soil, leaves, grapes and wine].

    Science.gov (United States)

    Wagner, A; Diehl, J F

    1991-04-01

    Natural (tritium, 14C, 40K, 226Ra) and man-made radionuclides (90Sr, 134Cs, 137Cs) were determined in soil (top 30 cm), vine leaves, grapes and wine in eight locations of the most important viticultural regions in the Federal Republic of Germany. The results obtained in 1983-1985 have been published previously. Part II of this study presents results obtained in 1986 and 1987, i.e. after the reactor accident at Chernobyl in the Soviet Union. The mean content of 137Cs before (after) Chernobyl was 4 (9) Bq/kg dry matter in soil, 0.07 (3) Bq/kg fresh matter in leaves, 0.02 (0.4) Bq/kg in grapes, and 0.008 (0.9) Bq/L in wine. As compared with 1986, distinctly lower levels were found in leaves, grapes and wine in 1987. In 1986 the content of 134Cs was about half that of 137Cs. Owing to its shorter half-life, 134Cs was below the detection limit in many of the 1987 samples. Transfer factors such as from soil to leaves and from soil to grapes for caesium agreed well in 1983-1985 and 1987, but showed considerable deviations in 1986, due to the ubiquitous contamination of the environment. Results of 90Sr determinations confirmed other reports showing this radionuclide to be a very minor contributor to the total radioactivity released at Chernobyl. No effect of the reactor accident on levels of the other radionuclides was detected.

  15. Impact of {sup 134}Cs and {sup 137}Cs from the Chernobyl reactor accident on the Spanish Mediterranean marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Molero, J.; Sanchez-Cabeza, J.A.; Merino, J. [Grup de Fisica de les Radiacions, Departament de Fisica, Facultat de Ciencies, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Mitchell, P.I. [Laboratory of Radiation Physics, University College, Dublin (Ireland); Vidal-Quadras, A. [Grup de Fisica de les Radiacions, Departament de Fisica, Facultat de Ciencies, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain)

    1999-05-01

    As part of a study aiming to establish the distribution and bioavailability of man-made radionuclides in the marine environment, radiocaesium levels were determined in large volume sea water samples and in the sea-grass Posidonia oceanica collected along the Spanish Mediterranean coast. Results obtained from 1987 to 1991 showed the enhancement of radiocaesium levels in the Spanish Mediterranean marine environment after the Chernobyl accident. The well-known {sup 134}Cs/{sup 137}Cs isotopic ratio in Chernobyl fresh deposition was used to identify the weapon tests fall-out and Chernobyl deposition components. {sup 137}Cs and {sup 134}Cs mean concentrations in surface waters from the Spanish Mediterranean shoreline were 4.8{+-}0.2 and 0.27{+-}0.01 Bq m{sup -3}, respectively. {sup 137}Cs concentration incorporated into Mediterranean waters as a consequence of the post-Chernobyl deposition was estimated to be 1.16{+-}0.04 Bq m{sup -3}, which is a 33{+-}2% increase over the previous levels. {sup 137}Cs estimated inventory in the surface water layer (0-50 m) of the Catalan-Balearic basin was 17.4{+-}0.5 TBq for {sup 137}Cs, of which 4.3{+-}0.2 TBq must be attributed to post-Chernobyl deposition, and 1.00{+-}0.04 TBq for {sup 134}Cs. Activation and fission products such as {sup 106}Ru, {sup 110m}Ag, {sup 134}Cs, {sup 137}Cs and {sup 144}Ce, were detected in all samples of Posidonia oceanica. Mean radiocaesium levels in the bioindicator were 1.02{+-}0.25 and 0.20{+-}0.03 Bq kg{sup -1} for {sup 137}Cs and {sup 134}Cs, respectively, corresponding to a mean isotopic ratio {sup 134}Cs/{sup 137}Cs equal to 0.20{+-}0.04 (1987). {sup 137}Cs activity incorporated by Posidonia oceanica after the Chernobyl deposition over the Mediterranean Sea was estimated as 0.51{+-}0.08 Bq kg{sup -1}. Therefore, {sup 137}Cs specific activity had increased 100{+-}40% one year after the accident. Low level radioactive liquid effluents from the nuclear power plants located on the southern Catalan

  16. First international workshop on severe accidents and their consequences. [Chernobyl Accident

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    An international workshop on past severe nuclear accidents and their consequences was held in Dagomys region of Sochi, USSR on October 30--November 3, 1989. The plan of this meeting was approved by the USSR Academy of Sciences and by the USSR State Committee of the Utilization of Atomic Energy. The meeting was held under the umbrella of the ANS-SNS agreement of cooperation. Topics covered include analysis of the Chernobyl accident, safety measures for RBMK type reactors and consequences of the Chernobyl accident including analysis of the ecological, genetic and psycho-social factors. Separate reports are processed separately for the data bases. (CBS)

  17. The Chernobyl Nuclear Power Plant accident: ecotoxicological update

    Science.gov (United States)

    Eisler, R.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John=

    2003-01-01

    The accident at the Chernobyl, Ukraine, nuclear reactor on 26 April 1986 released large amounts of radiocesium and other radionuclides into the environment, contaminating much of the northern hemisphere, especially Europe. In the vicinity of Chernobyl, at least 30 people died, more than 115,000 others were evacuated, and consumption of milk and other foods was banned because of radiocontamination. At least 14,000 human cancer deaths are expected in Russia, Belarus, and the Ukraine as a direct result of Chernobyl. The most sensitive local ecosystems, as judged by survival, were the soil fauna, pine forest communities, and certain populations of rodents. Elsewhere, fallout from Chernobyl significantly contaminated freshwater and terrestrial ecosystems and flesh and milk of domestic livestock; in many cases, radionuclide concentrations in biological samples exceeded current radiation protection guidelines. Reindeer (Rangifer tarandus) in Scandinavia were among the most seriously afflicted by Chernobyl fallout, probably because their main food during winter (lichens) is an efficient absorber of airborne particles containing radiocesium. Some reindeer calves contaminated with 137Cs from Chernobyl showed 137Cs-dependent decreases in survival and increases in frequency of chromosomal aberrations. Although radiation levels in the biosphere are declining with time, latent effects of initial exposure--including an increased frequency of thyroid and other cancers--are now measurable. The full effect of the Chernobyl nuclear reactor accident on natural resources will probably not be known for at least several decades because of gaps in data on long-term genetic and reproductive effects and on radiocesium cycling and toxicokinetics.

  18. Congenital malformations and infant mortality from the Chernobyl reactor accident; Angeborene Fehlbildungen und Saeuglingssterblichkeit nach dem Reaktorunfall in Tschernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Schoetzau, A.; Santen, F. van; Irl, C.; Grosche, B.

    1994-12-01

    The health impact of radiological contamination in Bavaria from the Chernobyl accident was evaluated. According to caesium 137 levels in soil samples, Bavaria was subdivided in a higher contaminated region (Southern Bavaria) and a lower contaminated region (Northern Bavaria). Indicators for health effects were congenital malformations, perinatal mortality, and infant mortality. Definition of the study periods accounted for the temporal relationship between conception as well as organogenesis and the time of highest exposure to radioactivity during the first weeks of May 1986. Statistical analysis was based on a combined spatial and temporal comparison. The results of the study do not show a significant increase in any of the outcome variables. Consequently, this study provides no evidence that radiation from Chernobyl caused a rise in the birth prevalence of congenital malformations or perinatal and infant mortality in the Bavarian population. (orig.) [Deutsch] Der vorliegende Bericht beschaeftigt sich mit den Folgen der Strahlenexposition in Bayern nach dem Reaktorunfall in Tschernobyl. Es wurde der Frage nachgegangen, ob eine Zunahme negativer gesundheitlicher Wirkungen in hoeher exponierten Bevoelkerungsgruppen im Vergleich zu niedriger exponierten feststellbar war. Der Expositionsstatus wurde nach der Bodenkontamination des Wohnortes bestimmt. Entsprechend der unterschiedlichen Hoehe des Radiocaesium-Gehaltes in Bodenproben wurde die Bevoelkerung der drei suedlichen bayerischen Regierungsbezirke `Oberbayern`, `Niederbayern` und `Schwaben` (Suedbayern) als hoeher und die Bevoelkerung der vier noerdlichen Regierungsbezirke `Oberpfalz`, `Oberfanken`, `Mittelfranken` und `Unterfranken` (Nordbayern) als niedriger exponiert definiert. Als Indikatoren fuer gesundheitliche Wirkungen wurden Veraenderungen der Geburtspraevalenz von Kindern mit ausgewaehlten angeborenen Fehlbildungen sowie Veraenderungen in den Raten der perinatalen Mortalitaet und der Gesamtsterblichkeit

  19. Chernobyl accident. [Radiation monitoring in UK

    Energy Technology Data Exchange (ETDEWEB)

    Gittus, J.H.

    1986-07-01

    A brief report is given of the implications for the UK from the radioactivity released during the Chernobyl accident. Results of radio-activity monitoring around the UK are given and the additional radiation doses to the UK population are evaluated.

  20. Consequences and countermeasures in a nuclear power accident: Chernobyl experience.

    Science.gov (United States)

    Kirichenko, Vladimir A; Kirichenko, Alexander V; Werts, Day E

    2012-09-01

    Despite the tragic accidents in Fukushima and Chernobyl, the nuclear power industry will continue to contribute to the production of electric energy worldwide until there are efficient and sustainable alternative sources of energy. The Chernobyl nuclear accident, which occurred 26 years ago in the former Soviet Union, released an immense amount of radioactivity over vast territories of Belarus, Ukraine, and the Russian Federation, extending into northern Europe, and became the most severe accident in the history of the nuclear industry. This disaster was a result of numerous factors including inadequate nuclear power plant design, human errors, and violation of safety measures. The lessons learned from nuclear accidents will continue to strengthen the safety design of new reactor installations, but with more than 400 active nuclear power stations worldwide and 104 reactors in the Unites States, it is essential to reassess fundamental issues related to the Chernobyl experience as it continues to evolve. This article summarizes early and late events of the incident, the impact on thyroid health, and attempts to reduce agricultural radioactive contamination.

  1. Preliminary dose assessment of the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Hull, A.P.

    1987-01-01

    From the major accident at Unit 4 of the Chernobyl nuclear power station, a plume of airborne radioactive fission products was initially carried northwesterly toward Poland, thence toward Scandinavia and into Central Europe. Reports of the levels of radioactivity in a variety of media and of external radiation levels were collected in the Department of Energy's Emergency Operations Center and compiled into a data bank. Portions of these and other data which were obtained directly from published and official reports were utilized to make a preliminary assessment of the extent and magnitude of the external dose to individuals downwind from Chernobyl. Radioactive /sup 131/I was the predominant fission product. The time of arrival of the plume and the maximum concentrations of /sup 131/I in air, vegetation and milk and the maximum reported depositions and external radiation levels have been tabulated country by country. A large amount of the total activity in the release was apparently carried to a significant elevation. The data suggest that in areas where rainfall occurred, deposition levels were from ten to one-hundred times those observed in nearby ''dry'' locations. Sufficient spectral data were obtained to establish average release fractions and to establish a reference spectra of the other nuclides in the release. Preliminary calculations indicated that the collective dose equivalent to the population in Scandinavia and Central Europe during the first year after the Chernobyl accident would be about 8 x 10/sup 6/ person-rem. From the Soviet report, it appears that a first year population dose of about 2 x 10/sup 7/ person-rem (2 x 10/sup 5/ Sv) will be received by the population who were downwind of Chernobyl within the U.S.S.R. during the accident and its subsequent releases over the following week. 32 refs., 14 figs., 20 tabs.

  2. Comparison of the accident process, radioactivity release and ground contamination between Chernobyl and Fukushima-1.

    Science.gov (United States)

    Imanaka, Tetsuji; Hayashi, Gohei; Endo, Satoru

    2015-12-01

    In this report, we have reviewed the basic features of the accident processes and radioactivity releases that occurred in the Chernobyl accident (1986) and in the Fukushima-1 accident (2011). The Chernobyl accident was a power-surge accident that was caused by a failure of control of a fission chain reaction, which instantaneously destroyed the reactor and building, whereas the Fukushima-1 accident was a loss-of-coolant accident in which the reactor cores of three units were melted by decay heat after losing the electricity supply. Although the quantity of radioactive noble gases released from Fukushima-1 exceeded the amount released from Chernobyl, the size of land area severely contaminated by (137)Cesium ((137)Cs) was 10 times smaller around Fukushima-1 compared with around Chernobyl. The differences in the accident process are reflected in the composition of the discharged radioactivity as well as in the composition of the ground contamination. Volatile radionuclides (such as (132)Te-(132)I, (131)I, (134)Cs and (137)Cs) contributed to the gamma-ray exposure from the ground contamination around Fukishima-1, whereas a greater variety of radionuclides contributed significantly around Chernobyl. When radioactivity deposition occurred, the radiation exposure rate near Chernobyl is estimated to have been 770 μGy h(-1) per initial (137)Cs deposition of 1000 kBq m(-2), whereas it was 100 μGy h(-1) around Fukushima-1. Estimates of the cumulative exposure for 30 years are 970 and 570 mGy per initial deposition of 1000 kBq m(-2) for Chernobyl and Fukusima-1, respectively. Of these exposures, 49 and 98% were contributed by radiocesiums ((134)Cs + (137)Cs) around Chernobyl and Fukushima-1, respectively.

  3. Comparison of the accident process, radioactivity release and ground contamination between Chernobyl and Fukushima-1

    Science.gov (United States)

    Imanaka, Tetsuji; Hayashi, Gohei; Endo, Satoru

    2015-01-01

    In this report, we have reviewed the basic features of the accident processes and radioactivity releases that occurred in the Chernobyl accident (1986) and in the Fukushima-1 accident (2011). The Chernobyl accident was a power-surge accident that was caused by a failure of control of a fission chain reaction, which instantaneously destroyed the reactor and building, whereas the Fukushima-1 accident was a loss-of-coolant accident in which the reactor cores of three units were melted by decay heat after losing the electricity supply. Although the quantity of radioactive noble gases released from Fukushima-1 exceeded the amount released from Chernobyl, the size of land area severely contaminated by 137Cesium (137Cs) was 10 times smaller around Fukushima-1 compared with around Chernobyl. The differences in the accident process are reflected in the composition of the discharged radioactivity as well as in the composition of the ground contamination. Volatile radionuclides (such as 132Te-132I, 131I, 134Cs and 137Cs) contributed to the gamma-ray exposure from the ground contamination around Fukishima-1, whereas a greater variety of radionuclides contributed significantly around Chernobyl. When radioactivity deposition occurred, the radiation exposure rate near Chernobyl is estimated to have been 770 μGy h−1 per initial 137Cs deposition of 1000 kBq m−2, whereas it was 100 μGy h−1 around Fukushima-1. Estimates of the cumulative exposure for 30 years are 970 and 570 mGy per initial deposition of 1000 kBq m−2 for Chernobyl and Fukusima-1, respectively. Of these exposures, 49 and 98% were contributed by radiocesiums (134Cs + 137Cs) around Chernobyl and Fukushima-1, respectively. PMID:26568603

  4. [Morphological verification problems of Chernobyl factor influence on the prostate of coalminers of Donbas--liquidators of Chernobyl accident].

    Science.gov (United States)

    Danylov, Iu V; Motkov, K V; Shevchenko, T I

    2013-12-01

    Problem of a diagnostic of Chernobyl factor influences on different organs and systems of Chernobyl accident liquidators are remain actually until now. Though morbidly background which development at unfavorable work conditions in underground coalminers prevents from objective identification features of Chernobyl factor influences. The qualitative and quantitative histological and immunohistochemical law of morphogenesis changes in prostate of Donbas's coalminer-non-liquidators Chernobyl accident in comparison with the group of Donbas's coalminers-liquidators Chernobyl accident which we were stationed non determined problem. This reason stipulates to development and practical use of mathematical model of morphogenesis of a prostatic gland changes.

  5. [Morphological verification problems of Chernobyl factor influence on the testis of coal miners of Donbas-liquidators of Chernobyl accident].

    Science.gov (United States)

    Danylov, Iu V; Motkov, K V; Shevchenko, T I

    2013-01-01

    Problem of a diagnostic of Chernobyl factor influences on different organs and systems of Chernobyl accident liquidators are remain actually until now. Though morbidly background which development at unfavorable work conditions in underground coalminers prevents from objective identification features of Chernobyl factor influences. The qualitative and quantitative histological and immunohistochemical law of morphogenesis changes in testis of Donbas's coalminer - non-liquidators Chernobyl accident in comparison with the group of Donbas's coalminers-liquidators Chernobyl accident, which we were stationed non determined problem. This reason stipulates to development and practical use of mathematical model of morphogenesis of a testis changes.

  6. Radioactive waste management in the Chernobyl exclusion zone: 25 years since the Chernobyl nuclear power plant accident.

    Science.gov (United States)

    Oskolkov, Boris Y; Bondarkov, Mikhail D; Zinkevich, Lubov I; Proskura, Nikolai I; Farfán, Eduardo B; Jannik, G Timothy

    2011-10-01

    Radioactive waste management is an important component of the Chernobyl Nuclear Power Plant accident mitigation and remediation activities in the so-called Chernobyl Exclusion Zone. This article describes the localization and characteristics of the radioactive waste present in the Chernobyl Exclusion Zone and summarizes the pathways and strategy for handling the radioactive waste-related problems in Ukraine and the Chernobyl Exclusion Zone and, in particular, the pathways and strategies stipulated by the National Radioactive Waste Management Program.

  7. How mobile robots have helped at Chernobyl and other accidents

    Energy Technology Data Exchange (ETDEWEB)

    Meieran, H.B.

    1988-04-01

    The use of mobile robots at several recent accidents including Chernobyl is described. The robots assumed, with varying degrees of success, many of the tasks and missions that are normally conducted by the emergency response team. Lessons learned from the experiences, together with operational and performance problems are discussed. (U.K.).

  8. Trees as Filters of Radioactive Fallout from the Chernobyl Accident

    CERN Document Server

    Brownridge, James D

    2011-01-01

    This paper is a copy of an unpublished study of the filtering effect of red maple trees (acer rubrum) on fission product fallout near Binghamton, NY, USA following the 1986 Chernobyl accident. The conclusions of this work may offer some insight into what is happening in the forests exposed to fallout from the Fukushima Daiichi Nuclear Plant accident. This posting is in memory of Noel K. Yeh.

  9. Irradiation of members of the general public from radioactive caesium following the Chernobyl reactor accident. Field studies in a highly contaminated area in the Bryansk region, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Thornberg, C

    2000-11-01

    From 1990 to 1999, estimations of the effective dose from external as well as internal irradiation from {sup 137}Cs and {sup 134}Cs were carried out for inhabitants in rural villages in the Bryansk region, Russia, highly contaminated due to the Chernobyl accident in 1986. The villages were situated about 180 km from the Chernobyl power plant and the deposition of {sup 137}Cs was in the range 0.9-2.7 MBq/m{sup 2}. Yearly expeditions were conducted in autumn by members of the Departments of Radiation Physics in Malmoe and Goeteborg, Institute of Radiation Hygiene, St. Petersburg and the the first 5 years also by the Norwegian Radiation Protection Authority. The dose levels and their change in time were estimated for various groups of the general public. The body burden of {sup 134,137}Cs and hence, the effective dose, was estimated from measurements of the urinary concentration of cesium radionuclides, together with direct measurements of the body content using a portable detector. The effective dose from external irradiation was estimated from measurements with thermoluminescent dosemeters worn by the participants during one month each year. In a special case study, the changes in biokinetics of {sup 137}Cs during pregnancy was investigated in a woman with an unintended intake of {sup 137}Cs via mushrooms from a highly contaminated forest in the area. During pregnancy there is an increased excretion of cesium resulting in a biological half-time of cesium which was 54% of the half-time before pregnancy. The ratio of the {sup 137}Cs concentration in breast milk (Bq/l) to that in the mother's body (Bq/kg) was 15% one month after the child was born. The body burden of {sup 137}Cs in the Russian individuals calculated from the concentration of {sup 137}Cs in urine showed a good agreement with the body burden estimated from in vivo measurements in the same individuals. Normalisation of the cesium concentration in the urine samples by the use of potassium or

  10. Irradiation of members of the general public from radioactive caesium following the Chernobyl reactor accident: Field studies in a highly contaminated area in the Bryansk region, Russia

    Science.gov (United States)

    Thornberg, Charlotte

    From 1990 to 1998, estimations of the effective dose due to irradiation from 137Cs and 134Cs were carried out for inhabitants in rural villages in the Bryansk region, Russia. The villages, situated about 180 km from the Chernobyl power plant received deposition of 137Cs in the range 0.9-2.7 MBq m-2 due to the accident in 1986. The body burden of 137,134Cs was estimated from measurements of the urinary concentration of caesium radionuclides, together with in vivo measurements using a portable detector. The external effective dose was estimated from measurements with thermoluminescent (TL)-dosemeters worn by the participants during one month each year. In a case study, the changes in biokinetics of 137Cs during pregnancy was investigated in a woman with an unintended intake of 137Cs via mushrooms grown in the area. During pregnancy the biological half-time of caesium was 54% of that before pregnancy. The ratio of the 137Cs concentration in breast milk (Bq L-1) to that in the mother's body (Bq kg-1) was 15% one month after the child was born. The body burden of 137Cs in the Russian individuals calculated from urine samples showed a good agreement with the body burden estimated from in vivo measurements in the same individuals. Normalisation of the caesium concentration in the urine samples by the use of potassium or creatinine excretion introduced systematic differences and a larger spread in the calculated values of the 137Cs body burden as compared with calculations without normalisation. The yearly effective dose to inhabitants in the Russian villages varied between 1.2 and 2.5 mSv as a mean for all villages between 1991 and 1998 and the internal effective dose was 30-50% of the total effective dose. The external effective dose decreased on average 15% per year, while the internal effective dose varied, depending to a great extent on the availability of mushrooms. The cumulated effective dose for a 70-year period after the accident was calculated to be 100 m

  11. Internal dose assessment due to large area contamination: Main lessons drawn from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Andrasi, A. [KFKI Atomic Energy Research Inst., Budapest (Hungary)

    1997-03-01

    The reactor accident at Chernobyl in 1986 beside its serious and tragic consequences provided also an excellent opportunity to check, test and validate all kind of environmental models and calculation tools which were available in the emergency preparedness systems of different countries. Assessment of internal and external doses due to the accident has been carried out for the population all over Europe using different methods. Dose predictions based on environmental model calculation considering various pathways have been compared with those obtained by more direct monitoring methods. One study from Hungary and one from the TAEA is presented shortly. (orig./DG)

  12. Compendium of the Environmental Measurements Laboratory's research projects related to the Chernobyl nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Volchok, H L; Chieco, N [comps.

    1986-10-01

    Following the accident at the Chernobyl nuclear reactor power station in the USSR on April 26, 1986, the Environmental Measurements Laboratory (EML) initiated a number of research projects as follows: (1) selected sites in both the Deposition and Surface Air networks were alerted and their sampling protocols adjusted to accommodate the anticipated arrival times and activity concentrations of the Chernobyl debris; (2) a number of cooperative programs involving field work, sampling, analysis and data interpretation were set up with institutions and scientists in other countries; (3) EML's Regional Baseline Station at Chester, NJ, as well as the roof of the Laboratory in New York City, provided bases for sampling and measurements to study the radionuclide concentrations, radiation levels, physical characteristics and potential biological implications of the Chernobyl fallout on the northeastern United States; and (4) the resulting fallout from the Chernobyl accident provided an 'experiment of opportunity' in that it enabled us to study fresh fission product deposition using collection systems resurrected from the 1950's and 1960's for comparison with current state-of-the-art methodology. The 13 reports of this volume have been entered separately into the data base.

  13. Psychosomatic health status of children exposed to the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Korol, N. [Scientific Center for Radiation Medicine, Kiev (Ukraine); Shibata, Yoshisada; Nakane, Yoshibumi

    1998-12-01

    Childhood victims were investigated focussing on the psychosomatic disorders. The subjects were some of the 3834 children who evacuated from the Chernobyl zone to Kiev (evacuees) and 200 children who have been living in Kiev since prior to the accident (comparison group). A psychological test administered to 504 evacuees aged 12-14 years at the time of the accident and the comparison group indicated that the frequencies of neutroticism, high level of anxiety and conflicts were significantly higher in the evacuees than in the comparison group (p<0.001). Another psychological test administered at puberty to the 504 evacuees and 200 other evacuees exposed to the accident at 4-6 years of age indicated that the psycho-emotional portrait of evacuated teenagers significantly changed with time since the accident. The effects of the Chernobyl accident on the health of the vegetative dystonia observed in 1987-1990 and 1990-1995 were higher in the evacuees than in the comparison group, although they were not statistically significant. Furthermore, a significant (p<0.001) association of the vegetative dystonia with peptic and cardiovascular disorders was observed. The present study indicates that the vegetative dystonia is still highly prevalent among childhood victims and deems to support that the vegetative dystonia may be a precursor of several diseases such as cardiovascular and peptic disorders. It should be emphasized that a health promotion program to produce a change in psychological and social problems after the Chernobyl accident is necessary to decrease the health impact among Ukrainian people. (author)

  14. Comparison of the Chernobyl and Fukushima nuclear accidents: A review of the environmental impacts

    Energy Technology Data Exchange (ETDEWEB)

    Steinhauser, Georg, E-mail: georg.steinhauser@colostate.edu; Brandl, Alexander; Johnson, Thomas E.

    2014-02-01

    The environmental impacts of the nuclear accidents of Chernobyl and Fukushima are compared. In almost every respect, the consequences of the Chernobyl accident clearly exceeded those of the Fukushima accident. In both accidents, most of the radioactivity released was due to volatile radionuclides (noble gases, iodine, cesium, tellurium). However, the amount of refractory elements (including actinides) emitted in the course of the Chernobyl accident was approximately four orders of magnitude higher than during the Fukushima accident. For Chernobyl, a total release of 5300 PBq (excluding noble gases) has been established as the most cited source term. For Fukushima, we estimated a total source term of 520 (340–800) PBq. In the course of the Fukushima accident, the majority of the radionuclides (more than 80%) was transported offshore and deposited in the Pacific Ocean. Monitoring campaigns after both accidents reveal that the environmental impact of the Chernobyl accident was much greater than of the Fukushima accident. Both the highly contaminated areas and the evacuated areas are smaller around Fukushima and the projected health effects in Japan are significantly lower than after the Chernobyl accident. This is mainly due to the fact that food safety campaigns and evacuations worked quickly and efficiently after the Fukushima accident. In contrast to Chernobyl, no fatalities due to acute radiation effects occurred in Fukushima. - Highlights: • The environmental effects of Chernobyl and Fukushima are compared. • Releases of radionuclides from Chernobyl exceeded Fukushima by an order of magnitude. • Chernobyl caused more severe radiation-related health effects. • Overall, Chernobyl was a much more severe nuclear accident than Fukushima. • Psychological effects are neglected but important consequences of nuclear accidents.

  15. Management, administrative and operational causes of the accident: Chernobyl nuclear power station

    Energy Technology Data Exchange (ETDEWEB)

    Anastas, G. [California State Univ., Sacramento, CA (United States)

    1996-10-01

    The Chernobyl accident, which occurred in April 1986, was the result of management, administrative, operational, technical and design flaws. The accident released millions of curies of mixed fission products including 70-100 PBq of {sup 137}Cs. At the time of the accident, science, engineering and safety in the former Soviet Union were dominated by an atmosphere of politics, group think and `dingoes tending the sheep`. This corrupted safety culture exacerbated the poor design of the reactor. The results of this study strongly suggest that the cultural, political, managerial and operational attributes of the Soviet `system` performed in a synergistic manner to significantly contribute to the initiation of the accident. (authors). 16 refs.

  16. Airborne and deposited radioactivity from the Chernobyl accident. A review of investigations in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Paatero, J. (Finnish Meteorogical Inst., Helsinki (Finland)); Haemeri, K. (Helsinki Univ., Dept. of Physics (Finland)); Jaakkola, T. (Helsinki Univ., Lab. of Radiochemistry (Finland)); Jantunen, M. (National Public Health Inst., Kuopio (Finland)); Koivukoski, J. (Ministry of the Interior, Rescue Dept., Government (Finland)); Saxen, R. (STUK Radiation and Nuclear Safety Authority, Helsinki (Finland))

    2010-07-01

    The Chernobyl nuclear accident happened in the former Soviet Union on 26 April 1986. The accident destroyed one of the RBMK-1000 type reactors and released significant radioactive contamination into the environment. At first the emissions were transported north-westwards over Poland, the Baltic States, Finland, Sweden and Norway. During 27 April 1986 emissions were spreading to eastern-central Europe, southern Germany, Italy and Yugoslavia. Radioactivity mapping over Finland between 29 April and 16 May 1986 showed that the ground deposition in Finland covered southern and central parts of the country but had an irregular distribution. The highest (over 100 muR h-1 [1 muSv h-1]) contamination disclosed by the mapping was around the city of Uusikaupunki in western Finland and the city of Kotka in southeastern Finland. The Uusikaupunki region was an area of heavy fallout associated with the air mass that was located in the Chernobyl area at the time of the accident. The fallout pattern of reftractory nuclides, e.g. plutonium isotopes, had their spatial maximum in this region. Medical consequences in Finland were luckily mild, the most important symptoms being psychological ones. No increase in thyroid cancer or birth defect occurrence has been observed. The Chernobyl accident boosted the radioecological research which had already been calming down after the last atmospheric nuclear test in China in October 1980. Important new results concerning e.g. hot particles have been achieved. The most important effects of the accident in Finland were, however, the increase of public awareness of environmental issues in general and especially of nuclear energy. In Finland, the nuclear energy programme was halted until 2002 when the Parliament of Finland granted a licence to build the fifth nuclear reactor in Finland. (orig.)

  17. Comparison of the Chernobyl and Fukushima nuclear accidents: a review of the environmental impacts.

    Science.gov (United States)

    Steinhauser, Georg; Brandl, Alexander; Johnson, Thomas E

    2014-02-01

    The environmental impacts of the nuclear accidents of Chernobyl and Fukushima are compared. In almost every respect, the consequences of the Chernobyl accident clearly exceeded those of the Fukushima accident. In both accidents, most of the radioactivity released was due to volatile radionuclides (noble gases, iodine, cesium, tellurium). However, the amount of refractory elements (including actinides) emitted in the course of the Chernobyl accident was approximately four orders of magnitude higher than during the Fukushima accident. For Chernobyl, a total release of 5,300 PBq (excluding noble gases) has been established as the most cited source term. For Fukushima, we estimated a total source term of 520 (340-800) PBq. In the course of the Fukushima accident, the majority of the radionuclides (more than 80%) was transported offshore and deposited in the Pacific Ocean. Monitoring campaigns after both accidents reveal that the environmental impact of the Chernobyl accident was much greater than of the Fukushima accident. Both the highly contaminated areas and the evacuated areas are smaller around Fukushima and the projected health effects in Japan are significantly lower than after the Chernobyl accident. This is mainly due to the fact that food safety campaigns and evacuations worked quickly and efficiently after the Fukushima accident. In contrast to Chernobyl, no fatalities due to acute radiation effects occurred in Fukushima.

  18. Radionuclides contamination of fungi after accident on the Chernobyl NPP

    Energy Technology Data Exchange (ETDEWEB)

    Zarubina, Nataliia E.; Zarubin, Oleg L. [Institute for Nuclear Research of National Academy of Sciense, 03680, pr-t Nauki, 47, Kiev (Ukraine)

    2014-07-01

    Accumulation of radionuclides by the higher fungi (macromycetes) after the accident on the Chernobyl atomic power plant in 1986 has been studied. Researches were spent in territory of the Chernobyl alienation zone and the Kiev region. Our research has shown that macromycetes accumulate almost all types of radionuclides originating from the accident ({sup 131}I, {sup 140}Ba /{sup 140}La, {sup 103}Ru, {sup 106}Ru, {sup 141}Ce, {sup 144}Ce, {sup 95}Nb, {sup 95}Zr, {sup 137}Cs and {sup 134}Cs). They accumulate the long-living {sup 90}Sr in much smaller (to 3 - 4 orders) quantities than {sup 137}Cs. We have established existence of two stages in accumulation of {sup 137}Cs by higher fungi after the accident on the Chernobyl NPP: the first stage resides in the growth of the concentration, the second - in gradual decrease of levels of specific activity of this radionuclide. Despite reduction of {sup 137}Cs specific activity level, the content of this radionuclide at testing areas of the 5-km zone around the Chernobyl NPP reaches 1,100,000 Bq/kg of fresh weight in 2013. We investigated dynamics of accumulation of Cs-137 in higher fungi of different ecological groups. One of the major factors that influence levels of accumulation of {sup 137}Cs by fungi is their nutritional type (ecological group). Fungi that belong to ecological groups of saprotrophes and xylotrophes accumulate this radionuclide in much smaller quantities than symbio-trophic fungi. As a result of the conducted research it has been established that symbio-trophic fungi store more {sup 137}Cs than any other biological objects in forest ecosystems. Among the symbio-trophic fungi species, species showing the highest level of {sup 137}Cs contamination vary in different periods of time after the deposition. It is connected with variability of quantities of these radio nuclides accessible for absorption at the depth of localization of the main part of mycelium of each species in a soil profile. Soil contamination

  19. [Remote effects of the Chernobyl accident: evaluation of the maxillodental status of the children].

    Science.gov (United States)

    Sevbitov, A V

    2004-01-01

    Examinations of children exposed to the Chernobyl factor showed deterioration of the maxillodental status, presenting as a decrease in the incidence of normal-for-age status in comparison with children from the control group. The incidence of dental abnormalities in children whose parents participated in the Chernobyl accident aftermath is increased by 240,09%. The determination of remote effects of the Chernobyl accident for the health status of Russian children requires a differentiated approach and deserves a special study.

  20. Estimated long term health effects of the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Cardis, E. [International Agency for Research on Cancer, Lyon (France)

    1996-07-01

    Apart from the dramatic increase in thyroid cancer in those exposed as children, there is no evidence to date of a major public health impact as a result of radiation exposure due to the Chernobyl accident in the three most affected countries (Belarus, Russia, and Ukraine). Although some increases in the frequency of cancer in exposed populations have been reported ,these results are difficult to interpret, mainly because of differences in the intensity and method of follow-up between exposed populations and the general population with which they are compared. If the experience of the survivors of the atomic bombing of Japan and of other exposed populations is applicable, the major radiological impact of the accident will be cases of cancer. The total lifetime numbers of excess cancers will be greatest among the `liquidators` (emergency and recovery workers) and among the residents of `contaminated` territories, of the order of 2000 to 2500 among each group (the size of the exposed populations is 200,000 liquidators and 3,700,000 residents of `contaminated` areas). These increases would be difficult to detect epidemiologically against an expected background number of 41500 and 433000 cases of cancer respectively among the two groups. The exposures for populations due to the Chernobyl accident are different in type and pattern from those of the survivors of the atomic bombing of Japan. Thus predictions derived from studies of these populations are uncertain. The extent of the incidence of thyroid cancer was not envisaged. Since only ten years have lapsed since the accident, continued monitoring of the health of the population is essential to assess the public health impact.

  1. RADIOACTIVE WASTE MANAGEMENT IN THE CHERNOBYL EXCLUSION ZONE - 25 YEARS SINCE THE CHERNOBYL NUCLEAR POWER PLANT ACCIDENT

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.

    2011-10-01

    Radioactive waste management is an important component of the Chernobyl Nuclear Power Plant accident mitigation and remediation activities of the so-called Chernobyl Exclusion Zone. This article describes the localization and characteristics of the radioactive waste present in the Chernobyl Exclusion Zone and summarizes the pathways and strategy for handling the radioactive waste related problems in Ukraine and the Chernobyl Exclusion Zone, and in particular, the pathways and strategies stipulated by the National Radioactive Waste Management Program. The brief overview of the radioactive waste issues in the ChEZ presented in this article demonstrates that management of radioactive waste resulting from a beyond-designbasis accident at a nuclear power plant becomes the most challenging and the costliest effort during the mitigation and remediation activities. The costs of these activities are so high that the provision of radioactive waste final disposal facilities compliant with existing radiation safety requirements becomes an intolerable burden for the current generation of a single country, Ukraine. The nuclear accident at the Fukushima-1 NPP strongly indicates that accidents at nuclear sites may occur in any, even in a most technologically advanced country, and the Chernobyl experience shows that the scope of the radioactive waste management activities associated with the mitigation of such accidents may exceed the capabilities of a single country. Development of a special international program for broad international cooperation in accident related radioactive waste management activities is required to handle these issues. It would also be reasonable to consider establishment of a dedicated international fund for mitigation of accidents at nuclear sites, specifically, for handling radioactive waste problems in the ChEZ. The experience of handling Chernobyl radioactive waste management issues, including large volumes of radioactive soils and complex structures

  2. Validity aspects in Chernobyl at twenty years of the accident; Aspectos vigentes en Chernobyl a veinte anos del accidente

    Energy Technology Data Exchange (ETDEWEB)

    Arredondo, C. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: cas@nuclear.inin.mx

    2006-07-01

    For April 25, 1986 the annual stop of the unit 4 of the nuclear power plant of Chernobyl was programmed, in order to carry out maintenance tasks. This unit was equipped with a reactor of 1000 MW, type RBMK, developed in the former Soviet Union, this type of reactors uses graphite like moderator, the core is refrigerated with common water in boil, and the fuel is uranium enriched to 2%. Also it had been programmed to carry out, before stopping the operation of the power station, a test with one of the two turbogenerators, which would not affect to the reactor. However, the intrinsic characteristics of the design of the reactor and the fact that the operators disconnected intentionally several systems of security that had stopped the reactor automatically, caused a decontrolled increase of the power (a factor 1000 in 4 seconds), with the consequent fusion of the fuel and the generation of a shock wave, produced by the fast evaporation of the refrigeration water and caused by the interaction of the fuel fused with the same one. It broke the core in pieces and destroy the structure of the reactor building that was not resistant to the pressure. When being exposed to the air, the graphite of the moderator entered in combustion, while the radioactive material was dispersed in the environment. The radionuclides liberation was prolong during 10 days, and only it was stopped by means of the one poured from helicopters, of some 5000 tons of absorbent materials on the destroyed reactor, as long as tunnels were dug to carry out the cooling of the core with liquid nitrogen. Later on, the whole building of the damaged reactor was contained inside a concrete building. The immediate consequence of the accident was the death of 31 people, between operators of the nuclear power station and firemen. One of people died as consequence of the explosion and 30 died by cause of the irradiation, with dose of the order of 16 Gy. The liberated radioactive material was the entirety of the

  3. RADIOLOGICAL AND MEDICAL CONSEQUENCES OF THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    V. G. Bebeshko

    2012-01-01

    Full Text Available From the position of a 25-years’ experience to overcome the health effects of Chernobyl the dynamics of the radiation environment, the first summarizing at the international level (1988, the results of completed research and practical monitoring are analyzed. Cohort of acute radiation syndrome (ARS survivors under medical observation at the S.I. "Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine" is the largest. Within the 25 years the functional state of the major organs and body systems, and metabolic homeostasis for this category of persons were studied, a comprehensive assessment of their health, mental and physical performance were given, and risk factors and peculiarities of stochastic and non-stochastic pathology courses were identified, as well as a system of rehabilitation patients after ARS was developed. ARS survivors are suffering from chronic diseases of internal organs and systems (from 5-7 to 10-12 diagnoses at the same time. A correlation between acute radiation effects and specific HLA phenotypes were revealed. The dynamics of the immune system recovery after irradiation was studied. The role and prognostic value of telomere length and programmed cell death of lymphocytes in the formation of the cellular effects of ionizing radiation were determined for the first time. Differences between spontaneous and radiation-induced acute myeloid leukemias were found. Dose-dependent neuropsychiatric, neurophysiological, neuropsychological and neuroimaging deviations were identified after irradiation at doses above 0.3 Sv. It was shown that the lymphocytes of Chernobyl clean-up workers with doses 350 – 690 mGy can induce "the bystander effect" in the non-irradiated cells even after 19 years after exposure. The rates of cancer incidence and mortality of victims, the lessons and key problems to be solved in the third decade after the Chernobyl accident are considered.

  4. Consequences of the Chernobyl accident for reindeer husbandry in Sweden

    Directory of Open Access Journals (Sweden)

    Gustaf Åhman

    1990-09-01

    Full Text Available Large parts of the reindeer hearding area in Sweden were contaminated with radioactive caesium from the Chernobyl fallout. During the first year after the accident no food with activity concentrations exceeding 300 Bq/kg was allowed to be sold in Sweden. This meant that about 75% of all reindeer meat produced in Sweden during the autumn and winter 1986/87 were rejected because of too high caesium activités. In May 1987 the maximum level for Cs-137 in reindeer, game and fresh-water fish was raised to 1500 Bq/kg. During the last two year, 1987/88 and 1988/89, about 25% of the slaughtered reindeer has had activities exceeding this limit. The effective long-time halflife or radiocaesium in reindeer after the nuclear weapon tests in the sixties was about 7 years. If this halflife is correct also for the Chernobyl fallout it will take about 35 years before most of the reinder in Sweden are below the current limit 1500 Bq/kg in the winter. However, by feeding the animals uncontaminated food for about two months, many reindeer can be saved for human consumption.

  5. The French-German initiative for Chernobyl: programme 3: Health consequences of the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Tirmarche, M. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Radiological Protection and Human Health Div. (DRPH), Radiobiology and Epidemiology Dept., 92 - Fontenay-aux-Roses (France); Kellerer, A.M. [Munchen Univ., Strahlenbiologisches Institut (Germany); Bazyka, D. [Chornobyl Center (CC), Kiev regoin (Ukraine)

    2006-07-01

    - Goals: The main objectives of the health programme are collection and validation of existing data on cancer and non cancer diseases in the most highly contaminated regions of Ukraine, Russia and Belarus, common scientific expertise on main health indicators and reliable dosimetry, and finally communication of the results to the scientific community and to the public. - General Tasks: 1- Comparison between high and low exposed regions, 2- Description of trends over time, 3- Consideration of specific age groups. This methodological approach is applied on Solid cancer incidence and leukaemia incidence in different regions in Ukraine, Belarus and Russia, With a special focus on thyroid cancer in young exposed ages. - Thyroid cancer: Those exposed in very young ages continue to express a relatively high excess of thyroid cancer even though they have now reached the age group 15-29. Those exposed as young adults show a small increase, at least partly due to better screening conditions - Leukemia: Description of leukemia trends for various age groups show no clear difference between exposed and unexposed regions when focusing on those exposed at very young ages. The rates of childhood leukemia before and after the accident show no evidence of any increase (oblasts in Belarus over 1982-1998). - Specific studies: Incidence of congenital malformations in Belarus; Infant mortality and morbidity in the most highly contaminated regions; Potential effects of prenatal irradiation on the brain as a result of the Chernobyl accident; Nutritional status of population living in regions with different levels of contamination; Dosimetry of Chernobyl clean-up workers; Radiological passports in contaminated settlements. - Congenital malformations: As a national register was existing since the 1980's and gives the possibility to compare trends before and after the accident, results of congenital malformations describe large results collected over Belarus, There is no evidence of a

  6. Cancer incidence in children after the Chernobyl reactor accident. Report prepared within the framework of the radiobiological environmental monitoring programme in Bavaria; Inzidenz boesartiger Neubildungen bei Kindern nach dem Reaktorunfall von Tschernobyl. Bericht im Rahmen des Strahlenbiologischen Umweltmonitorings Bayern

    Energy Technology Data Exchange (ETDEWEB)

    Irl, C.; Schoetzau, A.; Santen, F. von; Grosche, B.

    1996-04-01

    The impact of the radiological contamination in Bavaria after the Chernobyl accident on childhood cancer was evaluated. According to caesium 137 in soil samples, Bavaria was subdivided in four regions with different contamination levels. The malignancies selected for analysis were: Leukaemia and non-Hodgkin lymphoma, tumors orginating in the embryonic period, tumors of the central nervous system and thyroid cancer. The temporal changes in the incidence of the selected tumors in the four regions were compared with the temporal changes in the rest of the Federal Republic of Germany (old laender). In addition, it was investigated, whether the tumor incidence after the Chernobyl accident showed a trend in connection with the degree of contamination. The results of the study neither show significant differences in the tumor incidence of regions with different contamination levels, nor are they indicative of a trend in the incidence in relation with contamination. Consequently, this study provides no evidence that the Chernobyl accident caused an increase in childhood cancer. Considering the latency periods of malignant diseases, however, a final evaluation is not yet possible. (orig.) [Deutsch] Der vorliegende Bericht untersucht die Frage einer nach dem Reaktorunfall in Tschernobyl erhoehten Inzidenz boesartiger Neubildungen bei Kindern in Bayern, demjenigen unter den alten Bundeslaendern, das durch den Unfall am staerksten kontaminiert wurde. Von den boesartigen Neubildungen wurden solche ausgewaehlt, bei denen ionisierende Strahlung als ein aetiologisch relevanter Faktor in Frage kommt. Im einzelnen handelt es sich um die Gruppe der Leukaemien und Non-Hodgkin-Lymphome, Tumoren mit Ursprung in der Embryonalzeit (maligne Keimzelltumoren, Nephroblastom, Neuroblastom, Retinoblastom), Tumoren des Zentrahnervensystems und Schilddruesenkarzinome. Die Analyse besteht einerseits in einem Vergleich zwischen unterschiedlich hohen exponierten Bevoelkerungsgruppen Bayerns mit der

  7. INTERNATIONAL ASSESSMENTS OF IMPACTS OF THE CHERNOBYL ACCIDENT: THE CHERNOBYL FORUM (2003–2005 AND UNSCEAR (2005–2008

    Directory of Open Access Journals (Sweden)

    M. I. Balonov

    2011-01-01

    Full Text Available Radiological consequences of the accident at the Chernobyl NPP were recently revisited by the UN Chernobyl Forum (2003-2005 and UNSCEAR (2005-2008. For the first time environmental impacts were considered in detail, including radioactive contamination of terrestrial and aquatic environments, application and effectiveness of countermeasures and effects on biota. Updated dosimetric data were presented for more than half a million of emergency and recovery operation workers, about 100 million inhabitants of the three most affected countries, Belarus, the Russian Federation and Ukraine, and for 500 million inhabitants of other European countries. Several hundred of the emergency workers received high radiation doses; of whom 28 persons died in 1986 due to acute radiation sickness. Children at the time of the accident, who drank milk with high levels of radioactive iodine, received high doses to the thyroid. Since early 1990s there was the dramatic increase in thyroid cancer incidence among them. Also in 1990s there was some increase of leukaemia in most exposed workers. The UN Chernobyl Forum concluded that severe social and economic depression of the affected regions and associated psychological problems of the general public and the workers had become the most significant problem. The vast majority of the population need not live in fear of serious health consequences from the Chernobyl accident.

  8. Radiocesium in lichens and reindeer after the Chernobyl accident

    Directory of Open Access Journals (Sweden)

    K. Rissanen

    1990-09-01

    Full Text Available After the Chernobyl accident the sampling and measuring program of the Finnish Centre for Radiation and Nuclear Safety was intensified both for surveillance and research purposes. The deposition pattern of radionuclides was more complicated than from the global fallout after the nuclear weapons tests. The radioactive deposition was very unevenly distributed in Lapland, as also in the rest of Finland. Fortunately, the amounts of deposition in Lapland were only about one-tenth of the corresponding amount of deposition in southern Finland. In 1986-87 the mean concentration of Cs-137 in lichens and in reindeer meat increased to about the same level as in 1972-73 or to about 30 per cent of the maximum levels found in 1964-65 after the nuclear weapons tests. The activity concentrations in reindeer tissues vary according to season. In winter, reindeer eat considerable amounts of lichens with high radiocesium concentrations. In summer, lichens are replaced by other forage such as leaves from trees, green plants, etc. The ratio of Cs-137 concentration in reindeer meat between summer and winter is about 0.2. The mean concentration of Cs-137 in meat for consumption from the slaughtering period 1986-87 was 720 Bq/kg fresh weight. After that time concentrations started decreasing since no new fallout was deposited.

  9. International program on the health effects of the Chernobyl accident.

    Science.gov (United States)

    Kreisel, W

    1995-05-01

    The International Program on the Health Effects of the Chernobyl Accident (IPHECA) was established by the World Health Organization (WHO) in 1991. Currently, the technical part of IPHECA consists of five projects addressing the following areas of priority health problems or needs: thyroid, hematology, brain damage in utero, epidemiological registry and oral health. Important findings are: 1) a significant increase of thyroid cancer in children in Belarus and Ukraine since 1989, and in Russia since 1992 though not so pronounced. A relationship between detected thyroid cancers and radiation exposure is yet to be established, 2) no increase yet in the incidence of hemoblastoses in the three States, 3) no relationship established between mental retardation and radiation exposure in utero in 4,500 children investigated. The importance of dosimetry and biological indicators of radiation damage has been recognized by IPHECA. Several methods of biological and physical dosimetry are being employed using instrumentation provided by IPHECA. Some preliminary results indicate: 1) unstable aberrations can indicate an integral exposure but it is heavily biased to recent exposures, 2) when comparing healthy persons and patients with hematological diseases in contaminated areas, there is a higher ratio of total aberrations compared to their background and that the level of stable is lower than unstable aberrations, and 3) by applying electron spin resonance (ESR) it has been shown that the individual distribution of doses approaches a log-normal one, especially for adults, and that a peak shift towards higher doses is noticeable for children.

  10. Fallout from Chernobyl [Letters to the editor

    Energy Technology Data Exchange (ETDEWEB)

    Williams, E.D. (Addenbrooke' s Hospital, Cambridge (United Kingdom)); Abelin, T.; Egger, M. (Bern Univ. (Switzerland)) (and others)

    1994-11-12

    Six brief letters discuss the possible health effects of fallout from the Chernobyl reactor accident including an increase in thyroid cancer in children in Belarus, chromosomal abnormalities in workers from Latvia who cleared up the Chernobyl accident site, an increased trisomy 21 in Berlin but a lack of increased childhood leukaemia incidence in Greece. (UK).

  11. Chernobyl post-accident management: the ETHOS project.

    Science.gov (United States)

    Dubreuil, G H; Lochard, J; Girard, P; Guyonnet, J F; Le Cardinal, G; Lepicard, S; Livolsi, P; Monroy, M; Ollagnon, H; Pena-Vega, A; Pupin, V; Rigby, J; Rolevitch, I; Schneider, T

    1999-10-01

    ETHOS is a pilot research project supported by the radiation protection research program of the European Commission (DG XII). The project provides an alternative approach to the rehabilitation of living conditions in the contaminated territories of the CIS in the post-accident context of Chernobyl. Initiated at the beginning of 1996, this 3-y project is currently being implemented in the Republic of Belarus. The ETHOS project involves an interdisciplinary team of European researchers from the following institutions: the Centre d'etude sur l'Evaluation de la Protection dans le domaine Nucleaire CEPN (radiological protection, economics), the Institute National d'Agronomie de Paris-Grignon INAPG (agronomy, nature & life management), the Compiegne University of Technology (technological and industrial safety, social trust), and the Mutadis Research Group (sociology, social risk management), which is in charge of the scientific co-ordination of the project. The Belarussian partners in the ETHOS project include the Ministry of Emergencies of Belarus as well as the various local authorities involved with the implementation site. The ETHOS project relies on a strong involvement of the local population in the rehabilitation process. Its main goal is to create conditions for the inhabitants of the contaminated territories to reconstruct their overall quality of life. This reconstruction deals with all the day-to-day aspects that have been affected or threatened by the contamination. The project aims at creating a dynamic process whereby acceptable living conditions can be rebuilt. Radiological security is developed in the ETHOS project as part of a general improvement in the quality of life. The approach does not dissociate the social and the technical dimensions of post-accident management. This is so as to avoid radiological risk assessment and management being reduced purely to a problem for scientific experts, from which local people are excluded, and to take into

  12. Chernobyl nuclear accident revealed from the 7010 m Muztagata ice core record

    Institute of Scientific and Technical Information of China (English)

    TIAN LiDe; YAO TanDong; WU GuangJian; LI Zhen; XU BaiQing; LI YueFang

    2007-01-01

    The total activity variation with depth from a 41.6 m Muztagata ice core drilled at 7010 m,recorded not only the 1963 radioactive layer due to the thermonuclear test,but also clearly the radioactive peak released by the Chernobyl accident in 1986.This finding indicates that the Chernobyl nuclear accident was clearly recorded in alpine glaciers in the Pamirs of west China,and the layer can be potentially used for ice core dating in other high alpine glaciers in the surrounding regions.

  13. Twenty years' application of agricultural countermeasures following the Chernobyl accident: lessons learned

    Energy Technology Data Exchange (ETDEWEB)

    Fesenko, S V [International Atomic Energy Agency, 1400 Vienna (Austria); Alexakhin, R M [Russian Institute of Agricultural Radiology and Agroecology, 249020 Obninsk (Russian Federation); Balonov, M I [International Atomic Energy Agency, 1400 Vienna (Austria); Bogdevich, I M [Research Institute for Soil Science and Agrochemistry, Minsk (Belarus); Howard, B J [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LAI 4AP (United Kingdom); Kashparov, V A [Ukrainian Institute of Agricultural Radiology (UIAR), Mashinostroiteley Street 7, Chabany, Kiev Region 08162 (Ukraine); Sanzharova, N I [Russian Institute of Agricultural Radiology and Agroecology, 249020 Obninsk (Russian Federation); Panov, A V [Russian Institute of Agricultural Radiology and Agroecology, 249020 Obninsk (Russian Federation); Voigt, G [International Atomic Energy Agency, 1400 Vienna (Austria); Zhuchenka, Yu M [Research Institute of Radiology, 246000 Gomel (Belarus)

    2006-12-15

    The accident at the Chernobyl NPP (nuclear power plant) was the most serious ever to have occurred in the history of nuclear energy. The consumption of contaminated foodstuffs in affected areas was a significant source of irradiation for the population. A wide range of different countermeasures have been used to reduce exposure of people and to mitigate the consequences of the Chernobyl accident for agriculture in affected regions in Belarus, Russia and Ukraine. This paper for the first time summarises key data on countermeasure application over twenty years for all three countries and describes key lessons learnt from this experience. (review)

  14. Global risk of radioactive fallout after major nuclear reactor accidents

    Science.gov (United States)

    Lelieveld, J.; Kunkel, D.; Lawrence, M. G.

    2012-05-01

    Major reactor accidents of nuclear power plants are rare, yet the consequences are catastrophic. But what is meant by "rare"? And what can be learned from the Chernobyl and Fukushima incidents? Here we assess the cumulative, global risk of exposure to radioactivity due to atmospheric dispersion of gases and particles following severe nuclear accidents (the most severe ones on the International Nuclear Event Scale, INES 7), using particulate 137Cs and gaseous 131I as proxies for the fallout. Our results indicate that previously the occurrence of INES 7 major accidents and the risks of radioactive contamination have been underestimated. Using a global model of the atmosphere we compute that on average, in the event of a major reactor accident of any nuclear power plant worldwide, more than 90% of emitted 137Cs would be transported beyond 50 km and about 50% beyond 1000 km distance before being deposited. This corroborates that such accidents have large-scale and trans-boundary impacts. Although the emission strengths and atmospheric removal processes of 137Cs and 131I are quite different, the radioactive contamination patterns over land and the human exposure due to deposition are computed to be similar. High human exposure risks occur around reactors in densely populated regions, notably in West Europe and South Asia, where a major reactor accident can subject around 30 million people to radioactive contamination. The recent decision by Germany to phase out its nuclear reactors will reduce the national risk, though a large risk will still remain from the reactors in neighbouring countries.

  15. Global risk of radioactive fallout after major nuclear reactor accidents

    Directory of Open Access Journals (Sweden)

    J. Lelieveld

    2012-05-01

    Full Text Available Major reactor accidents of nuclear power plants are rare, yet the consequences are catastrophic. But what is meant by "rare"? And what can be learned from the Chernobyl and Fukushima incidents? Here we assess the cumulative, global risk of exposure to radioactivity due to atmospheric dispersion of gases and particles following severe nuclear accidents (the most severe ones on the International Nuclear Event Scale, INES 7, using particulate 137Cs and gaseous 131I as proxies for the fallout. Our results indicate that previously the occurrence of INES 7 major accidents and the risks of radioactive contamination have been underestimated. Using a global model of the atmosphere we compute that on average, in the event of a major reactor accident of any nuclear power plant worldwide, more than 90% of emitted 137Cs would be transported beyond 50 km and about 50% beyond 1000 km distance before being deposited. This corroborates that such accidents have large-scale and trans-boundary impacts. Although the emission strengths and atmospheric removal processes of 137Cs and 131I are quite different, the radioactive contamination patterns over land and the human exposure due to deposition are computed to be similar. High human exposure risks occur around reactors in densely populated regions, notably in West Europe and South Asia, where a major reactor accident can subject around 30 million people to radioactive contamination. The recent decision by Germany to phase out its nuclear reactors will reduce the national risk, though a large risk will still remain from the reactors in neighbouring countries.

  16. [Specific Features of Scots Pine Seeds Formation in the Remote Period after the Chernobyl NPP Accident].

    Science.gov (United States)

    Geras'kin, S A; Vasiliev, D V; Kuzmenkov, A G

    2015-01-01

    The results of long-term (2007-2011) observations on the quality of seed progeny in Scots pine populations inhabiting the sites within the Bryansk region contaminated as a result of the Chernobyl NPP accident are presented. Formed under the chronic exposure seeds are characterized by a high interannual variability, which is largely determined by weather conditions.

  17. Thyroid examination in highly radiation-exposed workers after the Chernobyl accident

    NARCIS (Netherlands)

    B.O. Boehm (Bernhard); M. Steinert (Marianna); J.W. Dietrich (Johannes); R.U. Peter (Ralf Uwe); D. Belyi (David); G. Wagemaker (Gerard); S. Rosinger (Silke); T.M. Friedner (Theodor); M. Weiss (Melanie)

    2009-01-01

    textabstractContext: Radioactive contamination from the Chernobyl nuclear accident that happened on the morning of 26th April 1986 had a major impact on thyroid health in the Belarus region. Objective: Observational study of a cohort of 99 adults, most strongly exposed to ionizing radioactivity. Des

  18. RADIATION HYGIENIC CONSEQUENCES OF THE ACCIDENT AT THE CHERNOBYL NPP AND THE TASKS OF THEIR MINIMIZATION

    Directory of Open Access Journals (Sweden)

    G. G. Onischenko

    2009-01-01

    Full Text Available The paper presents data on the role and results of activities of Rospotrebnadzor bodies and institutions in the field of ensuring population radiation protection during various periods since accident at the Chernobyl NPP. Radiation hygienic characterization of territories affected by radioactive contamination from the accident, population exposure dose range, issues of ensuring radiological well-being of population and ways of their solution are being presented in the paper.

  19. Global risk of radioactive fallout after nuclear reactor accidents

    Science.gov (United States)

    Kunkel, D.; Lelieveld, J.; Lawrence, M. G.

    2012-04-01

    Reactor core meltdowns of nuclear power plants are rare, yet the consequences are catastrophic. But what is meant by "rare"? And what can be learned from the Chernobyl and Fukushima incidents? Here we assess the risk of exposure to radioactivity due to atmospheric dispersion of gases and particles following severe nuclear accidents, using particulate 137Cs and gaseous 131I as proxies for the fallout. It appears that previously the occurrence of major accidents and the risks of radioactive contamination have been underestimated. Using a global model of the atmosphere we compute that on average, in the event of a core melt of any nuclear power plant worldwide, more than 90 % of emitted 137Cs would be transported beyond 50 km and about 50 % beyond 1000 km distance. This corroborates that such accidents have large-scale and trans-boundary impacts. Although the emission strengths and atmospheric removal processes of 137Cs and 131I are quite different, the radioactive contamination patterns over land and the human deposition exposure are computed to be similar. High human exposure risks occur around reactors in densely populated regions, notably in southern Asia where a core melt can subject 55 million people to radioactive contamination. The recent decision by Germany to phase out its nuclear reactors will reduce the national risk, though a large risk will still remain from the reactors in neighbouring countries.

  20. Studies of radiological consequences on the reports of Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Asano, Takeyoshi [Research Institute for Advanced Science and Technology, Osaka Prefecture Univ., Sakai, Osaka (Japan)

    1999-09-01

    1) Relation of radiation related quantities such as radioactivity, exposure, absorbed dose, dose equivalent, effective dose equivalent and radiation protection standards were explained as easy as a beginner could understand. 2) Using published data including IAEA data in the report 'One Decade After Chernobyl (Summary of the Conference Results, 1996)' and some reports, outline of explosion, exposure dose and radiation effects which gave to the human body were briefly described and some rational ways for understanding the data were shown. (author)

  1. Modelling transport and deposition of caesium and iodine from the Chernobyl accident using the DREAM model

    Directory of Open Access Journals (Sweden)

    J. Brandt

    2002-06-01

    Full Text Available A tracer model, DREAM (the Danish Rimpuff and Eulerian Accidental release Model, has been developed for modelling transport, dispersion and deposition (wet and dry of radioactive material from accidental releases, as the Chernobyl accident. The model is a combination of a Lagrangian model, that includes the near source dispersion, and an Eulerian model describing the long-range transport. The performance of the transport model has previously been tested within the European Tracer Experiment, ETEX, which included transport and dispersion of an inert, non-depositing tracer from a controlled release. The focus of this paper is the model performance with respect to the deposition of 137Cs, 134Cs and 131I from the Chernobyl accident, using different relatively simple and comprehensive parameterizations. The performance, compared to measurements, of different combinations of parameterizations of wet and dry deposition schemes has been evaluated, using different statistical tests.

  2. Re-evaluation of internal exposure from the Chernobyl accident to the Czech population

    Energy Technology Data Exchange (ETDEWEB)

    Malatova, I.; Skrkal, J. [National Radiation Protection Institute, Srobarova (Czech Republic)

    2006-07-01

    Doses from internal and external exposure due to the Chernobyl accident to the Czech population were estimated early in 1986. Later on, with more eimental results, doses from internal exposure were calculated more precisely. The initial predictions were rather conservative leading thus to higher doses than it appeared one year later. Monitoring of the environment, food chain and monitoring of internal contamination has been performed on the whole territory of the country since 1986 up to present time and has thus enabled reevaluation of the original estimates and also prediction of doses in future. This paper is focused mainly on evaluation of in vivo measurements of people. Use of the sophisticate software I.M.B.A. Professional Plus led to new estimation of committed effective doses and calculated inhalation intakes of radionuclides lead to estimation of content of radionuclides in the air. Ingestion intakes were also evaluated and compared with estimates from the results of measurements of food chain. Generally, the doses from the Chernobyl accident to the Czech population were low; however, as a few radionuclides have been measurable in environment, food chain and human body (137 Cs up to present), it is a unique chance for studying behaviour of radionuclides in the biosphere. Experience and conclusions which follow from the monitoring of the Chernobyl accident are unique for running and development of monitoring networks. Re evaluation of internal doses to the Czech population from the Chernobyl accident, using alternative approach, gave generally smaller doses than original estimation; still, the difference was not significant. It was shown that the doses from inhalation of 131 I and 137 Cs were greater than originally estimated, whereas doses from ingestion intake were lower than the originally estimated ones. (authors)

  3. The spatial distribution of caesium-137 over Northern Ireland from fallout from the Chernobyl nuclear accident

    OpenAIRE

    Rawlins, B. G.; Scheib, C.; Tyler, A.N.; Jones, D.; Webster, R; Young, M. E.

    2009-01-01

    The spatial distribution of caesium-137 (137Cs) across the land is of much interest because it can tell us about the redistribution of the radionuclide as a result of soil erosion, differential migration through the soil—or its complement, differential retention in the soil. Any such inferences from survey measurements depend on the assumption of a broadly even distribution from weapons testing fallout, and the substantial deposition of 137Cs in rain following the Chernobyl accide...

  4. METHODOLOGY OF INTERNAL DOSE RECONSTRUCTION FOR THE RUSSIAN POPULATION AFTER THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    M. I. Balonov

    2008-01-01

    Full Text Available The paper presents methodology of the internal dose reconstruction from I-131 and caesium radionuclides received by population of Russia after the Chernobyl accident. The direct measurements of radionuclides content in a human body were the most relevant data for internal dose reconstruction. Assessment of radionuclides intake with food products was considered as the second priority and application of radioecological models as the third priority when measurement data were absent.

  5. Effect of natural {beta}-carotene supplementation in children exposed to radiation from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Amotz, A. [Israel Oceanographic and Limnological Research, Haifa (Israel); Yatziv, S. [Pediatric Department, Hadassah University Hospital, Jerusalem (Israel); Sela, M. [Maxillary-Facial Rehabilitation, Hadassah University Hospital, Jerusalem (Israel); Greenberg, S.; Rachmilevich, B.; Shwarzman, M.; Weshler, Z. [Sharett Institute of Oncology, Hadassah University Hospital, Jerusalem (Israel)

    1998-10-01

    Attempts were made to evaluate 709 children (324 boys and 385 girls) who had been exposed long-term to different doses of radiation during and after the Chernobyl accident and had moved to Israel between 1990 and 1994. Upon arrival, all of them underwent a check-up for most common clinical disorders and were then divided into three groups according to their residences (distance from the reactor) and the level of irradiation exposure: no radiation, <5 Ci/m{sup 2}, and >5 Ci/m{sup 2}, respectively. Blood serum analyses for total carotenoids, retinol, {alpha}-tocopherol and oxidized conjugated dienes in 262 of the children showed increased HPLC levels of conjugated dienes, indicating increased levels of oxidation of in vivo blood lipids in children from the contaminated areas. The levels were higher in girls than in boys. Some 57 boys and 42 girls were given a basal diet with a diurnal supplementation of 40 mg natural 9-cis and all-trans equal isomer mixture {beta}-carotene in a capsulated powder form of the alga Dunaliella bardawil, for a period of 3 months. Blood serum analyses were regularly conducted before supplementation to determine the baseline effect of radiation exposure to the children, after 1 and 3 months of natural {beta}-carotene supplementation. After supplementation, the levels of the oxidized conjugated dienes decreased in the children`s sera without any significant changes in the level of total carotenoids, retinol or {alpha}-tocopherol. Other common blood biochemicals were within the normal range for all tests and no statistical differences before or after supplementation of {beta}-carotene were noted. High pressure liquid chromatography (HPLC) analyses for carotenoids in the blood detected mainly oxycarotenoids, and to a lesser extent, all-trans {beta}-carotene, {alpha}-carotene, but not 9-cis {beta}-carotene. The results suggest that irradiation increases the susceptibility of lipids to oxidation in the Chernobyl children and that natural {beta

  6. Comparative modeling analyses of Cs-137 fate in the rivers impacted by Chernobyl and Fukushima accidents

    Energy Technology Data Exchange (ETDEWEB)

    Zheleznyak, M.; Kivva, S. [Institute of Environmental Radioactivity, Fukushima University (Japan)

    2014-07-01

    The consequences of two largest nuclear accidents of the last decades - at Chernobyl Nuclear Power Plant (ChNPP) (1986) and at Fukushima Daiichi NPP (FDNPP) (2011) clearly demonstrated that radioactive contamination of water bodies in vicinity of NPP and on the waterways from it, e.g., river- reservoir water after Chernobyl accident and rivers and coastal marine waters after Fukushima accident, in the both cases have been one of the main sources of the public concerns on the accident consequences. The higher weight of water contamination in public perception of the accidents consequences in comparison with the real fraction of doses via aquatic pathways in comparison with other dose components is a specificity of public perception of environmental contamination. This psychological phenomenon that was confirmed after these accidents provides supplementary arguments that the reliable simulation and prediction of the radionuclide dynamics in water and sediments is important part of the post-accidental radioecological research. The purpose of the research is to use the experience of the modeling activities f conducted for the past more than 25 years within the Chernobyl affected Pripyat River and Dnieper River watershed as also data of the new monitoring studies in Japan of Abukuma River (largest in the region - the watershed area is 5400 km{sup 2}), Kuchibuto River, Uta River, Niita River, Natsui River, Same River, as also of the studies on the specific of the 'water-sediment' {sup 137}Cs exchanges in this area to refine the 1-D model RIVTOX and 2-D model COASTOX for the increasing of the predictive power of the modeling technologies. The results of the modeling studies are applied for more accurate prediction of water/sediment radionuclide contamination of rivers and reservoirs in the Fukushima Prefecture and for the comparative analyses of the efficiency of the of the post -accidental measures to diminish the contamination of the water bodies. Document

  7. The Chernobyl accident: EPR dosimetry on dental enamel of children

    Energy Technology Data Exchange (ETDEWEB)

    Gualtieri, G. E-mail: gianni@fismedw2.univaq.it; Colacicchi, S.; Sgattoni, R.; Giannoni, M

    2001-07-01

    The radiation dose on tooth enamel of children living close to Chernobyl has been evaluated by EPR. The sample preparation was reduced to a minimum of mechanical steps to remove a piece of enamel. A standard X-ray tube at low energy was used for additive irradiation. The filtration effect of facial soft tissue was taken into account. The radiation dose for a group of teeth slightly exceeds the annual dose, whereas for another group the dose very much exceeds the annual dose. Since the higher dose is found in teeth whose enamel have much lower EPR sensitivity to the radiation, it can be suggested that for these teeth the native signal could alter the evaluation of the smaller radiation signal.

  8. The Chernobyl accident: EPR dosimetry on dental enamel of children.

    Science.gov (United States)

    Gualtieri, G; Colacicchi, S; Sgattoni, R; Giannoni, M

    2001-07-01

    The radiation dose on tooth enamel of children living close to Chernobyl has been evaluated by EPR. The sample preparation was reduced to a minimum of mechanical steps to remove a piece of enamel. A standard X-ray tube at low energy was used for additive irradiation. The filtration effect of facial soft tissue was taken into account. The radiation dose for a group of teeth slightly exceeds the annual dose, whereas for another group the dose very much exceeds the annual dose. Since the higher dose is found in teeth whose enamel have much lower EPR sensitivity to the radiation, it can be suggested that for these teeth the native signal could alter the evaluation of the smaller radiation signal.

  9. Reactor accidents and the actions of fire brigades. Plea for nuclear phaseout. An analytic report on Leipzig, Windscale, Chernobyl and Fukushima; Reaktorunfaelle und die Handlungen der Feuerwehr. Plaedoyer fuer den Atomausstieg. Ein Analysebericht zu Leipzig, Windscale, Tschernobyl und Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Steffler, Reinhard

    2016-11-01

    The report covers the historically first fire brigade action at the ''uranium machine'' on June 23th 1942 in Leipzig, and the fire brigade actions in Windscale (October 11, 1957), Chernobyl and Fukushima Daiichi. Further issues are the behavior of the media, selected features of the fire brigade actions, and a discussion of questions concerning the preparedness of the fire brigades.

  10. Contaminants in food chains of arctic ungulates: what have we learned from the Chernobyl accident?

    Directory of Open Access Journals (Sweden)

    Birgitta Åhman

    1998-03-01

    Full Text Available The Chernobyl accidenr of 1986 caused radioactive contamination of widespread areas of reindeer pasture in Scandinavia. Reindeer {Rangifer tarandus are especially exposed to radioactive fallout due to their wintet diet, of which lichens are an important part. Much knowledge about the transfer of radiocaesium to reindeer, and via reindeer meat to man, was accumulated by intense scientific investigations, undertaken during the 1960s and 1970s, following nuclear weapons testing. Various ways to reduce the transfer of radiocaesium to animals and humans were also developed during this time. Much of the older knowledge proved to be of great value in the attempts to determine potential consequences of the Chernobyl accident and to suggest possible ways to ameliorate the effects of contamination. After Chernobyl, not only did reindeer prove to be a problem; many other food products originating ftom natural and semi-natural ecosystems were found to accumulate significant amounts of radiocaesium. Intense scientific work has produced new knowledge about the role of ungulates in the transfer of nutrients and contaminants within these systems. Different measures, like providing uncontaminated feed, use of caesium binders, altering the time of slaughter have been used with good results to minimize the transfer of radiocaesium to animals grazing natural pastures. The high cost of countermeasures has enforced consideration of cost against risk, which may also be of general interest with respect to other forms of pollution. Information, introduction of countermeasures and so forth would be more efficient in case a similar accident were to happen again. The Chernobyl accident is an obvious example of how human failures when dealing with a modern technical system can have global consequences and also be a potential threat to what we like to think of as the unspoiled wilderness of the Arctic.

  11. Evaluation of the long-rang dispersion of radionuclides from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Suh, K.S.; Jeong, H.J.; Kim, E.H.; Hwang, W.T.; Han, M.H. [Korea Atomic Energy Research Institute (KAERI), Nuclear Environmental Research Div., Daejeon (Korea, Republic of)

    2006-07-01

    The atmospheric dispersion models have been developed to predict and minimize the radiological damage for the surrounding environment since the Chernobyl accident. There are many nuclear power plants in the region of Northeast Asia. It is necessary to develop a long-range atmospheric dispersion model for the radiological emergency preparedness against a nuclear accident. From this viewpoint, a Lagrangian particle model named L.A.D.A.S.(Long-range Accident Dose Assessment System) was initially developed for the evaluation the long-range dispersion in Korea since 2001. The model designed to estimate air concentrations and dry deposition as well as wet deposition at distances up to some thousands of kilometers from the source point in a horizontal direction. The validation study of the model was firstly performed by comparing the measured values of E.T.E.X. exercise. The developed model was also applied to simulate the movements of the radioactive materials at the Chernobyl accident. An intercomparison and validation study among the long-range models was performed through the A.T.M.E.S.(Atmospheric Transport Model Evaluation Study) project under auspices of the IAEA/W.M.O. (world meteorological organization) in 1992. As a consequence of A.T.M.E.S., it was observed that in a real emergency case, under conditions of urgency and stress, many of the models would have had different results. So, one of the main recommendations was the launch of a long-range atmospheric tracer experiment in conditions as close as possible to those which could be found in a real emergency case, with the advantage of a complete knowledge of the source term. In this study, numerical simulations were carried out to estimate the concentration distributions of {sup 137}Cs. The calculated results agreed well with them by Chernobyl accident. In conclusion, a three dimensional Lagrangian particle model named L.A.D.A.S. was developed to evaluate the characteristics of a long-range atmospheric

  12. Mechanical decontamination tests in areas affected by the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Roed, J.; Andersson, K.G.; Barkovsky, A.N.; Fogh, C.L.; Mishine, A.S.; Olsen, S.K.; Ponamarjov, A.V.; Prip, H.; Ramzaev, V.P.; Vorobiev, B.F

    1998-08-01

    Decontamination was carried out around three houses in Novo Bobovichi, Russia, in the summer of 1997. It was demonstrated that significant reductions in the dose rate both indoor (DRF = 0.27) and outdoor (DRF = 0.17) can be achieved when a careful cleaning is undertaken. This report describes the decontamination work carried out and the results obtained. The roof of one of the houses was replaced with a new roof. This reduced the Chernobyl related dose rate by 10% at the ground floor and by 27% at the first floor. The soil around the houses was removed by a bobcat, while carefully monitoring the ground for residual contamination with handheld dose meters. By monitoring the decline in the dose rate during the different stages of the work the dose reducing effect of each action has been estimated. This report also describes a test of a skim-and-burial plough developed especially for treatment of contaminated land. In the appendices of the report the measurement data is available for further analysis. (au) 24 tabs., 75 ills., 33 refs.

  13. THE EVALUATION OF VORONEZH REGION RADIATION CONTAMINATION IMPACT OVER THIRTY YEARS’ PERIOD FOLLOWING THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    Yu. I. Stepkin

    2016-01-01

    Full Text Available The study aimed at radiation contamination impact assessment due to the 1986 Chernobyl accident in Voronezh Region territory more than 600 kilometers away from the ground zero. The major Chernobyl accident impact assessment indicators were the characteristics of 137Cs and 90Sr radionuclides’ soil surface contamination (Ci/km2 as well as the average annual effective dose of critical population group ( mSv/year over 1986–2014. The Population oncological morbidity indicators were analyzed (all malignant neoplasms, including those in thyroid gland, lymphatic and hematopoietic tissue in the territories contrastingly differing on the levels of radiation factor impact. The study covered the period of 2010–2014.It was established that for Voronezh Region territories referred to as the post- Chernobyl radioactively contaminated zone over 29 years period the maximum soil surface contamination by 137Cs and 90Sr radionuclides reduced by 1.90 and 1.91 times (from 3,15 Ci/km2 to 1,66 Ci/km2 and from 0,063 Ci/km2 to 0,0033 Ci/km2, respectively.Currently the relationship was not found between the radioactive contamination density in Voronezh Region and the levels of malignant neoplasms for the local residents.The present situation related to radiation factor impact on Voronezh Region territories remains stable and safe. Mindful of the indicators results the assessment of ionizing sources impact did not identify any exceeding the normative values.

  14. Radioecological and dosimetric consequences of Chernobyl accident in France; Consequences radioecologiques et dosimetriques de l`accident de Tchernobyl en France

    Energy Technology Data Exchange (ETDEWEB)

    Renaud, Ph.; Beaugelin, K.; Maubert, H.; Ledenvic, Ph

    1997-12-31

    After ten years and the taking in account of numerous data, it can be affirmed that the dosimetric consequences of Chernobyl accident will have been limited in France. for the period 1986-2046, the individual middle efficient dose commitment, for the area the most reached by depositing is inferior to 1500 {mu}Sv, that represents about 1% of middle natural exposure in the same time. but mountains and forests can have more important surface activities than in plain. Everywhere else, it can be considered that the effects of Chernobyl accident are disappearing. the levels of cesium 137 are now often inferior to what they were before the accident. (N.C.)

  15. Radiation Exposure and Thyroid Cancer Risk After the Fukushima Nuclear Power Plant Accident in Comparison with the Chernobyl Accident.

    Science.gov (United States)

    Yamashita, S; Takamura, N; Ohtsuru, A; Suzuki, S

    2016-09-01

    The actual implementation of the epidemiological study on human health risk from low dose and low-dose rate radiation exposure and the comprehensive long-term radiation health effects survey are important especially after radiological and nuclear accidents because of public fear and concern about the long-term health effects of low-dose radiation exposure have increased considerably. Since the Great East Japan earthquake and the Fukushima Daiichi Nuclear Power Plant accident in Japan, Fukushima Prefecture has started the Fukushima Health Management Survey Project for the purpose of long-term health care administration and medical early diagnosis/treatment for the prefectural residents. Especially on a basis of the lessons learned from the Chernobyl accident, both thyroid examination and mental health care are critically important irrespective of the level of radiation exposure. There are considerable differences between Chernobyl and Fukushima regarding radiation dose to the public, and it is very difficult to estimate retrospectively internal exposure dose from the short-lived radioactive iodines. Therefore, the necessity of thyroid ultrasound examination in Fukushima and the intermediate results of this survey targeting children will be reviewed and discussed in order to avoid any misunderstanding or misinterpretation of the high detection rate of childhood thyroid cancer.

  16. Distribution of radionuclides in the environment in Northern Italy after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Berzero, A. (Pavia Univ. (Italy). Lab. Energia Nucleare Applicata); Borroni, P.A.; Oddone, M. (Pavia Univ. (Italy). Dip. di Chimica Generale); Crespi, V.C.; Genova, N.; Meloni, S. (Consiglio Nazionale delle Ricerche, Pavia (Italy). Centro di Radiochimica ed Analisi per Attivazione)

    1992-03-01

    Soon after the Chernobyl nuclear accident, the air-pumping stations in Pavia (northern Italy) were alerted. In a few days, a rapid increase in radionuclide concentration in air particulates was observed. Consequently, an environmental radioactivity monitoring programme was started in which several matrices such as soil, grass, vegetables and cows' milk were subjected to direct gamma-ray spectrometry. The radioactivity distribution and its variation with time is presented, discussed and compared with other available data. Detection limits, precision and accuracy are also reported, and depth profiles in soils for {sup 137}Cs are presented and correlated with soil quality parameters. A survey of environmental radioactivity in soil, in a search for residual Chernobyl fallout, was carried out and a map of the {sup 137}Cs distribution over a large area in northern Italy is presented and discussed. (author).

  17. Post-Chernobyl accident radioactivity measurements in the Comunidad Autonoma de Valencia, Spain.

    Science.gov (United States)

    Ortiz, J; Ballesteros, L; Serradell, V

    1992-03-01

    Increased atmospheric radioactivity after the accident in Chernobyl was first detected on air filters. Measurements were begun in Valencia on May 2, 1986, with the maximum activity being observed around May 3-4, 1986. As a consequence of this accident, annual campaigns of measurements on migrating birds (several species of aquatic birds and song-thrushes) were started. The data corresponding to the campaign immediately after the accident (1986/87) show a generalized contamination (approximately 50% of the measured specimens). Significant levels of 134Cs, 137Cs and 110Agm were found. It is important to note that 110Agm is only present in Aythya ferina. In the successive campaigns in 1988/89 and 1989/91 few samples were found to be contaminated and only 137Cs was identified. Strontium-90 was measured and identified in some specimens, mainly in their bones.

  18. Radioactivity measurements in air over Europe after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Raes, F.; Graziani, G.; Stanners, D.; Girardi, F. (Commission of the European Communities, Ispra (Italy). Joint Research Centre)

    1990-01-01

    A comprehensive European data set of radioactivity in air caused by the accident at the Chenobyl nuclear power plant is presented. For the first 2 weeks after the beginning of the release, levels of particulate I-131, Cs-134 and Cs-137 (85 locations) and of total I-131 (10 locations) are given. All data are stored in a computerized data base. For the first time the passage of the Chenobyl cloud over Europe is mapped after re-averaging the time histories in each location to produce coherent daily concentrations. Cs-134/Cs-137 ratios were analysed: the 'European' average ratio calculated from 1239 samples is 0.55, with a standard deviation of 0.25. (author).

  19. The monitoring of herbaceous seeds in the 30-km zone of the Chernobyl nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Taskaev, A.I.; Frolova, N.P.; Popova, O.N.; Shevchenko, V.A. (AN SSSR, Syktyvkar (Russian Federation). Komi Filial AN SSSR, Moscow (Russian Federation). Inst. Obshchej Genetiki)

    1992-02-01

    Species of wild herbaceous plants growing over a period of 3 years under chronic irradiation resulting from the Chernobyl accident were studied. Examining the mass of 1000 seeds and their germination did not yield any significant differences between groups of seeds of the same species collected from the different contaminated zones. Nor did the frequency of aberrant cells in roots of germinated seeds reveal any significant differences between the zones. Seeds of Plantago lanceolata growing in areas with higher levels of radiation, did appear to be more sensitive to additional gamma-irradiation. (author). 5 refs.; 7 figs.; 5 tabs.

  20. RADIATION CONDITIONS IN KALUGA REGION 30 YEARS AFTER CHERNOBYL NPP ACCIDENT

    Directory of Open Access Journals (Sweden)

    A. G. Ashitko

    2016-01-01

    Full Text Available The article describes radiation conditions in the Kaluga region 30 years after the Chernobyl NPP accident. The Chernobyl NPP accident caused radioactive contamination of nine Kaluga region territories: Duminichsky, Zhizdrinsky, Kuibyshevsky, Kirovsky, Kozelsky, Ludinovsky, Meshchovsky, Ulyanovsky and Hvastovichsky districts. Radioactive fallout was the strongest in three southern districts: Zhizdrinsky, Ulyanovsky and Hvastovichsky, over there cesium-137 contamination density is from 1 to 15Ci/km. According to the Russian Federation Government Order in 2015 there are 300 settlements (S in the radioactive contamination zone, including 14 settlements with caesium-137 soil contamination density from 5 to 15 Ci/ km2 and 286 settlements with the contamination density ranging from 1 to 5 Ci/km2. In the first years after the Chernobyl NPP accident in Kaluga region territories, contaminated with caesium-137, there were introduced restrictive land usage, were carried out agrochemical activities (ploughing, mineral fertilizer dressing, there was toughened laboratory radiation control over the main doze-forming foodstuff. All these measures facilitated considerable decrease of caesium-137 content in local agricultural produce. Proceeding from the achieved result, in 2002 there took place the transition to more tough requirements SanPiN 2.3.2.1078-01. Analysis of investigated samples from Zhizdrinsky, Ulyanovsky and Hvastovichsky districts demonstrated that since 2005 meat samples didn’t exceed the standard values, same for milk samples since 2007. Till the present time, the use of wild-growing mushrooms, berries and wild animals meat involves radiation issues. It was demonstrated that average specific activity of caesium-137 in milk samples keeps decreasing year after year. Long after the Chernobyl NPP accident, the main products forming internal irradiation doses in population are the wild-growing mushrooms and berries. Population average annual

  1. Chernobyl and Fukushima nuclear accidents: what has changed in the use of atmospheric dispersion modeling?

    Science.gov (United States)

    Benamrane, Y; Wybo, J-L; Armand, P

    2013-12-01

    The threat of a major accidental or deliberate event that would lead to hazardous materials emission in the atmosphere is a great cause of concern to societies. This is due to the potential large scale of casualties and damages that could result from the release of explosive, flammable or toxic gases from industrial plants or transport accidents, radioactive material from nuclear power plants (NPPs), and chemical, biological, radiological or nuclear (CBRN) terrorist attacks. In order to respond efficiently to such events, emergency services and authorities resort to appropriate planning and organizational patterns. This paper focuses on the use of atmospheric dispersion modeling (ADM) as a support tool for emergency planning and response, to assess the propagation of the hazardous cloud and thereby, take adequate counter measures. This paper intends to illustrate the noticeable evolution in the operational use of ADM tools over 25 y and especially in emergency situations. This study is based on data available in scientific publications and exemplified using the two most severe nuclear accidents: Chernobyl (1986) and Fukushima (2011). It appears that during the Chernobyl accident, ADM were used few days after the beginning of the accident mainly in a diagnosis approach trying to reconstruct what happened, whereas 25 y later, ADM was also used during the first days and weeks of the Fukushima accident to anticipate the potentially threatened areas. We argue that the recent developments in ADM tools play an increasing role in emergencies and crises management, by supporting stakeholders in anticipating, monitoring and assessing post-event damages. However, despite technological evolutions, its prognostic and diagnostic use in emergency situations still arise many issues.

  2. "What--me worry?" "Why so serious?": a personal view on the Fukushima nuclear reactor accidents.

    Science.gov (United States)

    Gallucci, Raymond

    2012-09-01

    Infrequently, it seems that a significant accident precursor or, worse, an actual accident, involving a commercial nuclear power reactor occurs to remind us of the need to reexamine the safety of this important electrical power technology from a risk perspective. Twenty-five years since the major core damage accident at Chernobyl in the Ukraine, the Fukushima reactor complex in Japan experienced multiple core damages as a result of an earthquake-induced tsunami beyond either the earthquake or tsunami design basis for the site. Although the tsunami itself killed tens of thousands of people and left the area devastated and virtually uninhabitable, much concern still arose from the potential radioactive releases from the damaged reactors, even though there was little population left in the area to be affected. As a lifelong probabilistic safety analyst in nuclear engineering, even I must admit to a recurrence of the doubt regarding nuclear power safety after Fukushima that I had experienced after Three Mile Island and Chernobyl. This article is my attempt to "recover" my personal perspective on acceptable risk by examining both the domestic and worldwide history of commercial nuclear power plant accidents and attempting to quantify the risk in terms of the frequency of core damage that one might glean from a review of operational history.

  3. Consequences to health of the Chernobyl accident; Helbredsmaessige konsekvenser af reaktorulykken i Tjernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Sewerin, I. [Royal Dental College, Dept. of Radiology, Copenhagen (Denmark)

    2001-07-01

    The Chernobyl accident in 1986 has been and still is the subject of great interest. Journalistic reports often contain exaggerations and undocumented statements and much uncertainty about the true consequences of the accident prevails in the population. This article reviews the current literature with the focus on reports from official commissions and documentation in the form of controlled studies. The fatal deterministic consequences comprise about 30 victims. The most important outcome is a marked increase in the incidence of thyroid cancer in children and adolescents in the most heavily contaminated area. Furthermore, pronounced psychosocial problems are dominant in the population of the contaminated area. Other significant and documented health consequences are not seen. (au)

  4. Mesoscale modelling of radioactive contamination formation in Ukraine caused by the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Talerko, Nikolai [Scientific Center for Radiation Medicine, 53 Melnikov Street, Kyiv 04050 (Ukraine)]. E-mail: nick@rpi.kiev.ua

    2005-03-01

    This work is devoted to the reconstruction of time-dependent radioactive contamination fields in the territory of Ukraine in the initial period of the Chernobyl accident using the model of atmospheric transport LEDI (Lagrangian-Eulerian DIffusion model). The modelling results were compared with available {sup 137}Cs air and ground contamination measurement data. The {sup 137}Cs atmospheric transport over the territory of Ukraine was simulated during the first 12 days after the accident (from 26 April to 7 May 1986) using real aerological information and rain measurement network data. The detailed scenario of the release from the accidental unit of the Chernobyl nuclear plant has been built (including time-dependent radioactivity release intensity and time-varied height of the release). The calculations have enabled to explain the main features of spatial and temporal variations of radioactive contamination fields over the territory of Ukraine on the regional scale, including the formation of the major large-scale spots of radioactive contamination caused by dry and wet deposition.

  5. Caesium 137 in northern Swedish moose: The first year after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Danell, K.; Nelin, P. (Swedish Univ. of Agricultural Science, Umeaa (Sweden). Dept. of Wildlife Ecology); Wickman, G. (Umeaa Univ. (Sweden). Radiation Physics Dept.)

    1989-01-01

    Levels of /sup 137/ caesium were monitored in northern Sweden during the first year after the Chernobyl accident (April 1986). Samples were collected from 3661 moose in an area where the deposited /sup 137/ caesium ranged from two to 60 kilo-becquerel per m/sup 2/. Concentrations of caesium in moose muscle correlated positively with the ground deposition of caesium. On average, the caesium levels found in moose after Chernobyl were about 470 Bq per kg fresh mass for calves and close to 300 for older animals. The average level in moose before the accident was 33 Bq per kg. Among moose older than one year, higher concentrations were found in females than in the males. There was a pronounced seasonal variation in the /sup 137/ caesium concentration found in moose. Within the investigation area the presence of caesium in moose resulted in a minor proportion of the hunters discarding the animals shot and/or terminating the hunt before the end of the season.

  6. [Genetic effects in populations of plants growing in the zone of Kyshtym and Chernobyl accidents].

    Science.gov (United States)

    Shevchenko, V A; Kal'chenko, V A; Abramov, V I; Rubanovich, A V; Shevchenko, V V; Grinikh, L I

    1999-01-01

    Studies to analyze the genetic processes in natural populations of plants were started on the territory of the East-Ural Radioactive Trace (EURT) in 1962 and in the zone of the Chernobyl accident in May 1986. The main directions of the genetic studies in both radioactive areas were similar: 1) study of the mutation process intensity depending on the dose and dose rate and analysis of dose-effect relationships for different genetic changes (point mutations, chromosome aberrations in mitosis and meiosis) in irradiated plant populations; 2) study of the mutation process dynamics in generations of chronically (prolongly) irradiated populations of plants; 3) analysis of microevolutionary processes in irradiated plant populations. The report presents an analysis of observed dose-effect relationships under the action of radiation on populations of Arabidopsis thaliana, Pinus sylvestris and a number of other plant species. Analysis of the mutation processes dynamics in 8 Arabidopsis populations growing in the zone of the Chernobyl catastrophe has demonstrated that the level of the embryo lethal mutations 10 years after the accident in the irradiated populations significantly exceeds the control level. The following phenomena observed in chronically irradiated populations have also been considered: increased radioresistance of irradiated populations (radioadaptation), the appearance of abnormal karyotypes and selective markers upon chronic irradiation. The authors call attention to the high importance of monitoring of genetic processes in irradiated plant populations for understanding of the action of radiation on human populations.

  7. Potassium iodide for thyroid blockade in a reactor accident: administrative policies that govern its use.

    Science.gov (United States)

    Becker, D V; Zanzonico, P

    1997-04-01

    A marked increase in thyroid cancer among young children who were in the vicinity of the Chernobyl nuclear power plant at the time of the 1986 accident strongly suggests a possible causal relationship to the large amounts of radioactive iodine isotopes in the resulting fallout. Although remaining indoors, restricting consumption of locally produced milk and foodstuffs, and evacuation are important strategies in a major breach-of-containment accident, stable potassium iodide (KI) prophylaxis given shortly before or immediately after exposure can reduce greatly the thyroidal accumulation of radioiodines and the resulting radiation dose. Concerns about possible side effects of large-scale, medically unsupervised KI consumption largely have been allayed in light of the favorable experience in Poland following the Chernobyl accident; 16 million persons received single administrations of KI with only rare occurrence of side effects and with a probable 40% reduction in projected thyroid radiation dose. Despite the universal acceptance of KI as an effective thyroid protective agent, supplies of KI in the US are not available for public distribution in the event of a reactor accident largely because government agencies have argued that stockpiling and distribution of KI to other than emergency workers cannot be recommended in light of difficult distribution logistics, problematic administrative issue, and a calculated low cost-effectiveness. However, KI in tablet form is expensive and has a long shelf life, and many countries have largely stockpiles and distribution programs. The World Health Organization recognizes the benefits of stable KI and urges its general availability. At present there are 110 operating nuclear power plants in the US and more than 300 in the rest of the world. These reactors product 17% of the world's electricity and in some countries up to 60-70% of the total electrical energy. Almost all US nuclear power plants have multistage containment

  8. Cancer incidence in northern Sweden before and after the Chernobyl nuclear power plant accident.

    Science.gov (United States)

    Alinaghizadeh, Hassan; Tondel, Martin; Walinder, Robert

    2014-08-01

    Sweden received about 5 % of the total release of (137)Cs from the Chernobyl nuclear power plant accident in 1986. The distribution of the fallout mainly affected northern Sweden, where some parts of the population could have received an estimated annual effective dose of 1-2 mSv per year. It is disputed whether an increased incidence of cancer can be detected in epidemiological studies after the Chernobyl nuclear power plant accident outside the former Union of Soviet Socialist Republics. In the present paper, a possible exposure-response pattern between deposition of (137)Cs and cancer incidence after the Chernobyl nuclear power plant accident was investigated in the nine northernmost counties of Sweden (2.2 million inhabitants in 1986). The activity of (137)Cs from the fallout maps at 1986 was used as a proxy for the received dose of ionizing radiation. Diagnoses of cancer (ICD-7 code 140-209) from 1980 to 2009 were received from the Swedish Cancer Registry (273,222 cases). Age-adjusted incidence rate ratios, stratified by gender, were calculated with Poisson regression in two closed cohorts of the population in the nine counties 1980 and 1986, respectively. The follow-up periods were 1980-1985 and 1986-2009, respectively. The average surface-weighted deposition of (137)Cs at three geographical levels; county (n = 9), municipality (n = 95) and parish level (n = 612) was applied for the two cohorts to study the pre- and the post-Chernobyl periods separately. To analyze time trends, the age-standardized total cancer incidence was calculated for the general Swedish population and the population in the nine counties. Joinpoint regression was used to compare the average annual percent change in the general population and the study population within each gender. No obvious exposure-response pattern was seen in the age-adjusted total cancer incidence rate ratios. A spurious association between fallout and cancer incidence was present, where areas with the

  9. The Chernobyl accident consequences; Consequences de l'accident de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-04-01

    Five teen years later, Tchernobyl remains the symbol of the greater industrial nuclear accident. To take stock on this accident, this paper proposes a chronology of the events and presents the opinion of many international and national organizations. It provides also web sites references concerning the environmental and sanitary consequences of the Tchernobyl accident, the economic actions and propositions for the nuclear safety improvement in the East Europe. (A.L.B.)

  10. Impact of Uncertainties in Exposure Assessment on Thyroid Cancer Risk among Persons in Belarus Exposed as Children or Adolescents Due to the Chernobyl Accident.

    Directory of Open Access Journals (Sweden)

    Mark P Little

    Full Text Available The excess incidence of thyroid cancer in Ukraine and Belarus observed a few years after the Chernobyl accident is considered to be largely the result of 131I released from the reactor. Although the Belarus thyroid cancer prevalence data has been previously analyzed, no account was taken of dose measurement error.We examined dose-response patterns in a thyroid screening prevalence cohort of 11,732 persons aged under 18 at the time of the accident, diagnosed during 1996-2004, who had direct thyroid 131I activity measurement, and were resident in the most radio-actively contaminated regions of Belarus. Three methods of dose-error correction (regression calibration, Monte Carlo maximum likelihood, Bayesian Markov Chain Monte Carlo were applied.There was a statistically significant (p0.2.In summary, the relatively small contribution of unshared classical dose error in the current study results in comparatively modest effects on the regression parameters.

  11. Analysis of Credible Accidents for Argonaut Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hawley, S. C.; Kathern, R. L.; Robkin, M. A.

    1981-04-01

    Five areas of potential accidents have been evaluated for the Argonaut-UTR reactors. They are: • insertion of excess reactivity • catastrophic rearrangement of the core • explosive chemical reaction • graphite fire • fuel-handling accident. A nuclear excursion resulting from the rapid insertion of the maximum available excess reactivity would produce only 12 MWs which is insufficient to cause fuel melting even with conservative assumptions. Although precise structural rearrangement of the core would create a potential hazard, it is simply not credible to assume that such an arrangement would result from the forces of an earthquake or other catastrophic event. Even damage to the fuel from falling debris or other objects is unlikely given the normal reactor structure. An explosion from a metal-water reaction could not occur because there is no credible source of sufficient energy to initiate the reaction. A graphite fire could conceivably create some damage to the reactor but not enough to melt any fuel or initiate a metal-water reaction. The only credible accident involving offsite doses was determined to be a fuel-handling accident which, given highly conservative assumptions, would produce a whole-body dose equivalent of 2 rem from noble gas immersion and a lifetime dose equivalent commitment to the thyroid of 43 rem from radioiodines.

  12. Countermeasures to the Chernobyl accident in the Nordic countries: Public reactions

    Energy Technology Data Exchange (ETDEWEB)

    Sjoeberg, L.; Rundmo, T.; Eraenen, L.; Ekstroem, H

    1998-01-01

    In Sweden the TMI accident was the direct cause to a decision to hold a national referendum on nuclear power on March 23, 1980. The referendum and the subsequent political decision to phase out nuclear power by 2010 to some extent neutralized the issue and nuclear attitudes returned to a mildly positive state. However, the Chernobyl accident in 1986 again changed the scene. Just as the TMI accident had been something of a surprise to many, the Chernobyl accident and its consequences in Scandinavia were not anticipated. Attitudes to nuclear power became quite negative immediately after the accident but they soon resumed their initial mildly positive position again. Even if the radioactive fall-out never reached truly alarming levels authorities in Finland, Norway and Sweden took measures to counteract the effects of radioactivity and to protect the population. This was done in a very heated atmosphere and intense attention was paid by the mass media. Trust in authorities and governments was put to a stringent test during these days 10 years ago. Several psychologists, sociologists and mass media researchers were active from the very beginning to document the events taking place, e.g. by means of surveys of the public opinion. The reports they wrote were usually in local languages and much of this material was never published in print but remained as project reports. It is the purpose of the present project to localize these report and to summarize and interpret their contents, and to give bibliographical information about where the sources can be located. Different experiences and conditions in the three countries account for somewhat different approaches of the three country chapters. There is no doubt that Chernobyl was a very significant social and psychological event in the three countries discussed in the present report. It was also regarded by many as a significant threat to public health, although radiation experts assured the public that the direct effects

  13. Strontium-90 concentrations in human teeth in south Ukraine, 5 years after the Chernobyl accident.

    Science.gov (United States)

    Kulev, Y D; Polikarpov, G G; Prigodey, E V; Assimakopoulos, P A

    1994-10-28

    Approximately 1000 human teeth, collected in South Ukraine, in 1990-1991, were measured for 90Sr concentration. The teeth were grouped into 18 samples according to the age and sex of the donors. Measured levels of 90Sr concentrations were lower by a factor of 10 than measurements taken in the mid-1960s and mid-1970s. An interesting feature of the data is a 3-fold enhancement of contamination levels in the 25-45 year-old age group of the male population. A possible explanation for this anomaly is that this age group contains a significant number of men who were mobilized immediately after the Chernobyl accident for clean-up operations within the 30-km zone around the damaged nuclear power plant.

  14. Perceived risks and risk attitudes in southern Russia in the aftermath of the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Drottz-Sjoeberg, B.M. [Stockholm School of Economics (Sweden). Center for Risk Research; Rumyantseva, G.M.; Martyvshov, A.N. [The Serbsky Research Institute, Moscow, (Russian Federation)

    1993-10-01

    The present study was conducted within the framework of the Joint Study Project 2 (JSP2), a research project involving the European Community and the Commonwealth of Independent States. The task involved the investigation of public reactions to radioactive contamination due to the Chernobyl accident in 1986. The here presented field-work was designed as a pilot investigation in a series of studies aimed at contributing to the understanding of social and psychological factors relevant to the design of countermeasures in the case of a future nuclear accident. The report presents questionnaire data collected from people living in Novozybkov and its surroundings in Russia, in the summer of 1992. The chosen areas had an overall surface contamination level of 15-40 Ci/km{sup 2}. The results showed that the respondents recalled the date of the accident surprisingly well. They often indicated that they had heard the first news of the accident via TV, radio or rumors. They often reported the content of that information to have been related to an explosion or a fire at a nuclear plant. They indicated that they at the time had a rather modest reaction to the news. Current worries especially concerned health risks due to the radioactive contamination, although the respondents also emphasized that ordinary life was filled with worries. Middle-aged persons and parents often indicated the highest personal worry. Risk ratings related to radiation and radioactive contamination were high. Ratings of perceived change in risk level since the accident of a variety of hazards showed an overall increase. 27 refs, 23 figs, 23 tabs.

  15. Modelling transport and deposition of caesium and iodine from the Chernobyl accident using the DREAM model

    Directory of Open Access Journals (Sweden)

    J. Brandt

    2002-01-01

    Full Text Available A tracer model, DREAM (the Danish Rimpuff and Eulerian Accidental release Model, has been developed for modelling transport, dispersion and deposition (wet and dry of radioactive material from accidental releases, as the Chernobyl accident. The model is a combination of a Lagrangian model, that includes the near source dispersion, and an Eulerian model describing the long-range transport. The performance of the transport model has previously been tested within the European Tracer Experiment, ETEX, which included transport and dispersion of an inert, non-depositing tracer from a controlled release. The focus of this paper is the model performance with respect to the total deposition of  137Cs, 134Cs and 131I from the Chernobyl accident, using different relatively simple and comprehensive parameterizations for dry- and wet deposition. The performance, compared to measurements, of using different combinations of two different wet deposition parameterizations and three different parameterizations of dry deposition has been evaluated, using different statistical tests. The best model performance, compared to measurements, is obtained when parameterizing the total deposition combined of a simple method for dry deposition and a subgrid-scale averaging scheme for wet deposition based on relative humidities. The same major conclusion is obtained for all the three different radioactive isotopes and using two different deposition measurement databases. Large differences are seen in the results obtained by using the two different parameterizations of wet deposition based on precipitation rates and relative humidities, respectively. The parameterization based on subgrid-scale averaging is, in all cases, performing better than the parameterization based on precipitation rates. This indicates that the in-cloud scavenging process is more important than the below cloud scavenging process for the submicron particles and that the precipitation rates are

  16. A 25 year retrospective review of the psychological consequences of the Chernobyl accident.

    Science.gov (United States)

    Bromet, E J; Havenaar, J M; Guey, L T

    2011-05-01

    The Chernobyl Forum Report from the 20th anniversary of the Chernobyl nuclear power plant disaster concluded that mental health effects were the most significant public health consequence of the accident. This paper provides an updated review of research on the psychological impact of the accident during the 25 year period since the catastrophe began. First responders and clean-up workers had the greatest exposure to radiation. Recent studies show that their rates of depression and post-traumatic stress disorder remain elevated two decades later. Very young children and those in utero who lived near the plant when it exploded or in severely contaminated areas have been the subject of considerable research, but the findings are inconsistent. Recent studies of prenatally exposed children conducted in Kiev, Norway and Finland point to specific neuropsychological and psychological impairments associated with radiation exposure, whereas other studies found no significant cognitive or mental health effects in exposed children grown up. General population studies report increased rates of poor self-rated health as well as clinical and subclinical depression, anxiety, and post-traumatic stress disorder. Mothers of young children exposed to the disaster remain a high-risk group for these conditions, primarily due to lingering worries about the adverse health effects on their families. Thus, long-term mental health consequences continue to be a concern. The unmet need for mental health care in affected regions remains an important public health challenge 25 years later. Future research is needed that combines physical and mental health outcome measures to complete the clinical picture.

  17. Radiocaesium Activity Concentrations in Potatoes in Croatia after the Chernobyl Accident and Dose Assessment

    CERN Document Server

    Franic, Z; Marovic, G; Petrinec, B

    2007-01-01

    Systematic investigations of 137Cs and 134Cs activity concentrations in potatoes (Solanum tuberosum) for the post-Chernobyl period (1986-2005) in the Republic of Croatia are summarized. The correlation between 137Cs activity concentrations in fallout and potatoes, has been found to be very good, the correlation coefficient being r2=0.88 with P(t) < 0.001 for 18 degrees of freedom. As the radiocaesium levels in potatoes decreased exponentially, the mean residence time of 137Cs in potatoes was estimated by fitting the measured activity concentrations to the exponential curve. The mean residence time was found to be 6.8 +/- 1.1 years, the standard deviation being estimated by the Monte Carlo simulations. The initial observed 134Cs:137Cs activity ratio in potatoes has been found to be quite variable, but slightly lesser than theoretically predicted value of 0.5, calculated by applying the known inventory of these radionuclides in the Chernobyl reactor to the equation for the differential radioactive decay. Thi...

  18. EXPERIENCE OF RADIATION-HYGIENIC MONITORING MANAGEMENT AND ASSESSMENT OF RADIATION SITUATION IN THE BRYANSK REGION TERRITORY AFTER 25 YEARS SINCE THE DAY OF THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    L. N. Trapeznikova

    2011-01-01

    Full Text Available The article briefly presents the experience of the radiation-hygienic monitoring system creation in the territory contaminated with the radionuclides due to the Chernobyl accident and application of the radiation hygienic monitoring data for the assessment of protective measures efficiency. Radiation situation data for the territory of the Bryansk region after 25 years of Chernobyl accident and dynamics of the population average annual effective exposure dose are being presented.

  19. Radiation-epidemiological Study of Cerebrovascular Diseases in the Cohort of Russian Recovery Operation Workers of the Chernobyl Accident.

    Science.gov (United States)

    Kashcheev, V V; Chekin, S Yu; Maksioutov, M A; Tumanov, K A; Menyaylo, A N; Kochergina, E V; Kashcheeva, P V; Gorsky, A I; Shchukina, N V; Karpenko, S V; Ivanov, V K

    2016-08-01

    The paper presents an analysis of the incidence of cerebrovascular diseases (CeVD) in the cohort of Russian workers involved in recovery tasks after the Chernobyl accident. The studied cohort consists of 53,772 recovery operation workers (liquidators) who arrived in the zone of the Chernobyl accident within the first year after this accident (26 April 1986-26 April 1987). The mean external whole body dose in the cohort was 0.161 Gy, while individual doses varied from 0.0001 Gy to 1.42 Gy. During the follow-up period 1986-2012, a total of 23,264 cases of CeVD were diagnosed as a result of annual health examinations. A Poisson regression model was applied for estimation of radiation risks and for an assessment of other risk factors of CeVD. The following factors were considered as risk factors for CeVD: the dose, duration of the liquidators' work in the Chernobyl zone, and the concomitant diseases (hypertension, ischemic heart disease, atherosclerosis, and diabetes). The baseline incidence of CeVD is statistically significantly (p < 0.001) associated with all studied concomitant diseases. The incidence of CeVD has revealed a statistically significant dose response with the lack of a latent period and with the average ERR/Gy = 0.45, 95% CI: (0.28, 0.62), p < 0.001. Radiation risks of CeVD statistically significantly (p = 0.03) varied with the duration of liquidators' stay in the Chernobyl zone; for those who stayed in the Chernobyl zone less than 6 wk, ERR/Gy = 0.64, 95% CI = (0.38; 0.93), p < 0.001. Among studied concomitant diseases, diabetes mellitus statistically significantly (p = 0.002) increases the radiation risk of CeVD: for liquidators with diagnosed diabetes, ERR/Gy = 1.29.

  20. Mapping of caesium fallout from the Chernobyl accident in the Jotunheimen area

    Energy Technology Data Exchange (ETDEWEB)

    Baranwal, Vikas C.; Ofstad, Frode; Roenning, Jan S.; Watson, Robin J.

    2011-07-01

    As a consequence of the Chernobyl accident, several areas in Norway received radioactive fallout. One of these areas is the eastern part of Jotunheimen in central Norway. Immediately after the accident in 1986, the Geological Survey of Norway (NGU) performed airborne gamma-ray spectroscopy in central Norway. At that time, it was not possible to calculate reliable radionuclide concentrations, and the data were presented as total counts per second. Several man-made radionuclides were present in the initial fallout, but due to short half-lives, most of these have now disintegrated into stable isotopes. 137Cs, with a half-life of 11.000 days ({approx} 30 years) is still present in the environment in significant quantities, leading to high radioactivity levels in meat from reindeer and sheep. To obtain a detailed map of the caesium fallout concentration in Jotunheimen, an airborne gamma-ray spectrometry (AGRS) survey was carried out, focussing on reindeer grazing areas. This project was a cooperation between Reindeer Husbandry Administration, Norwegian Radiation Protection Authority and the Geological Survey of Norway. (auth)

  1. Transgenerational genomic instability in children of irradiated parents as a result of the Chernobyl Nuclear Accident

    Energy Technology Data Exchange (ETDEWEB)

    Aghajanyan, Anna, E-mail: ann-aghajanyan@yandex.ru [Cytogenetics Laboratory, FSI Russian Scientific Center of Roentgenology and Radiology, Profsoyuznaya 86, GSP-7, Moscow, 117997 (Russian Federation); Suskov, Igor [Laboratory of Ecological Genetics, N.I. Vavilov Institute of General Genetics Russian Academy of Sciences, Gybkin st. 3, Moscow 119991 (Russian Federation)

    2009-12-01

    The study of families irradiated as a result of the accident at the Chernobyl Nuclear Power Plant revealed significantly increased aberrant genomes frequencies (AGFs) not only in irradiated parents (n = 106, p < 0.01), but also in their children born after the accident (n = 159, p < 0.05). This is an indicative of the phenomenon of transgenerational genomic instability. To elucidate this phenomenon, experiments were undertaken to model genomic instability by using single and fractional in vitro {gamma}-irradiation ({sup 137}Cs) of peripheral blood samples from the children and their parents at doses of 0.1, 0.2 and 0.3 Gy. The spectrum and frequency of chromosome aberrations were studied in the 1st and 2nd cell generations. The average AGF was significantly increased at all doses (except 0.1 Gy) in children of irradiated parents, as compared to children born from non-irradiated parents. Amplification of cells with single-break chromosome aberrations in mitosis 2, as compared to mitosis 1, suggests the replication mechanism of realization of potential damage in DNA and the occurrence of genomic instability in succeeding cell generations.

  2. Database of meteorological and radiation measurements made in Belarus during the first three months following the Chernobyl accident.

    Science.gov (United States)

    Drozdovitch, Vladimir; Zhukova, Olga; Germenchuk, Maria; Khrutchinsky, Arkady; Kukhta, Tatiana; Luckyanov, Nickolas; Minenko, Victor; Podgaiskaya, Marina; Savkin, Mikhail; Vakulovsky, Sergey; Voillequé, Paul; Bouville, André

    2013-02-01

    Results of all available meteorological and radiation measurements that were performed in Belarus during the first three months after the Chernobyl accident were collected from various sources and incorporated into a single database. Meteorological information such as precipitation, wind speed and direction, and temperature in localities were obtained from meteorological station facilities. Radiation measurements include gamma-exposure rate in air, daily fallout, concentration of different radionuclides in soil, grass, cow's milk and water as well as total beta-activity in cow's milk. Considerable efforts were made to evaluate the reliability of the measurements that were collected. The electronic database can be searched according to type of measurement, date, and location. The main purpose of the database is to provide reliable data that can be used in the reconstruction of thyroid doses resulting from the Chernobyl accident.

  3. Chernobyl in the French mass media 14 years after the accident; Tchernobyl dans la presse francaise 14 ans apres

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2001-02-01

    The author presents how the mass media have dealt with the fourteenth anniversary of the Chernobyl accident. Nowadays Chernobyl epitomizes the hazards of nuclear energy. Public opinion has become extremely sensitive to topics concerning human health. This sensitivity is due to previous important affairs such as the scandal of the tainted blood, the mad cow disease or the syndrome of the Balkan war. Most media have broadened the debate to the sanitary impact of nuclear activities. The hyper-mediatization of the legal case of a man prosecuting the French state for no having taken adequate measures when the radioactive cloud spread over France, has given the feeling that French authorities have always wrongly minimized the consequences of the accident. (A.C.)

  4. Telomere length in Chernobyl accident recovery workers in the late period after the disaster.

    Science.gov (United States)

    Reste, Jelena; Zvigule, Gunda; Zvagule, Tija; Kurjane, Natalja; Eglite, Maija; Gabruseva, Natalija; Berzina, Dace; Plonis, Juris; Miklasevics, Edvins

    2014-11-01

    The outcome of the Chernobyl nuclear power plant (CNPP) accident was that a huge number of people were exposed to ionizing radiation. Previous studies of CNPP clean-up workers from Latvia revealed a high occurrence of age-associated degenerative diseases and cancer in young adults, as well as a high mortality as a result of cardiovascular disorders at age 45-54 years. DNA tandem repeats that cap chromosome ends, known as telomeres, are sensitive to oxidative damage and exposure to ionizing radiation. Telomeres are important in aging processes and carcinogenesis. The aim of this study was to investigate the long-term effect of protracted ionizing radiation exposure on telomere length in CNPP clean-up workers. Relative telomere length (RTL) was measured in peripheral blood leukocytes of 595 CNPP clean-up workers and 236 gender- and age-matched controls using real-time quantitative polymerase chain reaction (q-PCR). Close attention was paid to participation year and tasks performed during the worker's stay in Chernobyl, health status, and RTL differences between subgroups. Telomere shortening was not found in CNPP clean-up workers; on the contrary, their RTL was slightly greater than in controls (P = 0.001). Longer telomeres were found in people who worked during 1986, in those undertaking 'dirty' tasks (digging and deactivation), and in people with cancer. Shorter telomeres appeared frequently in those with cataract, osteoporosis, atherosclerosis, or coronary heart disease. We conclude that the longer telomeres revealed in people more heavily exposed to ionizing radiation probably indicate activation of telomerase as a chromosome healing mechanism following damage, and reflect defects in telomerase regulation that could potentiate carcinogenesis.

  5. RADIATION SITUATION STATUS OF THE TERRITORY OF OREL REGION, AFFECTED BY THE RADIOACTIVE CONTAMINATION DUE TO CHERNOBYL NPP ACCIDENT

    Directory of Open Access Journals (Sweden)

    G. L. Zakharchenko

    2009-01-01

    Full Text Available The article contains analysis of activities of Centers of State Sanitary and Epidemiological Inspection in Orel region during the first days after the Chernobyl NPP accident and consecutive years. The results of multi-year radiation and hygienic monitoring on the territory of Orel region are presented; efficiency of various measures of exposure dose reduction for the population of Orel region is analyzed.

  6. PECULIARITIES OF CURRENT DOSE ASSESSMENT FOR CHILDREN LIVING IN THE TERRITORIES RADIOACTIVELY CONTAMINATED DUE TO THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    A. V. Gromov

    2011-01-01

    Full Text Available The article outlines peculiarities of current dose assessment for the children living in the territories radioactively contaminated due to the Chernobyl accident. The results of annual exposure dose assessment for the children of various age groups and adult population of three subject territories of the Russian Federation referred to the zones of radioactive contamination are presented. A comparison of obtained estimations is done.

  7. The legacy of Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Bojcun, M.

    1991-04-20

    This article looks at daily life in the Northern Ukraine, where the fallout effects from the Chernobyl nuclear reactor accident were felt most keenly. High levels of radioactive iodine 131, strontium 90 and caesium 137 are still present five years on and the health of the population, including those evacuated from the exclusion zones, is at risk from leukaemia and thyroid problems, especially among children. Other worrying reports suggest the occurence of a new disease, ''Chernobyl AIDs'', in which sufferers' immune systems are depressed. Other major outstanding problems include the integrity of the concrete sarcophagus enclosing the damaged reactor, and the continued consumption of locally grown contaminated food due to government inadequacies in supplying ''clean'' equivalents. (UK).

  8. Radioecological and dosimetric consequences of the Chernobyl accident in France; Consequences radioecologiques et dosimetriques de l'accident de Tchernobyl en France

    Energy Technology Data Exchange (ETDEWEB)

    Renaud, Ph.; Beaugelin, K.; Maubert, H.; Ledenvic, Ph. [Inst. de Protection et de Surete Nucleaire, CEA Centre d' Etudes de Fontenay-aux-Roses, 92 (France)

    1997-11-01

    This study has as objective a survey of the radioecological and dosimetric consequences of the Chernobyl accident in France, as well as a prognosis for the years to come. It was requested by the Direction of Nuclear Installation Safety (DSIN) in relation to different organisms which effected measurements after this accident. It is based on the use of combined results of measurements and modelling by means of the code ASTRAL developed at IPSN. Various measurements obtained from five authorities and institutions, were made available, such as: activity of air and water, soil, processed food, agricultural and natural products. However, to achieve the survey still a modelling is needed. ASTRAL is a code for evaluating the ecological consequences of an accident. It allows establishing the correspondence between the soil Remnant Surface Activities (RSA, in Bq.m{sup -2}), the activity concentration of the agricultural production and the individual and collective doses resulting from external and internal exposures (due to inhalation and ingestion of contaminated nurture). The results of principal synthesis documents on the Chernobyl accident and its consequences were also used. The report is structured in nine sections, as follows: 1.Introduction; 2.Objective and methodology; 3.Characterization of radioactive depositions; 4;Remnant surface activities; 5.Contamination of agricultural products and foods; 6.Contamination of natural, semi-natural products and of drinking water; 7.Dosimetric evaluations; 8.Proposals for the environmental surveillance; 9.Conclusion. Finally, after ten years, one concludes that at presentthe dosimetric consequences of the Chernobyl accident in France were rather limited. For the period 1986-2046 the average individual effective dose estimated for the most struck zone is lower than 1500 {mu}Sv, which represents almost 1% of the average natural exposure for the same period. At present, the cesium 137 levels are at often inferior to those recorded

  9. Health consequences of Chernobyl. 25 years after the reactor catastrophy; Gesundheitliche Folgen von Tschernobyl. 25 Jahre nach der Reaktorkatastrophe

    Energy Technology Data Exchange (ETDEWEB)

    Pflugbeil, Sebastian; Schmitz-Feuerhake, Inge [Gesellschaft fuer Strahlenschutz e.V., Berlin (Germany); Paulitz, Henrik; Claussen, Angelika [Internationale Aerzte fuer die Verhuetung des Atomkrieges, Aerzte in sozialer Verantwortung e.V. (IPPNW), Berlin (Germany). Deutsche Sektion

    2011-04-15

    The report is an evaluation of studies indicating health effects as a consequence of the reactor catastrophe in Chernobyl. The most exposed population include the cleaning personnel (liquidators), the population evacuated from the 30 km zone, the populations in highly contaminated regions in Russia, Belarus and Ukraine, the European population in lass contaminated regions. The following issues are discussed: the liquidators, infant mortality, genetic and teratogenic damages, thyroid carcinoma and other thyroid diseases, carcinogenic diseases and leukemia, other diseases following the Chernobyl catastrophe.

  10. Advanced sodium fast reactor accident source terms :

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Dana Auburn; Clement, Bernard; Denning, Richard; Ohno, Shuji; Zeyen, Roland

    2010-09-01

    An expert opinion elicitation has been used to evaluate phenomena that could affect releases of radionuclides during accidents at sodium-cooled fast reactors. The intent was to identify research needed to develop a mechanistic model of radionuclide release for licensing and risk assessment purposes. Experts from the USA, France, the European Union, and Japan identified phenomena that could affect the release of radionuclides under hypothesized accident conditions. They qualitatively evaluated the importance of these phenomena and the need for additional experimental research. The experts identified seven phenomena that are of high importance and have a high need for additional experimental research: High temperature release of radionuclides from fuel during an energetic event Energetic interactions between molten reactor fuel and sodium coolant and associated transfer of radionuclides from the fuel to the coolant Entrainment of fuel and sodium bond material during the depressurization of a fuel rod with breached cladding Rates of radionuclide leaching from fuel by liquid sodium Surface enrichment of sodium pools by dissolved and suspended radionuclides Thermal decomposition of sodium iodide in the containment atmosphere Reactions of iodine species in the containment to form volatile organic iodides. Other issues of high importance were identified that might merit further research as development of the mechanistic model of radionuclide release progressed.

  11. Clastogenic factors in the plasma of Chernobyl accident recovery workers: Anticlastogenic effect of Ginkgo biloba extract

    Energy Technology Data Exchange (ETDEWEB)

    Emerit, I.; Levy, A.; Cernjavski, L. [Universite Paris (France)] [and others

    1995-11-01

    Clastogenic factors are found in the plasma of persons irradiated accidentally or therapeutically. They persisted in the plasma of A-bomb survivors over 30 years. Clastogenic factors were found in 33 or 47 Chernobyl accident recovery workers (often referred to as liquidators) in a previous study. In the present study, we show that there is a positive correlation between clastogenic activity and dose and that these biomarkers of oxidative stress can be influenced successfully by appropriate antioxidant treatment. With the authorization of the Armenian Ministry of Health, 30 workers were treated with antioxidants from Ginkgo biloba leaves. The extract EGb 761 containing flavonoids and terpenoids was given at a daily dose of 3 x 40 mg (Tanakan, IPSEN, France) during 2 months. The clastogenic activity of the plasma was reduced to control levels on the first day after the end of the treatment. A 1-year follow-up showed that the benefit of the treatment persisted for at least 7 months. One-third of the workers again had clastogenic factors after 1 year, demonstrating that the process which produced clastogenic factors continued. However, the observation that antioxidants do not have to be given continuously is encouraging for intervention trials on a large-scale basis. These appear justified, since clastogenic factors are thought to be risk factors for the development of late effects of irradiation. 43 refs., 6 tabs.

  12. Consequences of the Chernobyl accident for the natural and human environments

    Energy Technology Data Exchange (ETDEWEB)

    Dreicer, M. [Lawrence Livermore National Lab., CA (United States); Aarkog, A. [Risoe National Lab., Roskilde (Denmark); Alexakhin, R. [Russian Inst. of Agricultural Radiology and Agroecology (Russian Federation); Anspaugh, L. [Lawrence Livermore National Lab., CA (United States); Arkhipov, N.P. [Scientific and Technical Centre of the RIA `Pripyat` (Ukraine); Johansson, K.-J. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)

    1996-07-01

    In the ten years since the Chernobyl accident, an enormous amount of work has been done to assess the consequences to the natural and human environment. Although it is difficult to summarize such a large and varied field, some general conclusions can be drawn. This background paper includes the main findings concerning the direct impacts of radiation on the flora and fauna; the general advances of knowledge in the cycling of radionuclides in natural, seminatural and agricultural environments; some evaluation of countermeasures that were used; and a summary of the human radiation doses resulting from the environmental contamination. although open questions still remain, it can be concluded that: (1) at high radiation levels, the natural environment has shown short term impacts but any significant long term impacts remain to be seen; (2) effective countermeasures can be taken to reduce the transfer of contamination from the environment to humans but these are highly site specific and must be evaluated in terms of practicality as well as population does reduction; (3) the majority of the doses have already been received by the human population. If agricultural countermeasures are appropriately taken, the main source of future doses will be the gathering of food and recreational activities in natural and seminatural ecosystems.

  13. Further evidence for elevated human minisatellite mutation rate in Belarus eight years after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Dubrova, Yuri E.; Buard, Jerome; Jeffreys, Alec J. [Department of Genetics, University of Leicester, Adrian Building, University Road, Leicester (United Kingdom); Nesterov, Valeri N.; Krouchinsky, Nicolay G.; Ostapenko, Vladislav A. [Research Institute for Radiation Medicine, Mogilev (Belarus); Vergnaud, Gilles; Giraudeau, Fabienne [Laboratoire de Recherche en Genetique des Especes, Institut de Biologie, Nantes (France)

    1997-11-28

    Analysis of germline mutation rate at human minisatellites among children born in areas of the Mogilev district of Belarus heavily polluted after the Chernobyl accident has been extended, both by recruiting more families from the affected region and by using five additional minisatellite probes, including multi-locus probe 33.6 and four hypervariable single-locus probes. These additional data confirmed a twofold higher mutation rate in exposed families compared with non-irradiated families from the United Kingdom. An elevated rate was seen at all three independent sets of minisatellites (detected separately by multi-locus probes 33.15, 33.6 and six single-locus probes), indicating a generalised increase in minisatellite germline mutation rate in the Belarus families. Within the Belarus cohort, mutation rate was significantly greater in families with higher parental radiation dose estimated for chronic external and internal exposure to caesium-137, consistent with radiation induction of germline mutation. The spectra of mutation seen in the unexposed and exposed families were indistinguishable, suggesting that increased mutation observed over multiple loci arises indirectly by some mechanism that enhances spontaneous minisatellite mutation.

  14. Origin of a signal detected with the LSD detector after the accident at the chernobyl nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Agafonova, N. Yu., E-mail: natagafonova@gmail.com; Malgin, A. S., E-mail: malgin@lngs.infn.it [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation); Fulgione, W. [Istituto Nazionale di Fisica Nucleare, and Osservatorio Astrofisico di Torino, Istituto di Fisica dello Spazio Interplanetario (Italy)

    2013-08-15

    A rare signal was detected at 23:53 Moscow time on April 27, 1986 with the LSD low-background scintillation detector located under Mont Blanc at a distance of 1820 km from Chernobyl. To reveal the origin of this signal, we discuss the results obtained with other instruments operating within a similar program, as well as analyze the characteristics of the pulses of the signal and facts referring to the explosion of the Chernobyl reactor. A hypothesis based on detection with the LSD of gamma-quanta from {beta} decays of {sup 135}I nuclei ejected into atmosphere by the reactor explosion and carried in the underground detector camera with air of positive ventilation is considered. The explosion origin of the LSD signal indicates a new technogenic source of the background in the search for neutrino bursts from cores of collapsing stars.

  15. Origin of a signal detected with the LSD detector after the accident at the chernobyl nuclear power plant

    Science.gov (United States)

    Agafonova, N. Yu.; Malgin, A. S.; Fulgione, W.

    2013-08-01

    A rare signal was detected at 23:53 Moscow time on April 27, 1986 with the LSD low-background scintillation detector located under Mont Blanc at a distance of 1820 km from Chernobyl. To reveal the origin of this signal, we discuss the results obtained with other instruments operating within a similar program, as well as analyze the characteristics of the pulses of the signal and facts referring to the explosion of the Chernobyl reactor. A hypothesis based on detection with the LSD of gamma-quanta from β decays of 135I nuclei ejected into atmosphere by the reactor explosion and carried in the underground detector camera with air of positive ventilation is considered. The explosion origin of the LSD signal indicates a new technogenic source of the background in the search for neutrino bursts from cores of collapsing stars.

  16. Thyroid cancer in Ukraine after the Chernobyl accident (in the framework of the Ukraine–US Thyroid Project)

    Science.gov (United States)

    Tronko, Mykola; Mabuchi, Kiyohiko; Bogdanova, Tetiana; Hatch, Maureen; Likhtarev, Ilya; Bouville, Andre; Oliynik, Valeriy; McConnell, Robert; Shpak, Viktor; Zablotska, Lydia; Tereshchenko, Valeriy; Brenner, Alina; Zamotayeva, Galyna

    2014-01-01

    As a result of the accident at the Chernobyl Nuclear Power Plant, millions of residents of Belarus, Russia, and Ukraine were exposed to large doses of radioactive iodine isotopes, mainly I-131. The purpose of the Ukraine–American (UkrAm) and Belarus–American (BelAm) projects are to quantify the risks of thyroid cancer in the framework of a classical cohort study, comprising subjects who were aged under 18 years at the time of the accident, had direct measurements of thyroid I-131 radioactivity taken within two months after the accident, and were residents of three heavily contaminated northern regions of Ukraine (Zhitomir, Kiev, and Chernigov regions). Four two-year screening examination cycles were implemented from 1998 until 2007 to study the risks associated with thyroid cancer due to the iodine exposure caused during the Chernobyl accident. A standardised procedure of clinical examinations included: thyroid palpation, ultrasound examination, blood collection followed by a determination of thyroid hormone levels, urinary iodine content test, and fine-needle aspiration if required. Among the 110 cases of thyroid cancer diagnosed in UkrAm as the result of four screening examinations, 104 cases (94.5%) of papillary carcinomas, five cases (4.6%) of follicular carcinomas, and one case (0.9%) of medullary carcinoma were diagnosed. PMID:22394669

  17. Study of needles morphometric indexes in Scots pine trees in 25 years after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Makarenko, E.S. [Russian Institute of Agricultural Radiology and Agroecology, 249030, Obninsk, Russia, Kievskoe shosse 109 km (Russian Federation); Oudalova, A.A. [Russian Institute of Agricultural Radiology and Agroecology, 249030, Obninsk, Russia, Kievskoe shosse 109 km (Russian Federation); Obninsk Institute of Nuclear Power Engineering, National Research Nuclear University MEPhI, 249032, Obninsk, Russia, Studgorodok, 1 (Russian Federation)

    2014-07-01

    Long-term observations of coniferous tree populations within areas contaminated after radiation accidents provide unique information on biological consequences in plant populations from chronic radiation exposure. Many studies have been performed in a near zone of the Chernobyl NPP where in the primary period after the accident non-human biota was exposed to high doses, and dose rates essentially exceed natural radiation background up to now. Of special interest, however, are biological effects in plant and animal populations inhabiting territories with less pronounced exposure levels. Pine is especially important species for investigation in the field of environment radiation protection since it is included in the ICRP reference plants and animals list as one of the most radiosensitive plant species. The aim of this work was to estimate biological effects of chronic radiation impact for pine trees using needle indexes as test-functions. Study-sites are situated in the Bryansk Region of Russia contaminated after the Chernobyl accident. Scots pine populations under study have been growing in the radioactively contaminated areas over 20 years. In 2011 and 2013 samples of 2-years old needle were collected at 6 study-sites. {sup 137}Cs activities in soils at the time of sampling were from 1.57 to 96.9 kBq/kg. Estimated annual doses to pine tree crowns were calculated in a range of 7-130 mGy. Length and weight of the needles were measured, and necrosis rank was determined. Developmental disturbances were estimated via indexes of fluctuating asymmetry calculation for length (FA{sub L}) and weight (FA{sub W}) characteristics. Needle length of the Scots pine from study-sites ranged from 64.8 to 80.2 mm. Needle weight ranged from 18.2 to 30.5 mg, and was higher at radioactively contaminated sites in comparison to reference populations. Correlation of morphometric parameters and radiation impact was, however, statistically insignificant. Normal needle appeared with frequency

  18. Agricultural land management options after the Chernobyl and Fukushima accidents: The articulation of science, technology, and society.

    Science.gov (United States)

    Vandenhove, Hildegarde; Turcanu, Catrinel

    2016-10-01

    The options adopted for recovery of agricultural land after the Chernobyl and Fukushima accidents are compared by examining their technical and socio-economic aspects. The analysis highlights commonalities such as the implementation of tillage and other types of countermeasures and differences in approach, such as preferences for topsoil removal in Fukushima and the application of K fertilizers in Chernobyl. This analysis shows that the recovery approach needs to be context-specific to best suit the physical, social, and political environment. The complex nature of the decision problem calls for a formal process for engaging stakeholders and the development of adequate decision support tools. Integr Environ Assess Manag 2016;12:662-666. © 2016 SETAC.

  19. Effects of ionizing radiation on wildlife: what knowledge have we gained between the Chernobyl and Fukushima accidents?

    Science.gov (United States)

    Beresford, Nicholas A; Copplestone, David

    2011-07-01

    The recent events at the Fukushima Daiichi nuclear power plant in Japan have raised questions over the effects of radiation in the environment. This article considers what we have learned about the radiological consequences for the environment from the Chernobyl accident, Ukraine, in April 1986. The literature offers mixed opinions of the long-term impacts on wildlife close to the Chernobyl plant, with some articles reporting significant effects at very low dose rates (below natural background dose rate levels in, for example, the United Kingdom). The lack of agreement highlights the need for further research to establish whether current radiological protection criteria for wildlife are adequate (and to determine if there are any implications for human radiological protection).

  20. The Chernobyl and Fukushima Daiichi nuclear accidents and their tragic consequences

    CERN Document Server

    CERN. Geneva

    2016-01-01

    On April 26, 1986, the Unit 4 of the RBMK nuclear power plant of Chernobyl, in Ukraine, went out of control during a test at low-power, leading to an explosion and fire. The reactor building was totally demolished and very large amounts of radiation were released into the atmosphere for several hundred kilometres around the site including the nearby town of Pripyat. The explosion leaving tons of nuclear waste and spent fuel residues without any protection and control totally contaminating the entire area. Several hundred thousand people were affected by the radiation fall out. The radioactive cloud spread across Europe affecting most of the Northern, Central and Eastern European countries. Some areas of southern Switzerland, of northern Italy as well as western France were subject to radioactive contamination. The initiative of the G7 countries to launch and important programme for the closure of some Soviet built nuclear plants was accepted by several donor countries. A team of engineers was established wi...

  1. Investigations of radiocaesium in the natural terrestrial environment in Norway following the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Bretten, S. (Trondheim Univ. (Norway). Museum of Natural Sciences and Archaeology); Gaare, E.; Skogland, T. (Norwegian Inst. for Nature Research, Trondheim (Norway)); Steinnes, E. (Trondheim Univ. (Norway). Dept. of Chemistry)

    1992-03-01

    Radioactive fallout from the Chernobyl accident affected parts of central Norway to a considerable extent, in particular the {sup 134}Cs + {sup 137}Cs deposition had a significant impact on the natural environment. When this became apparent, a comprehensive radioecological research programme was initiated in order to study the behaviour of radiocaesium in boreal and alpine ecosystems, with emphasis on food-chains leading to exposure of species used for human consumption, i.e., reindeer and freshwater fish. In this paper results from the terrestrial part of this research programme during the period 1986-1990 are presented. The work was mainly confined to the mountain areas of Dovre and Rondane. Parallel studies were performed in eutrophic and strongly oligotrophic communities. The influence of local variations in topography and microclimate on the observed radiocaesium levels in topsoils, lichens and vascular plants was studied in detail. Currently a significant re-distribution of radiocaesium from the originally strongly exposed surfaces to those that were less exposed is observed. In the soil, radiocaesium is strongly retained in the litter and raw humus layers. Current levels in lichens are 1-2 orders of magnitude higher than in vascular plants. This strongly affects the seasonal variation of radiocaesium in reindeer, showing winter maxima of about 5 times higher than the August levels. The radiocaesium levels in reindeer showed a decline of approximately a factor of 3 during the period 1987-1990. Other animal species studied in the programme exhibited substantially lower radiocaesium levels than reindeer, but a considerable interspecies variation was observed. (author).

  2. Investigations of radiocaesium in the natural terrestrial environment in Norway following the Chernobyl accident.

    Science.gov (United States)

    Bretten, S; Gaare, E; Skogland, T; Steinnes, E

    1992-03-01

    Radioactive fallout from the Chernobyl accident affected parts of central Norway to a considerable extent, in particular the 134Cs+137Cs deposition had a significant impact on the natural environment. When this became apparent, a comprehensive radioecological research programme was initiated in order to study the behaviour of radiocaesium in boreal and alpine ecosystems, with emphasis on food-chains leading to exposure of species used for human consumption, i.e., reindeer and freshwater fish. In this paper results from the terrestrial part of this research programme during the period 1986-1990 are presented. The work was mainly confined to the mountain areas of Dovre and Rondane. Parallel studies were performed in eutrophic and strongly oligotrophic communities. The influence of local variations in topography and microclimate on the observed radiocaesium levels in topsoils, lichens and vascular plants was studied in detail. Currently a significant re-distribution of radiocaesium from the originally strongly exposed surfaces to those that were less exposed is observed. In the soil, radiocaesium is strongly retained in the litter and raw humus layers. Current levels in lichens are 1-2 orders of magnitude higher than in vascular plants. This strongly affects the seasonal variation of radiocaesium in reindeer, showing winter maxima of about 5 times higher than the August levels. The radiocaesium levels in reindeer showed a decline of approximately a factor of 3 during the period 1987-1990. Other animal species studied in the programme exhibited substantially lower radiocaesium levels than reindeer, but a considerable interspecies variation was observed.

  3. Ten years after the Chernobyl accident: reporting on nuclear and other hazards in six Swedish newspapers

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Aasa; Sjoeberg, L.; Waahlberg, A. af

    1997-07-01

    A European Commission sponsored study (RISKPERCOM) involving France, Norway, Spain, Sweden, and the UK, is concerned with surveying public perceptions of radiation related and other risks. This was partly done by distributing a questionnaire in each country at three different times in 1996: before, during and after the expected media attention given to the tenth anniversary of the Chernobyl accident. A selection of print media were analyzed, during a period of eight weeks - four weeks before the anniversary, and four weeks after - making it possible to contrast any changes between the three waves of the questionnaire with the results of the media study. The present report aims at providing a picture of the Swedish media coverage of different kinds of risks during the period referred to above. The purpose of the analysis is thus primarily of a descriptive nature; explanatory factors are only considered in an ad hoc manner while discussing the results and their possible implications. Naturally, the findings arising from this study cannot alone serve as a basis for making statements about the effects of risk related content on the Swedish newspaper readers. The risk stories included in the analysis were those dealing with one or more of the twenty different hazard items referred to in several of the questions in the RISKPERCOM questionnaire. Radiation and nuclear power energy were not the only issues of concern. The selection covered a wide range of other hazards as well, in order to provide for a wide risk panorama, thus making it possible to compare specific risk qualities etc., as these were presented in the media 70 refs, 40 refs

  4. Investigations on Health Conditions of Chernobyl Nuclear Power Plant Accident Recovery Workers from Latvia in Late Period after Disaster

    Directory of Open Access Journals (Sweden)

    Reste Jeļena

    2016-10-01

    Full Text Available The paper summarises the main findings on Chernobyl Nuclear Power Plant (CNPP accident recovery workers from Latvia and their health disturbances, which have been studied by the authors during the last two decades. Approximately 6000 persons from Latvia participated in CNPP clean-up works in 1986–1991. During their work period in Chernobyl they were exposed to external as well as to internal irradiation, but since their return to Latvia they were living in a relatively uncontaminated area. Regular careful medical examinations and clinical studies of CNPP clean-up workers have been conducted during the 25 years after disaster, gathering knowledge on radiation late effects. The aim of the present review is to summarise the most important information about Latvian CNPP clean-up worker health revealed by thorough follow-up and research conducted in the period of 25 years after the accident. This paper reviews data of the Latvian State Register of Persons Exposed to Radiation due to CNPP Accident and gives insight in main health effects found by the researchers from the Centre of Occupational and Radiological Medicine (Pauls Stradiņš Clinical University Hospital and Rīga Stradiņš University in a number of epidemiological, clinical, biochemical, immunological, and physiological studies. Latvian research data on health condition of CNPP clean-up workers in the late period after disaster indicate that ionising radiation might cause premature ageing and severe polymorbidity in humans.

  5. Infrared investigation of hard human teeth tissues exposed to various doses of ionizing radiation from the 1986 Chernobyl accident

    OpenAIRE

    Darchuk, L. A.; Zaverbna, L. V.; Bebeshko, V. G.; Worobiec, A.; Stefaniak, E. A.; Van Grieken, R.

    2008-01-01

    Infrared spectroscopy (IR) was applied to study changes in solid teeth tissues of persons exposed to low (0.12–0.20 Gy) and high (0.5–1.7 Gy) doses of ionizing radiation during their work in the Chernobyl zone after the accident. Changes in the inorganic and organic matrix of teeth were noted for both high and low radiation doses. The obtained results demonstrated that high doses of radiation lead to imbalance between phosphate–carbonate phases level (because of increasing of CO32− content) a...

  6. Dose rate mapping and quantitative analysis of radioactive deposition with simple monitoring instruments in Finland after the Chernobyl accident.

    Energy Technology Data Exchange (ETDEWEB)

    Koivukoski, J. [Ministry of the Interior, Rescue Dept., Helsinki (Finland); Paatero, J. [Finnish Meteorological Inst., Helsinki (Finland)], E-mail: janne.koivukoski@intermin.fi

    2013-03-01

    This article reviews the Finnish dose-rate mapping equipment and the system to process the obtained results, which were used immediately after the 1986 Chernobyl accident. We present the results of the external gamma-radiation monitoring carried out with simple civil-defence gamma monitoring instruments and compare them with the subsequent deposition mapping performed with research-grade instruments. The analysis shows that the quality of radiation mapping is good enough for decision makers to direct protective measures to the right areas. This review also demonstrates that a simple stationary external gamma radiation monitoring network can be effectively used for early warning in radiation emergency situations. (orig.)

  7. PRYMA-TO: A model of radionuclide transfer from air into food stuff. Test with data from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Olivares, A.; Carrasco, E.; Suanez, A.; Josep, L.

    1994-07-01

    This report describes a dynamical model developed in the Environmental Institute of the CIEMAT. Its aims are the calculation of the integrated as well as time-dependent concentrations of ''131l and ''137Cs over time in soils, in forage pasture (or other vegetation species), and in milk and meat. The source contamination is assumed to come from a radioactive cloud confined in the atmospheric mixing layer. Data monitored in different locations the days following the Chernobyl accident have been used. The model was tested against post-Chernobyl data from 13 locations around the world, in the framework of the A4 exercise from the BIOMOVS program (Biospheric Models Validation Studies). The performance of the model is illustrated in 9 scenarios which have been chosen of these 13 because they have more information or they are better described. Default Probability Density Functions for the main parameters used by the model have been obtained by statistical processing of some post-Chernobyl evidence. (Author) 30 refs.

  8. About Chernobyl - Twenty Years Later; Propos sur Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M

    2006-07-01

    The author discusses the reactor accident of Chernobyl, the information on its consequences so contradictory in the former USSR countries, the status of the effects observed, the forecasting concerning the onset of cancers in the coming years among the populations that were exposed to radiations, the public opinion facing the pessimists. He concludes on the lessons which can be drawn from Chernobyl. (A.L.B.)

  9. Rehabilitation of living conditions in territories contaminated by the Chernobyl accident: the ETHOS project.

    Science.gov (United States)

    Lochard, Jacques

    2007-11-01

    The ETHOS Project, supported by the radiation protection research program of the European Commission (EC), was implemented in the mid-1990's with the support of the Belarus authorities as a pilot project to initiate a new approach for the rehabilitation of living conditions in the contaminated territories of the Republic. This initiative followed a series of studies performed in the context of the EC Community of Independent States cooperation program to evaluate the consequences of the Chernobyl accident (1991-1995), which clearly brought to the fore that a salient characteristic of the situation in these territories was the progressive and general loss of control of the population on its daily life. Furthermore, due to the economic difficulties during the years following the breakdown of the USSR, the population was developing private production and, in the absence of know-how and adequate means to control the radiological quality of foodstuffs, the level of internal exposure was rising significantly. The aim of the project was primarily to involve directly the population wishing to stay in the territories in the day-to-day management of the radiological situation with the goal of improving their protection and their living conditions. It was based on clear ethical principles and implemented by an interdisciplinary team of European experts with specific skills in radiation protection, agronomy, social risk management, communication, and cooperation in complex situations, with the support of local authorities and professionals. In a first phase (1996-1999), the ETHOS Project was implemented in a village located in the Stolyn District in the southern part of Belarus. During this phase, a few tens of villagers were involved in a step-by-step evaluation of the local radiological situation to progressively regain control of their daily life. In a second phase (1999-2001), the ETHOS Project was extended to four other localities of the District with the objective to

  10. Chernobyl operators: criminals or victims?

    Science.gov (United States)

    Munipov, V M

    1992-10-01

    The blame for the 1986 Chernobyl disaster has been variously attributed to the operating personnel, the plant management, the design of the reactor, and the lack of adequate safety information in the Soviet nuclear industry. This paper considers a number of design faults, operational shortcomings and human errors that combined in the accident. It examines the sequence of events leading up to the accident, design problems in the reactor and cooling rods, and the course of the accident itself. It considers the ergonomics aspects, and expresses the view that the main cause of the accident was inadequate human-machine interaction. Finally, it stresses the continuing inadequacies of the Soviet nuclear system, and emphasizes that unless the ergonomics lessons are fully learned, a similar disaster could still occur.

  11. THE DYNAMICS OF FOOD RATIONS OF BRYANSK REGION POPULATION LIVING IN THE TERRITORIESCONTAMINATED AFTER THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. G. Travnikova

    2014-01-01

    Full Text Available During the years passed after the Chernobyl accident we are carrying out monitoring of the radiation situation in the Sough-Western territories of the Bryansk region, contaminated with the long-living radionuclides which includes 137Сs concentration measurements in agricultural and natural foodstuffs, surveys of local populations on the structure and composition of the diet accompanied with 137Сs content measurements in the human body. In the article the obtained data is systematized on the food rations of the adult population of theBryansk region, on food rations dynamics in the first and following years after the accident, which is necessary for the correct estimation of internal exposure doses of the population living on the contaminated territories.

  12. Outcome of pregnancy in one Norwegian county 3 years prior to and 3 years subsequent to the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Ulstein, M.; Skeie Jensen, T.; Irgens, L.M.; Lie, R.T.; Sivertsen, E. (Univ. of Bergen (Norway). Dept. of Obstetrics and Gynecology, and Medical Birth Registry)

    1990-01-01

    Pregnancy outcome was studied in a county in Norway 3 years prior to and 3 years subsequent to the Chernobyl nuclear plant accident on 26th April 1986. More detailed analyses have been performed for the 12 months prior to and subsequent to the accident. A significant increase in the spontaneous abortion rate the first year after the accident was followed by a slight decrease during the second and third years, but figures were still higher than the period prior to the accident. The rate of legal abortions was unchanged. During the entire observation period the number of births increased continuously, with the exception of a decrease in the last 2 months of 1986 and the first month of 1987. A higher incidence of spontaneous abortions was found for pregnancies conceived during the first 3 months after the accident. This increase in the spontaneous abortion rate is noteworthy, and more especially its long-term persistence, which cannot be the results of external radiation. The internal radiation from food polluted by radioactive fallout is a possible explanation. Changes in nutrition in order to avoid polluted food may also be of importance. (authors).

  13. Thyroid ultrasound findings 7 years after the Chernobyl accident. A comparative epidemiological study in the Bryansk region of Russia

    Energy Technology Data Exchange (ETDEWEB)

    Kumpusalo, L. [Univ. of Kuopio (Finland). Dept. of Clinical Radiology; Kumpusalo, E. [Univ. of Kuopio (Finland). Community Health and General Practice; Soimakallio, S. [Univ. of Kuopio (Finland). Dept. of Clinical Radiology; Salomaa, S. [Finnish Center for Radiation and Nuclear Safety, Helsinki (Finland); Paile, W. [Finnish Center for Radiation and Nuclear Safety, Helsinki (Finland); Kolmakow, S. [Univ. of Kuopio (Finland). Oral Pathology, Roentgenology and Forensic Odontology; Zhukowsky, G. [National Research Center for Preventive Medicine, Ministry of Health, Moscow (Russian Federation); Ilchenko, I. [National Research Center for Preventive Medicine, Ministry of Health, Moscow (Russian Federation); Nissinen, A. [Univ. of Kuopio (Finland). Community Health and General Practice

    1996-11-01

    Aims: The accident at the Chernobyl nuclear power station occurred in April 1986. We report on a comparative epidemiological study on thyroid abnormalities in the contaminated and uncontaminated populations of the Bryansk region, South-West Russia, in 1993, 7 years after the accident. Material and Methods: The study material consisted of all inhabitants aged 3-34 years in the contaminated village of Mirnyi and in the uncontaminated village of Krasnyi Rog, excluding those who had moved to be villages after the accident. The total material comprised 302 inhabitants in Mirnyi and 200 in Krasnyi Rog. Results: No pathological US findings in either village were found in children born after the accident. In the age group 0-9 years old at the time of the accident, the prevalence of thyroid abnormalities was 8.1% in the contaminated village compared to 1.6% in the uncontaminated village. In the age group 10-27 years the corresponding figures were 18.8% and 17.7%. Only 55% of the pathological US findings were detected by physical palpation. Conclusion: The total prevalence of thyroid abnormalities was higher among children in the contaminated village. We recommend an active screening of young contaminated subjects with US, supplemented with fine needle biopsy. (orig.).

  14. Have the consequences of reactor accidents for the population been well assessed? Six questions to the experts in the field

    Energy Technology Data Exchange (ETDEWEB)

    Pohl, Peter

    2016-07-15

    Six questions to the experts in the field are posed: (1) Why is the assessment of accident consequences not separated in long-term and peak exposure? (2) Why is the exposure due to I-131 seen critical mainly in regard to the thyroid? (3) Do you have any reliable relations of health risk versus peak exposure? (4) Why do you not abolish the LNT assumption and replace it with a threshold model? (5) Why do you include indirect, psycho-somatic effects in assessing the consequences of reactor accidents when this is not customary with accidents with often more casualties? (6) How can the number of Chernobyl-assigned thyroid cancers have risen from some 600 about to some 4,000 today, when the latency period is in the range of 4 to 5 years?.

  15. Modeling the early-phase redistribution of radiocesium fallouts in an evergreen coniferous forest after Chernobyl and Fukushima accidents

    Energy Technology Data Exchange (ETDEWEB)

    Calmon, P.; Gonze, M.-A.; Mourlon, Ch.

    2015-10-01

    Following the Chernobyl accident, the scientific community gained numerous data on the transfer of radiocesium in European forest ecosystems, including information regarding the short-term redistribution of atmospheric fallout onto forest canopies. In the course of international programs, the French Institute for Radiological Protection and Nuclear Safety (IRSN) developed a forest model, named TREE4 (Transfer of Radionuclides and External Exposure in FORest systems), 15 years ago. Recently published papers on a Japanese evergreen coniferous forest contaminated by Fukushima radiocesium fallout provide interesting and quantitative data on radioactive mass fluxes measured within the forest in the months following the accident. The present study determined whether the approach adopted in the TREE4 model provides satisfactory results for Japanese forests or whether it requires adjustments. This study focused on the interception of airborne radiocesium by forest canopy, and the subsequent transfer to the forest floor through processes such as litterfall, throughfall, and stemflow, in the months following the accident. We demonstrated that TREE4 quite satisfactorily predicted the interception fraction (20%) and the canopy-to-soil transfer (70% of the total deposit in 5 months) in the Tochigi forest. This dynamics was similar to that observed in the Höglwald spruce forest. However, the unexpectedly high contribution of litterfall (31% in 5 months) in the Tochigi forest could not be reproduced in our simulations (2.5%). Possible reasons for this discrepancy are discussed; and sensitivity of the results to uncertainty in deposition conditions was analyzed. - Highlights: • Transfer of radiocesium atmospheric fallout in evergreen forests was modeled. • The model was tested using observations from Chernobyl and Fukushima accidents. • Model predictions of canopy interception and depuration agree with measurements. • Unexpectedly high contribution of litterfall for the

  16. INFLUENCE OF ANTIHYPERTENSIVE THERAPY ON PSYCHOLOGICAL STATUS OF CHERNOBYL NUCLEAR POWER PLANT ACCIDENT CONSEQUENCES LIQUIDATORS

    Directory of Open Access Journals (Sweden)

    E. M. Manoshkina

    2006-01-01

    Full Text Available Aim. To study psychological status and influence of antihypertensive therapy (AHT on it in Chernobyl nuclear power plant (NPP accident consequences liquidators, who suffer arterial hyper-tension (AH, with controlled treatment compared to the standard treatment in out-patient clinic. Material and methods. 81 liquidators with AH (all men were included into open compara-tive randomized study. Study duration was 12 months. Patients were randomized into main group (MG and control group (CG. Patients of MG received strictly regulated stepped AHT based on ACE inhibitor spirapril 6 mg daily (Quadropril®, Pliva-AVD, hypothiazide was added if necessary (12.5-25 mg daily and afterwards – atenolol (12.5-100 mg daily. In CG AHT and its correction was set by physician in polyclinic. Brief multifactor questionnaire for personality analysis was used to study psychological status. Results. 57 patients completed the study, 28 in MG and 29 in CG. In MG target blood pres-sure (BP levels were reached in 22 (78.6% patients, in CG – in 11 (38% patients (p<0.01. The main feature of psychological status of liquidators with AH was hypochondriac, depressive and anxious disorders. Controlled AHT made it possible to reach improvement in psychological status, i.e. growth of optimism and activity of patients, more often, than standard treatment in out-patient clinics. Increase in number of patients with pronounced anxious changes was observed in CG. Effi-ciency of AHT in liquidators with AH is connected with severity of depressive disturbances: in subgroups with inefficient treatment patients had the highest level of depression. In liquidators with AH, possessing neurotic disturbances, spirapril was efficient both as monotherapy, and in combina-tion with diuretic hydrochlorothiazide and beta-blocker atenolol. Conclusion. Controlled AHT in liquidators with AH has advantages over standard treatment in out-patient clinic and results in more frequent target BP level

  17. The Chernobyl accident: Can lichens be used to characterize a radiocesium contaminated range?

    Directory of Open Access Journals (Sweden)

    Eldar Gaare

    1987-06-01

    Full Text Available Many of the lichen species that are important in the lichen dominated plant communities in the Norwegian mountains are important reindeer winter forage. They are also organisms that collect fall-out from the atmosphere. The Chernobyl accident brought, among other, radioactive Cesium, and from lichens this follow the food chain to reindeer and finally man. From region to region this fall-out was unevenly distributed and methods are needed to compare winter ranges and to monitor the developement of radioactive levels in the lichen carpet. Cornicularia divergens, Alectoria ochroleuca, Cetraria nivalis, Cladina mitis, C. stellaris and Stereocaulon pa¬schale was collected in the Dovre mountains to compare species levels and to study collection methods. We found that from spot to spot there is a very large variation between samples, even within the same species. Because of this we are not able to show significant species differences. We found, however, that species from more or less snow free ridgetops, Cornicularia divergens, Alectoria ochroleuca, Cetraria nivalis and Cladina mitis showed less variation and thus must be recommended as the best species for monitoring and comparison of ranges.Tsjernobyl-ulykken: Kan lav nyttes til karakterisering av et radioaktivt forurenset reinbeite?Abstract in Norwegian / Sammendrag: Mange av de lavarter som er viktige i lavdominerte plantesamfunn i de norske fjell er viktige som vinterfor for rein. Disse organismer samler også nedfall fra atmosfæren. Ulykken i Tsjernobyl brakte, blant annet, radioaktivt cesium, og fra lav følger dette næringskjeden til rein og endelig mennesket. Fra område til område var dette nedfallet ujevnt fordelt, og det kreves metoder for å sammenligne vinterområder og for å overvåke utviklingen av det radioaktive nivå i lavmattene. Cornicularia divergens, Alectoria ochroleuca, Cetraria nivalis, Cladina mitis, C. stellaris og Stereocaulon paschale ble samlet på Dovrefjell for

  18. Reactor Safety Gap Evaluation of Accident Tolerant Components and Severe Accident Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, Mitchell T. [Argonne National Lab. (ANL), Argonne, IL (United States); Bunt, R. [Southern Nuclear, Atlanta, GA (United States); Corradini, M. [Univ. of Wisconsin, Madison, WI (United States); Ellison, Paul B. [GE Power and Water, Duluth, GA (United States); Francis, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Gabor, John D. [Erin Engineering, Walnut Creek, CA (United States); Gauntt, R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Henry, C. [Fauske and Associates, Burr Ridge, IL (United States); Linthicum, R. [Exelon Corp., Chicago, IL (United States); Luangdilok, W. [Fauske and Associates, Burr Ridge, IL (United States); Lutz, R. [PWR Owners Group (PWROG); Paik, C. [Fauske and Associates, Burr Ridge, IL (United States); Plys, M. [Fauske and Associates, Burr Ridge, IL (United States); Rabiti, Cristian [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rempe, J. [Rempe and Associates LLC, Idaho Falls, ID (United States); Robb, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Wachowiak, R. [Electric Power Research Inst. (EPRI), Knovville, TN (United States)

    2015-01-31

    The overall objective of this study was to conduct a technology gap evaluation on accident tolerant components and severe accident analysis methodologies with the goal of identifying any data and/or knowledge gaps that may exist, given the current state of light water reactor (LWR) severe accident research, and additionally augmented by insights obtained from the Fukushima accident. The ultimate benefit of this activity is that the results can be used to refine the Department of Energy’s (DOE) Reactor Safety Technology (RST) research and development (R&D) program plan to address key knowledge gaps in severe accident phenomena and analyses that affect reactor safety and that are not currently being addressed by the industry or the Nuclear Regulatory Commission (NRC).

  19. Using a bank of predatory fish samples for bioindication of radioactive contamination of aquatic food chains in the area affected by the Chernobyl accident.

    Science.gov (United States)

    Kryshev, I I; Ryabov, I N; Sazykina, T G

    1993-11-01

    From the analysis of experimental data on radioactive contamination of various fish, it is suggested that predatory fish specimens can be used as bioindicators of radionuclide accumulation in reservoir food chains of the Chernobyl emergency area. The increased content of cesium radionuclides were detected in the muscle tissue of predatory fish collected in various regions of the Chernobyl emergency area. In most of the water bodies studied, maximum contamination levels of predatory fish by radionuclides of cesium occurred in 1987-1988, whereas in 'nonpredatory' fish the concentration of cesium was maximum, as a rule, in the first year following the accident. The exposure doses of fish of various ecological groups and ages are estimated. The exposure doses of various population groups, using fish from contaminated water bodies, are also estimated. When forming the environmental data bank for the Chernobyl accident zone it is suggested that perch, pike-perch and pike be used as bioindicators of radioactive contamination of food chains.

  20. Thyroid cancer among Ukrainians and Belarusians who were children or adolescents at the time of the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P [GSF-Institute of Radiation Protection, Neuherberg (Germany); Bogdanova, T I [Institute of Endocrinology and Metabolism of the Academy of Medical Sciences of Ukraine, Kyiv, Ukraine (Ukraine); Buglova, E [Research Institute of Radiation Medicine and Endocrinology, Minsk (Belarus); Chepurniy, M [Ukrainian Radiation Protection Institute, Kyiv (Ukraine); Demidchik, Y [Belarus State Medical University, Minsk, Belarus (Belarus); Gavrilin, Y [State Research Center-Institute of Biophysics, Moscow (Russian Federation); Kenigsberg, J [Research Institute of Radiation Medicine and Endocrinology, Minsk (Belarus); Kruk, J [Research Institute of Radiation Medicine and Endocrinology, Minsk (Belarus); Schotola, C [GSF-Institute of Radiation Protection, Neuherberg (Germany); Shinkarev, S [State Research Center-Institute of Biophysics, Moscow (Russian Federation); Tronko, M D [Institute of Endocrinology and Metabolism of the Academy of Medical Sciences of Ukraine, Kyiv, Ukraine (Ukraine); Vavilov, S [Ukrainian Radiation Protection Institute, Kyiv (Ukraine)

    2006-03-15

    Our objective is to assess the regional and temporal dependences of the baseline cases contributing to thyroid cancer incidence among those exposed in childhood or during adolescence in Belarus and Ukraine after the Chernobyl accident. Data are analysed for Kyiv and Sevastopol City and the 25 oblasts (regions) in Ukraine, and for Minsk and Gomel City and the 6 oblasts in Belarus. Average thyroid doses due to the Chernobyl accident were assessed for every birth year in the period from 1968 to 1985. Case data pertain to people who underwent surgical removal of thyroid cancers during the period 1986 to 2001 and who were allocated to their place of residence at the time of the accident. The 35 oblasts/cities were subdivided into an upper, middle and lower group of baseline thyroid cancer incidence. Poisson regressions were performed to estimate age, time and gender dependences of the baseline incidence rates in the three groups. The majority of oblasts/cities with high average doses and the majority of Belarusian oblasts/cities belong to the upper group of baseline thyroid cancer incidence. The baseline in the upper group is estimated to be larger than in the middle group by a factor of 2.3, and by a factor of 4.0 when compared to the lower group. The baseline incidence increases with age and with time since exposure. Estimated baseline incidence rates were found to increase from 1988 to 1999 by factors of three and two for the upper and the two lower groups respectively. The estimated thyroid cancer incidence rates in Belarus and Ukraine, and their dependences on gender and age, are consistent with observed rates found in the larger cancer registries of other countries. In conclusion, the baseline cases are found to contribute about 70% to the thyroid cancer incidence in Ukraine, and about 40% to the incidence in Belarus.

  1. Nuclear safety in light water reactors severe accident phenomenology

    CERN Document Server

    Sehgal, Bal Raj

    2011-01-01

    This vital reference is the only one-stop resource on how to assess, prevent, and manage severe nuclear accidents in the light water reactors (LWRs) that pose the most risk to the public. LWRs are the predominant nuclear reactor in use around the world today, and they will continue to be the most frequently utilized in the near future. Therefore, accurate determination of the safety issues associated with such reactors is central to a consideration of the risks and benefits of nuclear power. This book emphasizes the prevention and management of severe accidents to teach nuclear professionals

  2. Surface activity distribution measurements and establishment of a dose rate map inside the destroyed Chernobyl reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chesnokov, A.V.; Fedin, V.I.; Gulyaev, A.A. [RECOM Ltd., Moscow (Russian Federation)] [and others

    1999-02-01

    A Gamma Locator designed for contamination survey inside the reactor hall of the 4th unit of Chernobyl NNP has been developed. The device consists of a detector head and a remote control computer connected by a 150 m long cable. The detector head (dimensions: 500 mm by 500 mm by 400 mm; weight: about 40 kg) is a collimated scintillation gamma detector (the collimation angle is 10 deg.). It is installed on a scanning unit and was placed inside the reactor hall. The Gamma Locator scans all surfaces of the reactor hall with angular steps ({<=} 1 deg. vertically as well as horizontally) and the particle fluence from the corresponding direction is recorded. The distance between the device head and the measured surface is instantaneously registered by a laser distance gauge. Inside the collimator there is a small CCD camera which makes it possible to obtain a visible image of the measured surface. The effective surface activity levels are presented in colour on the screen of the control computer. The gamma detector essentially consists of a CsI(TI) scintillator crystal ({phi} 8 mm in diameter, 2.5 mm in thickness) and a Si photodiode. The detector energy resolution is about 8% for radiation from {sup 137}Cs. The exposure dose rate distribution in the reactor hall is estimated from the measured effective surface activities ({sup 137}Cs is the main gamma emitting isotope inside the reactor hall). The results of dose rate calculations are presented in colour superposed on a drawing of the reactor hall. (au) 1 tab., 28 ills., 16 refs.

  3. Has fallout from the Chernobyl accident caused childhood leukaemia in Europe? An update on epidemiologic evidence

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, W. [Bremen Inst. for Prevention Research and Social Medicine (BIPS), Bremen (Germany)

    2001-07-01

    Background: According to radiation risk estimates uniformly adopted by various official organizations, exposure to Chernobyl fallout is unlikely to have caused any measurable health risk in central Europe. Methods and Results: A reevaluation of ECLIS (European Childhood Leukaemia and Lymphoma Incidence Study), a large IARC-coordinated project revealed a slightly higher leukaemia incidence in the most contaminated European regions, and an increasing trend with estimated cumulative excess radiation dose. The excess corresponds to 20 cases of childhood leukaemia in the study area until 1991. Recent evidence from Greece and Germany indicate significantly higher risks in the cohort of children in utero at the time of the initial fallout. In Greece, a positive trend was observed over three regions of increasing average fallout contamination (p=0.005). Conclusion: Chernobyl fallout could well have caused a small, but significant excess of childhood leukaemia cases in Europe. The etiologic mechanism might include an induction of chromosome aberrations in early pregnancy. Increased risks in the birth cohort exposed in utero correspond to 11 excess cases in Greece and another 11.4 excess cases in Germany alone. Exposure misclassification and underascertainment of incident cases render post-Chernobyl risk estimates probably too low. If indeed Chernobyl fallout has caused childhood leukaemia cases in Europe, we would also expect an increased incidence for other childhood cancers and excess malignancies in adults as well as non-malignant diseases of all ages. Neither of these endpoints have as yet been systematically studied. (orig.)

  4. Review of accident analyses of RB experimental reactor

    Directory of Open Access Journals (Sweden)

    Pešić Milan P.

    2003-01-01

    Full Text Available The RB reactor is a uranium fuel heavy water moderated critical assembly that has been put and kept in operation by the VTNCA Institute of Nuclear Sciences, Belgrade, Serbia and Montenegro, since April 1958. The first complete Safety Analysis Report of the RB reactor was prepared in 1961/62 yet, the first accident analysis had been made in late 1958 with the aim to examine a power transition and the total equivalent doses received by the staff during the reactivity accident that occurred on October 15, 1958. Since 1960, the RB reactor has been modified a few times. Beside the initial natural uranium metal fuel rods, new types of fuel (TVR-S types of Russian origin consisting of 2% enriched uranium metal and 80% enriched UO2 dispersed in aluminum matrix, have been available since 1962 and 1976 respectively. Modifications of the control and safety systems of the reactor were made occasionally. Special reactor cores were designed and constructed using all three types of fuel elements as well as the coupled fast-thermal ones. The Nuclear Safety Committee of the VINĆA Institute, an independent regulatory body, approved for usage all these modifications of the RB reactor on the basis of the Preliminary Safety Analysis Reports, which, beside proposed technical modifications and new regulation rules, included safety analyses of various possible accidents. A special attention was given (and a new safety methodology was proposed to thorough analyses of the design-based accidents related to the coupled fast-thermal cores that included central zones of the reactor filled by the fuel elements without any moderator. In this paper, an overview of some accidents, methodologies and computation tools used for the accident analyses of the RB reactor is given.

  5. Chernobyl, 14 years later; Tchernobyl, 14 ans apres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This report draws an account of the consequences of Chernobyl accident 14 years after the disaster. It is made up of 8 chapters whose titles are: (1) Some figures about Chernobyl accident, (2) Chernobyl nuclear power plant, (3)Sanitary consequences of Chernobyl accident, (4) The management of contaminated lands, (5) The impact in France of Chernobyl fallout, (6) International cooperation, (7) More information about Chernobyl and (8) Glossary.

  6. Comparative radiation impact on biota and man in the area affected by the accident at the Chernobyl nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Fesenko, S.V. [Russian Institute of Agricultural Radiology and Agroecology, Kievskoe shosse, Kaluga region, Obninsk 249020 (Russian Federation) and International Atomic Energy Agency, Agency' s Laboratories, Seibersdorf A-2444 (Austria)]. E-mail: s.fesenko@iaea.org; Alexakhin, R.M. [Russian Institute of Agricultural Radiology and Agroecology, Kievskoe shosse, Kaluga region, Obninsk 249020 (Russian Federation); Geras' kin, S.A. [Russian Institute of Agricultural Radiology and Agroecology, Kievskoe shosse, Kaluga region, Obninsk 249020 (Russian Federation); Sanzharova, N.I. [Russian Institute of Agricultural Radiology and Agroecology, Kievskoe shosse, Kaluga region, Obninsk 249020 (Russian Federation); Spirin, Ye.V. [Russian Institute of Agricultural Radiology and Agroecology, Kievskoe shosse, Kaluga region, Obninsk 249020 (Russian Federation); Spiridonov, S.I. [Russian Institute of Agricultural Radiology and Agroecology, Kievskoe shosse, Kaluga region, Obninsk 249020 (Russian Federation); Gontarenko, I.A. [Russian Institute of Agricultural Radiology and Agroecology, Kievskoe shosse, Kaluga region, Obninsk 249020 (Russian Federation); Strand, P. [Norwegian Radiation Protection Authority, Oesteras (Norway)

    2005-07-01

    A methodological approach for a comparative assessment of ionising radiation effects on man and non-human species, based on the use of Radiation Impact Factor (RIF) - ratios of actual exposure doses to biota species and man to critical dose is described. As such doses, radiation safety standards limiting radiation exposure of man and doses at which radiobiological effects in non-human species were not observed after the Chernobyl accident, were employed. For the study area within the 30 km ChNPP zone dose burdens to 10 reference biota groups and the population (with and without evacuation) and the corresponding RIFs were calculated. It has been found that in 1986 (early period after the accident) the emergency radiation standards for man do not guarantee adequate protection of the environment, some species of which could be affected more than man. In 1991 RIFs for man were considerably (by factor of 20.0-1.1 x 10{sup 5}) higher compared with those for selected non-human species. Thus, for the long term after the accident radiation safety standards for man are shown to ensure radiation safety for biota as well.

  7. Modeling the early-phase redistribution of radiocesium fallouts in an evergreen coniferous forest after Chernobyl and Fukushima accidents.

    Science.gov (United States)

    Calmon, P; Gonze, M-A; Mourlon, Ch

    2015-10-01

    Following the Chernobyl accident, the scientific community gained numerous data on the transfer of radiocesium in European forest ecosystems, including information regarding the short-term redistribution of atmospheric fallout onto forest canopies. In the course of international programs, the French Institute for Radiological Protection and Nuclear Safety (IRSN) developed a forest model, named TREE4 (Transfer of Radionuclides and External Exposure in FORest systems), 15 years ago. Recently published papers on a Japanese evergreen coniferous forest contaminated by Fukushima radiocesium fallout provide interesting and quantitative data on radioactive mass fluxes measured within the forest in the months following the accident. The present study determined whether the approach adopted in the TREE4 model provides satisfactory results for Japanese forests or whether it requires adjustments. This study focused on the interception of airborne radiocesium by forest canopy, and the subsequent transfer to the forest floor through processes such as litterfall, throughfall, and stemflow, in the months following the accident. We demonstrated that TREE4 quite satisfactorily predicted the interception fraction (20%) and the canopy-to-soil transfer (70% of the total deposit in 5 months) in the Tochigi forest. This dynamics was similar to that observed in the Höglwald spruce forest. However, the unexpectedly high contribution of litterfall (31% in 5 months) in the Tochigi forest could not be reproduced in our simulations (2.5%). Possible reasons for this discrepancy are discussed; and sensitivity of the results to uncertainty in deposition conditions was analyzed.

  8. Radioactivity monitoring and import regulation of the contaminated foodstuffs in Japan following the Chernobyl nuclear power plant accident

    Energy Technology Data Exchange (ETDEWEB)

    Izumo, Yoshiro [Institute of Public Health, Tokyo (Japan)

    1997-03-01

    Radioactivity monitoring and import regulation of the contaminated foodstuffs executed by Minstry of Health and Welfare following the Chernobyl nuclear plant accident were reviewed as follows; (1) background of socio-psychological effects and environmental radioactivity leading to the regulation (to may 3, 1986); (2) intial intervention for imported foodstuffs in Japan (may 8, `86), and (3) in european countries (to may 31, `86), immediately after the Accident, respectively; (4) determination of the interim driven intervention level for radionuclides in imported foodstuffs (({sup 134}Cs + {sup 137}Cs): 370 Bq/Kg) and activation of the monitoring, (5) outline of the monitoring with elapsed time, number of foodstuffs monitored, number of foodstuffs exceeded radioactivity of the intervention level and re-exported; (6) guideline in international trade of radioactive contaminated foodstuffs adopted by CODEX Alimentarius Commission (FAO/WHO) and the intervention level recommended by ICRP following the Accident; (7) discussion for problems and scopes in future based on the results of monitoring. As the results, a number of imported foodstuffs (about 75,000 samples at present) has been monitored, 55 samples exceeding the interim intervention level were re-exported to each export`s country, and socio-psychological doubts for radioactive contamination of imported foodstuffs have been dispersed. In addition, problems for several factors based on calculation of the interim intervention level, radioactivity level of foodstuffs exceeding about 50 Bq/Kg as radiocesiums and necessity of monitoring for the other radionuclides in foods except radiocesiums were also discussed. (author)

  9. Thyroid Cancer in Ukrainian Population Groups Affected by the Chernobyl Accident

    Directory of Open Access Journals (Sweden)

    A Prysyazhnyuk

    2009-06-01

    Full Text Available The study goal was to investigate thyroid cancer morbidity in population groups affected by the Chernobyl catastrophe. The study period comprised 1994-2006 for clean-up workers and 1990-2006 for Chernobyl evacuees and residents of contaminated territories. A significant increase of thyroid cancer incidence was registered in all observed population groups. The most significant excess over the national level was identified in clean-up workers. This amounted to a factor of 5.9, while it was 5.5 for the evacuees and 1.7 for the residents. The highest thyroid cancer risk was observed in persons exposed to radioiodine in childhood and adolescence.

  10. [The genetic sequelae for plant populations of radioactive environmental pollution in connection with the Chernobyl accident].

    Science.gov (United States)

    Shevchenko, V A; Abramov, V I; Kal'chenko, V A; Fedotov, I S; Rubanovich, A V

    1996-01-01

    Populations of Arabidopsis thaliana (L.) Heynh., and Pinus sylvestris L., growing within 30 km of Chernobyl and Bryansk region have been analyzed for the frequency of embryonic lethal mutations on Arabidopsis and frequency of chlorophyll mutations and chromosome aberrations by pine. On pine also have been analyzed rate of mutations at enzyme loci in endosperms of seeds. Dose dependence of the value genetic damage on level of radioactive pollution was observed.

  11. Aerosol radioactivity record in Bratislava/Slovakia following the Fukushima accident--a comparison with global fallout and the Chernobyl accident.

    Science.gov (United States)

    Povinec, P P; Sýkora, I; Holý, K; Gera, M; Kováčik, A; Brest'áková, L

    2012-12-01

    Results of radioactivity measurements in Bratislava aerosols following the Fukushima accident showed that at least three radioactive plumes arrived to Bratislava as indicated by (131)I/(137)Cs activity ratios. When compared with the Chernobyl results available for the Bratislava station, the Fukushima radionuclide levels were almost five orders of magnitude lower, with the maximum values for (131)I and (137)Cs of 0.5 and 0.07 mBq/m(3), respectively. The (131)I and (137)Cs vs. (7)Be aerosol activity records showed that the increases in (131)I and (137)Cs activity concentrations were accompanied by (7)Be increases, indicating that both the horizontal and vertical transports of radionuclides were responsible for observed radionuclide concentrations. The (134)Cs/(137)Cs activity ratio was close to 1, as has also been reported by other investigators.

  12. Accident progression event tree analysis for postulated severe accidents at N Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Wyss, G.D.; Camp, A.L.; Miller, L.A.; Dingman, S.E.; Kunsman, D.M. (Sandia National Labs., Albuquerque, NM (USA)); Medford, G.T. (Science Applications International Corp., Albuquerque, NM (USA))

    1990-06-01

    A Level II/III probabilistic risk assessment (PRA) has been performed for N Reactor, a Department of Energy (DOE) production reactor located on the Hanford reservation in Washington. The accident progression analysis documented in this report determines how core damage accidents identified in the Level I PRA progress from fuel damage to confinement response and potential releases the environment. The objectives of the study are to generate accident progression data for the Level II/III PRA source term model and to identify changes that could improve plant response under accident conditions. The scope of the analysis is comprehensive, excluding only sabotage and operator errors of commission. State-of-the-art methodology is employed based largely on the methods developed by Sandia for the US Nuclear Regulatory Commission in support of the NUREG-1150 study. The accident progression model allows complex interactions and dependencies between systems to be explicitly considered. Latin Hypecube sampling was used to assess the phenomenological and systemic uncertainties associated with the primary and confinement system responses to the core damage accident. The results of the analysis show that the N Reactor confinement concept provides significant radiological protection for most of the accident progression pathways studied.

  13. Accident analysis of heavy water cooled thorium breeder reactor

    Science.gov (United States)

    Yulianti, Yanti; Su'ud, Zaki; Takaki, Naoyuki

    2015-04-01

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The power reactor has a peak value before reactor has new balance condition

  14. Thermal-hydraulic modeling of reactivity accidents in MTR reactors

    Directory of Open Access Journals (Sweden)

    Khater Hany

    2006-01-01

    Full Text Available This paper describes the development of a dynamic model for the thermal-hydraulic analysis of MTR research reactors during a reactivity insertion accident. The model is formulated for coupling reactor kinetics with feedback reactivity and reactor core thermal-hydraulics. To represent the reactor core, two types of channels are considered, average and hot channels. The developed computer program is compiled and executed on a personal computer, using the FORTRAN language. The model is validated by safety-related benchmark calculations for MTR-TYPE reactors of IAEA 10 MW generic reactor for both slow and fast reactivity insertion transients. A good agreement is shown between the present model and the benchmark calculations. Then, the model is used for simulating the uncontrolled withdrawal of a control rod of an ETRR-2 reactor in transient with over power scram trip. The model results for ETRR-2 are analyzed and discussed.

  15. Monitoring of Individual Doses of Populations Residing in the Territories Contaminated after Chernobyl Accident

    Energy Technology Data Exchange (ETDEWEB)

    Chumak, V.V.; Likhtarev, I.A.; Pavlenko, J.V. [Acad of Medical Science of Ukraine, Kiev (Ukraine)

    1999-07-01

    To provide instrumental validation of radioecological dosimetric models used for estimation of external doses to the Chernobyl population, about 1000 direct dose measurements were conducted in 1996-1997 in 54 settlements in contaminated territories of Ukraine. The areas covered by the measurements have {sup 137}Cs contamination density ranging from 55 to 491 kBq.m{sup -2}. Individual dose measurements were conducted using standard LiF dosemeters, type Harshaw 8814 (TLD-100), and automated TLD system Harshaw 8800. Relatively low contamination and, thus, an unfavourable 'Chernobyl/natural background' dose ratio, called for sophisticated analysis of experimental results. Linear regression of dose relative to {sup 137}Cs contamination density which was conducted in two different ways provided consistent results. Annual background dose, as derived from the results of individual dose measurements, is about 1.1 mSv per annum; the Chernobyl related component is expressed by the rate of 1.24-1.3 {mu}Sv per kBq.m{sup -2} per annum. These results are in reasonable agreement with somewhat conservative modelling parameters which are assumed to be 1.91 {mu}Sv per kBq.m{sup -2} per annum for the case of the rural population. (author)

  16. Report of the US Department of Energy's team analyses of the Chernobyl-4 Atomic Energy Station accident sequence

    Energy Technology Data Exchange (ETDEWEB)

    1986-11-01

    In an effort to better understand the Chernobyl-4 accident of April 26, 1986, the US Department of Energy (DOE) formed a team of experts from the National Laboratories including Argonne National Laboratory, Brookhaven National Laboratory, Oak Ridge National Laboratory, and Pacific Northwest Laboratory. The DOE Team provided the analytical support to the US delegation for the August meeting of the International Atomic Energy Agency (IAEA), and to subsequent international meetings. The DOE Team has analyzed the accident in detail, assessed the plausibility and completeness of the information provided by the Soviets, and performed studies relevant to understanding the accident. The results of these studies are presented in this report.

  17. On the reduction of internal radiation doses due to the ingestion of CS-137 in areas contaminated by the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Hill, P.; Schlager, M.; Vogel, V.; Hille, R. [Forschungszentrum Julich GmbH, Julich (Germany); Nesterenko, A.V.; Nesterenko, V.B. [BELRAD, Minsk, (Belarus)

    2006-07-01

    After the Chernobyl reactor accident wide areas of Belarus have been contaminated with radioactive fallout. The verification and documentation of the long-term development of radiation doses is still going on. A population group of special concern are the children living in contaminated regions. Of the two million Belarussian children, approximately 80000 live in regions contaminated after the Chernobyl accident by a {sup 137}Cs deposition of more than 185 kBq/m. A German-Belarussian project is investigating radiation doses of children in those regions since several years. In a recent paper [1] it has been shown, that the annual dose limit of 1 mSv/a is still exceeded in some cases, essentially due to high body burdens of Cs -137 as indicated by screening measurements with portable incorporation monitors. Means of dose reduction such as remediation of agricultural land had been investigated in the past and generally already contribute to a reduction of food contamination. Also the use of clean food and the control of food contamination has generally proven its effectiveness and the latter is exercised by official authorities and private initiatives. In situations, where this is not sufficient, the clarification of the usefulness of additional means, such as the cure-like application of pectin preparations, makes sense. A dose lowering effect is presumed by Belarussian and Ukrainian scientists. In the framework of the present German-Belarussian project special attention is given to the cure-like application of a Belarussian pectin-preparation (Vitapect). Vitapect consists of apple pectins with added vitamins, mineral nutrients and flavour substances. It is currently in use in Belarus in accordance with legal regulations and licensed by the Belarus authorities. In a placebo-controlled double-blind study, several groups of contaminated children were treated with Vitapect for a two -week period during their stay in a sanatorium. For comparison the same number of

  18. Radiation conditions in the Oryol region territory impacted by radioactive contamination caused by the Chernobyl NPP accident

    Directory of Open Access Journals (Sweden)

    G. L. Zakharchenko

    2016-01-01

    Full Text Available Research objective is retrospective analysis of radiation conditions in the Oryol region during 1986- 2015 and assessment of efficacy of the carried out sanitary and preventive activities for population protection against radiation contamination caused by the Chernobyl NPP accident.Article materials were own memoirs of events participants, analysis of federal state statistic surveillance forms 3-DOZ across the Oryol region, f-35 “Data on patients with malignant neoplasms, f-12 “Report on MPI activities”. Risk assessment of oncological diseases occurrence is carried out on the basis of AAED for 1986- 2014 using the method of population exposure risk assessment due to long uniform man-made irradiation in small doses. Results of medical and sociological research of genetic, environmental, professional and lifestyle factors were obtained using the method of cancer patients’ anonymous survey. Data on "risk" factors were obtained from 467 patients hospitalized at the Budgetary Health Care Institution of the Oryol region “Oryol oncology clinic”; a specially developed questionnaire with 60 questions was filled out.The article employs the method of retrospective analysis of laboratory and tool research and calculation of dose loads on the Oryol region population, executed throughout the whole period after the accident.This article provides results of the carried out laboratory research of foodstuff, environment objects describing the radiation conditions in the Oryol region since the first days after the Chernobyl NPP accident in 1986 till 2015.We presented a number of activities aimed at liquidation of man-caused radiation accident consequences which were developed and executed by the experts of the Oryol region sanitary and epidemiology service in 1986-2015. On the basis of the above-stated one may draw the conclusions listed below. Due to interdepartmental interaction and active work of executive authorities in the Oryol region, the

  19. Revised accident source terms for light-water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Soffer, L. [Nuclear Regulatory Commission, Washington, DC (United States)

    1995-02-01

    This paper presents revised accident source terms for light-water reactors incorporating the severe accident research insights gained in this area over the last 15 years. Current LWR reactor accident source terms used for licensing date from 1962 and are contained in Regulatory Guides 1.3 and 1.4. These specify that 100% of the core inventory of noble gases and 25% of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental iodine. These assumptions have strongly affected present nuclear air cleaning requirements by emphasizing rapid actuation of spray systems and filtration systems optimized to retain elemental iodine. A proposed revision of reactor accident source terms and some im implications for nuclear air cleaning requirements was presented at the 22nd DOE/NRC Nuclear Air Cleaning Conference. A draft report was issued by the NRC for comment in July 1992. Extensive comments were received, with the most significant comments involving (a) release fractions for both volatile and non-volatile species in the early in-vessel release phase, (b) gap release fractions of the noble gases, iodine and cesium, and (c) the timing and duration for the release phases. The final source term report is expected to be issued in late 1994. Although the revised source terms are intended primarily for future plants, current nuclear power plants may request use of revised accident source term insights as well in licensing. This paper emphasizes additional information obtained since the 22nd Conference, including studies on fission product removal mechanisms, results obtained from improved severe accident code calculations and resolution of major comments, and their impact upon the revised accident source terms. Revised accident source terms for both BWRS and PWRS are presented.

  20. Contamination of North- and Baltic Sea as a result of the accident of Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Nies, H.; Wedekind, C.

    1987-01-01

    The input from 'Chernobyl' can be distinguished from other sources of artificial radionuclides, such as the reprocessing plants at La Hague and Sellafield, by its characteristic nuclide spectrum. The input occurred to quite different strength of activity in the different areas of the North Sea and the Baltic Sea; a rapid vertical dilution within the water column resulted in a rapid decrease of the initial activity concentration. The sediments are contaminated by the vertical transport of sinking suspended particulate matter, which adsorb the activity from the surrounding water.

  1. Chernobyl, 16 years later; Tchernobyl, 16 ans apres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    This document on the Chernobyl site evolution is constituted around four main questions. What about the future of the Chernobyl site, the damaged reactor and the ''sarcophagus'' constructed around the reactor? What about the sanitary consequences of the accident on the liquidators asked to blot out the radiation and the around people exposed to radiation? What about the contaminated land around the power plant and their management? Concerning the France, what were the ''radioactive cloud'' sanitary consequences? (A.L.B.)

  2. MORBIDITY AND MORTALITY AMONG EMERGENCY WORKERS OF THE CHERNOBYL ACCIDENT: ASSESSMENT OF RADIATION RISKS FOR THE FOLLOW-UP PERIOD OF 1992-2008

    Directory of Open Access Journals (Sweden)

    V. K. Ivanov

    2011-01-01

    Full Text Available Morbidity and mortality among emergency workers of the Chernobyl accident for the follow- up period of 199Morbidity and mortality among the emergency workers of the Chernobyl accident for the follow-up period of 1992-2008 is analyzed in the article. The cohort consists of 47141 emergency workers of 1986-1987. Radiation risks for cancer morbidity (ERR/Gy is 0.76; 95% CI: 0.19; 1.42, p-value=0008 and cancer mortality (ERR/Gy is 0.95; 95% CI: 0.19; 1.89, p-value=0.01 are statistically significant. Radiation risk for vascular diseases is assessed as well.

  3. Iodine-131 dose dependent gene expression in thyroid cancers and corresponding normal tissues following the Chernobyl accident.

    Directory of Open Access Journals (Sweden)

    Michael Abend

    Full Text Available The strong and consistent relationship between irradiation at a young age and subsequent thyroid cancer provides an excellent model for studying radiation carcinogenesis in humans. We thus evaluated differential gene expression in thyroid tissue in relation to iodine-131 (I-131 doses received from the Chernobyl accident. Sixty three of 104 papillary thyroid cancers diagnosed between 1998 and 2008 in the Ukrainian-American cohort with individual I-131 thyroid dose estimates had paired RNA specimens from fresh frozen tumor (T and normal (N tissue provided by the Chernobyl Tissue Bank and satisfied quality control criteria. We first hybridized 32 randomly allocated RNA specimen pairs (T/N on 64 whole genome microarrays (Agilent, 4×44 K. Associations of differential gene expression (log(2(T/N with dose were assessed using Kruskall-Wallis and trend tests in linear mixed regression models. While none of the genes withstood correction for the false discovery rate, we selected 75 genes with a priori evidence or P kruskall/P trend <0.0005 for validation by qRT-PCR on the remaining 31 RNA specimen pairs (T/N. The qRT-PCR data were analyzed using linear mixed regression models that included radiation dose as a categorical or ordinal variable. Eleven of 75 qRT-PCR assayed genes (ACVR2A, AJAP1, CA12, CDK12, FAM38A, GALNT7, LMO3, MTA1, SLC19A1, SLC43A3, ZNF493 were confirmed to have a statistically significant differential dose-expression relationship. Our study is among the first to provide direct human data on long term differential gene expression in relation to individual I-131 doses and to identify a set of genes potentially important in radiation carcinogenesis.

  4. Simulation of reactivity accidents utilizing the IGR reactor

    Energy Technology Data Exchange (ETDEWEB)

    Asmolov, V.G.; Tukhvatulin, Sh.T.; Cherepnin, Yu.S.

    1994-12-31

    The Impulse Graphite Reactor (IGR) is located on the Semipalatinsk nuclear test site - 50 km southwest of the town of Kurchatov (Semipalatinsk-21), Republic of Kazakhstan. The reactor has been in operation since January 8, 1961. One of the principal objectives of the IGR program has been to obtain direct experimental data on the behavior of fuel elements and reactor components under accident conditions. Measurements include determination of threshold destructive characteristics. These data are then used to develop and verify the computational models used to analyze accident consequences. The IGR has a cubical core assembled from uranium-loaded graphite blocks. The core is reflected with the same graphite blocks but without the uranium loading. The reactor has a negative temperature coefficient and is operated by a system of vertical control and safety rods. Two vertical chambers, one within the reactor core and one at the core-reflector interface, provide two channels to carry out experimental studies of materials and systems under accident conditions. The central channel can accommodate hardened capsules that allow melting and destruction of fuel assemblies. The IGR parameters are provided.

  5. Summary of the consequences for the environment of the Chernobyl accident; Synthese sur les consequences environnementales de l`accident de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Ciffroy, P.

    1996-08-01

    The main conclusions on the environmental consequences of the Chernobyl accident in the former Soviet Union can be summarised as follows: the long term radioactive contamination of the environment can essentially be put down to Cs and Sr and, to a lesser degree, transuranic elements. In the short term, the radioactive iodine fall-out plays a fundamental role; in the countries of the former Soviet Union, it is estimated that 29,300 and 10,200 km{sup 2} of the surface area of the land are respectively contaminated by over 185 and 555 kBq.m{sup -2}. Approximately 1,064,000 people live in areas contaminated by more than 185 kBq.m{sup -2}; acute radioactive fall-out effects have occurred in the 30 km exclusion zone, essentially witnessed by the death of numerous conifers. On average, it will take about twenty years for half the Cs to disappear from the top 10 cm of soil; the level of contamination of food products varies greatly according to soil type. However, we can consider that milk, berries and mushrooms were the most critical foods in the years immediately following the accident and that some of the agricultural counter-measures taken have proved very useful in containing the contamination of food products. Because of the massive iodine leakage, the worst affected organ in the body during the months following the accident was the thyroid gland. In the months following the accident, the presence of radioactive elements on the surface of vegetables which were subsequently eaten proved to be the main source of human contamination; after a rapid fall off in external dose received by the population during the first year, it is now decreasing much more slowly. This phenomenon is mainly due to the very long-life of the radioactive caesium in the soil; approximately 90 % of the total internal dose for the 70 years following the accident have already been received by the local population. The external dose level will be reduced fairly slowly and we can assess that

  6. Preliminary accident analysis of Flexblue® underwater reactor

    Directory of Open Access Journals (Sweden)

    Haratyk Geoffrey

    2015-01-01

    Full Text Available Flexblue® is a subsea-based, transportable, small modular reactor delivering 160 MWe. Immersion provides the reactor with an infinite heat sink – the ocean – around the metallic hull. The reference design includes a loop-type PWR with two horizontal steam generators. The safety systems are designed to operate passively; safety functions are fulfilled without operator action and external electrical input. Residual heat is removed through four natural circulation loops: two primary heat exchangers immersed in safety tanks cooled by seawater and two emergency condensers immersed in seawater. In case of a primary piping break, a two-train safety injection system is actuated. Each train includes a core makeup tank, an accumulator and a safety tank at low pressure. To assess the capability of these features to remove residual heat, the reactor and its safety systems have been modelled using thermal-hydraulics code ATHLET with conservative assumptions. The results of simulated transients for three typical PWR accidents are presented: a turbine trip with station blackout, a large break loss of coolant accident and a small break loss of coolant accident. The analyses show that the safety criteria are respected and that the reactor quickly reaches a safe shutdown state without operator action and external power.

  7. Chernobyl bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Carr, F. Jr.; Mahaffey, J.A.

    1989-09-01

    The purpose of the DOE/OHER Chernobyl Database project is to create and maintain an information system to provide usable information for research studies related to the nuclear accident. The system is the official United States repository for information about the Chernobyl accident and its consequences, and currently includes an extensive bibliography and diverse radiological measurements with supporting information. PNL has established two resources: original (not summarized) measurement data, currently about 80,000 measurements, with ancillary information; and about 2,200 bibliographic citations, some including abstracts. Major organizations that have contributed radiological measurement data include the Washington State Department of Social and Health Services; United States Environmental Protection Agency (domestic and foreign data); United States Nuclear Regulatory Commission; Stone Webster; Brookhaven National Laboratory; Commissariat A L'energie Atomique in France; Ministry of Agriculture, Fisheries, and Food in the United Kingdom; Japan National Institute of Radiological Sciences; and the Finnish Centre For Radiation and Nuclear Safety (STUK). Scientists in Australia, Austria, Belgium, Canada, China, Denmark, England, Federal Republic of Germany, Finland, France, Ireland, Italy, Japan, the Netherlands, Romania, Scotland, Spain, Sweden, Switzerland, United States, Wales, and Yugoslavia have made contributions. Bibliographic materials have been obtained from scientists in the above countries that have replied to requests. In addition, literature searches have been conducted, including a search of the DOE Energy Database. The last search was conducted in January, 1989. This document lists the bibliographic information in the DOE/OHER Chernobyl Database at the current time.

  8. Chernobyl, 12 years later; Tchernobyl, douze ans apres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-04-01

    This report draws an account of the consequences of Chernobyl accident 12 years after the disaster. It is made up of 7 chapters whose titles are: (1) Some figures about Chernobyl accident, (2) The Chernobyl nuclear power plant, (3) Sanitary consequences of Chernobyl accident, (4) The management of contaminated lands, (5) The impact in France of Chernobyl fallout, (6) The Franco-German cooperation, and (7) Glossary.

  9. Yearly variation of spontaneous somatic mutation frequency in the stamen hairs of Tradescantia clone KU 9 grown outdoors, which showed a significant increase after the Chernobyl accident.

    Science.gov (United States)

    Ichikawa, S; Nakano, A; Kenmochi, M; Yamamoto, I; Murai, M; Takahashi, E; Yamaguchi, A; Watanabe, K; Tomiyama, M; Sugiyama, K; Yogo, A; Yazaki, T; Okumura, M; Shima, N; Satoh, M; Yoshimoto, M; Xiao, L Z

    1996-02-01

    Scoring of spontaneous somatic pink mutation frequency in the stamen hairs of Tradescantia clone KU 9, a heterozygote for flower color (blue/pink; the blue color being dominant), was carried out for 11 years on plants grown outdoors, during the period of May 11-31 (for 3 weeks) in every year from 1982 to 1992. Weekly and yearly variations of the spontaneous mutation frequency were observed, and such variations could mostly be correlated to the difference in temperature. That is, the mutation frequency was generally higher in the weeks and years when the temperature was relatively low, showing the strongest negative correlation with the average minimum temperature. The variations were also correlated to the diurnal temperature difference, the mutation frequency being higher with larger diurnal temperature difference in general. However, the mutation frequency observed in 1986 was exceptionally higher than that expected from the temperature for this year, and was very significantly higher than for other years. The scoring of mutation frequency was thus continued in 1986 for an additional 4 weeks (June 1-28), and it was confirmed that such higher mutation frequencies lasted for 6 weeks in total. The exceptionally high mutation frequency seemed to be related to the radioactive fallout which occurred in early to mid May of 1986, even in Japan, after the serious nuclear reactor accident at Chernobyl, and also to the biological concentrations of radioactive nuclides which subsequently occurred, although it was difficult to conclude this definitely. The mutation frequency in 1987 was second highest, and was also significantly higher than the lowest mutation frequency observed in 1990.

  10. Metrological data and risk assessment in France during the Chernobyl accident. Historical statement; Donnees metrologiques et evaluation des risques en France lors de l'accident de Tchernobyl (26 avril 1986). Mise au point historique

    Energy Technology Data Exchange (ETDEWEB)

    Galle, P. [Ecole Nationale Veterinaire d' Alfort, Lab. de Physique et Chimie, 94 - Maisons Alfort (France); Paulin, R. [Groupe de Recherche en Radiotoxicologie, GRT, 13 - Marseille (France); Coursaget, J. [Hopital de l' Hotel Dieu, Service de Medecine Nucleaire, 75 - Paris (France)

    2003-08-01

    Metrological data and risk assessment in France during the Chernobyl accident. Historical statement. The authors indicate the origin of the data used by the French Public Health Authority in 1986 to estimate the risk of the radioactive fall out following the Chernobyl accident. The technical means developed in order to establish this data, and the precedent experience gained, are described. The principal results are given. The terms of the 28 May 1986 note to the Academy of Sciences by R. Latarjet, which concluded that the low level of this fallout did not justify any countermeasure, except the control of the imported food, are confirmed. Rational dispositions are required in order to improve the information of the population, referring to the Swedish model, which involves the intervention of the medical staff specialized in radio-toxicology, radio-pathology, nuclear medicine, and especially trained. To cite this article: P. Galle et al., C. R. Biologies 326 (2003). (authors)

  11. Scientists help children victims of the Chernobyl reactor accident. Report on project phase 1 and annex to the report on phase 1: 1.4.1993 - 31.3.1996; Wissenschaftler helfen Tschernobyl-Kindern. Bericht der Phase I und Anhang zum Bericht der Phase I: 1.4.1993 - 31.3.1996

    Energy Technology Data Exchange (ETDEWEB)

    Reiners, C. [Wuerzburg Univ. (Germany). Klinik und Poliklinik fuer Strahlentherapie; Streffer, C. [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Medizinische Strahlenbiologie; Voigt, G.; Paretzke, H.G. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Heinemann, G. [Preussische Elektrizitaets-AG (Preussenelektra), Hannover (Germany); Pfob, H. [Badenwerk AG, Karlsruhe (Germany)

    1997-12-01

    The bilateral project of Belarus and Germany was commissioned on 1.04.1993 and is placed under the scientific guidance of the Gemeinschaftsausschuss Strahlenforschung. In the framework of the project part devoted to ``therapy and medical training``, covering the period from 1.04.1993 until 31.03.1996, all in all 99 children from Belarus suffering from advanced-stage tumors of the thyroid received a special radio-iodine therapy in Germany. In about 60% of the children complete removal of the tumor was achieved. Another task of the project was to train over the reporting period 41 doctors and physicists from Belarus in the fields of nuclear medical diagnostic evaluation and therapy of thyroid tumors. The project part ``biological dosimetry`` was to investigate the role of micronuclei in peripheral lymphocytes, and whether their presence in the lymphocytes permits to derive information on the radiation dose received even several years after the reactor accident. The scientists also exmained the role of the micronuclei in follow-up examinations of the radio-iodine therapy. Further studies used the relatively large number of tumors in the children, as compared to the literature available until the accident, to examine whether there are specific mutation patterns to be found in tumot suppressor genes (p-53) in thyroid tumors which might be used as indicators revealing radiation-induced onset of tumor growth. The project part ``retrospective dosimetry and risk analysis`` was in charge of detecting information answering the question of whether the release of I-131, suspected to be critical nuclide, really was the cause of enhanced incidence of thyroid tumors in the children. The project part ``coordination and examination center at Minsk`` was to establish and hold available the support required by the GAST project participants. (orig./CB) [Deutsch] Am 01.04.1993 wurde ein bilateral weissrussisch-deutsches Projekt begonnen, das unter der wissenschaftlichen Begleitung des

  12. Design requirements for innovative homogeneous reactor, lesson learned from Fukushima accident

    Science.gov (United States)

    Arbie, Bakri; Pinem, Suryan; Sembiring, Tagor; Subki, Iyos

    2012-06-01

    The Fukushima disaster is the largest nuclear accident since the 1986 Chernobyl disaster, but it is more complex as multiple reactors and spent fuel pools are involved. The severity of the nuclear accident is rated 7 in the International Nuclear Events Scale. Expert said that "Fukushima is the biggest industrial catastrophe in the history of mankind". According to Mitsuru Obe, in The Wall Street Journal, May 16th of 2011, TEPCO estimates the nuclear fuel was exposed to the air less than five hours after the earthquake struck. Fuel rods melted away rapidly as the temperatures inside the core reached 2800 C within six hours. In less than 16 hours, the reactor core melted and dropped to the bottom of the pressure vessel. The information should be evaluated in detail. In Germany several nuclear power plant were shutdown, Italy postponed it's nuclear power program and China reviewed their nuclear power program. Different news come from Britain, in October 11, 2011, the Safety Committee said all clear for nuclear power in Britain, because there are no risk of strong earthquake and tsunami in the region. Due to this severe fact, many nuclear scientists and engineer from all over the world are looking for a new approach, such as homogeneous reactor which was developed in Oak Ridge National Laboratory in 1960-ies, during Dr. Alvin Weinberg tenure as the Director of ORNL. The paper will describe the design requirement that will be used as the basis for innovative homogeneous reactor. Innovative Homogeneous Reactor is expected to reduce core melt by two decades (4), since the fuel is intermix homogeneously with coolant and secondly we eliminate the used fuel rod which need to be cooled for a long period of time. In order to be successful for its implementation of the innovative system, testing and validation, three phases of development will be introduced. The first phase is Low Level Goals is really the proof of concept;the Medium Level Goal is Technical Goalsand the High

  13. Accident scenarios of the TRIGA Mark II reactor in Vienna

    Energy Technology Data Exchange (ETDEWEB)

    Villa, Mario, E-mail: mvilla@ati.ac.a [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria); Haydn, Markus [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria); Steinhauser, Georg, E-mail: georg.steinhauser@ati.ac.a [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria); Boeck, Helmuth [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria)

    2010-12-15

    The safety report of the TRIGA Mark II reactor in Vienna includes three accident scenarios and their deterministic dose consequences to the environment. The destruction of the cladding of the most activated fuel element, the destruction of all fuel elements and a plane crash were considered scenarios in that report. The calculations were made in 1978 with the software program named STRISK. In this paper, the program package PC Cosyma was applied on the TRIGA Mark II reactor in Vienna and the deterministic consequences of the scenarios to the environment were updated. The fission product inventories of all fuel elements were calculated with ORIGEN2. To get meteorological data of the atmospheric condition around the release area, a weather station was installed. The release parameters were taken from the safety report or were replaced by worst case parameters. This paper focuses on two accident scenarios: the destruction of the cladding of the fuel element with the highest activity content and the case of a large plane crash. The current accident scenarios show good agreement with the calculations from 1978, hence no technical modifications in the safety report of the TRIGA reactor Vienna were necessary. Even in the very worst case scenario - complete destruction of all fuel elements in a large plane crash - the expected doses in the Atominstitut's neighborhood remain moderate.

  14. SUBSTANTIAL AND STRUCTURAL COMPONENTS OF THE MENTAL STATUS OF THE PERSONS WHO HAVE RECEIVED SMALL DOSES OF RADIATION DURING LIGUIDATION OF THE ACCIDENT AT THE CHERNOBYL NUCLEAR POWER PLANT

    Directory of Open Access Journals (Sweden)

    О. V. Baranova

    2012-01-01

    Full Text Available In the article the peculiarities of ideas about the catastrophe at the Chernobyl nuclear power plant disaster at the persons who have suffered from radiation during liquidation of the accident’s consequences. View of the accident was considered as a key element of a person’s mind, in particular the adaptive. There were 30 persons, who took part in the research – participants of Chernobyl disaster’s liquidation, veterans of division of an extra risk. The subjective assessment of mental health at persons who survived in Chernobyl disaster was defined; personal properties of victims were revealed; interrelations between personal properties and subjective assessment of mental health were established. It is possible to assume that in process of moving away from the moment of the accident the content of view of Chernobyl disaster shows concentration of the person on experience of mental health and the personal potential.

  15. Field studies on the behaviour of radiocaesium in agricultural environments after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, K.

    1996-05-01

    This thesis deals with the occurrence of Chernobyl {sup 137}Cs and {sup 134}Cs in cultivated, semi-natural and natural agricultural areas of five Swedish counties. The investigations were carried out under field conditions 1986 to 1995 on farms where transfer to grass and milk during the first years were high. Vertical migration rate in soil profiles, the practical value of countermeasures to reduce transfer to feed and food and the impact of passing time were important aims for the study. The transfer of Cs was higher on permanent pasture than on temporary grassland and much lower to barley grain. Stubble and grass swards kept Cs available for transfer to grass. High organic matter contents in the surface soil also caused high transfer during a lag period of some years. Soil texture, grass sward, K-fertilization and growth dilution explained the variation in Cs transfer and its reduction rate. A case study on transfer of Cs to vegetation and to grazing lambs was made on a mountain farm. High transfer to vegetation was found, 510-2260 Bq/kg d.w.. Mean transfer soil to plant (TFg,m{sup 2}/kg) was 67 and plant to muscle 0.7 during 1990-1993. The effect of K-fertilization on soil-plant transfer was studied on 15 soils. A dose of 100 to 200 kg/ha K decreased the transfer on sandy soils with a factor of up to 10. Liming was effective on soils that were originally low in pH. Adding zeolite on the surface of pastures did not reduce the root uptake of Cs. Ploughing down the contaminated surface was effective in reducing the transfer. Downward migration of Cs was usually less on mineral soils than or organic or podsolized soils. 68 refs, 9 figs, 13 tabs.

  16. A probabilistic dispersion model applied to the long-range transport of radionuclides from the Chernobyl accident

    DEFF Research Database (Denmark)

    Lauritzen, B.; Mikkelsen, T.

    1999-01-01

    . A corresponding effective deposition length for caesium, R-Cs, defined las the effective distance from Chernobyl to where the aerosols have been deposited, is found to be R-Cs approximate to 1000 km. From the observations of the regional variability of the Chernobyl fallout a simple probabilistic assessment...

  17. Chernobyl - 20 years and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Lacronique, J.F. [Institut de Radioprotection et de Surete Nucleaire, 92 - Fontenay-aux-Roses (France); Deconinck, F.; Govaerts, P.; Eggermont, C. [SCK-CEN - Studiecentrum voor Kernenergie, Centre d' Etude de l' Energie Nucleaire, Mol (Belgium); Cort, M. de [Institute for Environment and Sustainability, DG JRC EC (Italy); Joulia, J.P. [EuropeAid Co-operation Office, EC, Brussels (Belgium); Dal, A.H.; Balonov, M. [International Atomic Energy Agency (IAEA), Vienna (Austria); Kenigsberg, J. [Commission on Radiation protection, council of ministry (Belarus); Hindie, E. [Universites Paris, 75 (France); Havenaar, M. [Amsterdam Univ. (Netherlands)

    2006-07-01

    In commemoration of the Chernobyl accident 20 years ago, the French society for radiation protection (S.F.R.P.) and the Belgian society for radiation protection (B.V.S.A.B.R.) organise jointly a one day colloquium in Brussels. This colloquium is divided in two parts: the first one concerns the technical and organisational aspects of the accident with the scenario and its global impact, the international environmental radioactivity information exchange through the Chernobyl experience, the European Union (E.U.) assistance to mitigate the Chernobyl accident consequences, the crisis communication and management and the lessons learned from them; the second part is devoted to the medical and humanitarian aspects through the thyroid cancers after Chernobyl accident, the health effects in the European Union (E.U.) and the psychological factors affecting health after the Chernobyl disaster. (N.C.)

  18. Chernobyl, 13 years after; Tchernobyl, 13 ans apres

    Energy Technology Data Exchange (ETDEWEB)

    Regniault-Lacharme, Mireille; Metivier, Henri [Inst. de Protection et de Surete Nucleaire, CEA Centre d' Etudes de Fontenay-aux-Roses, 92 (France)

    1999-04-01

    This is an annual report, regularly issued by IPSN, that presents the ecological and health consequences of the Chernobyl Nuclear Accident. The present status of the Chernobyl Nuclear Plant, which Ukraine engaged to stop definitively in year 2000, is summarized. The only reactor unit now in operation is Chernobylsk-3 Reactor which poses two safety questions: evolution of cracks in part of the tubing and behaviour of the pressure tubes. Although, some improvements in the RBMK reactor types were introduced, problems remain that make IPSN to stress the requirement of stopping this NPP completely. In the contaminated territories surrounding Chernobyl incidence rate of infant thyroid cancers continues to grow, reaching values 10 to 100 times higher than the natural rate. In France the IPSN analyzed 60,000 records carried out in 17 sites during May 1986 and April 1989. It was estimated that the individual dose received during 60 years (1986-2046) by the inhabitants of the most affected zone (eastern France) is lower than 1.5 mSv, a value lower than 1% of the natural cosmic and telluric radioactivity exposure for the same period. For the persons assumed to live in the most attacked forests (from eastern France) and nourishing daily with venison and mushrooms the highest estimate is 1 mSv a year. Concerning the 'hot spots', identified in mountains by IPSN and CRIIRAD, the doses received by excursionists are around 0.015 mSv. For an average inhabitant of the country the dose piled up in the thyroid due to iodine-131 fallout is estimated to 0.5-2 mSv for an adult and 6.5-16 mSv for an infant. These doses are 100 to 1000 times lower than the ones to which the infants living in the neighbourhood of Chernobyl are exposed to. The contents of the report is displayed in the following six chapters: 1. Chernobyl in some figures; 2. The 'sarcophagus' and the reactors of the Chernobyl NPP; 3. Health consequences of the Chernobyl accident;. 4. The impact of

  19. Simulation of {sup 137}Cs transport and deposition after the Chernobyl Nuclear Power Plant accident and radiological doses over the Anatolian Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Simsek, V.; Pozzoli, L.; Unal, A.; Kindap, T., E-mail: kindap@itu.edu.tr; Karaca, M.

    2014-11-15

    The Chernobyl Nuclear Power Plant (CNPP) accident occurred on April 26 of 1986, it is still an episode of interest, due to the large amount of radionuclides dispersed in the atmosphere. Caesium-137 ({sup 137}Cs) is one of the main radionuclides emitted during the Chernobyl accident, with a half-life of 30 years, which can be accumulated in humans and animals, and for this reason the impacts on population are still monitored today. One of the main parameters in order to estimate the exposure of population to {sup 137}Cs is the concentration in the air, during the days after the accident, and the deposition at surface. The transport and deposition of {sup 137}Cs over Europe occurred after the CNPP accident has been simulated using the WRF-HYSPLIT modeling system. Four different vertical and temporal emission rate profiles have been simulated, as well as two different dry deposition velocities. The model simulations could reproduce fairly well the observations of {sup 137}Cs concentrations and deposition, which were used to generate the ‘Atlas of Caesium deposition on Europe after the Chernobyl accident’ and published in 1998. An additional focus was given on {sup 137}Cs deposition and air concentrations over Turkey, which was one of the main affected countries, but not included in the results of the Atlas. We estimated a total deposition of 2–3.5 PBq over Turkey, with 2 main regions affected, East Turkey and Central Black Sea coast until Central Anatolia, with values between 10 kBq m{sup −2} and 100 kBq m{sup −2}. Mean radiological effective doses from simulated air concentrations and deposition has been estimated for Turkey reaching 0.15 mSv/year in the North Eastern part of Turkey, even if the contribution from ingestion of contaminated food and water is not considered, the estimated levels are largely below the 1 mSv limit indicated by the International Commission on Radiological Protection. - Highlights: • Chernobyl Nuclear Power Plant accident

  20. Analysis of credible accidents for Argonaut reactors. Report for October 1980-April 1981

    Energy Technology Data Exchange (ETDEWEB)

    Hawley, S.C.; Kathren, R.L.; Robkin, M.A.

    1981-04-01

    Five areas of potential accidents have been evaluated for the Argonaut-UTR reactors. They are: insertion of excess reactivity, catastrophic rearrangement of the core, explosive chemical reaction, graphite fire, and a fuel-handling accident.

  1. Reconstruction of radiation doses in a case-control study of thyroid cancer following the Chernobyl accident.

    Science.gov (United States)

    Drozdovitch, Vladimir; Khrouch, Valeri; Maceika, Evaldas; Zvonova, Irina; Vlasov, Oleg; Bratilova, Angelica; Gavrilin, Yury; Goulko, Guennadi; Hoshi, Masaharu; Kesminiene, Ausrele; Shinkarev, Sergey; Tenet, Vanessa; Cardis, Elisabeth; Bouville, André

    2010-07-01

    A population-based case-control study of thyroid cancer was carried out in contaminated regions of Belarus and Russia among persons who were exposed during childhood and adolescence to fallout from the Chernobyl accident. For each study subject, individual thyroid doses were reconstructed for the following pathways of exposure: (1) intake of 131I via inhalation and ingestion; (2) intake of short-lived radioiodines (132I, 133I, and 135I) and radiotelluriums (131mTe, 132Te) via inhalation and ingestion; (3) external dose from radionuclides deposited on the ground; and (4) ingestion of 134Cs and 137Cs. A series of intercomparison exercises validated the models used for reconstruction of average doses to populations of specific age groups as well as of individual doses. Median thyroid doses from all factors for study subjects were estimated to be 0.37 and 0.034 Gy in Belarus and Russia, respectively. The highest individual thyroid doses among the subjects were 10.2 Gy in Belarus and 5.3 Gy in Russia. Iodine-131 intake was the main pathway for thyroid exposure. Estimated doses from short-lived radioiodines and radiotelluriums ranged up to 0.53 Gy. Reconstructed individual thyroid doses from external exposure ranged up to 0.1 Gy, while those from internal exposure due to ingested cesium did not exceed 0.05 Gy. The uncertainty of the reconstructed individual thyroid doses, characterized by the geometric standard deviation, varies from 1.7 to 4.0 with a median of 2.2.

  2. Cesium in Arctic char lakes - effects of the Chernobyl accident. Radioaktivt cesium i roedingsjoear - effekter av Tjernobylkatastrofen

    Energy Technology Data Exchange (ETDEWEB)

    Hammar, J. (Fiskeriverkets Soetvattenslaboratorium, Drottningholm (Sweden)); Notter, M.; Neumann, G. (Statens Naturvaardesverks Miljoekontrollaboratorium, Drottningholm (Sweden))

    1991-01-01

    Fallout radiocesium from the Chernobyl accident caused extensive contamination in a region of previously well studied alpine lake ecosystems in northern Sweden. Levels of Cs-137 in the barren catchment basins reached 20-50 kBq/m[sup 2] during 1986. The distribution, pathways and major transport mechanisms of radiocesium through the lake ecosystems were studied during 1986-1990. Levels of Cs-137, Cs-134 and K-40 in water, surface sediment, detritus (sediment traps) and different trophic levels of the food chains of Arctic char (Salvelinus alpinus) and brown trout (Salmo trutta) were monitored in a series of lakes forming a matrix of 4 natural lakes and 3 lake reservoirs, with or without the introduced new fish food organism, Mysis relicta. The reservoirs were found to act as sinks for radiocesium with extensive accumulation recorded in water, detritus, sediment, invertebrates and salmonids. Whereas concentrations in water and biota have declined from the extreme peak levels in 1986-1987, the levels in surface sediment increased extensively until fall of 1988. The concentration of Cs-137 in fish populations feeding on benthic invertebrates, i.e. mysids and amphipods, were significantly higher than in planktivorous fish. During the three first winters a significant increase in levels of Cs-137 in winter active Arctic char were recorded, whereas the levels declined during the succeeding summers. The introduced Mysis relicta were found to enhance the transport of Cs-137 from zooplankton and settling particles to Arctic char and brown trout. The results suggest a successive change in transport of radiocesium from water via zooplankton to planktivorous fish during the early summer of 1986 to post-depositional mobilization via benthic organisms to benthic fish in successive years. (213 refs.) (au).

  3. Severe Accidents and New Reactors. Twenty Years of Research; Accidents severos y nuevos reactores. Veinte anos de investigacion

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Jimenez, J.

    2008-07-01

    A review was done on the main activities performed by the Programme for Nuclear Safety of CIEMAT in the field of nuclear reactor safety from 1985 to 2005. It covers the areas of severe accident and source term, advanced and passive reactors, containments analyses and plant applications. It is emphasized CIEMATs participation in national and international projects mainly in those supported by CSN, OECD and the EU. At the same time, experimental and analytical capabilities set up at CIEMAT, as PECA, RECA and GIRS for simulating aerosol pool scrubbing phenomena, hydrogen catalytic recombiner and sprays are been presented, together with an Annex on Generation IV. Two chapters were added, one on the nuclear power reactors in the world and another about the safety systems and principles. (Author)

  4. Radiation monitoring using imaging plate technology: A case study of leaves affected by the Chernobyl nuclear power plant and JCO criticality accidents

    Directory of Open Access Journals (Sweden)

    Kimura Shinzo

    2006-01-01

    Full Text Available This paper describes the use of a photostimulable phosphor screen imaging technique to detect radioactive contamination in the leaves of wormwood (Artemisia vulgaris L and fern (Dryopteris filix-max CL. Schoff plants affected by the Chernobyl nuclear power plant accident. The imaging plate technology is well known for many striking performances in two-dimensional radiation detection. Since imaging plate comprises an integrated detection system, it has been extensively applied to surface contamination distribution studies. In this study, plant samples were collected from high- and low-contaminated areas of Ukraine and Belarus, which were affected due to the Chernobyl accident and exposed to imaging technique. Samples from the highly contaminated areas revealed the highest photo-stimulated luminescence on the imaging plate. Moreover, the radio nuclides detected in the leaves by gamma and beta ray spectroscopy were 137Cs and 90Sr, respectively. Additionally, in order to assess contamination, a comparison was also made with leaves of plants affected during the JCO criticality accident in Japan. Based on the results obtained, the importance of imaging plate technology in environmental radiation monitoring has been suggested.

  5. Major Factors Affecting Incidence of Childhood Thyroid Cancer in Belarus after the Chernobyl Accident: Do Nitrates in Drinking Water Play a Role?

    Science.gov (United States)

    Drozd, Valentina M; Saenko, Vladimir A; Brenner, Alina V; Drozdovitch, Vladimir; Pashkevich, Vasilii I; Kudelsky, Anatoliy V; Demidchik, Yuri E; Branovan, Igor; Shiglik, Nikolay; Rogounovitch, Tatiana I; Yamashita, Shunichi; Biko, Johannes; Reiners, Christoph

    2015-01-01

    One of the major health consequences of the Chernobyl Nuclear Power Plant accident in 1986 was a dramatic increase in incidence of thyroid cancer among those who were aged less than 18 years at the time of the accident. This increase has been directly linked in several analytic epidemiological studies to iodine-131 (131I) thyroid doses received from the accident. However, there remains limited understanding of factors that modify the 131I-related risk. Focusing on post-Chernobyl pediatric thyroid cancer in Belarus, we reviewed evidence of the effects of radiation, thyroid screening, and iodine deficiency on regional differences in incidence rates of thyroid cancer. We also reviewed current evidence on content of nitrate in groundwater and thyroid cancer risk drawing attention to high levels of nitrates in open well water in several contaminated regions of Belarus, i.e. Gomel and Brest, related to the usage of nitrogen fertilizers. In this hypothesis generating study, based on ecological data and biological plausibility, we suggest that nitrate pollution may modify the radiation-related risk of thyroid cancer contributing to regional differences in rates of pediatric thyroid cancer in Belarus. Analytic epidemiological studies designed to evaluate joint effect of nitrate content in groundwater and radiation present a promising avenue of research and may provide useful insights into etiology of thyroid cancer.

  6. Major Factors Affecting Incidence of Childhood Thyroid Cancer in Belarus after the Chernobyl Accident: Do Nitrates in Drinking Water Play a Role?

    Directory of Open Access Journals (Sweden)

    Valentina M Drozd

    Full Text Available One of the major health consequences of the Chernobyl Nuclear Power Plant accident in 1986 was a dramatic increase in incidence of thyroid cancer among those who were aged less than 18 years at the time of the accident. This increase has been directly linked in several analytic epidemiological studies to iodine-131 (131I thyroid doses received from the accident. However, there remains limited understanding of factors that modify the 131I-related risk. Focusing on post-Chernobyl pediatric thyroid cancer in Belarus, we reviewed evidence of the effects of radiation, thyroid screening, and iodine deficiency on regional differences in incidence rates of thyroid cancer. We also reviewed current evidence on content of nitrate in groundwater and thyroid cancer risk drawing attention to high levels of nitrates in open well water in several contaminated regions of Belarus, i.e. Gomel and Brest, related to the usage of nitrogen fertilizers. In this hypothesis generating study, based on ecological data and biological plausibility, we suggest that nitrate pollution may modify the radiation-related risk of thyroid cancer contributing to regional differences in rates of pediatric thyroid cancer in Belarus. Analytic epidemiological studies designed to evaluate joint effect of nitrate content in groundwater and radiation present a promising avenue of research and may provide useful insights into etiology of thyroid cancer.

  7. Pre- and post-Chernobyl accident levels of 129I and 137Cs in the Southern Baltic Sea by brown seaweed Fucus vesiculosus.

    Science.gov (United States)

    Gómez-Guzmán, J M; Holm, E; Enamorado-Báez, S M; Abril, J A; Pinto-Gómez, A R; López-Gutiérrez, J M; García-León, M

    2013-01-01

    (129)I is a very long-lived radionuclide (T(1/2) = 15.7 × 10(6) years) that is present in the environment both because of natural and anthropogenic sources. In this work (129)I concentration and (129)I/(127)I ratio have been determined in seaweed Fucus vesiculosus collected in the Southern Baltic Sea during 1982 and 1986 (post-Chernobyl accident). The resulting data were evaluated in terms of (129)I concentrations, (129)I/(127)I and (129)I/(137)Cs ratios. (129)I concentrations were found to be in the order of (0.82-5.89) × 10(9) atoms g(-1) in 1982 and (1.33-38.83) × 10(9) atoms g(-1) in 1986. The (129)I/(127)I ratios ranged from (22.7-87.8) × 10(-10) for seaweed collected in 1982 and from (26.1-305.5) × 10(-10) for seaweed collected in 1986. Also a linear relationship was established for (127)I concentrations in seawater and salinity in this area, enabling the estimation of concentration factors for (127)I in F. vesiculosus. The high levels of (129)I and (129)I/(127)I in the Kattegat and their gradually decreasing trend to the Baltic Sea indicates that the most important contribution to the (129)I inventory in the Baltic Sea area comes from Sellafield and La Hague reprocessing plants. With respect to Chernobyl accident, (129)I concentrations in samples collected in 1986 were not much higher than those expected in less contaminated samples from 1982. This supports the view that the contribution of the Chernobyl accident to (129)I in the Baltic region was not significant.

  8. Long-term therapy for polymorphic mental disorders in liquidators of the consequences of the accident at the Chernobyl nuclear power plant

    Directory of Open Access Journals (Sweden)

    V. N. Krasnov

    2012-01-01

    Full Text Available The paper gives the results of a long-term comparative therapeutic study of a large cohort of more than 500 liquidators of the consequences of the accident at the Chernobyl nuclear power plant in 1986. The patients were followed up (and periodically treated at hospital 5 years or more, usually 10—15 years. The study confirmed mainly the cerebrovascular nature of disorders following the pattern seen in moderate psychoorganic syndrome. Therapy with cerebroprotective agents having vascular vegetotropic properties could yield certain therapeutic results and, to some extent, preserve social functioning capacity in these patients.

  9. Decontamination tests in the recreational areas affected by the Chernobyl accident: efficiency of decontamination and long-term stability of the effects

    DEFF Research Database (Denmark)

    Ramzaev, V.; Barkovsky, A.; Mishine, A.;

    2013-01-01

    The paper provides a review of the decontamination tests and the follow up monitoring program conducted by the Russian and Danish researchers in two recreational areas in the period 1995–2003. The recreational areas Novie Bobovichi and Muravinka consisted of sets of wooden and brick summer houses...... of the Fukushima accident....... in forest-grassland surroundings. The sites are located on the territory of the Bryansk region (Russia) at a distance of about 180 km north-east of the Chernobyl Nuclear Power Plant. Before intervention began, the inventory of 137Cs in soil was determined at a level of 1000 kBq m-2. The collaborative...

  10. Interception of the Fukushima reactor accident-derived 137Cs, 134Cs and 131I by coniferous forest canopies

    Science.gov (United States)

    Kato, Hiroaki; Onda, Yuichi; Gomi, Takashi

    2012-10-01

    The Fukushima Daiichi nuclear power plant accident resulted in extensive radioactive contamination of the surrounding forests. In this study, we analyzed fallout 137Cs, 134Cs, and 131I in rainwater, throughfall, and stemflow in coniferous forest plantations immediately after the accident. We show selective fractionation of the deposited radionuclides by the forest canopy and contrasting transfer of radiocesium and 131I from the canopy to the forest floor in association with precipitation. More than 60% of the total deposited radiocesium remained in the canopy after 5 month of the initial fallout, while marked penetration of the initially deposited 131I through the canopy was observed. The half-lives of 137Cs absorbed in the cypress and cedar canopies were calculated as 620 days and 890 days, respectively for the period of 0-160 days. The transfer of the deposited radiocesium from the canopy to the forest floor was slow compared with that of the spruce forest affected by fallout from the Chernobyl nuclear reactor accident.

  11. Sodium fast reactor gaps analysis of computer codes and models for accident analysis and reactor safety.

    Energy Technology Data Exchange (ETDEWEB)

    Carbajo, Juan (Oak Ridge National Laboratory, Oak Ridge, TN); Jeong, Hae-Yong (Korea Atomic Energy Research Institute, Daejeon, Korea); Wigeland, Roald (Idaho National Laboratory, Idaho Falls, ID); Corradini, Michael (University of Wisconsin, Madison, WI); Schmidt, Rodney Cannon; Thomas, Justin (Argonne National Laboratory, Argonne, IL); Wei, Tom (Argonne National Laboratory, Argonne, IL); Sofu, Tanju (Argonne National Laboratory, Argonne, IL); Ludewig, Hans (Brookhaven National Laboratory, Upton, NY); Tobita, Yoshiharu (Japan Atomic Energy Agency, Ibaraki-ken, Japan); Ohshima, Hiroyuki (Japan Atomic Energy Agency, Ibaraki-ken, Japan); Serre, Frederic (Centre d' %C3%94etudes nucl%C3%94eaires de Cadarache %3CU%2B2013%3E CEA, France)

    2011-06-01

    This report summarizes the results of an expert-opinion elicitation activity designed to qualitatively assess the status and capabilities of currently available computer codes and models for accident analysis and reactor safety calculations of advanced sodium fast reactors, and identify important gaps. The twelve-member panel consisted of representatives from five U.S. National Laboratories (SNL, ANL, INL, ORNL, and BNL), the University of Wisconsin, the KAERI, the JAEA, and the CEA. The major portion of this elicitation activity occurred during a two-day meeting held on Aug. 10-11, 2010 at Argonne National Laboratory. There were two primary objectives of this work: (1) Identify computer codes currently available for SFR accident analysis and reactor safety calculations; and (2) Assess the status and capability of current US computer codes to adequately model the required accident scenarios and associated phenomena, and identify important gaps. During the review, panel members identified over 60 computer codes that are currently available in the international community to perform different aspects of SFR safety analysis for various event scenarios and accident categories. A brief description of each of these codes together with references (when available) is provided. An adaptation of the Predictive Capability Maturity Model (PCMM) for computational modeling and simulation is described for use in this work. The panel's assessment of the available US codes is presented in the form of nine tables, organized into groups of three for each of three risk categories considered: anticipated operational occurrences (AOOs), design basis accidents (DBA), and beyond design basis accidents (BDBA). A set of summary conclusions are drawn from the results obtained. At the highest level, the panel judged that current US code capabilities are adequate for licensing given reasonable margins, but expressed concern that US code development activities had stagnated and that the

  12. The Chernobyl accident 20 years on: an assessment of the health consequences and the international response O acidente de Chernobyl 20 anos depois: avaliação das conseqüências e resposta internacional

    Directory of Open Access Journals (Sweden)

    Keith Baverstock

    2007-06-01

    Full Text Available Twenty years after the Chernobyl accident the WHO and the International Atomic Energy Authority issued a reassuring statement about the consequences. Our objectives in this study were to evaluate the health impact of the Chernobyl accident, assess the international response to the accident, and consider how to improve responses to future accidents. So far, radiation to the thyroid from radioisotopes of iodine has caused several thousand cases of thyroid cancer but very few deaths; exposed children were most susceptible. The focus on thyroid cancer has diverted attention from possible nonthyroid effects. The international response to the accident was inadequate and uncoordinated, and has been unjustifiably reassuring. Accurate assessment in future health effects is not currently possible in the light of dose uncertainties, current debates over radiation actions, and the lessons from the late consequences of atomic bomb exposure. Because of the uncertainties from and the consequences of the accident, it is essential that investigations of its effects should be broadened and supported for the long term. The United Nations should initiate an independent review of the actions and assignments of the agencies concerned, with recommendations for dealing with future international-scale accidents. These should involve independent scientists and ensure cooperation rather than rivalry.Vinte anos após o acidente de Chernobyl ocorrido em 1986, a OMS e a Autoridade Internacional sobre Energia Atômica lançaram um relatório sobre as conseqüências desse desastre. Nosso objetivo neste estudo é avaliar o impacto de tal acidente sobre a saúde e a reação internacional sobre o ocorrido, além de considerar se é possível melhorar as respostas em futuros desastres. Observamos que a radiação sobre a tireóide, proveniente de radioisótopos de iodo, causou milhares de casos de câncer, mas poucas mortes; as crianças expostas foram as mais suscetíveis. O

  13. The Chernobyl Catastrophe. Consequences on Human Health

    Energy Technology Data Exchange (ETDEWEB)

    Yablokov, A.; Labunska, I.; Blokov, I. (eds.)

    2006-04-15

    of estimates of excess mortality resulting from the Chernobyl accident spans an extremely wide range depending upon precisely what is taken into account. The most recent epidemiological evidence, published under the auspices of the Russian Academy of Sciences, suggests that the scale of the problems could be very much greater than predicted by studies published to date. For example, the 2005 IAEA report predicted that 4000 additional deaths would result from the Chernobyl accident. The most recently published figures indicate that in Belarus, Russia and the Ukraine alone the accident resulted in an estimated 200,000 additional deaths between 1990 and 2004. Overall, the available data reveal a considerable range in estimated excess mortalities resulting from the Chernobyl accident, serving to underline the huge uncertainties attached to knowledge of the full impacts of the Chernobyl accident. This report includes some data, which have not been published before in the international arena. In combination with the extensive body of literature which has been published to date, these data indicate that 'official' figures (e.g. the IAEA 2005 evaluation) for morbidity (incidence of disease) and death arising as a direct result of the radioactive contamination released from Chernobyl may grossly underestimate both the local and international impact of the incident. Four population groups appear to have experienced the most severe health effects: (1) accident clean-up workers, or 'liquidators', including civilian and the military personnel drafted to carry out clean-up activities and construct the protective cover for the reactor; (2) evacuees from dangerously contaminated territories inside the 30-km zone around the power plant; (3) residents of the less (but still dangerously) contaminated territories; and (4) children born into the families from all of the above three groups.

  14. Specific complex of non-radiation risk factors for socially significant pathologies could affect the liquidators of Chernobyl nuclear power plant accident

    Directory of Open Access Journals (Sweden)

    Koterov A.N.

    2014-12-01

    Full Text Available The review considers the complex of non-radiation factors that could affect the liquidators of the Chernobyl accident: the demographic, social and professional group heterogeneity to warrant differentiation of risk, the effects of heavy metals, 'hot particles', chemicals, psychogenic stress, social dislocation in the post-perestroika period, alcohol abuse, smoking, and the effect of screening. All these factors tend to have a significant intensity, unlike the radiation exposure for the majority of subjects. It is concluded that the increased frequency and severity of some large socially significant pathologies in contingent liquidators may be due to a unique set of predominantly non-radiation factors associated, however, with a particular radiation accident.

  15. Structure of the thyroid pathology in the radiation exposed areas of Leningrad region: late consequences of Chernobyl accident after 20 years

    Energy Technology Data Exchange (ETDEWEB)

    Semenov, A.; Uspenskaya, A.; Bychenkova, E.; Chinchuk, I.; Novokshonov, K.; Chernikov, R.; Sleptsov, I.; Bubnov, A.; Fedotov, Y.; Makarin, V.; Karelina, Y. [Endocrinology, NWRMC FHSDA, ST-Petersburg (Russian Federation)

    2012-07-01

    After the Chernobyl accident large areas of the USSR were contaminated with fallout, it has been proved that I{sup 131} caused higher incidence of papillary thyroid cancer in children and adolescents. Further observation for over 20 years showed retention of high annual prevalence of this pathology among the population. The aim of this study is to evaluate the ultimate result of the influence of I{sup 131} on the thyroid gland. The study included 454 women living in localities affected by the Chernobyl accident in April-May 1986 (case) and 909 women living in fallout-free localities (ICCIDD method). The incidence of malignant thyroid tumors among the inhabitants of the contaminated territories is higher than in the control area. This phenomenon can not be unambiguously attributed to radiation induced cancers, but requires further investigation, perhaps by the method of carrying out continuous and all-round prophylactic medical examination. High incidence of autoimmune changes can be considered to have been caused by the action of I{sup 131} and prophylactic supplement with stable iodine

  16. Spatial variability of the dose rate from (137)Cs fallout in settlements in Russia and Belarus more than two decades after the Chernobyl accident.

    Science.gov (United States)

    Bernhardsson, C; Rääf, C L; Mattsson, S

    2015-11-01

    Radionuclides from the 1986 Chernobyl accident were released and dispersed during a limited period of time, but under widely varying weather conditions. As a result, there was a high geographical variation in the deposited radioactive fallout per unit area over Europe, depending on the released composition of fission products and the weather during the 10 days of releases. If the plume from Chernobyl coincided with rain, then the radionuclides were unevenly distributed on the ground. However, large variations in the initial fallout also occurred locally or even on a meter scale. Over the ensuing years the initial deposition may have been altered further by different weathering processes or human activities such as agriculture, gardening, and decontamination measures. Using measurements taken more than two decades after the accident, we report on the inhomogeneous distribution of the ground deposition of the fission product (137)Cs and its influence on the dose rate 1 m above ground, on both large and small scales (10ths of km(2) - 1 m(2)), in the Gomel-Bryansk area close to the border between Belarus and Russia. The dose rate from the deposition was observed to vary by one order of magnitude depending on the size of the area considered, whether human processes were applied to the surface or not, and on location specific properties (e.g. radionuclide migration in soil).

  17. SCIENTIFIC SUPPORT OF THE MEDICAL SECTION OF THE STATE PROGRAM OF THE BELARUS REPUBLIC FOR THE OVERCOMING OF THE CHERNOBYL ACCIDENT CONSEQUENCES

    Directory of Open Access Journals (Sweden)

    A. V. Rozhko

    2012-01-01

    Full Text Available A twenty-five year health follow-up of the affected population has shown that a properly structured State strategy on overcoming the consequences of disaster allow to maintain stable levels of morbidity and mortality. An important achievement in the system of medical help to the affected population is the organization of dynamic follow-up, as well as creating State Register of people exposed to radiation as a result of the Chernobyl accident as a tool for solving scientific and practical problems. The results of scientific researches obtained in the SO “The Republican Research Centre for Radiation Medicine and Human Ecology” were the basis for one of the Council of Ministers Decree and two Decrees of the Ministry of Health. Significant changes have been made in the order of assigning the causation connection of disease (disability and the accident at the Chernobyl nuclear power plant and objective criteria for the formation of high radiation risk groups.In a whole, the rate of oncological morbidity in the affected population remains at the average republican level, but for certain categories of the affected population, referred to groups of enhanced radiation risk, there has been detected the presence of excess morbidity of some forms of malignant neoplasms.

  18. Reconstructing the Chernobyl Nuclear Power Plant (CNPP) accident 30 years after. A unique database of air concentration and deposition measurements over Europe.

    Science.gov (United States)

    Evangeliou, Nikolaos; Hamburger, Thomas; Talerko, Nikolai; Zibtsev, Sergey; Bondar, Yuri; Stohl, Andreas; Balkanski, Yves; Mousseau, Timothy A; Møller, Anders P

    2016-09-01

    30 years after the Chernobyl Nuclear Power Plant (CNPP) accident, its radioactive releases still remain of great interest mainly due to the long half-lives of many radionuclides emitted. Observations from the terrestrial environment, which hosts radionuclides for many years after initial deposition, are important for health and environmental assessments. Furthermore, such measurements are the basis for validation of atmospheric transport models and can be used for constraining the still not accurately known source terms. However, although the "Atlas of cesium deposition on Europe after the Chernobyl accident" (hereafter referred to as "Atlas") has been published since 1998, less than 1% of the direct observations of (137)Cs deposition has been made publicly available. The remaining ones are neither accessible nor traceable to specific data providers and a large fraction of these data might have been lost entirely. The present paper is an effort to rescue some of the data collected over the years following the CNPP accident and make them publicly available. The database includes surface air activity concentrations and deposition observations for (131)I, (134)Cs and (137)Cs measured and provided by Former Soviet Union authorities the years that followed the accident. Using the same interpolation tool as the official authorities, we have reconstructed a deposition map of (137)Cs based on about 3% of the data used to create the Atlas map. The reconstructed deposition map is very similar to the official one, but it has the advantage that it is based exclusively on documented data sources, which are all made available within this publication. In contrast to the official map, our deposition map is therefore reproducible and all underlying data can be used also for other purposes. The efficacy of the database was proved using simulated activity concentrations and deposition of (137)Cs from a Langrangian and a Euleurian transport model.

  19. Exposure from the Chernobyl accident had adverse effects on erythrocytes, leukocytes, and, platelets in children in the Narodichesky region, Ukraine: A 6-year follow-up study

    Directory of Open Access Journals (Sweden)

    Svendsen Erik

    2008-05-01

    Full Text Available Abstract Background After the Chernobyl nuclear accident on April 26, 1986, all children in the contaminated territory of the Narodichesky region, Zhitomir Oblast, Ukraine, were obliged to participate in a yearly medical examination. We present the results from these examinations for the years 1993 to 1998. Since the hematopoietic system is an important target, we investigated the association between residential soil density of 137Caesium (137Cs and hemoglobin concentration, and erythrocyte, platelet, and leukocyte counts in 1,251 children, using 4,989 repeated measurements taken from 1993 to 1998. Methods Soil contamination measurements from 38 settlements were used as exposures. Blood counts were conducted using the same auto-analyzer in all investigations for all years. We used linear mixed models to compensate for the repeated measurements of each child over the six year period. We estimated the adjusted means for all markers, controlling for potential confounders. Results Data show a statistically significant reduction in red and white blood cell counts, platelet counts and hemoglobin with increasing residential 137Cs soil contamination. Over the six-year observation period, hematologic markers did improve. In children with the higher exposure who were born before the accident, this improvement was more pronounced for platelet counts, and less for red blood cells and hemoglobin. There was no exposure×time interaction for white blood cell counts and not in 702 children who were born after the accident. The initial exposure gradient persisted in this sub-sample of children. Conclusion The study is the first longitudinal analysis from a large cohort of children after the Chernobyl accident. The findings suggest persistent adverse hematological effects associated with residential 137Cs exposure.

  20. Medical lessons learned from chernobyl relative to nuclear detonations and failed nuclear reactors.

    Science.gov (United States)

    Dallas, Cham E

    2012-12-01

    The Chernobyl disaster in 1986 involved the largest airborne release of radioactivity in history, more than 100 times as much radioactivity as the Hiroshima and Nagasaki atomic bombs together. The resulting emergency response, administrative blunders, and subsequent patient outcomes from this large-scale radiological disaster provide a wealth of information and valuable lessons for those who may find themselves having to deal with the staggering consequences of nuclear war. Research findings, administrative strategies (successful and otherwise), and resulting clinical procedures from the Chernobyl experience are reviewed to determine a current utility in addressing the appropriate protocols for a medical response to nuclear war. As various myths are still widely associated with radiation exposure, attention is given to the realities of a mass casualty medical response as it would occur with a nuclear detonation.

  1. High-resolution historical records from Pettaquamscutt River basin sediments: 1. 210Pb and varve chronologies validate record of 137Cs released by the Chernobyl accident

    Science.gov (United States)

    Lima, Ana Lúcia; Hubeny, J. Bradford; Reddy, Christopher M.; King, John W.; Hughen, Konrad A.; Eglinton, Timothy I.

    2005-04-01

    Cesium-137 derived from the explosion of the Chernobyl reactor in 1986 was preserved in anoxic sediments from a coastal environment in southern Rhode Island. Although the radioactive plume was detected in surface air samples at several locations in the United States, this is the first known record of a Chernobyl 137Cs peak in sediments from North America. The inventory of Chernobyl 137Cs that was preserved in the Pettaquamscutt River is small compared to European counterparts and should only be detectable for the next 15-20 yr. However, the presence of two 137Cs peaks (1963 and 1987) identifies a well-dated segment of the sediment column that could be exploited in understanding the decomposition and preservation of terrestrial and aquatic organic matter. Different methods for calculating the 210Pb chronology were also evaluated in this study and checked against independent varve counting. The end result is a detailed chronology of a site well suited for reconstruction of historical records of environmental change.

  2. 77 FR 61446 - Proposed Revision Probabilistic Risk Assessment and Severe Accident Evaluation for New Reactors

    Science.gov (United States)

    2012-10-09

    ... COMMISSION Proposed Revision Probabilistic Risk Assessment and Severe Accident Evaluation for New Reactors... comment on NUREG-0800, ``Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power..., ``Probabilistic Risk Assessment and Severe Accident Evaluation for New Reactors.'' DATES: Submit comments...

  3. 77 FR 66649 - Proposed Revision to Probabilistic Risk Assessment and Severe Accident Evaluation for New Reactors

    Science.gov (United States)

    2012-11-06

    ... COMMISSION Proposed Revision to Probabilistic Risk Assessment and Severe Accident Evaluation for New Reactors... the Commission), issued a NUREG-0800, ``Standard Review Plan for the Review of Safety Analysis Reports...), Section 19.0 ``Probabilistic Risk Assessment and Severe Accident Evaluation for New Reactors.'' The NRC...

  4. ASSESSMENT OF THE RADIONUCLIDE COMPOSITION OF "HOT PARTICLES" SAMPLED IN THE CHERNOBYL NUCLEAR POWER PLANT FOURTH REACTOR UNIT

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.; Marra, J.

    2011-10-01

    Fuel-containing materials sampled from within the Chernobyl Nuclear Power Plant (ChNPP) 4th Reactor Unit Confinement Shelter were spectroscopically studied for gamma and alpha content. Isotopic ratios for cesium, europium, plutonium, americium, and curium were identified and the fuel burnup in these samples was determined. A systematic deviation in the burnup values based on the cesium isotopes, in comparison with other radionuclides, was observed. The conducted studies were the first ever performed to demonstrate the presence of significant quantities of {sup 242}Cm and {sup 243}Cm. It was determined that there was a systematic underestimation of activities of transuranic radionuclides in fuel samples from inside of the ChNPP Confinement Shelter, starting from {sup 241}Am (and going higher), in comparison with the theoretical calculations.

  5. [The morphological status of the maxillodental system in children living in an area contaminated by radionuclides as a result of the accident at the Chernobyl Atomic Electric Power Station].

    Science.gov (United States)

    Sevbitov, A V; Persin, L S; Slabkobskaia, A B; Pankratova, N V

    1999-01-01

    The present study has been done in the framework of federal programme "Children of Chernobyl" with the aim to determine spread and structure of dental jaw abnormalities in children born and living in the radiation polluted regions after Chernobyl accident in 1986. 183 children have been examined in Donskoi town of Tula Province with the polluted soil by Cs-137 up to 5 Ci/km. All the examined children were divided into 2 groups: group 1--born in 1980-1986 and group 2--born in 1987-1994. It was determined that 76.5% of children have dental jaw system abnormalities. The most spread ones were occlusion abnormalities in combination with teeth abnormalities (28.9% cases) while the state of dental jaw system corresponding to the age standard was 2 times rarer in children born after the Chernobyl accident.

  6. Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendices VII, VIII, IX, and X. [PWR and BWR

    Energy Technology Data Exchange (ETDEWEB)

    1975-10-01

    Information is presented concerning the release of radioactivity in reactor accidents; physical processes in reactor meltdown accidents; safety design rationale for nuclear power plants; and design adequacy.

  7. Analysis of the results of environmental monitoring in Spain after the Chernobyl and Fukushima accidents; Analisis de los resultados de la vigilancia radiologica ambiental en Espana tras los accidentes de Chernobil y Fukusima

    Energy Technology Data Exchange (ETDEWEB)

    Luque Heredia, S.; Salas Collantes, R.; Rey del castillo, C.; Marugar tovar, I.; Sterling carmona, A.; Ramos Salvador, L.; Lorente Lorente, P.

    2013-07-01

    As a result of accidents at Chernobyl and Fukushima nuclear power plants, CSN launched special surveillance devices to monitor radioactive contamination through the values provided by the various networks and environmental monitoring programs. The aim of this study is to compare and analyze the results corresponding to the exposure pathways and matrices in which contamination is detected. (Author)

  8. Reactor vessel water level estimation during severe accidents using cascaded fuzzy neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Yeong; Yoo, Kwae Hwan; Choi, Geon Pil; Back, Ju Hyun; Na, Man Gyun [Dept. of Nuclear Engineering, Chosun University, Gwangju (Korea, Republic of)

    2016-06-15

    Global concern and interest in the safety of nuclear power plants have increased considerably since the Fukushima accident. In the event of a severe accident, the reactor vessel water level cannot be measured. The reactor vessel water level has a direct impact on confirming the safety of reactor core cooling. However, in the event of a severe accident, it may be possible to estimate the reactor vessel water level by employing other information. The cascaded fuzzy neural network (CFNN) model can be used to estimate the reactor vessel water level through the process of repeatedly adding fuzzy neural networks. The developed CFNN model was found to be sufficiently accurate for estimating the reactor vessel water level when the sensor performance had deteriorated. Therefore, the developed CFNN model can help provide effective information to operators in the event of a severe accident.

  9. Chernobyl radionuclide distribution and migration.

    Science.gov (United States)

    Izrael, Yury A

    2007-11-01

    The accident at Unit No. 4 of the Chernobyl Nuclear Power Plant on 26 April 1986 presented severe challenges in radiation protection. Early activity measurements defined the contaminated areas in order to determine what persons should be evacuated on the basis of the exposure limit at that time of 100 mSv (10 rem) for accidents. The immediate definition of these areas was accomplished with specially equipped aircraft capable of measuring external gamma-exposure rate and radionuclide spectra. Over time, maps of 137Cs contamination (the most important long-lived radionuclide) have become more and more sophisticated and have been used for further determinations of the control of the consequences of the accident. About 70% of the total release of 137Cs was deposited in Belarus, the Russian Federation, and Ukraine; but there was also widespread deposition throughout the countries of Western Europe. Two atlases of contamination throughout Europe were prepared, and the Russian atlas included data on other radionuclides and on external gamma-exposure rates. The radiocesiums behaved as volatile radionuclides because of the volatility of cesium. In contrast to the typical pattern after nuclear weapons tests, 90Sr behaved only as a refractory element, as its volatile precursors krypton and rubidium had already decayed within the reactor. Nearly all of the refractory elements (strontium, plutonium, etc.) released by the accident were confined to the 30-km zone around the reactor. A proposal is made to develop a more complete atlas of 137Cs deposition from the accident that would include the entire Northern Hemisphere. Water was not an important vector of exposure to human beings following the accident.

  10. Global and local cancer risks after the Fukushima Nuclear Power Plant accident as seen from Chernobyl: a modeling study for radiocaesium ((134)Cs &(137)Cs).

    Science.gov (United States)

    Evangeliou, Nikolaos; Balkanski, Yves; Cozic, Anne; Møller, Anders Pape

    2014-03-01

    The accident at the Fukushima Daiichi Nuclear Power Plant (NPP) in Japan resulted in the release of a large number of fission products that were transported worldwide. We study the effects of two of the most dangerous radionuclides emitted, (137)Cs (half-life: 30.2years) and (134)Cs (half-life: 2.06years), which were transported across the world constituting the global fallout (together with iodine isotopes and noble gasses) after nuclear releases. The main purpose is to provide preliminary cancer risk estimates after the Fukushima NPP accident, in terms of excess lifetime incident and death risks, prior to epidemiology, and compare them with those occurred after the Chernobyl accident. Moreover, cancer risks are presented for the local population in the form of high-resolution risk maps for 3 population classes and for both sexes. The atmospheric transport model LMDZORINCA was used to simulate the global dispersion of radiocaesium after the accident. Air and ground activity concentrations have been incorporated with monitoring data as input to the LNT-model (Linear Non-Threshold) frequently used in risk assessments of all solid cancers. Cancer risks were estimated to be small for the global population in regions outside Japan. Women are more sensitive to radiation than men, although the largest risks were recorded for infants; the risk is not depended on the sex at the age-at-exposure. Radiation risks from Fukushima were more enhanced near the plant, while the evacuation measures were crucial for its reduction. According to our estimations, 730-1700 excess cancer incidents are expected of which around 65% may be fatal, which are very close to what has been already published (see references therein). Finally, we applied the same calculations using the DDREF (Dose and Dose Rate Effectiveness Factor), which is recommended by the ICRP, UNSCEAR and EPA as an alternative reduction factor instead of using a threshold value (which is still unknown). Excess lifetime cancer

  11. Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences. [PWR and BWR

    Energy Technology Data Exchange (ETDEWEB)

    1975-10-01

    Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model.

  12. Total cancer incidence in relation to 137Cs fallout in the most contaminated counties in Sweden after the Chernobyl nuclear power plant accident: a register-based study

    Science.gov (United States)

    Alinaghizadeh, Hassan; Wålinder, Robert; Vingård, Eva; Tondel, Martin

    2016-01-01

    Objectives To determine the total cancer incidence in relation to a 5-year exposure to caesium-137 (137Cs) from the 1986 Chernobyl nuclear power plant accident. Methods A closed cohort was defined as all individuals living in the three most contaminated counties in mid-Sweden in 1986. Fallout of 137Cs was retrieved as a digital map from the Geological Survey of Sweden, demographic data from Statistics Sweden, and cancer diagnosis from the National Board of Health and Welfare. Individuals were assigned an annual 137Cs exposure based on their place of residence (1986–1990), from which 5-year cumulative 137Cs exposures were calculated, accounting for the physical decay of 137Cs and changing residencies. HRs were adjusted for age, sex, rural/non-rural residence and pre-Chernobyl total cancer incidence. Results The 734 537 people identified were categorised by exposure: the first quartile was low exposure (0.0–45.4 kBq/m2), the second and third quartiles were intermediate exposure (45.41–118.8 kBq/m2), and the fourth quartile was the highest exposure (118.81–564.71 kBq/m2). Between 1991 and 2010, 82 495 cancer cases were registered in the 3 counties. Adjusted HRs (95% CI) were 1.03 (1.01 to 1.05) for intermediate exposure and 1.05 (1.03 to 1.07) for the highest exposure compared to the reference exposure. Conclusions We found a small overall exposure–response pattern of the total cancer incidence related to 137Cs after adjustment for age, sex, rural residence and pre-Chernobyl cancer incidence. PMID:27998898

  13. LIGHT WATER REACTOR ACCIDENT TOLERANT FUELS IRRADIATION TESTING

    Energy Technology Data Exchange (ETDEWEB)

    Carmack, William Jonathan [Idaho National Laboratory; Barrett, Kristine Eloise [Idaho National Laboratory; Chichester, Heather Jean MacLean [Idaho National Laboratory

    2015-09-01

    The purpose of Accident Tolerant Fuels (ATF) experiments is to test novel fuel and cladding concepts designed to replace the current zirconium alloy uranium dioxide (UO2) fuel system. The objective of this Research and Development (R&D) is to develop novel ATF concepts that will be able to withstand loss of active cooling in the reactor core for a considerably longer time period than the current fuel system while maintaining or improving the fuel performance during normal operations, operational transients, design basis, and beyond design basis events. It was necessary to design, analyze, and fabricate drop-in capsules to meet the requirements for testing under prototypic LWR temperatures in Idaho National Laboratory's Advanced Test Reactor (ATR). Three industry led teams and one DOE team from Oak Ridge National Laboratory provided fuel rodlet samples for their new concepts for ATR insertion in 2015. As-built projected temperature calculations were performed on the ATF capsules using the BISON fuel performance code. BISON is an application of INL’s Multi-physics Object Oriented Simulation Environment (MOOSE), which is a massively parallel finite element based framework used to solve systems of fully coupled nonlinear partial differential equations. Both 2D and 3D models were set up to examine cladding and fuel performance.

  14. DYNAMICS OF THE RADIOACTIVE POLLUTION IN THE SURFACE LAYER OF SOILS IN BULGARIA TWENTY YEARS AFTER THE CHERNOBYL NUCLEAR POWER PLANT ACCIDENT

    Directory of Open Access Journals (Sweden)

    I YORDANOVA

    2008-05-01

    Full Text Available The twenty years period past after the contamination with radionuclides in 1986, as a result of the accident in the Chernobyl’s NPP, allowed the accumulation of rich data base for the radiation status of the soils in Bulgaria. Objective of many years studies were virgin soils from high mountain areas, hilly and flat (the region of Kozlodouy NPP and the Danube river valley. Ceasium-137 and strontium-90 were the main men-made radionuclides detected in the examined Bulgarian soils, few years after the accident. The content of ceasium-137 and strontium-90 in the soils from high mountain areas (Rodopa and Rila mountains is several times higher then that in the soils from Northern Bulgaria and Sofia field. High non-homogeneity in the pollution within small areas (scores of square meters even was determined. No significant horizontal redistribution was observed for the period after 1986. The tendency of changes in the radioactive status of the soils in Bulgaria after the accident at the Chernobyl Nuclear Power Plant is not due to trans-border transfer of radioactive materials or to any breakdown at the Kosloduy Nuclear Power Plant.

  15. PARAMETERS OF THE DIETARY PATTERN AND BEHAVIOR OF THE BRYANSK REGION INHABITANTS IN MAY 1986, INFLUENCING THE EVALUATION OF THE DOSE RECEIVED DUE TO THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. A. Zvonova

    2011-01-01

    Full Text Available Results of the poll on the lifestyle and nutrition of the population of the most contaminated areas of the Bryansk and Tula regions during the initial period after the accident at the Chernobyl nuclear power plant are presented in the article. The poll was held at the beginning of 1987. Mean values of numeric factors were derived form the results of processing of questionnaires received from 8500 persons, namely: value of milk daily consumption depending on the age and place of residence, the date of the dairy cattle grazing starting, time of milk consumption termination in May 1986, time spent by the person outdoors and in the dwelling, data on the leaving of the contaminated territory. Obtained information is used for the clarification of models for the internal and external exposure dose calculation and for personalization of the dose estimations for the individual inhabitants.

  16. The Chernobyl accident as an example of how environmental burden may lead to persistent mental stress. Final report. Laengerfristige psychische Folgen von Umweltbelastungen: Das Beispiel Tschernobyl. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Legewie, H.; Boehm, A.; Boehnke, K.; Faas, A.; Gross, B.; Jaeggi, E.

    1990-01-01

    It was the aim of this qualitative analysis to give an account, as detailed and complete as possible, of time-dependent mental reactions to ecological afflictions through the Chernobyl accident as well as to describe reaction and compensation patterns typical for such challenges and to develop preliminary theories to explain the phenomena observed. These efforts make a contribution to basic research in that they pave the way to innovative methods and fields of knowledge that may be of equal relevance to environmental psychology, clinical psychology, social psychology and socioscientific technology. They make a contribution to field research in that the findings revealed elucidate generally held views about the toll of technocracy and environmental destruction. The results appear to be just as relevant to health and environmental counselling, environmental education and environment-oriented editorial work as they are to political decisions concerning future technologies. (orig.).

  17. A model for the release, dispersion and environmental impact of a postulated reactor accident from a submerged commercial nuclear power plant

    Science.gov (United States)

    Bertch, Timothy Creston

    1998-12-01

    Nuclear power plants are inherently suitable for submerged applications and could provide power to the shore power grid or support future underwater applications. The technology exists today and the construction of a submerged commercial nuclear power plant may become desirable. A submerged reactor is safer to humans because the infinite supply of water for heat removal, particulate retention in the water column, sedimentation to the ocean floor and inherent shielding of the aquatic environment would significantly mitigate the effects of a reactor accident. A better understanding of reactor operation in this new environment is required to quantify the radioecological impact and to determine the suitability of this concept. The impact of release to the environment from a severe reactor accident is a new aspect of the field of marine radioecology. Current efforts have been centered on radioecological impacts of nuclear waste disposal, nuclear weapons testing fallout and shore nuclear plant discharges. This dissertation examines the environmental impact of a severe reactor accident in a submerged commercial nuclear power plant, modeling a postulated site on the Atlantic continental shelf adjacent to the United States. This effort models the effects of geography, decay, particle transport/dispersion, bioaccumulation and elimination with associated dose commitment. The use of a source term equivalent to the release from Chernobyl allows comparison between the impacts of that accident and the postulated submerged commercial reactor plant accident. All input parameters are evaluated using sensitivity analysis. The effect of the release on marine biota is determined. Study of the pathways to humans from gaseous radionuclides, consumption of contaminated marine biota and direct exposure as contaminated water reaches the shoreline is conducted. The model developed by this effort predicts a significant mitigation of the radioecological impact of the reactor accident release

  18. Practical improvement of the radiological quality of milk produced by peasant farmers in the territories of Belarus contaminated by the Chernobyl accident. The ETHOS project.

    Science.gov (United States)

    Lepicard, S; Dubreuil, G H

    2001-01-01

    The Chernobyl post-accident situation has highlighted how the sudden emergence of persistent radioactive contamination in the environment is severely affecting the quality of life of the inhabitants in the concerned territories. The management of this situation is complex, mainly conditioned by the ability of the inhabitants themselves to be directly involved in the process of improving their living conditions. In this process, quality of life cannot be restricted solely to the dimension of radiological risk, but needs to encompass the diverse aspects of daily living, including the social, psychological, economic, political and ethical aspects. This paper presents the experience of the involvement of a group of peasant farmers from a village in the Republic of Belarus, in the process of improving the radiological quality of privately produced milk. This experience took place in the context of the ETHOS project, funded by the radiation protection research programme of the European Commission. The principal objective was to implement a complementary approach to the rehabilitation strategies adopted so far in the contaminated territories of the Republic of Belarus. This paper retraces the process of involvement of the inhabitants in a working group. It describes the characterisation of the situation by local actors, the opening of new possible actions to improve the radiological quality of milk at the individual level and the positive consequences at the scale of the village. The ETHOS project also illustrates how the scientific knowledge accumulated over many years since the Chernobyl accident in the field of radiation protection and radioecology can enter into local practices in the form of practical tools, which can be used by the population to produce significant improvements in the radiological situation.

  19. Light water reactor safety

    CERN Document Server

    Pershagen, B

    2013-01-01

    This book describes the principles and practices of reactor safety as applied to the design, regulation and operation of light water reactors, combining a historical approach with an up-to-date account of the safety, technology and operating experience of both pressurized water reactors and boiling water reactors. The introductory chapters set out the basic facts upon which the safety of light water reactors depend. The central section is devoted to the methods and results of safety analysis. The accidents at Three Mile Island and Chernobyl are reviewed and their implications for light wate

  20. Chernobyl and after

    Energy Technology Data Exchange (ETDEWEB)

    Daglish, J.; Gittus, J.

    1986-10-01

    The paper contains two reports on the Chernobyl post-accident review meeting. The first is a factual account of the meeting, the topics discussed include: the accident, preventative action, outcome of the accident, and future interactions with the Russians on nuclear power issues. This report also describes two Accident Conventions, drawn up at the time of the meeting, which cover notification, information, and commitment of assistance in the event of a nuclear accident. The second report is by a member of the International Atomic Energy Agency, who reviews the accident, health effects, human factors, man-machine interference, positive void coefficient, and handling of the accident by the Soviet Authorities. (U.K.).

  1. Empirical Risk Analysis of Severe Reactor Accidents in Nuclear Power Plants after Fukushima

    Directory of Open Access Journals (Sweden)

    Jan Christian Kaiser

    2012-01-01

    Full Text Available Many countries are reexamining the risks connected with nuclear power generation after the Fukushima accidents. To provide updated information for the corresponding discussion a simple empirical approach is applied for risk quantification of severe reactor accidents with International Nuclear and Radiological Event Scale (INES level ≥5. The analysis is based on worldwide data of commercial nuclear facilities. An empirical hazard of 21 (95% confidence intervals (CI 4; 62 severe accidents among the world’s reactors in 100,000 years of operation has been estimated. This result is compatible with the frequency estimate of a probabilistic safety assessment for a typical pressurised power reactor in Germany. It is used in scenario calculations concerning the development in numbers of reactors in the next twenty years. For the base scenario with constant reactor numbers the time to the next accident among the world's 441 reactors, which were connected to the grid in 2010, is estimated to 11 (95% CI 3.7; 52 years. In two other scenarios a moderate increase or decrease in reactor numbers have negligible influence on the results. The time to the next accident can be extended well above the lifetime of reactors by retiring a sizeable number of less secure ones and by safety improvements for the rest.

  2. Evaluation of thyroid antibodies and benign disease prevalence among young adults exposed to 131I more than 25 years after the accident at the Chernobyl Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    Yuko Kimura

    2016-03-01

    Full Text Available Background. The Chernobyl Nuclear Power Plant (CNPP accident exposed a large number of inhabitants to internal 131I radiation. The associations between internal 131I exposure and thyroid autoimmunity and benign thyroid diseases remain controversial in the population living in the contaminated area around the CNNP. In this study, we evaluate the association of 131I with benign thyroid diseases. Methods. We compared the prevalence of Anti-Thyroid Autoantibodies (ATAs, thyroid function, and prevalence of thyroid ultrasound finding outcomes in 300 residents of the contaminated area of Ukraine who were 0–5 years of age at the time of the CNPP accident (group 1 and 300 sex-matched residents who were born after the accident (group 2. Results. We did not find any differences of the prevalence of Antithyroglobulin Antibodies (TGAb positive, Antithyroid Peroxidase Antibodies (TPOAb positive, and TGAb and/or TPOAb positive between the study groups. (11.7% vs 10.3%; p = 0.602, 17.3% vs 13.0%; p = 0.136, 21.0% vs 17.3%; p = 0.254, respectively; after adjusting for age and sex, the prevalence was not associated with the 131I exposure status in the study groups. The prevalence of subclinical and overt hypothyroidism cases was not significantly different (p = 0.093 and p = 0.320 in the two groups, nor was the prevalence of goiter (p = 0.482. On the other hand, the prevalence of nodules was significantly higher in group 1 (p = 0.003, though not significantly so after adjustment for age and sex. Discussion. Working 26–27 years after the CNNP accident, we found no increased prevalence of ATAs or benign thyroid diseases in young adults exposed to 131I fallout during early childhood in the contaminated area of Ukraine. Long-term follow-up is needed to clarify the effects of radiation exposure on autoimmunity reaction in the thyroid.

  3. Chernobyl, fifteen years after; Tchernobyl, 15 ans apres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-04-01

    This work has been constituted around four questions: the future of the Chernobyl site, the damaged reactor, and the sarcophagus around it; the health consequences of the accident on the persons that have worked on the damaged reactor and on the population in the countries the most exposed to fallout,; the situation of contaminated territories around the power plant and their management today; the last question concerns especially the France with the consequences of the radioactive cloud and what we know about the health risks induced by this event. (N.C.)

  4. Lessons learned from post-accident management at Chernobyl: the P.a.r.e.x. project; Retour d'experience sur la gestion post-accidentelle de Tchernobyl: le projet Parex

    Energy Technology Data Exchange (ETDEWEB)

    Heriard Dubreuil, G. [Mutadis Consultants, 75 - Paris (France); Lochard, J.; Bataille, C. [CEPN, 92 - Fontenay aux Roses (France); Ollagnon, H. [AgroParisTech, 75 - Paris (France); Baude, St. [Mutadis, 75 - Paris (France)

    2008-07-15

    Return of experience on Chernobyl post-accident management: the PAREX study Belarus is the country the most affected by the Chernobyl fallouts and is among the most significant experiences in the nuclear post-accident field. Despite specificities inherent to the political and social situation in Belarus, the experience of post-accidental management in this country holds a wealth of lessons in the perspective of preparation to a post-accidental situation in the French and European context. Through the PAREX project (2005-2006), the French Nuclear Safety Authority analysed the return of experience of Chernobyl post-accident management from 1986 to 2005 in order to draw its lessons in the perspective of a preparation policy. The study was led by a group of experts and involved the participation of a pluralistic group of about thirty participants (public authorities, local governments, NGOs, experts, operators). PAREX highlighted the complexity of a situation of long-lasting radioactive contamination (diversity of stakeholders and of dimensions at stake: health, environment, economy, society...). Beyond traditional public crisis management tools and frameworks, post-accident strategies also involves in the longer term a territorial and social response, which relies on local capacities of initiative. Preparation to such process requires experimenting new modes of operation that allow a diversity of local actors to take part to the response to a situation of contamination and to the surveillance system, with the support of public authorities. The conclusions of PAREX include a set of recommendations in this perspective. (authors)

  5. EFFICIENCY OF PROTECTIVE MEASURES TO REDUCE INTERNAL DOSE FROM CAESIUM RADIONUCLIDES FOR THE INHABITANTS OF RADIOACTIVE CONTAMINATION AREA IN THE FIRST YEARS AFTER THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. G. Travnikova

    2012-01-01

    Full Text Available In the paper, we use the data on the content of caesium radionuclides in foodstuffs and in Bryansk region adult inhabitant’s body, on their food ration and its changes during the first years after the Chernobyl accident, and on the measures to protect the population from internal exposure. We calculate dynamics of 137Cs intake in the body and its contents therein, while maintaining a traditional diet and while replacing food products for radiationfree ones. The results show that the actual 137Cs content in the body is usually below the one calculated on the basis of the food ration. It was found out that individual 137Cs contents in the body correlate with the rate of meat, dairy and natural food products consumption and with factors of protection from internal exposure. The efficiency of the protective measures to reduce the intake and the content of caesium radionuclides in the body of inhabitants, as well as the average effective dose in the first years after the accident has been quantitatively assessed.

  6. The study of core melting phenomena in reactor severe accident of PWR

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hong; Jeun, Gyoo Dong; Park, Seh In; Lim, Jae Hyuck; Park, Seong Yong [Hanyang Univ., Seoul (Korea, Republic of); Bang, Kwang Hyun; Kim, Ki Yong [Korea Maritime Univ., Busan (Korea, Republic of)

    1999-03-15

    After TMI-2 accident, it has been paid much attention to severe accidents beyond the design basis accidents and the research on the progress of severe accidents and mitigation and the closure of severe accidents has been actively performed. In particular, a great deal of uncertainties yet exist in the phase of late core melt progression and thus the research on this phase of severe accident progress has a key role in obtaining confidence in severe accident mitigation and nuclear reactor safety. In the present study, physics of late core melt progression, experimental data and the major phenomenological models of computer codes are reviewed and a direction of reducing the uncertainties in the late core melt progression is proposed.

  7. A study on the late core melt progression in pressurized water reactor severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hong; Jeun Gyoo Dong; Bang, Kwang Hyun; Park, Seh In; Lim, Jae Hyuck; Park, Seong Yong [Hanyang Univ., Seoul (Korea, Republic of); Back, Hyung Hmm [Korea Maritime Univ., Busan (Korea, Republic of)

    1998-03-15

    After TMI-2 accidents, it has been paid much attention to severe accidents beyond the design basis accidents and the research on the progress of severe accidents and mitigation and the closure of severe accidents has been actively performed. In particular, a great deal of uncertainties yet exist in the phase of late core melt progression and thus the research on this phase of severe accident progress has a key role in obtaining in severe accident mitigation and nuclear reactor safety. In the present study, physics of late core melt progression, experimental data and the major phenomenological models of computer codes are reviewed and a direction of reducing the uncertainties in the late core melt progression os proposed.

  8. A study on the recriticality possibilities of fast reactor cores after a hypothetical core meltdown accident

    Energy Technology Data Exchange (ETDEWEB)

    Na, Byung Chan; Han, Do Hee; Kim, Young Cheol

    1997-04-01

    The preliminary and parametric sensitivity study on recriticality risk of fast reactor cores after a hypothetical total core meltdown accident was performed. Only the neutronic aspects of the accident was considered for this study, independent of the accident scenario. Estimation was made for the quantities of molten fuel which must be ejected out of the core in order to assure a sub-critical state. Diverse parameters were examined: molten pool type (homogenized or stratified), fuel temperature, conditions of the reactor core, core size (small or large), and fuel type (oxide, nitride, metal) (author). 7 refs.

  9. THE ROLE OF BELARUS NATIONAL COMMISSION ON RADIATION PROTECTION IN THE MINIMIZATION OF CONSEQUENCES OF THE ACCIDENT AT THE CHERNOBYL NUCLEAR POWER PLANT

    Directory of Open Access Journals (Sweden)

    A. N. Stozharov

    2016-01-01

    Full Text Available The Belarus National Commission on Radiation Protection was established in 1991, based on the former Byelorussian Soviet Socialist Republic Supreme Council Resolution. The Commission works out recommendations on the radiation protection to submit to the state authorities, state institutions under the Republic of Belarus Government and state research institutions, reviews and assesses scientific data in the field of radiation protection and makes suggestions in regards of the implementation of the achieved developments. The Commission engages leading scientists and practitioners from Belarus, involved in the provision of the radiation protection and safety in the state. The methodological cornerstone for the Commission activities was chosen to be the committment to the worldwide accepted approach of the nature and magnitude of the undertaken protective measures justification in the field of radiation safety. The Commission adheres the ALARA optimization criteria as the core of the aforementioned approach. The Commission has also submited to the Government a number of developments which were crucial in the highest level managerial decisions elaboration. The latter impacted directly the state tactics and strategy in the environmental, health and social consequences of the Chernobyl disaster minimization. Following the recommendations of the international institutions (ICRP, IAEA, UNSCEAR, FAO/WHO, developments of the colleagues in the Russian Federation, Ukraine and the local regional experience, the Commission proceeds with the expert observation of the ongoing protective measures to reduce the radiation impact and population exposure resulted from the Chernobyl accident, is actively occupied in the radiation safety ensuring at the Belarussian nuclear power plant being under construction, much contributes to elaboration of the new version of the state Law “On Radiation Protection of Population” and other regulatory documents.

  10. RADIOLOGICAL SITUATION IN UKRAINE AFTER CHERNOBYL ACCIDENT AND OPTIMIZATION OF THE COUNTERMEASURES APPLICATION AT THE PRESENT STAGE

    Directory of Open Access Journals (Sweden)

    V. A. Kashparov

    2009-01-01

    Full Text Available The present radiological situation in the agricultural production of Ukraine is considered and analyzed. On the basis of optimization of the countermeasures application the approaches are proposed which would guarantee the compliance of the agricultural production with the corresponding State hygienic regulations, as well as reduction of the effective exposure dose to population below the approved limits. Taking into account the lately growing interest to radiation protection of not only human, but the environment as well, the results of the studies of frequency of the radiobiological effects of chronic irradiation to plantations of Scots pine in the Chernobyl exclusion zone depending on the levels of the dose to the trees' apical meristem are presented.

  11. On the possible physical mechanism of Chernobyl catastrophe and the unsoundness of official conclusion

    CERN Document Server

    Rukhadze, A A; Filippov, D V

    2003-01-01

    The official conclusion about the origin and mechanism of the Chernobyl catastrophe is shown to essentially contradict experimental facts available from the accident. In the frame of existing physical models of nuclear fission reactor, it is shown analytically that under conditions of the accident the period of runaway of reactor at the fourth power generating unit of the Chernobyl Nuclear Power Plant (CNPP) should be either 10 times slower or 100 times faster than that observed. A self-consistent hypothesis is suggested for the probable birth of magnetic charges, during the turbine generator test under it's own momentum test, at the fourth power generating unit of CNPP, and for the impact of these charges on the reactivity coefficient.

  12. Simulation of the Lower Head Boiling Water Reactor Vessel in a Severe Accident

    Directory of Open Access Journals (Sweden)

    Alejandro Nuñez-Carrera

    2012-01-01

    Full Text Available The objective of this paper is the simulation and analysis of the BoilingWater Reactor (BWR lower head during a severe accident. The COUPLE computer code was used in this work to model the heatup of the reactor core material that slumps in the lower head of the reactor pressure vessel. The prediction of the lower head failure is an important issue in the severe accidents field, due to the accident progression and the radiological consequences that are completely different with or without the failure of the Reactor Pressure Vessel (RPV. The release of molten material to the primary containment and the possibility of steam explosion may produce the failure of the primary containment with high radiological consequences. Then, it is important to have a detailed model in order to predict the behavior of the reactor vessel lower head in a severe accident. In this paper, a hypothetical simulation of a Loss of Coolant Accident (LOCA with simultaneous loss of off-site power and without injection of cooling water is presented with the proposal to evaluate the temperature distribution and heatup of the lower part of the RPV. The SCDAPSIM/RELAP5 3.2 code was used to build the BWR model and conduct the numerical simulation.

  13. Thyroid exposure of Belarusian and Ukrainian children due to the Chernobyl accident and resulting thyroid cancer risk. Final report of BfS project StSch 4240

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P.; Meckbach, R.; Ulanovski, A.; Schotola, C.; Proehl, G. [GSF-Institute of Radiation Protection, Neuherberg (Germany); Kenigsberg, J.; Buglova, E.; Kruk, J. [Institute of Radiation Medicine and Endocrinology, Minsk (Belarus); Likhtarev, I.; Kovgan, L.; Vavilov, S.; Chepurniy, M. [Ukrainian Radiation Protection Inst., Kyiv (Ukraine); Tronko, M.; Bogdanova, T. [Institute of Endocrinolgoy and Metabolism of the Academy of Medical Sciences of Ukraine, Kyiv (Ukraine); Shinkarev, S.; Gavrilin, Y. [All-Russian Public Organization of Invalids ' Chernobylets' , Scientific Center ' FENIX' , Moscow (Russian Federation); Demidchik, Y. [Thyroid Cancer Center, Minsk (Belarus)

    2005-07-01

    Main objectives of the BfS Project StSch4240 Thyroid Exposure of Belarusian and Ukrainian Children due to the Chernobyl Accident and Resulting Thyroid Cancer Risk were: to establish improved estimates of average thyroid dose for both genders and for each birth-year cohort of the period 1968 - 1985 in Ukrainian and Belarusian settlements, in which more than 10 measurements of the {sup 131}I activity in the human thyroid have been performed in May/June 1986, to explore, whether this dosimetric database can be extended to neighboring settlements, to establish improved estimates of average thyroid dose for both genders and for each birth-year cohort of the period 1968 - 1985 in Ukrainian and Belarusian oblasts (regions) and larger cities, to document the thyroid cancer incidence for the period 1986 - 2001 in Ukraine and Belarus and describe morphological characteristics of the cancer cases, to assess the contribution of the baseline incidence to the total thyroid cancer incidence in the two countries and identify regional and temporal dependencies, to perform analyses of excess risks in settlements with more than 10 measurements of the {sup 131}I activity in the human thyroid. The project has been conducted in the period 6 December 1999 to 31 March 2004. (orig.)

  14. Dose reconstruction by EPR spectroscopy of tooth enamel: application to the population of Zaborie village exposed to high radioactive contamination after the Chernobyl accident.

    Science.gov (United States)

    Ivannikov, A I; Gaillard-Lecanu, E; Trompier, F; Stepanenko, V F; Skvortsov, V G; Borysheva, N B; Tikunov, D D; Petin, D V

    2004-02-01

    Individual irradiation doses were determined by electron paramagnetic resonance spectroscopy of the tooth enamel of the inhabitants of Zaborie, the most contaminated inhabited settlement not evacuated after the Chernobyl accident. Dose determination was performed using a specially developed automatic spectrum processing procedure. Spectrum processing was carried out in different operating modes, and average results were taken in order to reduce the contribution of uncertainty in dose determination caused by spectrum processing. The absorbed doses determined in enamel were corrected to take into account the contribution of natural background radiation and to determine the individual excess dose due to radioactive contamination of the territory. Individual excess doses are compared to calculated individualized doses to teeth, estimated using the local radioactive contamination levels, dose rates, and information concerning individual behavior. The individual excess doses measured by electron paramagnetic resonance spectroscopy and the calculated individualized doses are fully independent. Mean square variation between results of two methods was found to be 34 mGy, which is consistent with error estimation for both methods. This result can validate both the methodology of signal processing presented here when using electron paramagnetic resonance dosimetry of tooth enamel for low doses and the methodology of individualized dose calculation.

  15. Risk assessment of a pressurized water reactor for Class 3-8 accidents

    Energy Technology Data Exchange (ETDEWEB)

    Hall, R.E.

    1979-10-01

    An assessment has been made of the impact on societal risk of Class 3-8 accident sequences as defined by Appendix D to 10 CFR50. The present analysis concentrates on a pressurized water reactor and utilizes realistic assumptions when practical. Conclusions are drawn as to the relative importance of the analyzed accidents and their impact on the development of a complete societal risk curve. 65 refs., 61 figs., 37 tabs.

  16. [The assessment of accumulated internal irradiation doses of the inhabitants of the populated areas in Republik Belarus after Chernobyl accident].

    Science.gov (United States)

    Chunikhin, L A; Drozdov, D N

    2012-01-01

    A new system of evaluation methods has been developed for the assessment of the accumulated internal irradiation doses in the inhabitants of the populated areas of the Republic of Belarus that were contaminated by the Chernobyl radionuclides. The system is based on the results of WBC measurements. The model is based on the WBC-results of the State Dosimetric Register for the period of 1987-2010. The dose assessment model is based on the classification of the populated areas, on the regional features of the soils through which 137Cs can enter into the locally grown and produced foods. The model is also based on building the regressive correlations of accumulated internal doses to the contamination density of the territory of a populated area. Such regressive correlations are made for each region. The influence of indirect factors of dose forming was taken into consideration in the dose assessment. Among these factors are the population of the area, and the amount of forested territory around it, which were taken as correction coefficients. The coefficients were determined from the regressive correlation of the correction coefficients to a specific area of forest for each region. So called "countermeasure factor" was used for specification of other model results.

  17. Increased leukemia risk in Chernobyl cleanup workers

    Science.gov (United States)

    A new study found a significantly elevated risk for chronic lymphocytic leukemia among workers who were engaged in recovery and clean-up activities following the Chernobyl power plant accident in 1986.

  18. Fission product release phenomena during core melt accidents in metal fueled heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, P G; Hyder, M L; Monson, P R; Randolph, H W [Westinghouse Savannah River Co., Aiken, SC (USA); Hagrman, D L [EG and G Idaho, Inc., Idaho Falls, ID (USA); McClure, P R; Leonard, M T [Science Applications International Corp., Albuquerque, NM (USA)

    1990-01-01

    The phenomena that determine fission product release rates from a core melting accident in a metal-fueled, heavy water reactor are described in this paper. This information is obtained from the analysis of the current metal fuel experimental data base and from the results of analytical calculations. Experimental programs in place at the Savannah River Site are described that will provide information to resolve uncertainties in the data base. The results of the experiments will be incorporated into new severe accident computer codes recently developed for this reactor design. 47 refs., 4 figs.

  19. Computer system for the assessment of radiation situation in the cases of radiological accidents and extreme weather conditions in the Chernobyl exclusion zone

    Energy Technology Data Exchange (ETDEWEB)

    Talerko, M.; Garger, E.; Kuzmenko, A. [Institute for Safety Problems of Nuclear Power Plants (Ukraine)

    2014-07-01

    Radiation situation within the Chernobyl Exclusion Zone (ChEZ) is determined by high radionuclides contamination of the land surface formed after the 1986 accident, as well as the presence of a number of potentially hazardous objects (the 'Shelter' object, the Interim Spent Nuclear Fuel Dry Storage Facility ISF-1, radioactive waste disposal sites, radioactive waste temporary localization sites etc.). The air concentration of radionuclides over the ChEZ territory and radiation exposure of personnel are influenced by natural and anthropogenic factors: variable weather conditions, forest fires, construction and excavation activity etc. The comprehensive radiation monitoring and early warning system in the ChEZ was established under financial support of European Commission in 2011. It involves the computer system developed for assessment and prediction of radiological emergencies consequences in the ChEZ ensuring the protection of personnel and the population living near its borders. The system assesses radiation situation under both normal conditions in the ChEZ and radiological emergencies which result in considerable radionuclides emission into the air (accidents at radiation hazardous objects, extreme weather conditions). Three different types of radionuclides release sources can be considered in the software package. So it is based on a set of different models of emission, atmospheric transport and deposition of radionuclides: 1) mesoscale model of radionuclide atmospheric transport LEDI for calculations of the radionuclides emission from stacks and buildings; 2) model of atmospheric transport and deposition of radionuclides due to anthropogenic resuspension from contaminated area (area surface source model) as a result of construction and excavation activity, heavy traffic etc.; 3) model of resuspension, atmospheric transport and deposition of radionuclides during grassland and forest fires in the ChEZ. The system calculates the volume and surface

  20. Steady-state and loss-of-pumping accident analyses of the Savannah River new production reactor representative design

    Energy Technology Data Exchange (ETDEWEB)

    Pryor, R.J.; Maloney, K.J.

    1990-10-01

    This document contains the steady-state and loss-of-pumping accident analysis of the representative design for the Savannah River heavy water new production reactor. A description of the reactor system and computer input model, the results of the steady-state analysis, and the results of four loss-of-pumping accident calculations are presented. 5 refs., 37 figs., 4 tabs.

  1. Review of psychological consequences of nuclear accidents and empirical study on peoples reactions to radiation protection activities in an imagined situation.; Katsaus ydinonnettomuuksien psykologisiin seurauksiin sekae empiirinen tutkimus saeteilysuojelutoimenpiteiden vaikutuksista kaeyttaeytymiseen kuvitteelisessa tilanteessa

    Energy Technology Data Exchange (ETDEWEB)

    Haukkala, A.; Eraenen, L. [Helsinki Univ. (Finland). Dept. of Social Psychology

    1994-10-01

    The report consist of two parts: a review of studies on psychological consequences of nuclear and radiation accidents in population and an empirical study of peoples reactions to protection actions in an event of hypothetical accident. Review is based on research results from two nuclear reactor accidents (Three Mile Island 1979, Chernobyl 1986) and a radiation accident in Goiania, Brazil 1987. (53 refs, 2 figs.,7 tabs.).

  2. [The characteristics of the clinical course of rheumatic diseases in persons subjected to the effect of ionizing radiation after the accident at the Chernobyl Atomic Electric Power Station].

    Science.gov (United States)

    Babynina, L Ia; Bentsa, T M; Pravdivaia, V F

    1998-01-01

    Results are submitted of clinical, laboratory and immunological studies in patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic scleroderma (SSD), with n = 386, 35, 23 respectively, who had been exposed to ionizing radiation from the ChPP reactor accident. In the above patients, serum interferon (SI) levels were found out to be increased while those of natural killer cells (NKs) decreased by comparison with healthy donors; NKs appeared to be significantly lower (P < 0.001) in SLE and SSD patients than they were in RA ones and healthy subjects.

  3. Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendix XI. Analysis of comments on the draft WASH-1400 report. [PWR and BWR

    Energy Technology Data Exchange (ETDEWEB)

    1975-10-01

    Information is presented concerning comments on reactor safety by governmental agencies and civilian organizations; reactor safety study methodology; consequence model; probability of accident sequences; and various accident conditions.

  4. Consequences of tritium release to water pathways from postulated accidents in a DOE production reactor (U)

    Energy Technology Data Exchange (ETDEWEB)

    O' Kula, K.R.; Olson, R.L.; Hamby, D.M. (Savannah River Lab., Aiken, SC (United States))

    1992-03-01

    A full-scale PRA of a DOE production reactor has been completed that considers full release of tritium as part of the severe accident source term. Two classes of postulated reactor accidents, a loss-of-moderator pumping accident and a loss-of-coolant accident, are used to bound the expected dose consequence from liquid pathway release. Population doses from the radiological release associated with the two accidents are compared for aqueous discharge and atmospheric release modes. The expectation values of the distribution of possible values for the societal effective dose equivalent to the general public, given a tritium release to the atmosphere, is 2.8 person-Sv/PBq (9.9 {times} 10{sup {minus}3} person-rem/Ci). The general public drinking water dose to downstream water consumers is 6.5 {times} 10{sup {minus}2} person-Sv/PBq(2.4 {times} 10{sup {minus}4} person-rem/Ci) for aqueous releases to the surface streams eventually reaching the Savannah River. Negligible doses are calculated for freshwater fish and saltwater invertebrate consumption, irrigation, and recreational use of the river, given that an aqueous release is assumed to occur. Relative to the balance of fission products released in a hypothetical severe accident, the tritium-related dose is small. This paper suggests that application of regional models (1610 km radius) will indicate larger dose consequences from short-term tritium releases to the atmosphere than from comparable tritium source terms to water pathways.

  5. {sup 137}Cs concentration in meat of wild boars (Sus scrofa) in Croatia a decade and half after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Vilic, M. [Department of Physiology and Radiobiology, The Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb (Croatia)]. E-mail: marinko.vilic@vef.hr; Barisic, D. [Laboratory for Radioecology, Centre for Marine and Environmental Research, Ruder Boskovic Institute, PO Box 160, Bijenicka 54, 10002 Zagreb (Croatia)]. E-mail: dbarisic@irb.hr; Kraljevic, P. [Department of Physiology and Radiobiology, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb (Croatia)]. E-mail: petar.kraljevic@vef.hr; Lulic, S. [Laboratory for Radioecology, Centre for Marine and Environmental Research, Ruder Boskovic Institute, PO Box 160, Bijenicka 54, 10002 Zagreb (Croatia)]. E-mail: lulic@irb.hr

    2005-07-01

    Gamma-spectrometric measurements of {sup 137}Cs activities in meat of wild boars collected in Croatia at several locations with different levels of {sup 137}Cs contamination are presented. Samples were collected during the period between 2000 and 2002, about 15 years after the Chernobyl accident. {sup 137}Cs concentrations ranged over three orders of magnitude: 0.4-611.5 Bq kg{sup -1}. On the basis of these results, {sup 137}Cs concentrations at researched areas could be categorized into three groups: (i) the area of Slavonski Brod, Lipik and Slunj with {sup 137}Cs concentrations in meat of only a few Bq kg{sup -1}; (ii) the area of Vrbovsko and Sirac with {sup 137}Cs concentrations of a few tens of Bq kg{sup -1}; and (iii) the Fuzine area with {sup 137}Cs values in wild boar meat of a few hundreds of Bq kg{sup -1}. In areas with approximately equal contamination level, {sup 137}Cs concentrations in wild boar meat varied over two orders of magnitude. This fact suggests that the main reason for high {sup 137}Cs values in wild boar meat could be due to food consumed by wild boars, and only secondarily in contamination level of area where they live. Intensive mushroom consumption during autumn months could be one of the factors responsible for high {sup 137}Cs values in wild boar meat. An average dose arising from {sup 137}Cs due to ingestion of wild boar meat in Croatia is below radiological health concern except in the area of Fuzine, and only in cases of high annual wild boar meat intake, probably by hunters or members of their families.

  6. Urinary bladder lesions after the chernobyl accident. Immunohistochemical assessment of p53, proliferating cell nuclear antigen, cyclin D1 and p21[sup WAF1/Cip1

    Energy Technology Data Exchange (ETDEWEB)

    Romanenko, A.; Zaparin, W.; Vinnichenko, W.; Vozianov, A. (Academy of Medical Sciences of Ukraine, Kiev (Ukraine)); Lee, C.C.R.; Yamamoto, Shinji; Hori, Taka-aki; Wanibuchi, Hideki; Fukushima, Shoji

    1999-02-01

    During the 11-year period subsequent to the Chernobyl accident, the incidence of urinary bladder cancer in Ukraine has increased from 26.2 to 36.1 per 100,000 population. Cesium-137 ([sup 137]Cs) accounts for 80-90% of the incorporated radioactivity in this population, which has been exposed to long-term, low-dose ionizing radiation, and 80% of the more labile pool of cesium is excreted via the urine. The present study was performed to evaluate the histopathological features and the immunohistochemical status of p53, p21[sup WAF1/Cip1], cyclin D1 and PCNA (proliferating cell nuclear antigen) in urinary bladder mucosa of 55 males (49-92 years old) with benign prostatic hyperplasia who underwent surgery in Kiev, Ukraine, in 1995 and 1996. Group I (28 patients) inhabiting radiocontaminated areas of the country, group II (17 patients) from Kiev city with less radiocontamination and a control group III (10 patients) living in so-called ''clean'' areas of Ukraine were compared. In groups I and II, an increase in multiple areas of moderate or severe dysplasia or carcinoma in situ was seen in 42 (93%) of 45 cases. In addition, two small transitional cell carcinomas were found in one patient in each of groups I and II. Nuclear accumulation of p53, PCNA, cyclin D1, and to a lesser extent p21[sup WAF1/Cip1], was significantly increased in both groups I and II as compared with the control group III, indicating possible transformation events or enhancement of repair activities, that may precede the defect in the regulatory pathway itself, at least in the G1 phase of the cell cycle. Our results suggest that early malignant transformation is taking place in the bladder urothelium of people in the radiocontaminated areas of Ukraine and that this could possibly lead sometime in the future to an increased incidence of urinary bladder cancer. (author)

  7. Chernobyl; Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This report relates the Chernobylsk accident, why following a succession of technical malfunctions and human errors, reactor no. 4 of the Chernobylsk nuclear power plant explodes on April 26. 1986. Radioactive dust, aerosols and gases (including caesium and iodine) are ejected into atmosphere. The regions worst hit are in the immediate vicinity of the plant, but deposits are very uneven, producing a leopard spot type of pattern. Propelled by easterly winds, the radioactive cloud disperses increasingly, scattering deposits over the whole of Europe. At the beginning of May, the cloud arrives in France. the eastern portion of the country is most strongly affected. Ground, water and agriculture are contaminated by caesium deposits in Belarus, Ukraine and Russian Federation. About the contamination in France, ground contamination is slight, fourteen years later, however, it is still detectable. Relative to the impact on health in the vicinity of Chernobylsk plant, it is hard to assess this impact. Among children in Southern Belarus, the number of thyroid cancers has risen one hundred-fold. In France, the doses delivered represents generally less than 1% of the average annual dose from radioactivity of natural origin. But some of the doses received were higher. Today, the protective sarcophagus covering the damaged reactor is fragile. Reactor no.3, still in operation, continues to pose a risk but the shutdown is provided for december 2000. (N.C.)

  8. Reconstruction of {sup 131}I radioactive contamination in Ukraine caused by the Chernobyl accident using atmospheric transport modelling

    Energy Technology Data Exchange (ETDEWEB)

    Talerko, Nikolai [Scientific Center for Radiation Medicine, 53 Melnikov Street, Kyiv 04050 (Ukraine)]. E-mail: ntalerko@mail.ru

    2005-07-01

    The evaluation of {sup 131}I air and ground contamination field formation in the territory of Ukraine was made using the model of atmospheric transport LEDI (Lagrangian-Eulerian DIffusion model). The {sup 131}I atmospheric transport over the territory of Ukraine was simulated during the first 12 days after the accident (from 26 April to 7 May 1986) using real aerological information and rain measurement network data. The airborne {sup 131}I concentration and ground deposition fields were calculated as the database for subsequent thyroid dose reconstruction for inhabitants of radioactive contaminated regions. The small-scale deposition field variability is assessed using data of {sup 137}Cs detailed measurements in the territory of Ukraine. The obtained results are compared with available data of radioiodine daily deposition measurements made at the network of meteorological stations in Ukraine and data of the assessments of {sup 131}I soil contamination obtained from the {sup 129}I measurements.

  9. SUBSTANTIATION OF THE CONCEPT OF TRANSFER TO CONDITIONS OF NORMAL POPULATION ACTIVITY OF THE SETTLEMENTS CONSIDERED TO BE ZONES OF RADIOACTIVE CONTAMINATION AFTER THE CHERNOBYL NPP ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. K. Romanovich

    2016-01-01

    Full Text Available The article contains substantiation of criteria of return of territories with radioactive pollution caused by Chernobyl NPP accident to conditions of normal population activity. It is established that in 12 entities of the Russian Federation (except Bryansk and Kaluga regions all agricultural food produce, including that from the personal part-time farms, corresponds to hygienic specifications. Non- corresponding to the standard SanPiN 2.3.2.1078-01 on 137Cs are part of the milk samples produced at personal part-time farms of the Bryansk region and most of natural foodstuff samples (berries, mushrooms, fish and wild animals meat in Bryansk and Kaluga regions. The content of 137Cs both in agricultural and in wild-growing foodstuff produced at radioactively contaminated territories depends not only on the density of radioactive pollution, but also on the types of soil. The average settlement annual effective dose of population irradiation (AAED90 in the 3700 among 4413 settlements as of 2014 was below 0.3 mSv/year. Only in 713 settlements of Bryansk, Kaluga, Oryol and Tula regions the AAED90 exceeds 0.3 mSv/year. In the Bryansk region, once subject to the greatest radioactive contamination, in 276 settlements AAED90 exceeds 1 mSv/year, and in 8 of them - 5 mSv/year.The legislation of the Russian Federation defines only criteria and requirements for consideration of the suffered territories as zones of radioactive contamination. Requirements on transfer of territories polluted by radiation accidents and their population to normal life activity conditions (regarding the radiological factor are not developed.Radiological criteria are suggested for transfer of the settlements considered to be the zone of radioactive pollution to conditions of normal life activity: average irradiation dose of critical population group: 1.0 mSv per year and lower (AAED crit; decrease of radionuclide soil contamination density to the level enabling to use the territory

  10. Frequency of dicentrics in Ukrainian children and teenagers from areas near Chernobyl 20 years after the nuclear power plant accident; Frecuencia de dicentricos en ninos y adolescentes ucranianos de zonas cercanas a Chernobyl 20 anos despues del accidente de la central nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, A.; Sebastia, N.; Candela, C.; Francesc Barquinero, J.; Soriano, J. M.; Almonacid, M.; Sahuquillo, V.; Alonso, O.; Cervera, J.; Such, E.; Silla, M. A.; Arnal, C.; Villaescusa, J. I.

    2012-07-01

    In this work, frequency of dicentrics in the peripheral blood of 55 children and teenagers from Ukrainian areas affected by the Chernobyl accident are studied, in order to assess the possible existence of chromosomal damage due to radiation, and to estimate absorbed dose through biological dosimetry. A total of 36 dicentric chromosomes found in 53477 analyzed cells reflected a low dicentric frequency (below the baseline limit). From these results, it can be concluded that, within the detection limits of the used technique, no overexposure to radiation was detected in these children. (Author) 18 refs.

  11. Evaluation of LLNL's Nuclear Accident Dosimeters at the CALIBAN Reactor September 2010

    Energy Technology Data Exchange (ETDEWEB)

    Hickman, D P; Wysong, A R; Heinrichs, D P; Wong, C T; Merritt, M J; Topper, J D; Gressmann, F A; Madden, D J

    2011-06-21

    The Lawrence Livermore National Laboratory uses neutron activation elements in a Panasonic TLD holder as a personnel nuclear accident dosimeter (PNAD). The LLNL PNAD has periodically been tested using a Cf-252 neutron source, however until 2009, it was more than 25 years since the PNAD has been tested against a source of neutrons that arise from a reactor generated neutron spectrum that simulates a criticality. In October 2009, LLNL participated in an intercomparison of nuclear accident dosimeters at the CEA Valduc Silene reactor (Hickman, et.al. 2010). In September 2010, LLNL participated in a second intercomparison of nuclear accident dosimeters at CEA Valduc. The reactor generated neutron irradiations for the 2010 exercise were performed at the Caliban reactor. The Caliban results are described in this report. The procedure for measuring the nuclear accident dosimeters in the event of an accident has a solid foundation based on many experimental results and comparisons. The entire process, from receiving the activated NADs to collecting and storing them after counting was executed successfully in a field based operation. Under normal conditions at LLNL, detectors are ready and available 24/7 to perform the necessary measurement of nuclear accident components. Likewise LLNL maintains processing laboratories that are separated from the areas where measurements occur, but contained within the same facility for easy movement from processing area to measurement area. In the event of a loss of LLNL permanent facilities, the Caliban and previous Silene exercises have demonstrated that LLNL can establish field operations that will very good nuclear accident dosimetry results. There are still several aspects of LLNL's nuclear accident dosimetry program that have not been tested or confirmed. For instance, LLNL's method for using of biological samples (blood and hair) has not been verified since the method was first developed in the 1980's. Because LLNL and

  12. [The effect of vitamin- and beta-carotene-enriched products on the vitamin A allowance and the concentration of different carotenoids of the blood serum in victims of the accident at the Chernobyl Atomic Electric Power Station].

    Science.gov (United States)

    Iakushina, L M; Taranova, A G; Pokrovskaia, G R; Shatniuk, L N; Spirichev, V B

    1996-01-01

    The results of clinical trials of efficiency of foods enriched by vitamins and beta-carotene in people suffered from Chernobyl's accident are presented. The level of beta-carotene in clinical diets was the same during trial. Daily consumption of enriched food supplying ingestion of 4-5 mg of beta-carotene increased the level of beta-carotene in serum by 2-4 times. The concentration of total carotenoides in serum was increased by 1.6 times practically at the expense of beta-carotene.

  13. Estimated recurrence frequencies for initiating accident categories associated with the Clinch River Breeder Reactor Plant design

    Energy Technology Data Exchange (ETDEWEB)

    Copus, E R

    1982-04-01

    Estimated recurrence frequencies for each of twenty-five generic LMFBR initiating accident categories were quantified using the Clinch River Breeder Reactor Plant (CRBRP) design. These estimates were obtained using simplified systems fault trees and functional event tree models from the Accident Delineation Study Phase I Final Report coupled with order-of-magnitude estimates for the initiator-dependent failure probabilities of the individual CRBRP engineered safety systems. Twelve distinct protected accident categories where SCRAM is assumed to be successful are estimated to occur at a combined rate of 10/sup -3/ times per year while thirteen unprotected accident categories in which SCRAM fails are estimated to occur at a combined rate on the order of 10/sup -5/ times per year. These estimates are thought to be representative despite the fact that human performance factors, maintenance and repair, as well as input common cause uncertainties, were not treated explicitly. The overall results indicate that for the CRBRP design no single accident category appears to be dominant, nor can any be totally eliminated from further investigation in the areas of accident phenomenology for in-core events and post-accident phenomenology for containment.

  14. Imperfect conformation of experimental and epidemiological data for frequency of RET/РТС gene rearrangements in papillary thyroid carcinoma for the Chernobyl accident

    Directory of Open Access Journals (Sweden)

    Ushenkova L.N.

    2013-12-01

    Full Text Available In an overview and analytical study of the epidemiological data on the frequency of RET/РТС gene rearrangements in sporadic and radiogenic (patients after radiotherapy, residents of contaminated after the Chernobyl disaster areas, victims after the atomic bombings, etc. carcinomas of the thyroid gland were examined. In general, the observed epidemiological laws were confirmed in radiobiology experiments by irradiation of different cultures of thyroid cells and ex vivo with the exception of Chernobyl cohorts. Induction of RET/РТС gene rearrangements by 131l exposure in children carcinomas of Chernobyl residents in mice did not observe too. It is concluded that the situation with the frequency of RET/РТС rearrangements in thyroid carcinoma in Chernobyl cohorts once again confirms the multifactorial nature of the induction and development of these tumors with a contribution of radiation and non-radiation factors (iodine deficiency and different stresses.

  15. Management of a severe accident on a pressurised water reactor in France; La gestion d'un accident grave sur un reacteur a eau sous pression en France

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This brief document defines what a severe accident is on a nuclear reactor, indicates the different failure modes which have been defined (vapour explosion in the reactor vessel, hydrogen explosion, and so on). It describes the management of a core fusion accident for pressurized water reactors, for which a guide has been designed, the GIAG (intervention guide for a severe accident situation). The principles of such an intervention are described, and then the approach for an EPR reactor

  16. A diagnostic system for identifying accident conditions in a nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, T.V., E-mail: santoshiitb@yahoo.co [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai (India); Kumar, M.; Thangamani, I.; Srivastava, A.; Dutta, A.; Verma, V.; Mukhopadhyay, D.; Ganju, S.; Chatterjee, B.; Rao, V.V.S.S.; Lele, H.G.; Ghosh, A.K. [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai (India)

    2011-01-15

    Research highlights: Neural networks based diagnostic system has been developed to identify transients quickly, estimate the source-term and assist the operator to take corrective actions during abnormal situations in 220 MWe PHWRs. The transient data for the break scenarios ranging from 20% to 200% has been generated using RELAP5 and CONTRAN codes. 32 break scenarios of large break LOCA in inlet and outlet reactor headers with and without ECCS have been analyzed using artificial neural networks. A few break scenarios were directly predicted without being trained earlier. Test results obtained from ANN are within the acceptable range. - Abstract: The objective of this study is to develop a system, which assists the operator in identifying an accident quickly using ANNs that diagnoses the accidents based on reactor process parameters, and continuously displays the status of the nuclear reactor. A large database of transient data of reactor process parameters has been generated for reactor core, containment, environmental dispersion and radiological dose to train the ANNs. These data have been generated using various codes e.g., RELAP5-thermal-hydraulics code for the core. The present version of this system is capable of identifying large break LOCA scenarios of 220 MWe Indian PHWRs. The system has been designed to provide the necessary information to the operator to handle emergency situations when the reactor is operating. The diagnostic results obtained from ANNs study are satisfactory.

  17. Post test calculations of a severe accident experiment for VVER-440 reactors by the ATHLET code

    Energy Technology Data Exchange (ETDEWEB)

    Gyoergy, Hunor [Budapest Univ. of Technology and Economics (Hungary). Inst. of Nuclear Techniques (BME NTI); Trosztel, Istvan [Hungarian Academy of Sciences, Budapest (Hungary). Centre for Energy Research (MTA EK)

    2013-09-15

    Severe accident - if no mitigation action is taken - leads to core melt. An effective severe accident management strategy can be the external reactor pressure vessel cooling for corium localization and stabilization. For some time discussion was going on, whether the in-vessel retention can be applied for the VVER-440 type reactors. It had to be demonstrated that the available space between the reactor vessel and biological protection allows sufficient cooling to keep the melted core in the vessel, without the reactor pressure vessel losing its integrity. In order to demonstrate the feasibility of the concept an experimental facility was realized in Hungary. The facility called Cooling Effectiveness on the Reactor External Surface (CERES) is modeling the vessel external surface and the biological protection of Paks NPP. A model of the CERES facility for the ATHLET TH system code was developed. The results of the ATHLET calculation agree well with the measurements showing that the vessel cooling can be insured for a long time in a VVER-440 reactor. (orig.)

  18. Analysis of Moderator System Failure Accidents by Using New Method for Wolsong-1 CANDU 6 Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Dongsik; Kim, Jonghyun; Cho, Cheonhwey [Atomic Creative Technology Co., Ltd., Daejeon (Korea, Republic of); Kim, Sungmin [Korea Hydro and Nuclear Power Co., Ltd., Daejeon (Korea, Republic of)

    2013-05-15

    To reconfirm the safety of moderator system failure accidents, the safety analysis by using the reactor physics code, RFSP-IST, coupled with the thermal hydraulics code, CATHENA is performed additionally. In the present paper, the newly developed analysis method is briefly described and the results obtained from the moderator system failure accident simulations for Wolsong-1 CANDU 6 reactor by using the new method are summarized. The safety analysis of the moderator system failure accidents for Wolsong-1 CANDU 6 reactor was carried out by using the new code system, i. e., CATHENA and RFSP-IST, instead of the non-IST old codes, namely, SMOKIN G-2 and MODSTBOIL. The analysis results by using the new method revealed as same with the results by using the old method that the fuel integrity is warranted because the localized power peak remained well below the limits and, most importantly, the reactor operation enters into the self-shutdown mode due to the substantial loss of moderator D{sub 2}O inventory from the moderator system. In the analysis results obtained by using the old method, it was predicted that the ROP trip conditions occurred for the transient cases which are also studied in the present paper. But, in the new method, it was found that the ROP trip conditions did not occur. Consequently, in the safety analysis performed additionally by using the new method, the safety of moderator system failure accidents was reassured. In the future, the new analysis method by using the IST codes instead of the non-IST old codes for the moderator system failure accidents is strongly recommended.

  19. Lessons from Chernobyl.

    Science.gov (United States)

    Takamura, Noboru; Yamashita, Shunichi

    2011-01-01

    The Chernobyl disaster on April 26th, 1986, led to the emission of radioactive substances such as iodine-131 and radioactive cesium. As the Soviet Union did not control food distribution and intake, residents were exposed to high levels of internal radiation, leading to the internal radiation exposure of the thyroid gland by iodine-131. As a result, the number of people who had thyroid cancer increased drastically among those who had been under 15 years old at the time of the accident. The age predilection is about to move to 25 or older. However, there has been no scientific evidence of impacts for solid tumor other than thyroid cancer, leukemia, benign diseases, or inheritance including unborn babies. On the other hand, the accident was thought to have caused social unrest and mental damage which had far more impact than that caused by radiation exposure. In this paper, we would like to summarize the impacts on the health of the people in Chernobyl compared to those caused by the accident at the Fukushima Daiichi Nuclear Power Plant.

  20. Lessons from Chernobyl

    OpenAIRE

    Takamura, Noboru; Yamashita, Shunichi

    2011-01-01

    The Chernobyl disaster on April 26th, 1986, led to the emission of radioactive substances such as iodine-131 and radioactive cesium. As the Soviet Union did not control food distribution and intake, residents were exposed to high levels of internal radiation, leading to the internal radiation exposure of the thyroid gland by iodine-131. As a result, the number of people who had thyroid cancer increased drastically among those who had been under 15 years old at the time of the accident. The ag...

  1. [Prognosis of dynamics and risk of exceeding permissible levels of 137Cs and 90Sr contents in fish in the Kiev Reservoir at the late phase of the Chernobyl accident].

    Science.gov (United States)

    2013-01-01

    On the basis of the radionuclide specific activity measurements made on 832 samples of fish in 2009-2011 and taking into account literature data, the parameters of the stochastic model have been derived to describe the 137Cs and 90Sr contents in typical commercial fish species in the Kiev Reservoir at the late phase of the Chernobyl accident, including: statistical variability, seasonal changes and monotonous long-term trends. At any fixed moment of the year the standard deviations of logarithms of the 137Cs and 90Sr specific activities in carnivorous and benthophage fish species do not reliably differ, making up at average 0.4. The maximum vari- ation of the 137Cs specific activity (a four-fold decrease from April to November) was observed in pike. The obtained values of the ecological half-life periods for 137Cs and 90Sr (1.3-14 years) in fish of the Kiev reservoir in 2002-2012 were significantly lower than both the radioactive decay periods and the estimates of the IAEA Chernobyl Forum. Based on the obtained model parameters, the dynamics of the 137Cs and 90Sr specific ac- tivities in main commercial fish of the Kiev reservoir has been described and the risk of exceeding the permis- sible levels of these radionuclides in fish at the late phase of the Chernobyl accident has been estimated. Now the risk of catching fish with the specific activities of 137Cs and 90Sr above the permissible levels (150 Bq/kg and 35 Bq/kg, respectively) does not exceed 10% (except perch in the spring spawning period that is banned for fishing in Ukraine). Corresponding risks for roach, white bream and rudd are less than 0.1%.

  2. Reactor Core Coolability Analysis during Hypothesized Severe Accidents of OPR1000

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yongjae; Seo, Seungwon; Kim, Sung Joong [Hanyang University, Seoul (Korea, Republic of); Ha, Kwang Soon; Kim, Hwan-Yeol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    Assessment of the safety features over the hypothesized severe accidents may be performed experimentally or numerically. Due to the considerable time and expenditures, experimental assessment is implemented only to the limited cases. Therefore numerical assessment has played a major role in revisiting severe accident analysis of the existing or newly designed power plants. Computer codes for the numerical analysis of severe accidents are categorized as the fast running integral code and detailed code. Fast running integral codes are characterized by a well-balanced combination of detailed and simplified models for the simulation of the relevant phenomena within an NPP in the case of a severe accident. MAAP, MELCOR and ASTEC belong to the examples of fast running integral codes. Detailed code is to model as far as possible all relevant phenomena in detail by mechanistic models. The examples of detailed code is SCDAP/RELAP5. Using the MELCOR, Carbajo. investigated sensitivity studies of Station Black Out (SBO) using the MELCOR for Peach Bottom BWR. Park et al. conduct regulatory research of the PWR severe accident. Ahn et al. research sensitivity analysis of the severe accident for APR1400 with MELCOR 1.8.4. Lee et al. investigated RCS depressurization strategy and developed a core coolability map for independent scenarios of Small Break Loss-of-Coolant Accident (SBLOCA), SBO, and Total Loss of Feed Water (TLOFW). In this study, three initiating cases were selected, which are SBLOCA without SI, SBO, and TLOFW. The initiating cases exhibit the highest probability of transitioning into core damage according to PSA 1 of OPR 1000. The objective of this study is to investigate the reactor core coolability during hypothesized severe accidents of OPR1000. As a representative indicator, we have employed Jakob number and developed JaCET and JaMCT using the MELCOR simulation. Although the RCS pressures for the respective accident scenarios were different, the JaMCT and Ja

  3. Severe accident improvements for Carem-25 to arrest reactor vessel meltdown sequences

    Energy Technology Data Exchange (ETDEWEB)

    Poier Baez, L.E.; Nunez Mac Leod, J.E.; Baron, J.H. [Cuyo National University, Engineering Faculty, Mendoza (Argentina)

    2001-07-01

    Given an accident sequence, that leads to sustained uncovering of the core, the progression of core damage involves several complex phenomena. The progression of these phenomena can lead to a breach of the reactor vessel followed by the discharge of molten core materials to the containment. Advanced nuclear reactor designs, such as the CAREM reactor, include several improvements related to safety issues either enhancing the passive safety functions or allowing plant operators more time to undertake different management actions against radioactive releases to the environment. In the development of the nuclear power plant CAREM, the possibility of including a passive metallic in-vessel container in its design is being considered, to arrest the reactor pressure vessel meltdown sequence during a core damaging event, and thereof prevent its failure. The paper comprises the first analyses, via numerical simulation, for the conceptual design of such a container type; furthermore, the paper addresses simulation model characteristics helping to establish geometrical dimensions, materials and container compatibility with power plant engineering features. The paper also presents the first model developed to analyze the complex relocation phenomena in the core of CAREM during a severe accident sequence caused by a loss of coolant. The PC version of MELCOR 1.8.4 code has been used to predict the transient behavior of core parameters. MELCOR is a fully integrated relatively fast running code that models the progression of accidents in light water reactor power plants. This paper presents reactor variables behavior during the first hours of the event being studied, giving preliminary conclusions about the use and capability of a metallic in-vessel core catcher. (authors)

  4. From Chernobyl to Fukushima: the effect of low doses; De Tchernobyl a Fukushima. L'effet des faibles doses

    Energy Technology Data Exchange (ETDEWEB)

    Aurengo, A.

    2011-07-01

    This Power Point presentation describes the Fukushima's reactors, recalls some data about the earthquake and tsunami, and indicates their consequences for the operation of the power station (notably the loss of cooling means). It identifies some design errors for the Chernobyl's and Fukushima's power stations, outlines differences between these two cases. It gives assessment of doses receives by external irradiation around Fukushima, of the dose rate evolution, of the sea contamination. It gives some data about the Chernobyl accident (radioactivity evolution). After some data about health consequences of Chernobyl, health risks and more particularly biological risks associated to low doses are described. Protection measures are evoked, as well as psycho-social impacts

  5. Accident Analysis for the NIST Research Reactor Before and After Fuel Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Baek J.; Diamond D.; Cuadra, A.; Hanson, A.L.; Cheng, L-Y.; Brown, N.R.

    2012-09-30

    Postulated accidents have been analyzed for the 20 MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The analysis has been carried out for the present core, which contains high enriched uranium (HEU) fuel and for a proposed equilibrium core with low enriched uranium (LEU) fuel. The analyses employ state-of-the-art calculational methods. Three-dimensional Monte Carlo neutron transport calculations were performed with the MCNPX code to determine homogenized fuel compositions in the lower and upper halves of each fuel element and to determine the resulting neutronic properties of the core. The accident analysis employed a model of the primary loop with the RELAP5 code. The model includes the primary pumps, shutdown pumps outlet valves, heat exchanger, fuel elements, and flow channels for both the six inner and twenty-four outer fuel elements. Evaluations were performed for the following accidents: (1) control rod withdrawal startup accident, (2) maximum reactivity insertion accident, (3) loss-of-flow accident resulting from loss of electrical power with an assumption of failure of shutdown cooling pumps, (4) loss-of-flow accident resulting from a primary pump seizure, and (5) loss-of-flow accident resulting from inadvertent throttling of a flow control valve. In addition, natural circulation cooling at low power operation was analyzed. The analysis shows that the conversion will not lead to significant changes in the safety analysis and the calculated minimum critical heat flux ratio and maximum clad temperature assure that there is adequate margin to fuel failure.

  6. A study of core melting phenomena in reactor severe accident of PWR

    Energy Technology Data Exchange (ETDEWEB)

    Jeun, Gyoo Dong; Park, Shane; Kim, Jong Sun; Kim, Sung Joong [Hanyang Univ., Seoul (Korea, Republic of); Kim, Jin Man [Korea Maritime Univ., Busan (Korea, Republic of)

    2001-03-15

    In the 4th year, SCDAP/RELAP5 best estimate input data obtained from the TMI-2 accident analysis were applied to the analysis of domestic nuclear power plant. Ulchin nuclear power plant unit 3, 4 were selected as reference plant and steam generator tube rupture, station blackout SCDAP/RELAP5 calculation were performed to verify the adequacy of the best estimate input parameters and the adequacy of related models. Also, System 80+ EVSE simulation was executed to study steam explosion phenomena in the reactor cavity and EVSE load test was performed on the simplified reactor cavity geometry using TRACER-II code.

  7. Safety Re-evaluation of Kyoto University Research Reactor by reflecting the Accident of Fukushima Daiichi Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, K.; Yamamoto, T. [Kyoto Univ., Kyoto (Japan)

    2013-07-01

    Kyoto University Research Reactor (KUR) is a light-water moderated tank-type reactor operated at rated thermal power of 5MW. After the accident of Fukushima Daiichi nuclear power plant, we have settled a 40-ton water tank near the reactor room, and prepared a mobile fire pump and a mobile power generator as additional safety measures for beyond design basis accidents (BDBAs). We also have conducted the safety re-evaluation of KUR, and confirmed that the integrity of KUR fuels could be kept against the BDBA with the use of the additional safety measures when the several restrictions were imposed on the reactor operation.

  8. Examination of offsite radiological emergency measures for nuclear reactor accidents involving core melt. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, D.C.; McGrath, P.E.; Rasmussen, N.C.

    1978-06-01

    Evacuation, sheltering followed by population relocation, and iodine prophylaxis are evaluated as offsite public protective measures in response to nuclear reactor accidents involving core-melt. Evaluations were conducted using a modified version of the Reactor Safety Study consequence model. Models representing each measure were developed and are discussed. Potential PWR core-melt radioactive material releases are separated into two categories, ''Melt-through'' and ''Atmospheric,'' based upon the mode of containment failure. Protective measures are examined and compared for each category in terms of projected doses to the whole body and thyroid. Measures for ''Atmospheric'' accidents are also examined in terms of their influence on the occurrence of public health effects.

  9. Advanced Fuels Campaign Light Water Reactor Accident Tolerant Fuel Performance Metrics

    Energy Technology Data Exchange (ETDEWEB)

    Brad Merrill; Melissa Teague; Robert Youngblood; Larry Ott; Kevin Robb; Michael Todosow; Chris Stanek; Mitchell Farmer; Michael Billone; Robert Montgomery; Nicholas Brown; Shannon Bragg-Sitton

    2014-02-01

    The safe, reliable and economic operation of the nation’s nuclear power reactor fleet has always been a top priority for the United States’ nuclear industry. As a result, continual improvement of technology, including advanced materials and nuclear fuels, remains central to industry’s success. Decades of research combined with continual operation have produced steady advancements in technology and yielded an extensive base of data, experience, and knowledge on light water reactor (LWR) fuel performance under both normal and accident conditions. In 2011, following the Great East Japan Earthquake, resulting tsunami, and subsequent damage to the Fukushima Daiichi nuclear power plant complex, enhancing the accident tolerance of LWRs became a topic of serious discussion. As a result of direction from the U.S. Congress, the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) initiated an Accident Tolerant Fuel (ATF) Development program. The complex multiphysics behavior of LWR nuclear fuel makes defining specific material or design improvements difficult; as such, establishing qualitative attributes is critical to guide the design and development of fuels and cladding with enhanced accident tolerance. This report summarizes a common set of technical evaluation metrics to aid in the optimization and down selection of candidate designs. As used herein, “metrics” describe a set of technical bases by which multiple concepts can be fairly evaluated against a common baseline and against one another. Furthermore, this report describes a proposed technical evaluation methodology that can be applied to assess the ability of each concept to meet performance and safety goals relative to the current UO2 – zirconium alloy system and relative to one another. The resultant ranked evaluation can then inform concept down-selection, such that the most promising accident tolerant fuel design option(s) can continue to be developed for lead test rod or lead test assembly

  10. Evaluation of sanitary consequences of Chernobyl accident in France: epidemiological monitoring device, state of knowledge, evaluation of risks and perspectives; Evaluation des consequences sanitaires de l'accident de Tchernobyl en France: dispositif de surveillance epidemiologique, etat des connaissances, evaluation des risques et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Verger, P.; Champion, D.; Gourmelon, P.; Hubert, Ph.; Joly, J.; Renaud, Ph.; Tirmarche, M.; Vidal, M. [CEA/Fontenay-aux-Roses, Inst. de Protection et de Surete Nucleaire, IPSN, 92 (France); Cherie-Challine, L.; Boutou, O.; Isnard, H.; Jouan, M.; Pirard, Ph. [Institut National de Veille Sanitaire, 94 - Saint-Maurice (France)

    2000-12-01

    The objectives of this document are firstly, to present the situation of knowledge both on the sanitary consequences of the Chernobyl accident and on the risk factors of thyroid cancers, these ones constituting one of the most principal consequences observed in Belarus, in Ukraine and Russia; secondly, the give the principal system contributing to the epidemiological surveillance of effects coming from a exposure to ionizing radiations, in France and to give the knowledge on incidence and mortality of thyroid cancer in France; thirdly, to discuss the pertinence and the feasibility of epidemiological approaches that could be considered to answer questions that the public and authorities ask relatively to the sanitary consequences of Chernobyl accident in France; fourthly to male a calculation of thyroid cancer risk in relation with Chernobyl fallout in France from works and studies made from 1986 on the consequences of this disaster in terms of radioecology and dosimetry at the national level. Besides, the improvement of thyroid cancer surveillance is also tackled. (N.C.)

  11. Observations of fallout from the Fukushima reactor accident in San Francisco Bay area rainwater.

    Directory of Open Access Journals (Sweden)

    Eric B Norman

    Full Text Available We have observed fallout from the recent Fukushima Dai-ichi reactor accident in samples of rainwater collected in the San Francisco Bay area. Gamma ray spectra measured from these samples show clear evidence of fission products--(131,132I, (132Te, and (134,137Cs. The activity levels we have measured for these isotopes are very low and pose no health risk to the public.

  12. Observations of Fallout from the Fukushima Reactor Accident in San Francisco Bay Area Rainwater

    CERN Document Server

    Norman, Eric B; Chodash, Perry A

    2011-01-01

    We have observed fallout from the recent Fukushima Dai-ichi reactor accident in samples of rainwater collected in the San Francisco Bay area. Gamma ray spectra measured from these samples show clear evidence of fission products - 131,132I, 132Te, and 134,137Cs. The activity levels we have measured for these isotopes are very low and pose no health risk to the public.

  13. Consequences of tritium release to water pathways from postulated accidents in a DOE production reactor

    Energy Technology Data Exchange (ETDEWEB)

    O' Kula, K.R.; Olson, R.L.; Hamby, D.M.

    1991-01-01

    A full-scale PRA of a DOE production reactor has been completed that considers full release of tritium as part of the severe accident source term. Two classes of postulated reactor accidents, a loss-of-moderator pumping accident and a loss-of-coolant accident, are used to bound the expected dose consequence from liquid pathway release. Population doses from the radiological release associated with the two accidents are compared for aqueous discharge and atmospheric release modes. The expectation values of the distribution of possible values for the societal effective dose equivalent to the general public, given a tritium release to the atmosphere, is 2.8 person-Sv/PBq (9.9 {times} 10{sup {minus}3} person-rem/Ci). The general public drinking water dose to downstream water consumers is 6.5 {times} 10{sup {minus}2} person-Sv/Pbq (2.4 {times} 10{sup {minus}4} person-rem/Ci) for aqueous releases to the surface streams eventually reaching the Savannah River. Negligible doses are calculated for freshwater fish and saltwater invertebrate consumption, irrigation, and recreational use of the river, given that an aqueous release is assumed to occur. Relative to the balance of fission products released in a hypothetical severe accident, the tritium-related dose is small. This study suggests that application of regional models (1610 km radius) will indicate larger dose consequences from short-term tritium release to the atmosphere than from comparable tritium source terms to water pathways. However, the water pathways assessment is clearly site-specific, and the overall aqueous dose will be dependent on downstream receptor populations and uses of the river.

  14. Consequences of tritium release to water pathways from postulated accidents in a DOE production reactor

    Energy Technology Data Exchange (ETDEWEB)

    O`Kula, K.R.; Olson, R.L.; Hamby, D.M.

    1991-12-31

    A full-scale PRA of a DOE production reactor has been completed that considers full release of tritium as part of the severe accident source term. Two classes of postulated reactor accidents, a loss-of-moderator pumping accident and a loss-of-coolant accident, are used to bound the expected dose consequence from liquid pathway release. Population doses from the radiological release associated with the two accidents are compared for aqueous discharge and atmospheric release modes. The expectation values of the distribution of possible values for the societal effective dose equivalent to the general public, given a tritium release to the atmosphere, is 2.8 person-Sv/PBq (9.9 {times} 10{sup {minus}3} person-rem/Ci). The general public drinking water dose to downstream water consumers is 6.5 {times} 10{sup {minus}2} person-Sv/Pbq (2.4 {times} 10{sup {minus}4} person-rem/Ci) for aqueous releases to the surface streams eventually reaching the Savannah River. Negligible doses are calculated for freshwater fish and saltwater invertebrate consumption, irrigation, and recreational use of the river, given that an aqueous release is assumed to occur. Relative to the balance of fission products released in a hypothetical severe accident, the tritium-related dose is small. This study suggests that application of regional models (1610 km radius) will indicate larger dose consequences from short-term tritium release to the atmosphere than from comparable tritium source terms to water pathways. However, the water pathways assessment is clearly site-specific, and the overall aqueous dose will be dependent on downstream receptor populations and uses of the river.

  15. Effect of hypoiodous acid volatility on the iodine source term in reactor accidents

    Energy Technology Data Exchange (ETDEWEB)

    Routamo, T. [Imatran Voima Oy, Vantaa (Finland)

    1996-12-01

    A FORTRAN code ACT WATCH has been developed to establish an improved understanding of essential radionuclide behaviour mechanisms, especially related to iodine chemistry, in reactor accidents. The accident scenarios calculated in this paper are based on the Loss of Coolant accident at the Loviisa Nuclear Power Plant. The effect of different airborne species, especially HIO, on the iodine source term has been studied. The main cause of the high HIO release in the system modelled is the increase of I{sub 2} hydrolysis rate along with the temperature increase, which accelerates HIO production. Due to the high radiation level near the reactor core, I{sub 2} is produced from I{sup -}very rapidly. High temperature in the reactor coolant causes I{sub 2} to be transformed into HIO and through the boiling of the coolant volatile I{sub 2} and HIO are transferred efficiently into the gas phase. High filtration efficiency for particulate iodine causes I{sup -} release to be much lower than those of I{sub 2} and HIO. (author) 15 figs., 1 tab., refs.

  16. THE AVERAGE ANNUAL EFFECTIVE DOSES FOR THE POPULATION IN THE SETTLEMENTS OF THE RUSSIAN FEDERATION ATTRIBUTED TO ZONES OF RADIOACTIVE CONTAMINATION DUE TO THE CHERNOBYL ACCIDENT (FOR ZONATION PURPOSES, 2014

    Directory of Open Access Journals (Sweden)

    G. Ja. Bruk

    2015-01-01

    Full Text Available The Chernobyl accident in 1986 is one of the most large-scale radiation accidents in the world. It led to radioactive contamination of large areas in the European part of the Russian Federation and at the neighboring countries. Now, there are more than 4000 settlements with the total population of 1.5 million in the radioactively contaminated areas of the Russian Federation. The Bryansk region is the most intensely contaminated region. For example, the Krasnogorskiy district still has settlements with the level of soil contamination by cesium-137 exceeding 40 Cu/km2. The regions of Tula, Kaluga and Orel are also significantly affected. In addition to these four regions, there are 10 more regions with the radioactively contaminated settlements. After the Chernobyl accident, the affected areas were divided into zones of radioactive contamination. The attribution of the settlements to a particular zone is determined by the level of soil contamination with 137Cs and by a value of the average annual effective dose that could be formed in the absence of: 1 active measures for radiation protection, and 2 self-limitation in consumption of the local food products. The main regulatory document on this issue is the Federal law № 1244-1 (dated May, 15,1991 «On the social protection of the citizens who have been exposed to radiation as a result of the accident at the Chernobyl nuclear power plant». The law extends to the territories, where, since 1991: – The average annual effective dose for the population exceeds 1 mSv (the value of effective dose that could be formed in the absence of active radiation protection measures and self-limitation in consumption of the local food products; – Soil surface contamination with cesium-137 exceeds 1 Cu/km2. The paper presents results of calculations of the average effective doses in 2014. The purpose was to use the dose values (SGED90 in zonation of contaminated territories. Therefore, the

  17. Accidents in nuclear ships

    Energy Technology Data Exchange (ETDEWEB)

    Oelgaard, P.L. [Risoe National Lab., Roskilde (Denmark)]|[Technical Univ. of Denmark, Lyngby (Denmark)

    1996-12-01

    This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10{sup -3} per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au).

  18. Radioactive contamination of food, sampled in regions of the USSR affected by the Chernobyl accident, and of radioactive exposure in these regions

    NARCIS (Netherlands)

    Ruig, de W.G.; Struijs, van der T.D.B.

    1991-01-01

    From 21.10.1990 to 01.11.1990 a Netherlands humanitarian fact finding mission on aid to people affected by the Chernobyl disaster visited the USSR. The Netherlands Government reacted positively to a request from the USSR for such aid and the aim of the mission was to gather facts for a useful aid pr

  19. Chernobyl Accident Fatalities and Causes

    Science.gov (United States)

    1990-06-01

    died shortly after hospital admission from symptorns of acute radiation sickness, CVA must have been the Kiev fatality on suffered a cerebrovascular ... cerebrovascular acci- unfavorable prognosis IState Committee dent victim with anl estimated close of 3 G\\. 19861. the four bone marrow transplant...ber 1987. Aledical Handling of Skin Lesions Folloti- ing High Level Accidental Irradiation, UNSCEAR (United Nations Scientific Institute Curie, Paris

  20. Chemistry aspects of the source term formation for a severe accident in a CANDU type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Constantin, A.; Constantin, M. [Institute for Nuclear Research, Pitesti (Romania)

    2013-07-15

    The progression of a severe accident in a CANDU type reactor is slow because the core is surrounded by a large quantity of heavy and light water which acts as a heat sink to remove the decay heat. Therefore, the source term formation is a complex and long process involving fission products transport and releasing in the fuel matrix, thermal hydraulics of the transport fluid in the primary heat system and containment, deposition and transport of fission products, chemistry including the interaction with the dousing system, structural materials and paints, etc. The source term is strongly dependent on initial conditions and accident type. The paper presents chemistry aspects for a severe accident in a CANDU type reactor, in terms of the retention in the primary heat system. After releasing from the fuel elements, the fission products suffer a multitude of phenomena before they are partly transferred into the containment region. The most important species involved in the deposition were identified. At the same time, the influence of the break position in the transfer fractions from the primary heat system to the containment was investigated. (orig.)

  1. Guide for licensing evaluations using CRAC2: A computer program for calculating reactor accident consequences

    Energy Technology Data Exchange (ETDEWEB)

    White, J.E.; Roussin, R.W.; Gilpin, H.

    1988-12-01

    A version of the CRAC2 computer code applicable for use in analyses of consequences and risks of reactor accidents in case work for environmental statements has been implemented for use on the Nuclear Regulatory Commission Data General MV/8000 computer system. Input preparation is facilitated through the use of an interactive computer program which operates on an IBM personal computer. The resulting CRAC2 input deck is transmitted to the MV/8000 by using an error-free file transfer mechanism. To facilitate the use of CRAC2 at NRC, relevant background material on input requirements and model descriptions has been extracted from four reports - ''Calculations of Reactor Accident Consequences,'' Version 2, NUREG/CR-2326 (SAND81-1994) and ''CRAC2 Model Descriptions,'' NUREG/CR-2552 (SAND82-0342), ''CRAC Calculations for Accident Sections of Environmental Statements, '' NUREG/CR-2901 (SAND82-1693), and ''Sensitivity and Uncertainty Studies of the CRAC2 Computer Code,'' NUREG/CR-4038 (ORNL-6114). When this background information is combined with instructions on the input processor, this report provides a self-contained guide for preparing CRAC2 input data with a specific orientation toward applications on the MV/8000. 8 refs., 11 figs., 10 tabs.

  2. Chernobyl Studies Project - working group 7.0 environmental transport and health effects. Progress report, October 1993--January 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, S.M. [ed.

    1994-03-01

    The DOE-funded Chernobyl Studies Project was begun as part of a cooperative agreement between the US and the former USSR, (quote) To develop jointly methods to project rapidly the health effects of any future reactor accident (quote). Most of the initial tasks for this project are completed or near completion. The focus has now turned primarily to the issue of health effects from the Chernobyl accident. Currently, we are extensively engaged in case-control and cohort studies of thyroid diseases among Belarussian children and in the Ukraine. A major part of the effort is providing methods and applications of dose reconstruction and providing support and equipment for the medical teams. This document contains reports on progress in the following task areas: Management; External Dose; Hydrological Transport; Chromosome Painting Dosimetry; Stochastic Effects; Thyroid Studies; and Leukemia Studies.

  3. Reporting on Radiation: A Content Analysis of Chernobyl Coverage.

    Science.gov (United States)

    Friedman, Sharon M.; And Others

    1987-01-01

    Evaluates how well the media guided readers and viewers through the Chernobyl disaster. Concludes that the press and television did not provide enough radiation and risk information in their coverage of the Chernobyl accident, but what was provided was appropriate, even-handed, and conservative. (NKA)

  4. Backup and Ultimate Heat Sinks in CANDU Reactors For Prolonged SBO Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Nitheanandan, T.; Brown, M. J. [Atomic Energy of Canada Limited, Ontario (Canada)

    2013-10-15

    In a pressurized heavy water reactor, following loss of the primary coolant, severe core damage would begin with the depletion of the liquid moderator, exposing the top row of internally-voided fuel channels to steam cooling conditions on the inside and outside. The uncovered fuel channels would heat up, deform and disassemble into core debris. Large inventories of water passively reduce the rate of progression of the accident, prolonging the time for complete loss of engineered heat sinks. The efficacy of available backup and ultimate heat sinks, available in a CANDU 6 reactor, in mitigating the consequences of a prolonged station blackout scenario was analysed using the MAAP4-CANDU code. The analysis indicated that the steam generator secondary side water inventory is the most effective heat sink during the accident. Additional heat sinks such as the primary coolant, moderator, calandria vault water and end shield water are also able to remove decay heat; however, a gradually increasing mismatch between heat generation and heat removal occurs over the course of the postulated event. This mismatch is equivalent to an additional water inventory estimated to be 350,000 kg at the time of calandria vessel failure. In the Enhanced CANDU 6 reactor ∼2,040,000 kg of water in the reserve water tank is available for prolonged emergencies requiring heat sinks.

  5. Design considerations for post accident monitoring system of a research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Gwi Sook; Park, Je Yun; Kim, Young Ki [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    The Post Accident Monitoring System (PAMS) provides primary information for operators to assess the plant conditions and perform their role in bringing the plant to a safe condition during an accident. The PAMS of NPP (Nuclear Power Plant) in KOREA provides the continuous display of the PAM category 1 parameters specified in R.G 1.97, Rev. 03. Recently the PAMS of NPP has been designed according to R.G 1.97, Rev. 04. There is no PAMS at the HANARO in KOREA, but recently RRs (Research Reactors) around the world are going to have PAMS for various multi purposes. We should determine the design considerations for PAMS in a Korean RR based on the design state analysis. Thus, this paper proposes strategies on the design considerations for the PAMS of a Korean RR.

  6. Assessment of uncertainties in early off-site consequences from nuclear reactor accidents

    Energy Technology Data Exchange (ETDEWEB)

    Madni, I.K.; Cazzoli, E.G. (Brookhaven National Lab., Dept. of Nuclear Energy, Upton, NY (US)); Khatib-Rahbar, M. (Energy Research, Inc., Rockville, MD (US))

    1990-04-01

    A simplified approach has been developed to calculate uncertainties in early off-site consequences from nuclear reactor accidents. The consequence model (SMART) is based on a solution procedure that uses simplified meteorology and involves direct analytic integration of air concentration equations over time and position. This is different from the discretization approach currently used in the CRAC2 and MACCS codes. The SMART code is fast running, thereby providing a valuable tool for sensitivity and uncertainty studies. The code was benchmarked against both MACCS version 1.4 and CRAC2. Results of benchmarketing and detailed sensitivity and uncertainty analyses using SMART are presented.

  7. Ferritic Alloys as Accident Tolerant Fuel Cladding Material for Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rebak, Raul B. [General Electric Global Research, Schnectady, NY (United States)

    2014-12-30

    The objective of the GE project is to demonstrate that advanced steels such as iron-chromium-aluminum (FeCrAl) alloys could be used as accident tolerant fuel cladding material in commercial light water reactors. The GE project does not include fuel development. Current findings support the concept that a FeCrAl alloy could be used for the cladding of commercial nuclear fuel. The use of this alloy will benefit the public since it is going to make the power generating light water reactors safer. In the Phase 1A of this cost shared project, GE (GRC + GNF) teamed with the University of Michigan, Los Alamos National Laboratory, Brookhaven National Laboratory, Idaho National Laboratory, and Oak Ridge National Laboratory to study the environmental and mechanical behavior of more than eight candidate cladding materials both under normal operation conditions of commercial nuclear reactors and under accident conditions in superheated steam (loss of coolant condition). The main findings are as follows: (1) Under normal operation conditions the candidate alloys (e.g. APMT, Alloy 33) showed excellent resistance to general corrosion, shadow corrosion and to environmentally assisted cracking. APMT also showed resistance to proton irradiation up to 5 dpa. (2) Under accident conditions the selected candidate materials showed several orders of magnitude improvement in the reaction with superheated steam as compared with the current zirconium based alloys. (3) Tube fabrication feasibility studies of FeCrAl alloys are underway. The aim is to obtain a wall thickness that is below 400 µm. (4) A strategy is outlined for the regulatory path approval and for the insertion of a lead fuel assembly in a commercial reactor by 2022. (5) The GE team worked closely with INL to have four rodlets tested in the ATR. GE provided the raw stock for the alloys, the fuel for the rodlets and the cost for fabrication/welding of the rodlets. INL fabricated the rodlets and the caps and welded them to

  8. Analysis of a small break loss-of-coolant accident of pressurized water reactor by APROS

    Energy Technology Data Exchange (ETDEWEB)

    Al-Falahi, A. [Helsinki Univ. of Technology, Espoo (Finland); Haennine, M. [VTT Energy, Espoo (Finland); Porkholm, K. [IVO International, Ltd., Vantaa (Finland)

    1995-09-01

    The purpose of this paper is to study the capability of APROS (Advanced PROcess Simulator) code to simulate the real plant thermal-hydraulic transient of a Small Break Loss-Of-Coolant Accident (SBLOCA) of Loss-Of-Fluid Test (LOFT) facility. The LOFT is a scaled model of a Pressurized Water Reactor (PWR). This work is a part of a larger validation of the APROS thermal-hydraulic models. The results of SBLOCA transient calculated by APROS showed a reasonable agreement with the measured data.

  9. Ferritic Alloys as Accident Tolerant Fuel Cladding Material for Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rebak, Raul B. [General Electric Global Research, Schnectady, NY (United States)

    2014-09-30

    The objective of the GE project is to demonstrate that advanced steels such as iron-chromium-aluminum (FeCrAl) alloys could be used as accident tolerant fuel cladding material in commercial light water reactors. The GE project does not include fuel development. Current findings support the concept that a FeCrAl alloy could be used for the cladding of commercial nuclear fuel. The use of this alloy will benefit the public since it is going to make the power generating light water reactors safer. In the Phase 1A of this cost shared project, GE (GRC + GNF) teamed with the University of Michigan, Los Alamos National Laboratory, Brookhaven National Laboratory, Idaho National Laboratory, and Oak Ridge National Laboratory to study the environmental and mechanical behavior of more than eight candidate cladding materials both under normal operation conditions of commercial nuclear reactors and under accident conditions in superheated steam (loss of coolant condition). The main findings are as follows: (1) Under normal operation conditions the candidate alloys (e.g. APMT, Alloy 33) showed excellent resistance to general corrosion, shadow corrosion and to environmentally assisted cracking. APMT also showed resistance to proton irradiation up to 5 dpa. (2) Under accident conditions the selected candidate materials showed several orders of magnitude improvement in the reaction with superheated steam as compared with the current zirconium based alloys. (3) Tube fabrication feasibility studies of FeCrAl alloys are underway. The aim is to obtain a wall thickness that is below 400 µm. (4) A strategy is outlined for the regulatory path approval and for the insertion of a lead fuel assembly in a commercial reactor by 2022. (5) The GE team worked closely with INL to have four rodlets tested in the ATR. GE provided the raw stock for the alloys, the fuel for the rodlets and the cost for fabrication/welding of the rodlets. INL fabricated the rodlets and the caps and welded them to

  10. Analysis of environmental contamination and human health effects in the southeastern of Belorussia 13 years after the nuclear accident of Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Fueller, J.; Schweitzer, S. [Friedrich-Schiller-University Jena (Germany); Trojanov, M.W. [District Hospital Krasnopolje, Krasnopolje (Belarus)

    2000-05-01

    Associated with the humanitarian aid of the Chernobyl association and the University of Jena for the last 6 years simultaneous analysis of the radioactive contamination and the health situation is performed in the white-russian district of Krasnopolje (200 km north of the reactor, 23.000 inhabitants, 30% of the population evacuated since 1988). The retrospective analysis of incidences of malignant and non-malignant diseases is based on the annual epidemiologic reports of the district physician, comprising data from the past 13 years with a cutoff data of December 31, 1998. The level of contamination of the soil with Cesium 137 measures 1-5 Ci/km{sup 2} in 14% of the territory, 5-15 Ci/km{sup 2} in 50%, 15-40 Ci/km{sup 2} in 25% and >40 Ci/km{sup 2} in 11% (evacuated zone). The gamma-radiation dose rate in still inhabited areas fluctuates from 0,2 to 1,0 micro-Sv/h (normal values: 0,1-0,2 micro-Sv/h). In areas which have been evacuated and closed for agricultural use, levels exceeding 9 micro-Sv/h have been recorded. As expected comparing 1996 to 1998, no decrease of the radiation dose rate in corresponding places of measurement was seen. The existing dosimetry of food which does not fully cover the area shows only slight exceedings of the limits for the basic food supplied by the government controlled trade. With mushrooms, game and berries, peak levels up to 200 times of the Bq-levels per kg were measured. The annual rate of newly diagnosed malignant diseases was relatively constant until 1992 with 23/10.000, but did increase to 43/10.000 in 1993, followed by a decrease to 27/10.000 in 1997 and a increase to 35/10.000 in 1998. Pediatric thyroid carcinoma (n=9) have been observed since 1992. A tendency of growing incidence without significance was seen with tumors of the lungs, the urogenital and the colorectal tract, but barely with leucemia and malignant lymphomas. A significant increase in the incidences of endocrine disorders (hypothyroidism, autonomic adenoma

  11. Chernobyl - 30 years thereafter. Has radiation protection in Switzerland been improved for the handling of emergency situations and the long-term consequences?; Tschernobyl. 30 Jahre danach. Hat sich der Strahlenschutz in der Schweiz zur Bewaeltigung einer Notfallsituation und deren langfristiger Konsequenzen verbessert?

    Energy Technology Data Exchange (ETDEWEB)

    Murith, Christophe [Bundesamt fuer Gesundheit (BAG), Bern (Switzerland). Abt. Strahlenschutz

    2016-05-01

    30 years ago the Chernobyl reactor accident has surprised the whole world. It was shown that severe nuclear accidents contaminating large areas for a long time are possible. At this time each state was overstrained and unable to cope with the situation. Switzerland was oscillating between the French disregard and the German psychosis resulting in chaotic communication increased by incoherency and missing consultation with the neighboring countries.

  12. VICTORIA: A mechanistic model of radionuclide behavior in the reactor coolant system under severe accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Heames, T.J. (Science Applications International Corp., Albuquerque, NM (USA)); Williams, D.A.; Johns, N.A.; Chown, N.M. (UKAEA Atomic Energy Establishment, Winfrith (UK)); Bixler, N.E.; Grimley, A.J. (Sandia National Labs., Albuquerque, NM (USA)); Wheatley, C.J. (UKAEA Safety and Reliability Directorate, Culcheth (UK))

    1990-10-01

    This document provides a description of a model of the radionuclide behavior in the reactor coolant system (RCS) of a light water reactor during a severe accident. This document serves as the user's manual for the computer code called VICTORIA, based upon the model. The VICTORIA code predicts fission product release from the fuel, chemical reactions between fission products and structural materials, vapor and aerosol behavior, and fission product decay heating. This document provides a detailed description of each part of the implementation of the model into VICTORIA, the numerical algorithms used, and the correlations and thermochemical data necessary for determining a solution. A description of the code structure, input and output, and a sample problem are provided. The VICTORIA code was developed upon a CRAY-XMP at Sandia National Laboratories in the USA and a CRAY-2 and various SUN workstations at the Winfrith Technology Centre in England. 60 refs.

  13. Review of core disruptive accident analysis for liquid-metal cooled fast reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y. C.; Na, B. C.; Hahn, D. H

    1997-04-01

    Analysis methodologies of core disruptive accidents (CDAs) are reviewed. The role of CDAS in the overall safety evaluation of fast reactors has not always been well defined nor universally agreed upon. However, they have become a traditional issue in LMR safety, design, and licensing. The study is for the understanding of fast reactor behavior under CDA conditions to establish the consequences of such conditions and to provide a basis for evaluating consequence limiting design features for the KALIMER developments. The methods used to analyze CDAs from initiating event to complete core disruption are described. Two examples of CDA analyses for CRBRP and ALMR are given and R and D needed for better understanding of CDA phenomena are proposed. (author). 10 refs., 2 tabs., 3 figs

  14. International measures for supporting the Ukraine in decommissioning Chernobyl nuclear power plant; Internationale Massnahmen zur Unterstuetzung der Ukraine bei der Stilllegung des KKW Tschernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, J.

    2006-07-01

    The destruction of Block 4 of the Ukranian nuclear power plant in Chernobyl on 26 April 1986 was the largest and most momentous accident in the civil use of nuclear energy. Its far-reaching and lasting ecological, heath-related and economic effects confronted the then Soviet and later the Ukraine with grave problems. Particularly after the dissolution of the Eastern Bloc and the emergence of information about the safety shortcomings of RBMK-type (Chernobyl-type) reactors the Western states pressed for the decommissioning of these reactors. At the G7 summit in Naples in 1994 the Ukraine was offered an action plan of support if it were willing to close down Chernobyl nuclear power plant. This initiative led to the signing on 20 December 1995 of a Memorandum of Understanding on the Closure of Chernobyl Nuclear Power Plant between the G7 states, the European Commission and the Ukraine. It contained an assurance by President Kuchma that Chernobyl nuclear power plant would be closed by the year 2000.

  15. Radiological protection issues arising during and after the Fukushima nuclear reactor accident.

    Science.gov (United States)

    González, Abel J; Akashi, Makoto; Boice, John D; Chino, Masamichi; Homma, Toshimitsu; Ishigure, Nobuhito; Kai, Michiaki; Kusumi, Shizuyo; Lee, Jai-Ki; Menzel, Hans-Georg; Niwa, Ohtsura; Sakai, Kazuo; Weiss, Wolfgang; Yamashita, Shunichi; Yonekura, Yoshiharu

    2013-09-01

    Following the Fukushima accident, the International Commission on Radiological Protection (ICRP) convened a task group to compile lessons learned from the nuclear reactor accident at the Fukushima Daiichi nuclear power plant in Japan, with respect to the ICRP system of radiological protection. In this memorandum the members of the task group express their personal views on issues arising during and after the accident, without explicit endorsement of or approval by the ICRP. While the affected people were largely protected against radiation exposure and no one incurred a lethal dose of radiation (or a dose sufficiently large to cause radiation sickness), many radiological protection questions were raised. The following issues were identified: inferring radiation risks (and the misunderstanding of nominal risk coefficients); attributing radiation effects from low dose exposures; quantifying radiation exposure; assessing the importance of internal exposures; managing emergency crises; protecting rescuers and volunteers; responding with medical aid; justifying necessary but disruptive protective actions; transiting from an emergency to an existing situation; rehabilitating evacuated areas; restricting individual doses of members of the public; caring for infants and children; categorising public exposures due to an accident; considering pregnant women and their foetuses and embryos; monitoring public protection; dealing with 'contamination' of territories, rubble and residues and consumer products; recognising the importance of psychological consequences; and fostering the sharing of information. Relevant ICRP Recommendations were scrutinised, lessons were collected and suggestions were compiled. It was concluded that the radiological protection community has an ethical duty to learn from the lessons of Fukushima and resolve any identified challenges. Before another large accident occurs, it should be ensured that inter alia: radiation risk coefficients of potential

  16. Radiation protection: an analysis of thyroid blocking. [Effectiveness of KI in reducing radioactive uptake following potential reactor accident

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, D C; Blond, R M

    1980-01-01

    An analysis was performed to provide guidance to policymakers concerning the effectiveness of potassium iodide (KI) as a thyroid blocking agent in potential reactor accident situations, the distance to which (or area within which) it should be distributed, and its relative effectiveness compared to other available protective measures. The analysis was performed using the Reactor Safety Study (WASH-1400) consequence model. Four categories of accidents were addressed: gap activity release accident (GAP), GAP without containment isolation, core melt with a melt-through release, and core melt with an atmospheric release. Cost-benefit ratios (US $/thyroid nodule prevented) are given assuming that no other protective measures are taken. Uncertainties due to health effects parameters, accident probabilities, and costs are assessed. The effects of other potential protective measures, such as evacuation and sheltering, and the impact on children (critical population) are evaluated. Finally, risk-benefit considerations are briefly discussed.

  17. Consequence analysis of core meltdown accidents in liquid metal fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Suk, S.D.; Hahn, D. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2001-07-01

    Core disruptive accidents have been investigated at Korea Atomic Energy Research Institute(KAERI) as part of work to demonstrate the inherent and ultimate safety of the conceptual design of the Korea Advanced Liquid Metal Reactor(KALIMER), a 150 Mw pool-type sodium cooled prototype fast reactor that uses U-Pu-Zr metallic fuel. In this study, a simple method was developed using a modified Bethe-Tait method to simulate the kinetics and hydraulic behavior of a homogeneous spherical core over the period of the super-prompt critical power excursion induced by the ramp reactivity insertion. Calculations of energy release during excursions in the sodium-voided core of the KALIMER were subsequently performed using the method for various reactivity insertion rates up to 100 $/s, which has been widely considered to be the upper limit of ramp rates due to fuel compaction. Benchmark calculations were made to compare with the results of more detailed analysis for core meltdown energetics of the oxide fuelled fast reactor. A set of parametric studies was also performed to investigate the sensitivity of the results on the various thermodynamics and reactor parameters. (author)

  18. Simulating experimental investigation on the safety of nuclear heating reactor in loss-of-coolant accidents

    Science.gov (United States)

    Xu, Zhanjie

    1996-12-01

    The 5MW low temperature nuclear heating reactor (NHR-5) is a new and advanced type of nuclear reactor developed by Institute of Nuclear Energy Technology (INET) of Tsinghua University of China in 1989. Its main loop is a thermal-hydraulic system with natural circulation. This paper studies the safety of NHR under the condition of loss-of-coolant accidents (LOCAs) by means of simulant experiments. First, the background and necessity of the experiments are presented, then the experimental system, including the thermal-hydraulic system and the data collection system, and similarity criteria are introduced. Up to now, the discharge experiments with the residual heating power (20% rated heating power) have been carried out on the experimental system. The system parameters including circulation flow rate, system pressure, system temperature, void fraction, discharge mass and so on have been recorded and analyzed. Based on the results of the experiments, the conclusions are shown as follos: on the whole, the reactor is safe under the condition of LOCAs, but the thermal vacillations resulting from the vibration of the circulation flow rate are disadvantageous to the internal parts of the reactor core.

  19. Phenomenological and mechanistic modeling of melt-structure-water interactions in a light water reactor severe accident

    Energy Technology Data Exchange (ETDEWEB)

    Bui, V.A

    1998-10-01

    The objective of this work is to address the modeling of the thermal hydrodynamic phenomena and interactions occurring during the progression of reactor severe accidents. Integrated phenomenological models are developed to describe the accident scenarios, which consist of many processes, while mechanistic modeling, including direct numerical simulation, is carried out to describe separate effects and selected physical phenomena of particular importance 88 refs, 54 figs, 7 tabs

  20. Chernobyl. Answers to your questions; Tchernobyl. Des reponses a vos questions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Fifteen years after the Chernobyl accident, this document takes stock on the existing information and enhance the elements which can be set with certainty. The accident is recalled and the environmental and biological effects are presented. (A.L.B.)

  1. Radionuclides release possibility analysis of MSR at various accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Choong Wie; Kim, Hee Reyoung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    There are some accidents which go beyond our expectation such as Fukushima Daiichi nuclear disaster and amounts of radionuclides release to environment, so more effort and research are conducted to prevent it. MSR (Molten Salt Reactor) is one of GEN-IV reactor types, and its coolant and fuel are mixtures of molten salt. MSR has a schematic like figure 1 and it has different features with the solid fuel reactor, but most important and interesting feature of MSR is its many safety systems. For example, MSR has a large negative void coefficient. Even though power increases, the reactor slows down soon. Radionuclides release possibility of MSR was analyzed at various accident conditions including Chernobyl and Fukushima ones. The MSR was understood to prevent the severe accident by the negative reactivity coefficient and the absence of explosive material such as water at the Chernobyl disaster condition. It was expected to contain fuel salts in the reactor building and not to release radionuclides into environment even if the primary system could be ruptured or broken and fuel salts would be leaked at the Fukushima Daiichi nuclear disaster condition of earthquake and tsunami. The MSR, which would not lead to the severe accident and therefore prevents the fuel release to the environment at many expected scenarios, was thought to have priority in the aspect of accidents. A quantitative analysis and a further research are needed to evaluate the possibility of radionuclide release to the environment at the various accident conditions based on the simple comparison of the safety feature between MSR and solid fuel reactor.

  2. Ten years of work in Cuban Program to children from areas affected of Chernobyl accidents; Diez anos de trabajo en el programa cubano com ninos de territorios afectados por el accidente de Chernobil

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Omar [Centro de Proteccion y Higiene de las Radiaciones, La Habana (Cuba)]. E-mail: omar@cprh.edu.cu; Medina J, Julio [Hospital Pediatrico Tarara, Ciudad Habana (Cuba)

    2001-07-01

    In April of 2000 the Cuban program for specialised medical attention to children from areas affected by the radioactive contamination from the Chernobyl accident completed 10 years of work. In the program had been assisted more than 18 000 children and adults, among them 50 Brazilians related with the Goiania accident. A group of medical procedures and dosimetric, biomedical and psychological investigations have been carried out in the program. The main significant medical attention activities are the treatment of haematological disorders, among them, 120 leukaemia, the realisation of bone marrow transplants and the treatment of endocrinological and neoplasic illnesses. The dosimetric studies has allowed to create a database that accumulates information about internal contamination for 137Cs, internal, external, and total doses, of 7000 children. The analysis of the behaviour of all the medical information that is generated in the program in function of the contamination of the land and of the internal contamination of the children is also performed. The program has accumulated an experience of interest for physicians, psychologists and radiological emergencies experts.(author)

  3. Development, control and counter-measures regarding radioactive caesium in Swedish reindeer after the Chernobyl accident; Utveckling, oevervakning och aatgaerder naer det gaeller radioaktivt cesium i renar efter Tjernobylolyckan

    Energy Technology Data Exchange (ETDEWEB)

    Aahman, Birgitta [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Reindeer Husbandry Unit

    2005-10-01

    Since the Chernobyl accident in 1986, monitoring of {sup 137}Cs in reindeer has been made at slaughter, by measuring muscle samples or by direct monitoring of gamma radiation on reindeer carcasses. Carcasses above the accepted limit have been discarded. Many carcasses were discarded during the first years, but now the number is only some per cent of the total slaughter. The radiocaesium intake in reindeer varies with season, which is reflected in the levels in reindeer, which are low in summer and high in winter. The levels of {sup 137}Cs have declined from 1986 to 2004 with an average effective half-life of 5.3 years. The decline was faster during the first years than during later years. Presently, 16 out of totally 51 reindeer herding districts in Sweden are included in the control of {sup 137}Cs in reindeer. Control is often necessary only in defined areas or at certain periods of the year. Monitoring of {sup 137}Cs in live reindeer is made in addition to the monitoring at slaughter. Counter-measures have been applied in areas where many reindeer are above the accepted limit for {sup 137}Cs. Change of slaughter time and feeding are the most used counter-measures. The reindeer owners are compensated economically from the state for costs related to these counter-measures. The need for measures, and thereby the costs, have decreased with time. In the southern parts of the county of Vaesterbotten and in the northernmost part of Jaemtland, where the Chernobyl fallout was the highest, it will probably still take at least ten to twenty years until measures and control are no longer needed.

  4. Prediction of the reactor vessel water level using fuzzy neural networks in severe accident circumstance of NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soon Ho; Kim, Dae Seop; Kim, Jae Hwan; Na, Man Gyun [Dept. of Nuclear Engineering, Chosun University, Gwangju (Korea, Republic of)

    2014-06-15

    Safety-related parameters are very important for confirming the status of a nuclear power plant. In particular, the reactor vessel water level has a direct impact on the safety fortress by confirming reactor core cooling. In this study, the reactor vessel water level under the condition of a severe accident, where the water level could not be measured, was predicted using a fuzzy neural network (FNN). The prediction model was developed using training data, and validated using independent test data. The data was generated from simulations of the optimized power reactor 1000 (OPR1000) using MAAP4 code. The informative data for training the FNN model was selected using the subtractive clustering method. The prediction performance of the reactor vessel water level was quite satisfactory, but a few large errors were occasionally observed. To check the effect of instrument errors, the prediction model was verified using data containing artificially added errors. The developed FNN model was sufficiently accurate to be used to predict the reactor vessel water level in severe accident situations where the integrity of the reactor vessel water level sensor is compromised. Furthermore, if the developed FNN model can be optimized using a variety of data, it should be possible to predict the reactor vessel water level precisely.

  5. Reactor physics modelling of accident tolerant fuel for LWRs using ANSWERS codes

    Directory of Open Access Journals (Sweden)

    Lindley Benjamin A.

    2016-01-01

    Full Text Available The majority of nuclear reactors operating in the world today and similarly the majority of near-term new build reactors will be LWRs. These currently accommodate traditional Zr clad UO2/PuO2 fuel designs which have an excellent performance record for normal operation. However, the events at Fukushima culminated in significant hydrogen production and hydrogen explosions, resulting from high temperature Zr/steam interaction following core uncovering for an extended period. These events have resulted in increased emphasis towards developing more accident tolerant fuels (ATFs-clad systems, particularly for current and near-term build LWRs. R&D programmes are underway in the US and elsewhere to develop ATFs and the UK is engaging in these international programmes. Candidate advanced fuel materials include uranium nitride (UN and uranium silicide (U3Si2. Candidate cladding materials include advanced stainless steel (FeCrAl and silicon carbide. The UK has a long history in industrial fuel manufacture and fabrication for a wide range of reactor systems including LWRs. This is supported by a national infrastructure to perform experimental and theoretical R&D in fuel performance, fuel transient behaviour and reactor physics. In this paper, an analysis of the Integral Inherently Safe LWR design (I2S-LWR, a reactor concept developed by an international collaboration led by the Georgia Institute of Technology, within a US DOE Nuclear Energy University Program (NEUP Integrated Research Project (IRP is considered. The analysis is performed using the ANSWERS reactor physics code WIMS and the EDF Energy core simulator PANTHER by researchers at the University of Cambridge. The I2S-LWR is an advanced 2850 MWt integral PWR with inherent safety features. In order to enhance the safety features, the baseline fuel and cladding materials that were chosen for the I2S-LWR design are U3Si2 and advanced stainless steel respectively. In addition, the I2S-LWR design

  6. [Comparative analysis of semiotic shifts, established by LCS of blood plasma from random samples of studied subjects from the zone of the Chernobyl accident, "Ural Radiation Trace", and collaborators from St. Petersburg Institute of Nuclear Physics of the Russian Academy of Sciences].

    Science.gov (United States)

    Ternovoĭ, K S; Selezneva, T N; Akleev, A V; Pashkov, I A; Noskin, L A; Klopov, N V; Noskin, V A; Starodub, N F

    1998-01-01

    Using the developed "semiotic" classifier of laser correlation spectra of blood plasma the authors have carried out the verification of organism states of patients from the zone of Chernobyl accident, "Ural radiation trace" and collaborators from Sanct-Petersbourg Institute of Nuclear Physics. An analysis of results obtained using accidental selections which differed as to the character of radiation injury evidences for high informativeness of "semiotic" classifier of laser correlation spectra of blood plasma.

  7. Evaluation of an accident management strategy of emergency water injection using fire engines in a typical pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soo Yong; Ahn, Kwang Il [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Following the Fukushima accident, a special safety inspection was conducted in Korea. The inspection results show that Korean nuclear power plants have no imminent risk for expected maximum potential earthquake or coastal flooding. However long- and short-term safety improvements do need to be implemented. One of the measures to increase the mitigation capability during a prolonged station blackout (SBO) accident is installing injection flow paths to provide emergency cooling water of external sources using fire engines to the steam generators or reactor cooling systems. This paper illustrates an evaluation of the effectiveness of external cooling water injection strategies using fire trucks during a potential extended SBO accident in a 1,000 MWe pressurized water reactor. With regard to the effectiveness of external cooling water injection strategies using fire engines, the strategies are judged to be very feasible for a long-term SBO, but are not likely to be effective for a short-term SBO.

  8. Probability and consequences of severe reactor accidents. 60th year atw

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Norman Carl [Massachusetts Institute of Technology (MIT), Cambridge, MA (United States). Dept. of Nuclear Engineering

    2015-06-15

    The study carried out on behalf of former USAEC (United States Atomic Energy Commission) led by Prof. Rasmussen and published in reworked form as WASH 1400 by the USNRC (United States Nuclear Regulatory Commission) in 1975, assessed in 3,300 pages the risks that can be deducted from severe accidents in nuclear power plants. The results, often quoted and criticised, were so far the most conclusive statements to this question. In his lecture at the reactor meeting in 1976, Prof. Rasmussen tried to trace back the conclusion of the results to the question: Is the use of larger nuclear power plants, in accordance to experiences and calculations so far, acceptable? His risk assessment, related to American power plants and cites, on behalf of the BMI is currently evaluated by the IRS together with the LRA on specific occurrences within the Federal Republic of Germany.

  9. The Chernobyl catastrophe: Consequences on human health

    Energy Technology Data Exchange (ETDEWEB)

    Yablokov, A.; Labunska, I.; Blokov, I.; Santillo, D.; Johnston, P.; Stringer, R.; Sadownichik, T. (eds.); Antipkin, Yu.G. [Institute of Paediatrics, Obstetrics and Gynaecology, Academy of Medical Sciences, Kiev (Ukraine); Arabskaya, L.P. [Institute of Paediatrics, Obstetrics and Gynaecology, Academy of Medical Sciences, Kiev (Ukraine); Bazyka, D.A. [Research Centre for Radiation Medicine, Academy of Medical Sciences, Kiev (Ukraine)] (and others)

    2006-04-15

    This new Greenpeace report estimates that the full consequences of the Chernobyl disaster could top a quarter of a million cancers cases and nearly 100,000 fatal cancers. It reports that the report involved 52 respected scientists and includes information never before published in English. It challenges the International Atomic Energy Agency Chernobyl Forum report, which predicted 4,000 additional deaths attributable to the accident as a gross simplification of the real breadth of human suffering. Their data, based on Belarus national cancer statistics, predicts approximately 270,000 cancers and 93,000 fatal cancer cases caused by Chernobyl. The report also concludes that on the basis of demographic data, during the last 15 years, 60,000 people have additionally died in Russia because of the Chernobyl accident, and estimates of the total death toll for the Ukraine and Belarus could reach another 140,000. The report also looks into the ongoing health impacts of Chernobyl and concludes that radiation from the disaster has had a devastating effect on survivors; damaging immune and endocrine systems, leading to accelerated ageing, cardiovascular and blood illnesses, psychological illnesses, chromosomal aberrations and an increase in foetal deformations.

  10. Study on corium behavior in the reactor cavity during severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soo Yong; Song, Y. M.; Kim, D. H. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-03-01

    The report contains following four results of studies on molten corium-concrete interaction, which has been recognized as important aspects of severe reactor accident; 1. MELCOR code modification has been performed for heat transfer model between ex-vessel molten corium and overlying water pool. The existing model do not consider debris particulation and water penetration in the ex-vessel debris cooling. The new model employs dryout heat flux in determining the heat removal from a debris bed by water penetration. 2. A parametric model which can evaluate ex-vessel concrete erosions has been developed. The model is expected to evaluate the concrete erosion in a limited error range with only a little effort. The model has been derived by the sensitivity studies using MELCOR and MAAP programs. 3. During the corium-concrete interaction, there is a temperature distribution inside basemat concrete. MELCOR calculates concrete response based on one-dimensional steady-state ablation, with no consideration given to conduction into the concrete or to decomposition in advance of the ablation front. Thus there is a necessity to improve the concrete decomposition model in MELCOR. In this report the transient conduction model and the methodology of implementation into MELCOR were suggested. 4. Major modeling assumptions and limits of MELTSPREAD-1, which is a transient one-dimensional computer code to predict the gravity-driven spreading of molten corium in the reactor cavity under severe accidents, are evaluated via review of general conservation equations and used models. The models being reviewed include heat transfer models at melt lower/upper surfaces, a concrete dryout model, and a shell heatup model. The evaluation results suggest the degree of MELTSPREAD-1 approximation compared with real spreading flow and the strong/weak points or restrictions of the code. 17 refs., 19 figs., 6 tabs. (Author)

  11. Transfer of the Fukushima Daiichi reactor accident-derived radionuclides in forest environments

    Science.gov (United States)

    Kato, Hiroaki; Onda, Yuichi; Kawamori, Ayumi; Hisadome, Keigo

    2013-04-01

    The Fukushima Daiichi nuclear power plant accident resulted in extensive radioactive contamination of the forest environment in Fukushima and the neighboring prefectures. In this study, we analyzed radiocesium concentrations in rainwater, throughfall, stemflow, and litterfall to characterize the transfer of the deposited radiocesium in various forest stands (evergreen conifers and broad-leaved forests), in Tochigi (Cs-137 fallout < 10 kBq/m^2) and Fukushima (Cs-137 fallout = 300-600 kBq/m^2) prefectures. Furthermore, in-situ measurement of radiocesium were conducted to delineate spatio-temporal variability of radiocesium in the canopy and forest floor. The result of this study demonstrated that a large proportion of radionuclides which deposited on forest were initially trapped by canopies, and subsequently transferred to forest floor in association with throughfall, stemflow, and litterfall. In the deciduous broad-leaved forest, the highest radioactivity was found at the forest floor; however, 25-40% of the total deposited radiocesium remained in the canopy of evergreen coniferous forests one year after the reactor accident.

  12. Improvement of Severe Accident Analysis Computer Code and Development of Accident Management Guidance for Heavy Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soo Yong; Kim, Ko Ryu; Kim, Dong Ha; Kim, See Darl; Song, Yong Mann; Choi, Young; Jin, Young Ho

    2005-03-15

    The objective of the project is to develop a generic severe accident management guidance(SAMG) applicable to Korean PHWR and the objective of this 3 year continued phase is to construct a base of the generic SAMG. Another objective is to improve a domestic computer code, ISAAC (Integrated Severe Accident Analysis code for CANDU), which still has many deficiencies to be improved in order to apply for the SAMG development. The scope and contents performed in this Phase-2 are as follows: The characteristics of major design and operation for the domestic Wolsong NPP are analyzed from the severe accident aspects. On the basis, preliminary strategies for SAM of PHWR are selected. The information needed for SAM and the methods to get that information are analyzed. Both the individual strategies applicable for accident mitigation under PHWR severe accident conditions and the technical background for those strategies are developed. A new version of ISAAC 2.0 has been developed after analyzing and modifying the existing models of ISAAC 1.0. The general SAMG applicable for PHWRs confirms severe accident management techniques for emergencies, provides the base technique to develop the plant specific SAMG by utility company and finally contributes to the public safety enhancement as a NPP safety assuring step. The ISAAC code will be used inevitably for the PSA, living PSA, severe accident analysis, SAM program development and operator training in PHWR.

  13. Chernobyl record. The definitive history of the Chernobyl catastrophe

    Energy Technology Data Exchange (ETDEWEB)

    Mould, R.F

    2000-07-01

    The contents of Chernobyl Record have taken 14 years to compile and this period of time was necessary to enable information to be released from Soviet sources, measurements to be made in the environment, for estimation of radiation doses and for follow-up of the health of population groups which had been exposed. This time frame also includes the 10th anniversary conferences and the completion of joint projects of the European Commission, Ukraine, Belarus and the Russian Federation. It has also enabled me to visit the power plant site, Chernobyl town and Pripyat relatively soon after the accident and also some 10 years later: December 1987 and June 1998. Without such visits some of the photographs in this Record could not have been obtained. Information is also contained in these pages of comparisons of various aspects of the Chernobyl accident with data from the Three Mile Island accident in the USA in 1979, the Hiroshima and Nagasaki atomic bombs, the highly contaminated Techa river area in the Urals in Russia and the accident in Tokaimura, Japan in 1999. The first two chapters are introductory in that they describe terminology which is necessary for an understanding of the remaining chapters. Chapters 3-6 describes the early events: including those leading up to the explosion and then what followed in the immediate aftermath. Chapters 7-8 describe the Sarcophagus and the past and future of nuclear power for electricity generation, including the future of the Chernobyl power station. Chapters 9-11 consider the radiation doses received by various populations, including liquidators, evacuees and those living on contaminated territories: and the contamination of milk by {sup 131}I, and the contamination of other parts of the food chain by {sup 137}Cs. Chapters 12-14 describe the environmental impact of the accident, as does chapter 11. Chapters 15-18 detail the long-term effects on health, including not only the incidence of cancer, but also of non

  14. Research and development with regard to severe accidents in pressurised water reactors: Summary and outlook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This document reviews the current state of research on severe accidents in France and other countries. It aims to provide an objective vision, and one that's as exhaustive as possible, for this innovative field of research. It will help in identifying R and D requirements and categorising them hierarchically. Obviously, the resulting prioritisation must be completed by a rigorous examination of needs in terms of safety analyses for various risks and physical phenomena, especially in relation to Level 2 Probabilistic Safety Assessments. PSA-2 should be sufficiently advanced so as not to obscure physical phenomena that, if not properly understood, might result in substantial uncertainty. It should be noted that neither the safety analyses nor PSA-2 are presented in this document. This report describes the physical phenomena liable to occur during a severe accident, in the reactor vessel and the containment. It presents accident sequences and methods for limiting impact. The corresponding scenarios are detailed in Chapter 2. Chapter 3 deals with in-vessel accident progression, examining core degradation (3.1), corium behaviour in the lower head (3.2), vessel rupture (3.3) and high-pressure core meltdown (3.4). Chapter 4 focuses on phenomena liable to induce early containment failure, namely direct containment heating (4.1), hydrogen risk (4.2) and steam explosions (4.3). The phenomenon that could lead to a late containment failure, namely molten core-concrete interaction, is discussed in Chapter 5. Chapter 6 focuses on problems related to in-vessel and ex-vessel corium retention and cooling, namely in-vessel retention by flooding the primary circuit or the reactor pit (6.1), cooling of the corium under water during the corium-concrete interaction (6.2), corium spreading (6.3) and ex-vessel core catchers (6.4). Chapter 7 relates to the release and transport of fission products (FP), addressing the themes of in-vessel FP release (7.1) and ex-vessel FP release (7

  15. Steady state and accident analysis of SCOR (simple compact reactor) with the CATHARE code

    Energy Technology Data Exchange (ETDEWEB)

    Marie-Sophie Chenaud; Guy-Marie Gautier [CEA Cadarache- 13108 St Paul Lez Durance (France)

    2005-07-01

    Full text of publication follows: Within the framework of innovative reactors studies, the CEA was led to propose the SCOR design (Simple Compact Reactor). This design is based on a compact 600 MWe PWR and combines most of the advantages of innovative reactors. All main components such as the pressurizer, the canned pumps, the control rod mechanics and the dedicated heat exchangers on the passive residual heat removal system are integrated in the vessel.The only steam generator is located above the vessel in place of the upper head. The reactor operates at much lower primary circuit pressure than standard PWRs (85 bar instead of the usual 155 bar) and the power density is low (70 MW/m{sup 3} instead of 100 MW/m{sup 3} for the present PWRs). The reactivity being controlled by control rods and burnable poisons, there is no soluble boron. The elimination of a serious LOCA (Loss Of Coolant Accident) and the integrated residual heat removal system lead to enhanced safety with simple safety systems. Main features of the SCOR design and functional parameters have been previously reported. This paper focuses on the safety analysis of SCOR. Thermo hydraulic calculations have been run with the CATHARE code. Some calculations were run with the point kinetics module of CATHARE. Several transient simulations have been assessed. They concern a normal reactor trip from full power operation till refueling shutdown and accidental scenarios such as: - Loss of power, - Breaks from 0.02 m to 0.1 m on circuits connected to the vessel, - Steam generator tubes rupture, - Reactivity insertion by cold shock. Results of transient simulations enable us to conclude upon: - the increase of grace periods in comparison with standard PWRs if no safety systems operate besides emergency shutdown, - the expected efficiency of designed safety systems and in particular of the residual heat removal system in passive configuration even when integrated exchanger are dewatered. It will be retained that

  16. [The Fukushima nuclear accident: consequences for Japan and for us].

    Science.gov (United States)

    Grosche, B

    2013-04-01

    The Fukushima accident was the consequence of a preceding 2-fold natural catastrophe: the earth quake of 11 March 2011 and the subsequent tsunami. Due to favourable winds and to evacuation measures the radiation exposure to the general population in Japan as a whole and with some exceptions in the region outside the evacuation zone, too, was low. In this article the attempt is made to give an estimate of health consequences to the public. This is based upon WHO's dose estimates, knowledge of the consequences of the Chernobyl accident, of the atmospheric nuclear bomb testing in Kazakhstan and on the risk of childhood leukaemia after low dose radiation exposure. For Germany, there was no radiation threat due to the accident. Nonetheless, the events in Japan made clear that the rules and standards that were developed for the case of a reactor accident need to be revised.

  17. Analysis of simulation results of damaged nuclear fuel accidents at NPPs with shell-type nuclear reactors

    Directory of Open Access Journals (Sweden)

    Igor L. Kozlov

    2015-03-01

    Full Text Available Lessons from the accident at the Fukushima Daiichi NPP made it necessary to reevaluate and intensificate the work on modeling and analyzing various scenarios of severe accidents with damage to the nuclear fuel in the reactor, containment and spent nuclear fuel storage pool with the expansion of the primary initiating event causes group listing. Further development of computational tools for modeling the explosion prevention criteria as to steam and gas mixtures, considering the specific thermal-hydrodynamic conditions and mechanisms of explosive situations arrival at different stages of a severe accident development, is substantiated. Based on the analysis of the known shell-type nuclear reactors accidents results the explosion safety thermodynamic criteria are presented, the parameters defining the steam and gas explosions conditions are found, the need to perform the further verification and validation of deterministic codes serving to simulate general accident processes behavior as well as phase-to-phase interaction calculated dependencies is established. The main parameters controlling and defining the criteria explosion safety effective regulation areas and their optimization conditions are found.

  18. Chernobyl Studies Project: Working group 7.0, Environmental transport and health effects. Progress report, March--September 1994

    Energy Technology Data Exchange (ETDEWEB)

    Anspaugh, L.R.; Hendrickson, S.M. [eds.

    1994-12-01

    In April 1988, the US and the former-USSR signed a Memorandum of Cooperation (MOC) for Civilian Nuclear Reactor Safety; this MOC was a direct result of the accident at the Chernobyl Nuclear Power Plant Unit 4 and the following efforts by the two countries to implement a joint program to improve the safety of nuclear power plants and to understand the implications of environmental releases. A Joint Coordinating Committee for Civilian Nuclear Reactor Safety (JCCCNRS) was formed to implement the MOC. The JCCCNRS established many working groups; most of these were the responsibility of the Nuclear Regulatory Commission, as far as the US participation was concerned. The lone exception was Working Group 7 on Environmental Transport and Health Effects, for which the US participation was the responsibility of the US Department of Energy (DOE). The purpose of Working Group 7 was succintly stated to be, ``To develop jointly methods to project rapidly the health effects of any future nuclear reactor accident.`` To implement the work DOE then formed two subworking groups: 7.1 to address Environmental Transport and 7.2 to address Health Effects. Thus, the DOE-funded Chernobyl Studies Project began. The majority of the initial tasks for this project are completed or near completion. The focus is now turned to the issue of health effects from the Chernobyl accident. Currently, we are involved in and making progress on the case-control and co-hort studies of thyroid diseases among Belarussian children. Dosimetric aspects are a fundamental part of these studies. We are currently working to implement similar studies in Ukraine. A major part of the effort of these projects is supporting these studies, both by providing methods and applications of dose reconstruction and by providing support and equipment for the medical teams.

  19. Modelling of the transfer of Cs-137 from air to crops, milk, beef and human body following the Chernobyl accident in a location in Central Bohemia. Test of the model PRYMA T1

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, E.; Garcia-Olivares, A.; Suanez, A.; Robles, B.; Simon, I.; Cancio, D.

    1994-07-01

    This work was made in the frame of the research programme on validation od models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. the acronym of this programme is VAMP (Validation of Model Predictions) and is co-ordinated by the International Atomic energy Agency (IAEA) and the Commission of the european Communities (CEC). The scenario was named CB and Was presented by the Multiple Pathway Working group. the scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. the input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and ore, description of the scenario (data about crops, cattle, demography, human diet, etc.). the aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed. (Author) 24 refs.

  20. Sandia National Laboratories results for the 2010 criticality accident dosimetry exercise, at the CALIBAN reactor, CEA Valduc France.

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Dann C.

    2011-09-01

    This document describes the personal nuclear accident dosimeter (PNAD) used by Sandia National Laboratories (SNL) and presents PNAD dosimetry results obtained during the Nuclear Accident Dosimeter Intercomparison Study held 20-23 September, 2010, at CEA Valduc, France. SNL PNADs were exposed in two separate irradiations from the CALIBAN reactor. Biases for reported neutron doses ranged from -15% to +0.4% with an average bias of -7.7%. PNADs were also exposed on the back side of phantoms to assess orientation effects.

  1. Response of an ESBWR to an accident like Fukushima; Respuesta de un reactor ESBWR a un accidente tipo Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Pena G, C. A. [UNAM, Facultad de Ingenieria, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Salazar S, E., E-mail: carlos.pena.guerreo@gmail.com [UNAM, Facultad de Ingenieria, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, 62250 Jiutepec, Morelos (Mexico)

    2014-10-15

    The Fukushima nuclear accident occurred on March 11, 2011 was caused by an earthquake measuring 9.0 on the seismic scale, damaging the nuclear power plant (NPP) containing 6 nuclear reactors of boiling water, some of whom suffered a meltdown due to failure in the cooling systems of these. Electrical wiring was damaged and emergency diesel generators stopped with the arrival of the tsunami, caused by the earthquake. The presence of many critical systems in flood areas provided that a cascade of technological failures occurred, culminating in the complete loss of control over the central and reactors. This had important political consequences and several countries have revised their nuclear programs, considering dangerous and unworkable to the nuclear energy to meet the specific energy needs of each country. However, progress in the design of new reactors raise the possibility of continuing to use nuclear energy for much safer than before. The NPP of Fukushima contained BWR reactors of the first commercial generation designed in the 50. The new passive safety systems raise the idea of simplifying the systems, lowering costs while they are safer systems. New designs meet a these needs in both BWRs and PWRs. In this paper the response of an ESBWR reactor to similar conditions to those suffered by the reactors of Fukushima NPP during the accident is analyzed. In this new reactor of III + generation, the recirculation pumps are removed and emergency cooling systems that can maintain the stable core for several hours without electricity are used. To analyze the responses of this new reactor the simulator with basic principles that IAEA makes available to from Member States was used to better understand and analyze the performance of this type of reactors. (Author)

  2. Estimation of doses received by operators in the 1958 RB reactor accident using the MCNP5 computer code simulation

    Directory of Open Access Journals (Sweden)

    Pešić Milan P.

    2012-01-01

    Full Text Available A numerical simulation of the radiological consequences of the RB reactor reactivity excursion accident, which occurred on October 15, 1958, and an estimation of the total doses received by the operators were run by the MCNP5 computer code. The simulation was carried out under the same assumptions as those used in the 1960 IAEA-organized experimental simulation of the accident: total fission energy of 80 MJ released in the accident and the frozen positions of the operators. The time interval of exposure to high doses received by the operators has been estimated. Data on the RB1/1958 reactor core relevant to the accident are given. A short summary of the accident scenario has been updated. A 3-D model of the reactor room and the RB reactor tank, with all the details of the core, created. For dose determination, 3-D simplified, homogenised, sexless and faceless phantoms, placed inside the reactor room, have been developed. The code was run for a number of neutron histories which have given a dose rate uncertainty of less than 2%. For the determination of radiation spectra escaping the reactor core and radiation interaction in the tissue of the phantoms, the MCNP5 code was run (in the KCODE option and “mode n p e”, with a 55-group neutron spectra, 35-group gamma ray spectra and a 10-group electron spectra. The doses were determined by using the conversion of flux density (obtained by the F4 tally in the phantoms to doses using factors taken from ICRP-74 and from the deposited energy of neutrons and gamma rays (obtained by the F6 tally in the phantoms’ tissue. A rough estimation of the time moment when the odour of ozone was sensed by the operators is estimated for the first time and given in Appendix A.1. Calculated total absorbed and equivalent doses are compared to the previously reported ones and an attempt to understand and explain the reasons for the obtained differences has been made. A Root Cause Analysis of the accident was done and

  3. Safety aspects of fuel behaviour during faults and accidents in pressurised water reactors and in liquid sodium cooled fast breeder reactors

    Energy Technology Data Exchange (ETDEWEB)

    Gittus, J.H. (UKAEA Information Services Branch, London); Matthews, J.R. (UKAEA Harwell Lab. (UK). Theoretical Physics Div.); Potter, P.E. (UKAEA Harwell Lab. (UK). Chemistry Div.)

    1989-07-01

    The good safety record of electrical power generating reactors in the European Community is based on a substantial effort to understand the safety characteristics of the reactors and their fuel. In this paper the present state of knowledge of oxide fuels used in current European reactors is reviewed. The main theme of the paper is the importance of the role of fission products and the chemical state of the fuel on all aspects of fuel behaviour. The paper is split into two parts. The first part deals with those aspects specific to water reactors using UO{sub 2} based fuels. The second part of the paper deals with mixed-oxide fuels and the sodium cooled reactors. In each part the following aspects are described: Chemical constitution of the fuel; fuel performance and failure limits; failed fuel behaviour; fuel behaviour in accidents; and the interactions in degraded cores after hypothetical accidents. Future directions of safety related fuel work in Europe are identified. (orig.).

  4. Chernobyl - 30 years thereafter. Experiences and lessons learned in Austria; 30 Jahre nach Tschernobyl. Erfahrungen und Lehren in Oesterreich

    Energy Technology Data Exchange (ETDEWEB)

    Maringer, Franz Josef [BEV - Bundesamt fuer Eich- und Vermessungswesen, Wien (Austria). Referat fuer ionisierende Strahlung und Radioaktivitaet; Hajek, Michael [Oesterreichischer Verband fuer Strahlenschutz, Wien (Austria). Vienna International Centre; Steger, Ferdinand; Hefner, Alfred

    2016-05-01

    During the severe reactor accident in Chernobyl in 1986 large amounts of radioactive materials have been released to the environment. Unfavorable atmospheric circulation conditions have transported about 2%of the released radioactive matter to Austria. The contribution describes the measures and actions for dose reduction performed in Austria. The measured cs-137 distribution is illustrated (in some areas more the 100 Bq/m2 were deposited). Experiences considering the measurements in consequence of the contamination are discussed and improvements of the emergency planning are summarized.

  5. Recent numerical simulations and experiments on coolability of debris beds during severe accidents of light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Starflinger, J., E-mail: joerg.starflinger@ike.uni-stuttgart.de; Buck, M.; Hartmann, A.; Kulenovic, R.; Leininger, S.; Rahman, S.; Rashid, M.

    2015-12-01

    Highlights: • Investigation on coolability of three-dimensional debris beds has been performed. • Computer code MEWA (Melt Water) is introduced and described briefly. • Validation experiments have been carried out in DEBRIS facility. • Comparison of MEWA simulations and DEBRIS experiments show good agreement. • Example simulation on reactor scale was performed to explain the analysis method. - Abstract: In the course of a severe accident in light water reactors with core degradation, so-called debris beds can be formed inside the reactor pressure vessel or in the reactor cavity. The strategy to analyse the coolability of such debris beds with both experiments and numerical simulations is discussed. The numerical simulations are carried out with MEWA (MElt WAter) code, being developed at the institute for the prediction of the thermal-hydraulic conditions inside a debris bed, including the prediction of dryout heat flux. The simulations show good agreement with experimental data of the DEBRIS experiments.

  6. Calculations of reactor-accident consequences, Version 2. CRAC2: computer code user's guide

    Energy Technology Data Exchange (ETDEWEB)

    Ritchie, L.T.; Johnson, J.D.; Blond, R.M.

    1983-02-01

    The CRAC2 computer code is a revision of the Calculation of Reactor Accident Consequences computer code, CRAC, developed for the Reactor Safety Study. The CRAC2 computer code incorporates significant modeling improvements in the areas of weather sequence sampling and emergency response, and refinements to the plume rise, atmospheric dispersion, and wet deposition models. New output capabilities have also been added. This guide is to facilitate the informed and intelligent use of CRAC2. It includes descriptions of the input data, the output results, the file structures, control information, and five sample problems.

  7. An analysis of thermionic space nuclear reactor power system: I. Effect of disassembling radial reflector, following a reactivity initiated accident

    Science.gov (United States)

    El-Genk, Mohamed S.; Paramonov, Dmitry

    1993-01-01

    An analysis is performed to determine the effect of disassembling the radial reflector of the TOPAZ-II reactor, following a hypothetical severe Reactivity Initiated Accident (RIA). Such an RIA is assumed to occur during the system start-up in orbit due to a malfunction of the drive mechanism of the control drums, causing the drums to rotate the full 180° outward at their maximum speed of 1.4°/s. Results indicate that disassembling only three of twelve radial reflector panels would successfully shutdown the reactor, with little overheating of the fuel and the moderator.

  8. Study on operation of a research reactor during one PCS pump failure accident

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Kyoung Woo; Yoon, Hyu Ngi; Kim, Seong Hoon; Chi, Dae Young; Yoon, Juh Yeon [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    The Primary cooling system (PCS) of a research reactor is designed to provide adequate cooling to the reactor core with a reasonable margin during all operation modes. The PCS consists of pumps, heat exchangers, and all necessary interconnecting pipes, valves, and instruments. The number of pumps is determined from a safety and economic point of view. As the number of pump trains increase, the cost increases according to the increase in safety class equipment. However, it is impossible to install one pump for a PCS because a zero flow can instantaneously occur during a pump failure such as a pump seizure. Thus, a PCS frequently consists of two parallel 50% capacity pumps and heat exchangers. In addition, check valves are generally installed to prevent a reversal flow when multiple pumps are designed to operate. However, if a swing type check valve is used, it should be estimated whether the slam due to instantaneous closing of the valve affects the system vibration. To reduce the vibration by a slam phenomenon, additional equipment such as a damper will be installed in the valve. The purpose of the check valve in PCS is to prevent the flow path when a reverse flow occurs. The installation of additional equipment will make it difficult to perform this function. In this study, it is estimated whether the PCS can operate without check valves. First, a flow analysis using Flowmaster was compared and verified by the calculation employing a empirical correlation. Second, the simulation for a one pump failure accident was performed and analyzed.

  9. Dosimetry for a study of low-dose radiation cataracts among Chernobyl clean-up workers.

    Science.gov (United States)

    Chumak, V V; Worgul, B V; Kundiyev, Y I; Sergiyenko, N M; Vitte, P M; Medvedovsky, C; Bakhanova, E V; Junk, A K; Kyrychenko, O Y; Musijachenko, N V; Sholom, S V; Shylo, S A; Vitte, O P; Xu, S; Xue, X; Shore, R E

    2007-05-01

    A cohort of 8,607 Ukrainian Chernobyl clean-up workers during 1986-1987 was formed to study cataract formation after ionizing radiation exposure. Study eligibility required the availability of sufficient exposure information to permit the reconstruction of doses to the lens of the eye. Eligible groups included civilian workers, such as those who built the "sarcophagus" over the reactor, Chernobyl Nuclear Power Plant Workers, and military reservists who were conscripted for clean-up work. Many of the official doses for workers were estimates, because only a minority wore radiation badges. For 106 military workers, electron paramagnetic resonance (EPR) measurements of extracted teeth were compared with the recorded doses as the basis to adjust the recorded gamma-ray doses and provide estimates of uncertainties. Beta-particle doses to the lens were estimated with an algorithm devised to take into account the nature and location of Chernobyl work, time since the accident, and protective measures taken. A Monte Carlo routine generated 500 random estimates for each individual from the uncertainty distributions of the gamma-ray dose and of the ratio of beta-particle to gamma-ray doses. The geometric mean of the 500 combined beta-particle and gamma-ray dose estimates for each individual was used in the data analyses. The median estimated lens dose for the cohort was 123 mGy, while 4.4% received >500 mGy.

  10. CONTRIBUTON OF DIFFERENT FOODSTUFFS TО THE INTERNAL EXPOSURE OF THE RURAL INHABITANTS OF THE BRYANSK REGION IN RUSSIA AFTER THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. G. Travnikova

    2013-01-01

    Full Text Available In a large village Veprin of the Bryanskregion of Russiacontaminated with radionuclides as a result of the Chernobylaccident, 137Сs concentration in food products of agricultural produce and natural origin was regularly measured, local inhabitants were polled on the composition of their food ration, and 137Сs content in their bodies was at the same time measured. These results were used as the basis for calculation of annual effective doses of internal exposure to inhabitants and for reconstruction of the dose during the entire period after the accident. It will be divided into two stages: 1986–1996 yy and 1997–2012 yy. In this paper devoted to the first period (1986–1996, internal dose was reconstructed for 11 years after the accident, and the efficiency of countermeasures performed for reduction of the internal dose was assessed. The internal dose to inhabitants during the past 11 years after the accident was shown to be reduced almost twice, namely down to 35 mSv instead of the expected 70 mSv. The dose of external gamma radiation during the same time period is close to the obtained dose of internal exposure. The presence of peat and water-meadow soils in the vicinity of this village that are characterised by high transfer factors for radionuclides from soil to vegetation causes high contribution of internal exposure in the total dose of population exposure. Contribution of natural products to the internal dose grew from 6% in 1987 up to 25% in 1996. Individual content of 137Сs in the body of inhabitants reliably correlates with the consumption of milk in the early period after the accident and with consumption of forest mushrooms in the remote period.

  11. VICTORIA: A mechanistic model of radionuclide behavior in the reactor coolant system under severe accident conditions. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Heams, T J [Science Applications International Corp., Albuquerque, NM (United States); Williams, D A; Johns, N A; Mason, A [UKAEA, Winfrith, (England); Bixler, N E; Grimley, A J [Sandia National Labs., Albuquerque, NM (United States); Wheatley, C J [UKAEA, Culcheth (England); Dickson, L W [Atomic Energy of Canada Ltd., Chalk River, ON (Canada); Osborn-Lee, I [Oak Ridge National Lab., TN (United States); Domagala, P; Zawadzki, S; Rest, J [Argonne National Lab., IL (United States); Alexander, C A [Battelle, Columbus, OH (United States); Lee, R Y [Nuclear Regulatory Commission, Washington, DC (United States)

    1992-12-01

    The VICTORIA model of radionuclide behavior in the reactor coolant system (RCS) of a light water reactor during a severe accident is described. It has been developed by the USNRC to define the radionuclide phenomena and processes that must be considered in systems-level models used for integrated analyses of severe accident source terms. The VICTORIA code, based upon this model, predicts fission product release from the fuel, chemical reactions involving fission products, vapor and aerosol behavior, and fission product decay heating. Also included is a detailed description of how the model is implemented in VICTORIA, the numerical algorithms used, and the correlations and thermochemical data necessary for determining a solution. A description of the code structure, input and output, and a sample problem are provided.

  12. Simulation of a nuclear accident by an academic simulator of a VVER-1000 reactor; Simulacion de un accidente nuclear, mediante un simulador academico de un reactor VVER-1000

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez G, L. [UNAM, Facultad de Ingenieria, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Salazar S, E., E-mail: laurahg42@gmail.com [UNAM, Facultad de Ingenieria, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, 62250 Jiutepec, Morelos (Mexico)

    2014-10-15

    This work is planned to simulate a scenario in which the same conditions that caused the accident at the Fukushima Daichi nuclear power plant are present, using a simulator of a nuclear power plant with VVER-1000 reactor, a different type of technology to the NPP where the accident occurred, which used BWR reactors. The software where it will take place the simulation was created and distributed by the IAEA for academic purposes, which contains the essential systems that characterize this type of NPP. The simulator has tools for the analysis of the characteristic phenomena of a VVER-1000 reactor in the different systems together and planned training tasks. This makes possible to identify the function of each component and how connects to other systems, thus facilitating the visualization of possible failures and the consequences that they have on the general behavior of the reactor. To program the conditions in the simulator, is necessary to know and synthesize a series of events occurred in Fukushima in 2011 and the realized maneuvers to reduce the effects of the system failures. Being different technologies interpretation of the changes that would suffer the VVER systems in the scenario in question will be developed. The Fukushima accident was characterized by the power loss of regular supply and emergency of the cooling systems which resulted in an increase in reactor temperature and subsequent fusion of their nuclei. Is interesting to reproduce this type of failure in a VVER, and extrapolate the lack of power supply in the systems that comprise, as well as pumping systems for cooling, has a pressure regulating system which involves more variables in the balance of the system. (Author)

  13. A comprehensive evaluation of health effects in Europe-two decades after Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, C.; Maringer, F.J. [University of Natural Resources and Applied Life Science Vienna, Low-Level Counting Lab. Arsenal, Wien (Austria); Maringer, F.J. [BEV-Federal Office of Metrology and Surveying (BEV), Wien (Austria); Bossew, P. [BEV-Federal Office of Metrology and Surveying (BEV), Mathematics and analytics, Vienna (Austria)

    2006-07-01

    This report sums up radioactive environmental contamination due to the Chernobyl accident in 1986 in various regions all over Europe (Ukraine, Belarus, Russia, Sweden, Austria and Greece). Most of the radionuclides released with the reactor accident possess short-lives (e.g. 131 I) of a few hours or several days and weeks or were deposed in low quantities (e.g. 90 Sr). So the main focus was put on 137 Cs, because this radionuclide has a long half-life (30 years), is measurable till this day and gives a presentable view of radiation exposure in contaminated regions. The decrease of 137 Cs activity concentrations in soil, surface water, foodstuffs and air was shown in the course of time. The comparison of radioactive environmental contamination shows, that the 137 Cs-activity concentration in nearly all media has decreased faster than the physical half-life. Part of this elaboration was also to describe the contribution of the reactor accident to the radiation exposure of selected population groups in the last 20 years. The second part of the report follows a valuation of European studies, which are linked to late health effects of the Chernobyl accident specially thyroid cancer, leukaemia and other solid tumours. These studies has been discussed and evaluated. Only in countries with the highest impact like Ukraine, Belarus and Russia, an increased number of infant thyroid cancer has been observed but up to now no increases in leukaemia or malignant deceases in this or other European countries can be detected. (authors)

  14. Upgrading the electrical system of the IEA-R1 reactor to avoid triggering event of accidents

    Energy Technology Data Exchange (ETDEWEB)

    Mello, Jose Roberto de; Madi Filho, Tufic, E-mail: jrmello@ipen.br, E-mail: tmfilho@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The IEA-R1 research reactor at the Institute of Energy and Nuclear Research (IPEN) is a research reactor open pool type, built and designed by the American firm 'Babcox and Wilcox', having as coolant and moderator demineralized light water and Beryllium and graphite, as reflectors. The power supply system is designed to meet the electricity demand required by the loads of the reactor (Security systems and systems not related to security) in different situations the plant can meet, such as during startup, normal operation at power, shutdown, maintenance, exchange of fuel elements and accident situations. Studies have been done on possible accident initiating events and deterministic techniques were applied to assess the consequences of such incidents. Thus, the methods used to identify and select the accident initiating events, the methods of analysis of accidents, including sequence of events, transient analysis and radiological consequences, have been described. Finally, acceptance criteria of radiological doses are described. Only a brief summary of the item concerning loss of electrical power will be presented. The loss of normal electrical power at the IEA-R1 reactor is very common. In the case of Electric External Power Loss, at the IEA-R1 reactor building, there may be different sequences of events, as described below. When the supply of external energy in the IEA-R1 facility fails, the Electrical Distribution Vital System, consisting of 4 (four) generators type 'UPS', starts operation, immediately and it will continue supplying power to the reactor control table, core cooling system and other security systems. To contribute to security, in the electric power failure, starts to operate the Emergency Cooling System (SRE). SRE has the function of removing residual heat from the core to prevent the melting of fuel elements in the event of loss of refrigerant to the core. Adding to the generators with batteries group system, new auxiliary

  15. Interfacing systems LOCAs (Loss of Coolant Accidents) at boiling water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Tsong-Lun; Fitzpatrick, R.; Stoyanov, S.

    1987-01-01

    The work presented in this paper was performed by Brookhaven National Laboratory (BNL) in support of Nuclear Regulatory Commission's (NRC) effort towards the resolution of Generic Issue 105 ''Interfacing System Loss of Coolant Accidents (LOCAs) at Boiling Water Reactors (BWRs).'' For BWRs, intersystem LOCA have typically either not been considered in probabilistic risk analyses, or if considered, were judged to contribute little to the risk estimates because of their perceived low frequency of occurrence. However, recent operating experience indicates that the pressure isolation valves (PIVs) in BWRs may not adequately protect against overpressurization of low pressure systems. The objective of this paper is to present the results of a study which analyzed interfacing system LOCA at several BWRs. The BWRs were selected to best represent a spectrum of BWRs in service using industry operating event experience and plant-specific information/configurations. The results presented here include some possible changes in test requirements/practices as well as an evaluation of their reduction potential in terms of core damage frequency (CDF).

  16. Fukushima Daiichi Unit 1 Accident Progression Uncertainty Analysis and Implications for Decommissioning of Fukushima Reactors - Volume I.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mattie, Patrick D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    Sandia National Laboratories (SNL) has conducted an uncertainty analysis (UA) on the Fukushima Daiichi unit (1F1) accident progression with the MELCOR code. The model used was developed for a previous accident reconstruction investigation jointly sponsored by the US Department of Energy (DOE) and Nuclear Regulatory Commission (NRC). That study focused on reconstructing the accident progressions, as postulated by the limited plant data. This work was focused evaluation of uncertainty in core damage progression behavior and its effect on key figures-of-merit (e.g., hydrogen production, reactor damage state, fraction of intact fuel, vessel lower head failure). The primary intent of this study was to characterize the range of predicted damage states in the 1F1 reactor considering state of knowledge uncertainties associated with MELCOR modeling of core damage progression and to generate information that may be useful in informing the decommissioning activities that will be employed to defuel the damaged reactors at the Fukushima Daiichi Nuclear Power Plant. Additionally, core damage progression variability inherent in MELCOR modeling numerics is investigated.

  17. CHERNOBYL HEALTH RADIOLOGICAL EFFECTS ON THE POPULATION OF RUSSIA: DATA OF THE NATIONAL REGISTRY

    Directory of Open Access Journals (Sweden)

    V. K. Ivanov

    2008-01-01

    Full Text Available Summarized radiation-epidemiological data on health effects of the accident at the Chernobyl NPP registered in the follow-up period 1986-2006 on the Russian population are reported. Two groups of population: Chernobyl Emergency accident workers and residents of the most contaminated with radionuclides territories are examined. Impact of radiation-associated risk of solid cancers and leukaemia in these groups is assessed. Prognostic estimates of health effects of the Chernobyl accident on the Russian population are offered in the article.

  18. Coolability of corium debris under severe accident conditions in light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Saidur

    2013-11-15

    The debris bed which may be formed in different stages of a severe accident will be hot and heated by decay heat from the radioactive fission products. In order to establish a steady state of long-term cooling, this hot debris needs to be quenched at first. If quenching by water ingression into the dry bed is not rapid enough then heat-up by decay heat in still dry regions may again yield melting. Thus, chances of coolability must be investigated considering quenching against heat-up due to decay heat, in the context of reactor safety research. As a basis of the present investigations, models for simulation of two phase flow through porous medium were already available in the MEWA code, being under development at IKE. The objective of this thesis is to apply the code in essential phases of severe accidents and to investigate the chances, options and measures for coolability. Further, within the tasks, improvements to remove weaknesses in modeling and implementation of extensions concerning missing parts are included. It was identified previously that classical models without explicit considering the interfacial friction, can predict dryout heat flux (DHF) well under top fed condition but under-predict DHF values under bottom flooding conditions. Tung and Dhir introduced an interfacial friction term in their model, but this model has deficits for smaller particles considered as relevant for reactor conditions. Therefore, some modification of Tung and Dhir model is proposed in the present work to extent it for smaller particles. A significant improvement with the new friction description (Modified Tung and Dhir, MTD) is obtained considering the aim of a unified description for both top and bottom flooding conditions and for broad bandwidth of bed conditions. Calculations for reactor conditions are carried out in order to explore whether or to which degree coolability can be concluded, how strong the trend to coolability is and where major limits occur. The general

  19. ASSESSMENT OF THE AVERAGE ANNUAL EFFECTIVE DOSES FOR THE INHABITANTS OF THE SETTLEMENTS LOCATED IN THE TERRITORIES CONTAMINATED DUE TO THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    N. G. Vlasova

    2012-01-01

    Full Text Available Catalogue of the average annual effective exposure doses of the inhabitants of the territories contaminated due to the Chernobul accident had been developed according to the method of the assessment of the average annual effective exposure doses of the settlements inhabitants. The cost-efficacy of the use of the average annual effective dose assessment method was 250 000 USD for the current 5 years. Average annual effective dose exceeded 1 mSv/year for 191 Belarus settlements from 2613. About 50 000 persons are living in these settlements.

  20. Community emergency response to nuclear power plant accidents: A selected and partially annotated bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Youngen, G.

    1988-10-01

    The role of responding to emergencies at nuclear power plants is often considered the responsibility of the personnel onsite. This is true for most, if not all, of the incidents that may happen during the course of the plant`s operating lifetime. There is however, the possibility of a major accident occurring at anytime. Major nuclear accidents at Chernobyl and Three Mile Island have taught their respective countries and communities a significant lesson in local emergency preparedness and response. Through these accidents, the rest of the world can also learn a great deal about planning, preparing and responding to the emergencies unique to nuclear power. This bibliography contains books, journal articles, conference papers and government reports on emergency response to nuclear power plant accidents. It does not contain citations for ``onsite`` response or planning, nor does it cover the areas of radiation releases from transportation accidents. The compiler has attempted to bring together a sampling of the world`s collective written experience on dealing with nuclear reactor accidents on the sate, local and community levels. Since the accidents at Three Mile Island and Chernobyl, that written experience has grown enormously.

  1. IODINE-129 in soils from northern Ukraine and the retrospective dosimetry of the IODINE-131 exposure after the Chernobyl accident; IODINE-129 in Boeden der noerdlichen Ukraine und die retrospektive Dosimetrie der IODINE-131-Exposition nach dem Unfall von Tschernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Daraoui, A.; Michel, R.; Gorny, M.; Jakob, D.; Korntheuer, J.; Sachse, R. [Zentrum fuer Strahlenschutz and Radiooekologie, Leibniz Univ. Hannover (Germany); Alfimov, V.; Synal, H.A. [Lab. fuer Ionenstrahlphysik (LIP), ETH Zuerich (Switzerland)

    2009-07-01

    With the help of the long-lived {sup 129}I a retrospective dosimetry of the {sup 131}I exposure after the Chernobyl accident can be achieved in the highly contaminated zone in Ukraine. 300 soil samples down to a depth of 40 cm and 3 soil profiles to a depth of 200 cm were taken from 60 villages in contamination zone II und III in northern Ukraine in 2004 and 2007. {sup 129}I/{sup 127}I was analysed by AMS and {sup 127}I was determined by ICP-MS. The results from the soil profiles show that more than 90% of the {sup 129}I-concentrations in the soil profiles are still located in the top 40 cm of the profiles. This allows using the {sup 129}I inventories in the soil samples down to 40 cm depth as proxies for the total anthropogenic {sup 129}I inventories. The {sup 129}I- und {sup 137}Cs- inventories are correlated in the highly contaminated areas. However, the variability of the {sup 129}I/{sup 137}Cs ratios is large, so that for the retrospective dosimetry one has to rely on {sup 129}I. In 35 villages in the contamination zone II, the mean thyroid doses were 1.9 x 3.2{sup {+-}}{sup 1} Gy for 5-year-old children and 0.45 x 3.2{sup {+-}}{sup 1} Gy for adults. In 25 locations in the contamination zone III, the mean thyroid doses were 0.75 x 1.9{sup {+-}}{sup 1} Gy for 5-year-old children and 0.18 x 1.9{sup {+-}}{sup 1} Gy for adults. (orig.)

  2. Numerical simulation of a Hypothetical Core Disruptive Accident in a small-scale model of a nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Robbe, M.F. E-mail: robbe@aquilon.cea.frmfrobbe@cea.fr; Lepareux, M.; Treille, E.; Cariou, Y

    2003-08-01

    In the case of a Hypothetical Core Disruptive Accident (HCDA) in a Liquid Metal Fast Breeder Reactor, it is assumed that the core of the nuclear reactor has melted partially and that the chemical interaction between molten fuel and liquid sodium has created a high-pressure gas bubble in the core. The violent expansion of this bubble loads and deforms the reactor vessel and the internal structures, thus endangering the safety of the nuclear plant. The MARA 10 experimental test simulates a HCDA in a 1/30-scale mock-up schematising a reactor block. In the mock-up, the liquid sodium cooling the reactor core is replaced by water and the argon blanket laying below the reactor roof is simulated by an air blanket. The explosion is triggered by an explosive charge. This paper presents a numerical simulation of the test with the EUROPLEXUS code and an analysis of the computed results. In particular, the evolution of the fluid flows and the deformations of the internal and external structures are analysed in detail. Finally, the current computed results are compared with the experimental ones and with previous numerical results computed with the SIRIUS and CASTEM-PLEXUS codes.

  3. Modelling of the transfer of CS-137 from air to crops, milk, beef and human body following the Chernobyl accident, in a location in Central Bohemia. Test of the model PRYMA T1; Modelizacion de la transferencia de CS-137 desde el aire a las cosechas, la leche, la carne de vacuno y el cuerpo humano producido por el accidente de Chernobyl, en una localizacion en la Bohemia Central. Test del modelo PRYMA T1

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, E.; Garcia-Olivares, A.; Suaez, A.; Robles, B. Simon, I.; Cancio, D.

    1994-07-01

    This work was made in the frame of the research programme on validation of models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. The acronym of this programme is VAMP (Validation of Model Predictions) and is coordinated by the International Atomic Energy Agency (IAEA) and the Commission of the European Communities (CEC). The scenario was named CB and was presented by the Multiple Pathway Working group. The scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. The input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and more description of the scenario (data about crops, cattele, demography, human diet, etc.). The aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed.

  4. 30 years life with Chernobyl, 5 years life with Fukushima. Health consequences of the nuclear catastrophes of Chernobyl and Fukushima; 30 Jahre Leben mit Tschernobyl, 5 Jahre Leben mit Fukushima. Gesundheitliche Folgen der Atomkatastrophen von Tschernobyl und Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Claussen, Angelika; Rosen, Alex

    2016-02-15

    The IPPNW report on health consequences of the nuclear catastrophes of Chernobyl and Fukushima covers the following issues: Part.: 30 years life with Chernobyl: Summarized consequences of Chernobyl, the accident progression, basic data of the catastrophe, estimation of health hazards as a consequence of the severe accident of Chernobyl, health consequences for the liquidators, health consequences for the contaminated population, mutagenic and teratogenic effects. Part B: 5 years life with Fukushima: The start of the nuclear catastrophe, emissions and contamination, consequences of the nuclear catastrophe on human health, thyroid surveys in the prefecture Fukushima, consequences of the nuclear catastrophe on the ecosystem, outlook.

  5. The SAM software system for modeling severe accidents at nuclear power plants equipped with VVER reactors on full-scale and analytic training simulators

    Science.gov (United States)

    Osadchaya, D. Yu.; Fuks, R. L.

    2014-04-01

    The architecture of the SAM software package intended for modeling beyond-design-basis accidents at nuclear power plants equipped with VVER reactors evolving into a severe stage with core melting and failure of the reactor pressure vessel is presented. By using the SAM software package it is possible to perform comprehensive modeling of the entire emergency process from the failure initiating event to the stage of severe accident involving meltdown of nuclear fuel, failure of the reactor pressure vessel, and escape of corium onto the concrete basement or into the corium catcher with retention of molten products in it.

  6. Downward migration of Chernobyl-derived radionuclides in soils in Poland and Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Matisoff, Gerald, E-mail: gerald.matisoff@case.edu [Case Western Reserve University, Cleveland, OH 44106-7216 (United States); Ketterer, Michael E. [Northern Arizona University, Flagstaff, AZ 86011-5698 (United States); Rosen, Klas [Swedish University of Agricultural Sciences, Uppsala (Sweden); Mietelski, Jerzy W. [Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Vitko, Lauren F. [Case Western Reserve University, Cleveland, OH 44106-7216 (United States); Persson, Henning [Swedish University of Agricultural Sciences, Uppsala (Sweden); Lokas, Edyta [Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland)

    2011-01-15

    Research highlights: {yields} {sup 137}Cs and {sup 239,240}Pu move down into the soil profile. {yields} {sup 137}Cs is from Chernobyl fallout; {sup 239,240}Pu is from stratospheric fallout from the 1960s. {yields} Solute transport and bioturbation models describe some but not all of the radionuclide profiles. - Abstract: Vertical profiles of {sup 137}Cs and {sup 239,240}Pu were measured in soils collected from two sites in southern Sweden and three sites in southern Poland and were modeled using both a solute transport model and a bioturbation model to better understand their downward migration. A time series of measured {sup 137}Cs profiles indicates that {sup 137}Cs from Chernobyl was found at the soil surface in 1986 but it has migrated progressively downward into the soil 4.5-25.5 cm since. However, because of dispersion during the migration and mixing following Chernobyl deposition and the much higher activities of {sup 137}Cs from Chernobyl, stratospheric fallout of {sup 137}Cs from the 1960s cannot be identified as a second {sup 137}Cs activity maximum lower in the soil column at any of the sites. Conversely, the {sup 240}Pu/{sup 239}Pu ratio indicates that no Chernobyl-derived Pu is present in any of the cores with the exception of one sample in Sweden. This difference may be attributed to the nature of the release from Chernobyl. Cesium volatilized at the reactor temperature during the accident, and was released as a vapor whereas Pu was not volatile and was only released in the form of minute fuel particles that traveled regionally. Both the solute diffusion and the bioturbation models accurately simulate the downward migration of the radionuclides at some sites but poorly describe the distributions at other sites. The distribution coefficients required by the solute transport model are about 100 times lower than reported values from the literature indicating that even though the solute transport model can simulate the profile shapes, transport as a

  7. Heating of reactor pressure vessel bottom head and penetrations in a severe reactor accident; Reaktoripaineastian pohjan ja laepivientien kuumeneminen sydaemen sulamisonnettomuudessa

    Energy Technology Data Exchange (ETDEWEB)

    Ikonen, K. [VTT Energy, Espoo (Finland). Nuclear Energy

    1997-10-01

    The report describes the fundamentals of heat conductivity and convection and numerical methods like finite difference and control volume method for calculation of the thermal history of a reactor pressure vessel bottom head and penetrations. Phase changes from solids to liquids are considered. Time integration is performed by explicit or implicit method. Developed computer codes for thermal conductivity and convection analyses and codes for graphical visualization are described. The codes are applied to two practical cases. They deal with analyses of Swiss CORVIS-experiments and analyses of control rod and instrument penetrations in a BWR bottom head. A model for calculation of effective thermal conductivity of granular corium is developed. The work is also related to EU MVI-project (Core Melt-Pressure Vessel Interactions During a Light Water Reactor Severe Accident), whose coordinator is Prof. B. R. Sehgal at Royal Institute of Technology in Stockholm. (orig.) (11 refs.).

  8. Chernobyl - state of the art; Chernobyl - o estado da arte

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Daiane C.B. de; Vicente, Roberto; Rostelato, Maria Elisa C.M.; Borges, Jessica F.; Tiezzi, Rodrigo; Peleias Junior, Fernando S.; Souza, Carla D.; Rodrigues, Bruna T.; Benega, Marcos A.G.; Souza, Anderson S. de; Silva, Thais H. da, E-mail: dcsouza@ipen.br, E-mail: rvicente@ipen.br, E-mail: elisaros@ipen.br, E-mail: rtiezzi@ipen.br, E-mail: carladdsouza@yahoo.com.br, E-mail: marcosagbenega@ipen.br, E-mail: bteigarodrigues@gmail.com, E-mail: thaishunk@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-07-01

    This article aims to analyze what has been done so far in relation to damage caused by the accident and the state of art in Chernobyl, as well as the impact on radiation protection applied safety nuclear power plants. In the first part of the work a data survey was done through a bibliographic review and the in the second part data was collected during a visit, in June 2013 at the crash site, when was observed dose values in the affected areas and the works of repairs that have been made in the sarcophagus and surroundings as well as in official reports available through active international bodies. The main results indicate significant improvements in radiation protection systems.

  9. The study of core melting phenomena in reactor severe accident of PWR

    Energy Technology Data Exchange (ETDEWEB)

    Jeun, Gyoo Dong; Cho, Sung Won; Bang, Kwang Hyun; Park, Shane; Park, Seong Yong; Kim, Jin Man; Lim, Jae Hyuck; Song, Myung Jin [Hanyang Univ., Seoul (Korea, Republic of)

    2000-03-15

    TMI-2 accident is more valuable than the related experiments in the point of view that it is a real accident offering huge information about the late phase of severe accident. Therefore it gives out good standards for evaluation of code performance and inputs suitableness by comparing the accident data and simulated outputs. In this study SCDAP/REALAP5/MOD3.4 was selected for accident simulation. And sensitivity analysis was performed on varied cases to find out the most proper input variable about the late phase of core meting phenomena. Other plants and experimental facilities input deck were collected and analyzed for the sensitivity study and the shortcomings proposed by SCDAP/RELAP5 peer review were considered to the simulation. As a result gamma heating fraction in the input affect the progress of core melting phenomena. About this a study on the related model itself will be carried out.

  10. Fallout: The experiences of a medical team in the care of a Marshallese population accidently exposed to fallout radiation

    Energy Technology Data Exchange (ETDEWEB)

    Conard, R.A.

    1992-09-01

    This report presents an historical account of the experiences of the Brookhaven Medical Team in the examination and treatment of the Marshallese people following their accidental exposure to radioactive fallout in 1954. This is the first time that a population has been heavily exposed to radioactive fallout, and even though this was a tragic mishap, the medical findings have provided valuable information for other accidents involving fallout such as the recent reactor accident at Chernobyl. Noteworthy has been the unexpected importance of radioactive iodine in the fallout in producing thyroid abnormalities.

  11. Large-break loss-of-coolant accident phenomena identification and ranking table (PIRT) for the advanced Candu reactor

    Energy Technology Data Exchange (ETDEWEB)

    Popov, N.; Snell, V.G.; Sills, H.E.; Langman, V.J.; Boyack, B. [Atomic Energy of Canada Ltd (Canada)

    2004-07-01

    The Advanced Candu Reactor (ACR) is an evolutionary advancement of the current Candu-6 reactor, aimed at producing electrical power for a capital cost and unit-energy cost significantly less than that of current reactor designs. The ACR retains the modular concept of horizontal fuel channels surrounded by heavy water moderator, as with all Candu reactors. However, ACR uses slightly enriched uranium (SEU) fuel, compared to the natural uranium used in Candu 6. This achieves the twin goals of improved economics (e.g., via reductions in the heavy water requirements and the use of a light water coolant), as well as improved safety. This paper is focused on the double-ended guillotine critical inlet header break (CRIHB) loss-of-coolant accident (LOCA) in an ACR reactor, which is considered as a large break LOCA. Large Break LOCA in water-cooled reactors has been used historically as a design basis event by regulators, and it has attracted a very large share of safety analysis and regulatory review. The LBLOCA event covers a wide range of system behaviours and fundamental phenomena. The Phenomena Identification and Ranking Table (PIRT) for LBLOCA therefore provides a good understanding of many of the safety characteristics of the ACR design. The paper outlines the design characteristics of the ACR reactor that impact the PIRT process and computer code applicability. It also describes the LOCA phenomena, lists all components and systems that have an important role during the event, discusses the PIRT process and results, and presents the final PIRT summary table. (authors)

  12. KIT multi-physics tools for the analysis of design and beyond design basis accidents of light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Victor Hugo; Miassoedov, Alexei; Steinbrueck, M.; Tromm, W. [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany)

    2016-05-15

    This paper describes the KIT numerical simulation tools under extension and validation for the analysis of design and beyond design basis accidents (DBA) of Light Water Reactors (LWR). The description of the complex thermal hydraulic, neutron kinetics and chemo-physical phenomena going on during off-normal conditions requires the development of multi-physics and multi-scale simulations tools which are fostered by the rapid increase in computer power nowadays. The KIT numerical tools for DBA and beyond DBA are validated using experimental data of KIT or from abroad. The developments, extensions, coupling approaches and validation work performed at KIT are shortly outlined and discussed in this paper.

  13. Preliminary phenomena identification and ranking tables for simplified boiling water reactor Loss-of-Coolant Accident scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Kroeger, P.G.; Rohatgi, U.S.; Jo, J.H.; Slovik, G.C.

    1998-04-01

    For three potential Loss-of-Coolant Accident (LOCA) scenarios in the General Electric Simplified Boiling Water Reactors (SBWR) a set of Phenomena Identification and Ranking Tables (PIRT) is presented. The selected LOCA scenarios are typical for the class of small and large breaks generally considered in Safety Analysis Reports. The method used to develop the PIRTs is described. Following is a discussion of the transient scenarios, the PIRTs are presented and discussed in detailed and in summarized form. A procedure for future validation of the PIRTs, to enhance their value, is outlined. 26 refs., 25 figs., 44 tabs.

  14. Aerial Measurement of Radioxenon Concentration off the West Coast of Vancouver Island following the Fukushima Reactor Accident

    CERN Document Server

    Sinclair, L E; Fortin, R; Carson, J M; Saull, P R B; Coyle, M J; Van Brabant, R A; Buckle, J L; Desjardins, S M; Hall, R M

    2011-01-01

    In response to the Fukushima nuclear reactor accident, on March 20th, 2011, Natural Resources Canada conducted aerial radiation surveys over water just off of the west coast of Vancouver Island. Dose-rate levels were found to be consistent with background radiation, however a clear signal due to Xe-133 was observed. Methods to extract Xe-133 count rates from the measured spectra, and to determine the corresponding Xe-133 volumetric concentration, were developed. The measurements indicate that Xe-133 concentrations on average lie in the range of 30 to 70 Bq/m3.

  15. The lesson of the Chernobyl disaster

    Energy Technology Data Exchange (ETDEWEB)

    Milhaud, G. (Hopital Saint-Antoine, 75 Paris (FR))

    1991-01-01

    On april 26, 1986 a major nuclear disaster took place at 1 h 24 min local time, destroying the fourth reactor of the Chernobyl plant. Five years later the consequences of the disaster are still not fully known. Nevertheless the long term future of nuclear energy in the world is uncertain. Questions need to be answered by observing hard facts if emotional attitudes are not to prevail over reality. The reactor and its core were destroyed by an explosion, causing two radioactive jet emissions of iodine 131, followed by caesium 137. Both elements are mainly incorporated in the body via food. The Chernobyl disaster was a consequence of inadequate safety regulations and human error. Enforcement of strict regulations are likely to be highly effective in preventing a further catastrophe. However, governments should consider another possibility. What would be the consequences for public health if a terroristic act deliberately destroyed a nuclear power station.

  16. Simulating Experimental Investigation on the Safety of Nuclear Heating Reactor in Loss—of —Coolant Accidents

    Institute of Scientific and Technical Information of China (English)

    ZhanjieXu

    1996-01-01

    The 5MW low temperature nuclear heating reactor (NHR-5) is a new and advanced type of nuclear reactor developed by Institute of Nuclear Energy Technology(INET) of Tisinghuan University of CHina in 1989,Its main loop is a thermal-hydraulic system with natural circulation.This paper studies the safety of NHR under the condition of loss-of -coolant accidents(LOCAs) by means of simulant experiments.First,the Background and necessity of the experiments are presented.then the experimental system,including the thermal-hydraulic system and the data collection system,and similarity criteria are introduced.Up to now ,the discharge experiments with the residual heating power(20% rated heating power)have been carried out on the experimental system,The system prameters including circulation flow rate,system pressure,system temperature,void fraction,discharge mass and so on have been recorded and analyzed.Based on the results of the experiments,the conclusionas are shown as follos:on the whole,the reactor is safe under the condition of LOCAs,but the thermal vacillations resulting from the vibration of the circulation flow rate are disadvantageous to the internal parts of the reactor core.

  17. The consequences of the Chernobyl accident in the Ukraine and problems with the sarcophagus; Die Folgen der Katastrophe von Tschernobyl in der Ukraine und die Probleme mit dem Sarkophag

    Energy Technology Data Exchange (ETDEWEB)

    Kopchinsky, G.A. [Atomaudit, Kiew (Ukraine)

    1996-07-01

    The reactor accident in the Ukraine contaminated part of the territory with iodine 131, caesium 137, strontium 90, and plutonium 239 and 240. The zone surrounding the site of the accident was declared restricted area; more than 90 000 persons were evacuated. The paper reports on current conditions in the restricted area and prospects for this area as well as on the current state of, and problems with, the sarcophagus. The conversion of the sarcophagus into an ecologically safe system and the economic situation of the Ukraine pose great problems. (DG) [Deutsch] Durch den Reaktorunfall in der Ukraine ist ein Teil des Territoriums mit Jod 131, Caesium 137, Strontium 90, Plutonium 239 und -240 kontaminiert worden. Um den Unfallort wurde eine Isolierungszone geschaffen und mehr als 90.000 Menschen evakuiert. Ueber den Zustand und die Perspektiven der Isolierungszone sowie ueber den Zustand und die Probleme des Sarkophags wird berichtet. Die Umgestaltung des Sarkophags in ein oekologisch sicheres System und die wirtschaftliche Situation der Ukraine bereiten grosse Probleme. (DG)

  18. Neutron-activation analysis of hot particles from the vicinity of the Chernobyl Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lyul`, A.Yu.; Kolesov, G.M.; Cherkezyan, V.O. [V.I. Vernadskii Institute of Geochemistry and Analytical Chemistry, Moscow (Russian Federation)

    1994-04-10

    A considerable portion of the radioactive contamination of the surface layers of soil after the accident at the Chernobyl Nuclear Power Plant was caused by hot particles or aggregates with a diameter of several tens microns and a specific activity >n{center_dot}10{sup {minus}11} Ci. They consist of primary particles of the dispersed material of the nuclear fuel and secondary particles formed as a result of the interaction of the fuel and uranium fission products with the structural materials of the reactor and the destroyed active zone. The radionuclide composition of the hot particles characterizes the nuclear fuel used and the temperature conditions in the reactor during the first weeks after the accident and their chemical composition reflects the conditions and processes leading to their formation, which must be known in order; to ascertain the mechanism of the formation of the radioactive emission from the reactor and to evaluate the degree of ecological danger posed by the particles. All this promotes the urgency and importance of studying the radiation-chemical characteristics of such hot particles. Their small sizes and masses impose definite restrictions; on the investigative methods used, which must be highly sensitive and must offer the possibility of performing a nondestructive analysis. One such method is neutron-activation analysis. The purpose of the present investigation was to apply instrumental neutron-activation analysis to the simultaneous determination of the elemental composition of hot particles and establishment of the isotopic composition of the uranium in them.

  19. Accident source terms for pressurized water reactors with high-burnup cores calculated using MELCOR 1.8.5.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O.; Powers, Dana Auburn; Ashbaugh, Scott G.; Leonard, Mark Thomas; Longmire, Pamela

    2010-04-01

    In this study, risk-significant pressurized-water reactor severe accident sequences are examined using MELCOR 1.8.5 to explore the range of fission product releases to the reactor containment building. Advances in the understanding of fission product release and transport behavior and severe accident progression are used to render best estimate analyses of selected accident sequences. Particular emphasis is placed on estimating the effects of high fuel burnup in contrast with low burnup on fission product releases to the containment. Supporting this emphasis, recent data available on fission product release from high-burnup (HBU) fuel from the French VERCOR project are used in this study. The results of these analyses are treated as samples from a population of accident sequences in order to employ approximate order statistics characterization of the results. These trends and tendencies are then compared to the NUREG-1465 alternative source term prescription used today for regulatory applications. In general, greater differences are observed between the state-of-the-art calculations for either HBU or low-burnup (LBU) fuel and the NUREG-1465 containment release fractions than exist between HBU and LBU release fractions. Current analyses suggest that retention of fission products within the vessel and the reactor coolant system (RCS) are greater than contemplated in the NUREG-1465 prescription, and that, overall, release fractions to the containment are therefore lower across the board in the present analyses than suggested in NUREG-1465. The decreased volatility of Cs2MoO4 compared to CsI or CsOH increases the predicted RCS retention of cesium, and as a result, cesium and iodine do not follow identical behaviors with respect to distribution among vessel, RCS, and containment. With respect to the regulatory alternative source term, greater differences are observed between the NUREG-1465 prescription and both HBU and LBU predictions than exist between HBU and LBU

  20. Towards the prediction of the rupture of a pressurized water reactor vessel in case of accident; Vers la prevision du dechirement d'une cuve de reacteur a eau pressurisee en cas d'accident

    Energy Technology Data Exchange (ETDEWEB)

    Tardif, N.; Coret, M.; Combescure, A. [Lyon Univ., CNRS, INSA-Lyon, LaMCoS UMR5259, 69 (France); Tardif, N.; Nicaise, G. [Institut de Radioprotection et de Surete Nucleaire, DSR/SAGR/BPhAG, 92 - Fontenay-aux-Roses (France)

    2009-07-01

    Through a scale model of a reactor vessel submitted to a thermal and mechanical load during a severe accident, it is possible to follow the initiation and propagation of cracks in real time by tests carried out on laboratory. (O.M.)

  1. Chernobyl: the effects on public health?

    Energy Technology Data Exchange (ETDEWEB)

    Aurengo, A. [Hopital Pitie-Salpetriere, Dept. Nucleaire Medecine, 75 - Paris (France)

    2003-07-01

    Because of its public health, ecological and industrial consequences, the Chernobyl accident has become a myth which serves as the focus of many fears, justified or not. no one can question the seriousness of the event, but after fifteen years there is still no agreement about the effect it has had or will have on public health. For example, the total number of deaths attributed to Chernobyl varies from less than a hundred to several millions and congenital malformations from negligible to cataclysmic. Effects on public health may be calculated from data on contamination, from the dose received and from the risk, all three of which are likely to be very roughly known; or they may be evaluated on the spot, either by epidemiological studies or by examining medical registers. This report makes an inventory of the different risks and takes stock on them. (N.C.)

  2. Proceedings of the US Nuclear Regulatory Commission fifteenth water reactor safety information meeting: Volume 6, Decontamination and decommissioning, accident management, TMI-2

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, A. J. [comp.

    1988-02-01

    This six-volume report contains 140 papers out of the 164 that were presented at the Fifteenth Water Reactor Safety Information Meeting held at the National Bureau of Standards, Gaithersburg, Maryland, during the week of October 26-29, 1987. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. This report, Volume 6, discusses decontamination and decommissioning, accident management, and the Three Mile Island-2 reactor accident. Thirteen reports have been cataloged separately.

  3. Effect of spray system on fission product distribution in containment during a severe accident in a two-loop pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Dehjourian, Mehdi; Rahgoshay, Mohammad; Jahanfamia, Gholamreza [Dept. of Nuclear Engineering, Science and Research Branch, Islamic Azad University of Tehran, Tehran (Iran, Islamic Republic of); Sayareh, Reza [Faculty of Electrical and Computer Engineering, Kerman Graduate University of Technology, Kerman (Iran, Islamic Republic of); Shirani, Saied [Faculty of Engineering, Shahid Beheshti University, Tehran (Iran, Islamic Republic of)

    2016-08-15

    The containment response during the first 24 hours of a low-pressure severe accident scenario in a nuclear power plant with a two-loop Westinghouse-type pressurized water reactor was simulated with the CONTAIN 2.0 computer code. The accident considered in this study is a large-break loss-of-coolant accident, which is not successfully mitigated by the action of safety systems. The analysis includes pressure and temperature responses, as well as investigation into the influence of spray on the retention of fission products and the prevention of hydrogen combustion in the containment.

  4. Effect of Spray System on Fission Product Distribution in Containment During a Severe Accident in a Two-Loop Pressurized Water Reactor

    Directory of Open Access Journals (Sweden)

    Mehdi Dehjourian

    2016-08-01

    Full Text Available The containment response during the first 24 hours of a low-pressure severe accident scenario in a nuclear power plant with a two-loop Westinghouse-type pressurized water reactor was simulated with the CONTAIN 2.0 computer code. The accident considered in this study is a large-break loss-of-coolant accident, which is not successfully mitigated by the action of safety systems. The analysis includes pressure and temperature responses, as well as investigation into the influence of spray on the retention of fission products and the prevention of hydrogen combustion in the containment.

  5. Models and numerical methods for the simulation of loss-of-coolant accidents in nuclear reactors

    Science.gov (United States)

    Seguin, Nicolas

    2014-05-01

    In view of the simulation of the water flows in pressurized water reactors (PWR), many models are available in the literature and their complexity deeply depends on the required accuracy, see for instance [1]. The loss-of-coolant accident (LOCA) may appear when a pipe is broken through. The coolant is composed by light water in its liquid form at very high temperature and pressure (around 300 °C and 155 bar), it then flashes and becomes instantaneously vapor in case of LOCA. A front of liquid/vapor phase transition appears in the pipes and may propagate towards the critical parts of the PWR. It is crucial to propose accurate models for the whole phenomenon, but also sufficiently robust to obtain relevant numerical results. Due to the application we have in mind, a complete description of the two-phase flow (with all the bubbles, droplets, interfaces…) is out of reach and irrelevant. We investigate averaged models, based on the use of void fractions for each phase, which represent the probability of presence of a phase at a given position and at a given time. The most accurate averaged model, based on the so-called Baer-Nunziato model, describes separately each phase by its own density, velocity and pressure. The two phases are coupled by non-conservative terms due to gradients of the void fractions and by source terms for mechanical relaxation, drag force and mass transfer. With appropriate closure laws, it has been proved [2] that this model complies with all the expected physical requirements: positivity of densities and temperatures, maximum principle for the void fraction, conservation of the mixture quantities, decrease of the global entropy… On the basis of this model, it is possible to derive simpler models, which can be used where the flow is still, see [3]. From the numerical point of view, we develop new Finite Volume schemes in [4], which also satisfy the requirements mentioned above. Since they are based on a partial linearization of the physical

  6. Advanced Neutron Source Reactor (ANSR) phenomena identification and ranking (PIR) for large break loss of coolant accidents (LBLOCA)

    Energy Technology Data Exchange (ETDEWEB)

    Ruggles, A. E. [Oak Ridge National Lab., TN (United States); Tennessee Univ., Knoxville, TN (United States); Cheng, L. Y. [Brookhaven National Lab., Upton, NY (United States); Dimenna, R. A. [Westinghouse Savannah River Co., Aiken, SC (United States); Griffith, P. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Wilson, G. E. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1994-06-01

    A team of experts in reactor analysis conducted a phenomena identification and ranking (PIR) exercise for a large break loss-of-coolant accident (LBLOCA) in the Advanced Neutron source Reactor (ANSR). The LBLOCA transient is broken into two separate parts for the PIR exercise. The first part considers the initial depressurization of the system that follows the opening of the break. The second part of the transient includes long-term decay heat removal after the reactor is shut down and the system is depressurized. A PIR is developed for each part of the LBLOCA. The ranking results are reviewed to establish if models in the RELAP5-MOD3 thermalhydraulic code are adequate for use in ANSR LBLOCA simulations. Deficiencies in the RELAP5-MOD3 code are identified and existing data or models are recommended to improve the code for this application. Experiments were also suggested to establish models for situations judged to be beyond current knowledge. The applicability of the ANSR PIR results is reviewed for the entire set of transients important to the ANSR safety analysis.

  7. A study on nonlinear behavior of reactor containment structures during ultimate accident condition(I)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Hoon; Kim, Young Jin; Park, Joo Yeon [Youngdong Univ., Yeongdong (Korea, Republic of)] (and others)

    2003-03-15

    In this study, the following scope and contents are established for first year's study of determining ultimate pressure capacity of CANDU-type reactor containment. State-of-arts on the prediction of the ultimate pressure capacity of prestressed concrete reactor containment. Comparative study on structural characteristics and analysis model of CANDU-type reactor containment. State-of-arts on evaluation method of the ultimate pressure capacity of prestressed concrete reactor containment. Enhancement of evaluation method of the ultimate pressure capacity for PWR containment structure. In order to determine a realistic lower bound of a typical reactor containment structural capacity for internal pressure, modelling techniques and analytical investigation to predict its non-linear behavior up to ultimate capacity are required. Especially, the in-depth evaluation of modeling technique and analysis procedure for determining ultimate pressure capacity of CANDU-type reactor containment is required. Therefore, modelling techniques and analytical investigation to predict its non-linear behavior up to ultimate pressure capacity of CANDU-type reactor containment for internal pressure will be suggested in this study.

  8. Analysis of the rotation accident of assemblies in boiling water reactors; Analisis del accidente de rotacion de ensambles en reactores de agua en ebullicion

    Energy Technology Data Exchange (ETDEWEB)

    Becerril-Gonzalez M, J. J. [Universidad Autonoma de Yucatan, Av. Industrias no contaminantes por Anillo Periferico Norte s/n, Apdo. Postal 150 Cordemex, Merida, Yucatan (Mexico); Fuentes M, L.; Castillo M, J. A.; Ortiz S, J. J.; Perusquia de Cueto, R., E-mail: juanjosebecerril_1@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    For this work was analyzed the impact that would cause the load of a rotated fuel assembly in the behaviour of the core in the Cycle 14 of the Unit 1 of the nuclear power plant of Laguna Verde. To carry out this analysis the code Simulate-3 was used, with which was possible to analyze the behavior of the effective multiplication factor and the thermal limits (MAPRAT, MFLPD and MFLCPR). The rotation of fuel assemblies to 90, 180 and 270 grades was analyzed with regard to the design position, with 0, 1, 2 and 3 burnt cycles for these assemblies. The results show that the thermal limits remain inside the allowed values, therefore if this accident type happened the reactor could continue operating in a sure way. (Author)

  9. Risk Analysis for Public Consumption: Media Coverage of the Ginna Nuclear Reactor Accident.

    Science.gov (United States)

    Dunwoody, Sharon; And Others

    Researchers have determined that the lay public makes risk judgments in ways that are very different from those advocated by scientists. Noting that these differences have caused considerable concern among those who promote and regulate health and safety, a study examined media coverage of the accident at the Robert E. Ginna nuclear power plant…

  10. Study of safety features and accident scenarios in a fusion DEMO reactor

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, M., E-mail: nakamura.makoto@jaea.go.jp [Japan Atomic Energy Agency, Rokkasho, Aomori 039-3212 (Japan); Tobita, K. [Japan Atomic Energy Agency, Rokkasho, Aomori 039-3212 (Japan); Gulden, W. [Fusion for Energy, c/o EFDA Garching and Max-Plank-Institut fuer Plasmaphysik, Garching D-85748 (Germany); Watanabe, K. [Japan Atomic Energy Agency, Rokkasho, Aomori 039-3212 (Japan); Toshiba Corporation, Yokohama, Kanagawa 235-8523 (Japan); Someya, Y. [Japan Atomic Energy Agency, Rokkasho, Aomori 039-3212 (Japan); Tanigawa, H. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Sakamoto, Y. [Japan Atomic Energy Agency, Rokkasho, Aomori 039-3212 (Japan); Araki, T.; Matsumiya, H.; Ishii, K. [Toshiba Corporation, Yokohama, Kanagawa 235-8523 (Japan); Utoh, H. [Japan Atomic Energy Agency, Rokkasho, Aomori 039-3212 (Japan); Takase, H. [IFERC Project Team, Rokkasho, Aomori 039-3212 (Japan); Hayashi, T. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Satou, A.; Yonomoto, T. [Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Federici, G. [Fusion for Energy, c/o EFDA Garching and Max-Plank-Institut fuer Plasmaphysik, Garching D-85748 (Germany); Okano, K. [IFERC Project Team, Rokkasho, Aomori 039-3212 (Japan)

    2014-10-15

    Highlights: This paper reports progress in the fusion DEMO safety research conducted under the Broader Approach DEMO Design Activities; Hazards of a reference DEMO concept have been assessed; Reference accident event sequences in the reference DEMO in this study have been analyzed based on the master logic diagram (MLD) and the functional failure mode and effect analysis (FFMEA) techniques; Accident events of particular concern in the DEMO have been selected based on the MLD and FFMEA analysis. Abstract: After the Fukushima Dai-ichi nuclear accident, a need for assuring safety of fusion energy has grown in the Japanese (JA) fusion research community. DEMO safety research has been launched as a part of Broader Approach DEMO Design Activities (BA-DDA). This paper reports progress in the fusion DEMO safety research conducted under BA-DDA. Safety requirements and evaluation guidelines have been, first of all, established based on those established in the Japanese ITER site invitation activities. The radioactive source terms and energies that can mobilize such source terms have been assessed for a reference DEMO concept. This concept employs in-vessel components that are cooled by pressurized water and built of a low activation ferritic steel (F82H), contains solid pebble beds made of lithium-titanate (Li{sub 2}TiO{sub 3}) and beryllium–titanium (Be{sub 12}Ti) for tritium breeding and neutron multiplication, respectively. It is shown that unlike the energies expected in ITER, the enthalpy in the first wall/blanket cooling loops is large compared to the other energies expected in the reference DEMO concept. Reference accident event sequences in the reference DEMO in this study have been analyzed based on the Master Logic Diagram and Functional Failure Mode and Effect Analysis techniques. Accident events of particular concern in the DEMO have been selected based on the event sequence analysis and the hazard assessment.

  11. Report on Reactor Physics Assessment of Candidate Accident Tolerant Fuel Cladding Materials in LWRs

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Jeffrey J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); George, Nathan [Univ. of Tennessee, Knoxville, TN (United States); Maldonado, G. Ivan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Worrall, Andrew [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-08-28

    This work focuses on ATF concepts being researched at Oak Ridge National Laboratory (ORNL), expanding on previous studies of using alternate cladding materials in pressurized water reactors (PWRs). The neutronic performance of two leading alternate cladding materials were assessed in boiling water reactors (BWRs): iron-chromium-aluminum (FeCrAl) cladding, and silicon carbide (SiC)-based composite cladding. This report fulfills ORNL Milestone M3FT-15OR0202332 within the fiscal year 2015 (FY15)

  12. Reactors

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1988-01-01

    This standard applies to the following types of reactors: shunt reactors, current-limiting reactors including neutral-earthing reactors, damping reactors, tuning (filter) reactors, earthing transformers (neutral couplers), arc-suppression reactors, smoothing reactors, with the exception of the following reactors: small reactors with a rating generally less than 2 kvar single-phase and 10 kvar three-phase, reactors for special purposes such as high-frequency line traps or reactors mounted on rolling stock.

  13. Radiation safety: what can happen in an accident.

    Science.gov (United States)

    Scully, C; de Almeida, O P

    1992-04-11

    Radiation hazards in dental practice have long been recognized, and the dangers from ionising radiation during dental radiography are discussed elsewhere. Continuing legislation will undoubtedly help reduce the risk of over-exposure and accidents. Nevertheless, it is of some concern that radiation safety is still ignored by some: for example, one recent survey in the UK showed that not all radiography sets conformed to modern safety standards. However, the profession also has reason to be concerned about more public radiation hazards that may affect them, and their families and others, and may, without denying the importance of dental radiation protection, have far greater effects on health. Well-known examples of domestic radon exposure occurred in the UK, particularly in the Lake District and the South West, and the nuclear reactor accidents--notably at Chernobyl in 1986.

  14. ROSA-III base test series for a large break loss-of-coolant accident in a boiling water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Tasaka, K.; Abe, N.; Anoda, Y.; Koizumi, Y.; Shiba, M.

    1982-05-01

    The rig of safety assessment (ROSA)-III facility is a volumetrically scaled (1/424) boiling water reactor (BWR) system with an electrically heated core designed for integral loss-of-coolant accident (LOCA) and emergency core cooling system (ECCS) tests. It is confirmed from the experimental results obtained so far that the ROSA-III test facility can simulate major aspects of a BWR LOCA, such as boiling transition by lowering of the mixture level in the core, rewetting by the lower plenum flashing, and final quenching by the ECCS. The overall agreement between the calculated results by the RELAP5/ MOD0 code and the experimental results is good; however, the calculated lower plenum flashing rewetted the whole core and the calculated cladding temperature considerably underpredicts the measured value at the upper part of the core.

  15. TRAC laboratory monitoring of Chernobyl radioactive debris

    Energy Technology Data Exchange (ETDEWEB)

    Sigg, R.A.

    1986-06-09

    A severe accident occurred at the Chernobyl nuclear power plant number 4 in the Soviet Union on April 25, 1986. An explosion released large amounts of radioactive debris, primarily fission products, to the atmosphere. As winds carried debris from the Soviet Union, scientists in Europe and the United States reported detecting fission product activities in air samples. Monitoring by the Tracking Radioactive Atmospheric Contaminants (TRAC) mobile laboratory showed concentrations in the Southeastern United States were well below those considered hazardous. This document provides details of this monitoring effort.

  16. Accident source terms for boiling water reactors with high burnup cores.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O.; Powers, Dana Auburn; Leonard, Mark Thomas

    2007-11-01

    The primary objective of this report is to provide the technical basis for development of recommendations for updates to the NUREG-1465 Source Term for BWRs that will extend its applicability to accidents involving high burnup (HBU) cores. However, a secondary objective is to re-examine the fundamental characteristics of the prescription for fission product release to containment described by NUREG-1465. This secondary objective is motivated by an interest to understand the extent to which research into the release and behaviors of radionuclides under accident conditions has altered best-estimate calculations of the integral response of BWRs to severe core damage sequences and the resulting radiological source terms to containment. This report, therefore, documents specific results of fission product source term analyses that will form the basis for the HBU supplement to NUREG-1465. However, commentary is also provided on observed differences between the composite results of the source term calculations performed here and those reflected NUREG-1465 itself.

  17. Core burnup calculation and accidents analyses of a pressurized water reactor partially loaded with rock-like oxide fuel

    Science.gov (United States)

    Akie, H.; Sugo, Y.; Okawa, R.

    2003-06-01

    A rock-like oxide (ROX) fuel - light water reactor (LWR) burning system has been studied for efficient plutonium transmutation. For the improvement of small negative reactivity coefficients and severe transient behaviors of ROX fueled LWRs, a partial loading core of ROX fuel assemblies with conventional UO 2 assemblies was considered. As a result, although the reactivity coefficients could be improved, the power peaking tends to be large in this heterogeneous core configuration. The reactivity initiated accident (RIA) and loss of coolant accident (LOCA) behaviors were not sufficiently improved. In order to reduce the power peaking, the fuel composition and the assembly design of the ROX fuel were modified. Firstly, erbium burnable poison was added as Er 2O 3 in the ROX fuel to reduce the burnup reactivity swing. Then pin-by-pin Pu enrichment and Er content distributions within the ROX fuel assembly were considered. In addition, the Er content distribution was also considered in the axial direction of the ROX fuel pin. With these modifications, a power peaking factor even lower than the one in a conventional UO 2 fueled core can be obtained. The RIA and LOCA analyses of the modified core have also shown the comparable transient behaviors of ROX partial loading core to those of the UO 2 core.

  18. Modeling in fast dynamics of accidents in the primary circuit of PWR type reactors; Modelisation en dynamique rapide d'accidents dans le circuit primaire des reacteurs a eau pressurisee

    Energy Technology Data Exchange (ETDEWEB)

    Robbe, M.F

    2003-12-01

    Two kinds of accidents, liable to occur in the primary circuit of a Pressurized Water Reactor and involving fast dynamic phenomena, are analyzed. The Loss Of Coolant Accident (LOCA) is the accident used to define the current PWR. It consists in a large-size break located in a pipe of the primary circuit. A blowdown wave propagates through the circuit. The pressure differences between the different zones of the reactor induce high stresses in the structures of the lower head and may degrade the reactor core. The primary circuit starts emptying from the break opening. Pressure decreases very quickly, involving a large steaming. Two thermal-hydraulic simulations of the blowdown phase of a LOCA are computed with the Europlexus code. The primary circuit is represented by a pipe-model including the hydraulic peculiarities of the circuit. The main differences between both computations concern the kind of reactor, the break location and model, and the initialization of the accidental operation. Steam explosion is a hypothetical severe accident liable to happen after a core melting. The molten part of the core (called corium) falls in the lower part of the reactor. The interaction between the hot corium and the cold water remaining at the bottom of the vessel induces a massive and violent vaporization of water, similar to an explosive phenomenon. A shock wave propagates in the vessel. what can damage seriously the neighbouring structures or drill the vessel. This work presents a synthesis of in-vessel parametrical studies carried out with the Europlexus code, the linkage of the thermal-hydraulic code Mc3d dedicated to the pre-mixing phase with the Europlexus code dealing with the explosion, and finally a benchmark between the Cigalon and Europlexus codes relative to the Vulcano mock-up. (author)

  19. Alloy Selection for Accident Tolerant Fuel Cladding in Commercial Light Water Reactors

    Science.gov (United States)

    Rebak, Raul B.

    2015-12-01

    As a consequence of the March 2011 events at the Fukushima site, the U.S. congress asked the Department of Energy (DOE) to concentrate efforts on the development of nuclear fuels with enhanced accident tolerance. The new fuels had to maintain or improve the performance of current UO2-zirconium alloy rods during normal operation conditions and tolerate the loss of active cooling in the core for a considerably longer time period than the current system. DOE is funding cost-shared research to investigate the behavior of advanced steels both under normal operation conditions in high-temperature water [ e.g., 561 K (288 °C)] and under accident conditions for reaction with superheated steam. Current results show that, under accident conditions, the advanced ferritic steels (1) have orders of magnitude lower reactivity with steam, (2) would generate less hydrogen and heat than the current zirconium alloys, (3) are resistant to stress corrosion cracking under normal operation conditions, and (4) have low general corrosion in water at 561 K (288 °C).

  20. The reactor accident in Fukushima Daiichi. The consequence of design deficiencies and inadequate safety engineering; Der Reaktorunfall in Fukushima Daiichi. Folge fehlerhafter Auslegung und unzureichender Sicherheitstechnik

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-03-15

    The reactor accident in Fukushima Daiichi is discussed in the frame of design deficiencies and inadequate safety engineering. The progress of the accident as consequence of the earthquake and the tsunami is described. The radiological situation for the public is supposed to be blow the dose limit of 20 mSv/year. The WHO and UNSCEAR (United Nations Scientific Committee on the Effects of Atomic radiation) did not observe acute radiation injuries. The Japanese authorities have classified the accident to 7 of the INES scale. The German Atomforum e.V. considers the safety engineering of German NPPs to be superior to the Japanese situation due to higher emergency energy supply, extensive measures to reduce the hydrogen accumulation and mitigating measures for the accident management. German NPPS are considered highly robust as the EU stress tests have shown.

  1. COMPARATIVE ANALYSIS OF SOME HEALTH INDICATORS OF VARIOUS RADIATION ACCIDENTS LIQUIDATORS

    Directory of Open Access Journals (Sweden)

    V. M. Shubik

    2010-01-01

    Full Text Available The article presents the results of comparative investigation of morbidity and immunity of liquidators of radiation accidents occurred in South Urals (Kyshtym accident, at Chernobyl NPP and nuclear submarines (NS consequences. The most evident immunity and health changes were revealed for liquidators of Chernobyl NPP accident (ChNPP. Investigations of Kyshtym accident liquidators revealed long-term immunological losses. Comparison of health indicators of Chernobyl and nuclear submarine accident liquidators reveals the possibility of combined influence of radiation and stress on the immunity and health.

  2. Accident Analyses for Conversion of the University of Missouri Research Reactor (MURR) from Highly-Enriched to Low-Enriched Uranium

    Energy Technology Data Exchange (ETDEWEB)

    Stillman, J. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Div., Research and Test Reactor Dept.; Feldman, E. E. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Div., Research and Test Reactor Dept.; Wilson, E. H. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Div., Research and Test Reactor Dept.; Foyto, L. P. [Univ. of Missouri, Columbia, MO (United States). Research Reactor; Kutikkad, K. [Univ. of Missouri, Columbia, MO (United States). Research Reactor; McKibben, J. C. [Univ. of Missouri, Columbia, MO (United States). Research Reactor; Peters, N. J. [Univ. of Missouri, Columbia, MO (United States). Research Reactor; Cowherd, W. M. [Univ. of Missouri, Columbia, MO (United States). College of Engineering, Nuclear Engineering Program; Rickman, B. [Univ. of Missouri, Columbia, MO (United States). College of Engineering, Nuclear Engineering Program

    2014-12-01

    This report contains the results of reactor accident analyses for the University of Missouri Research Reactor (MURR). The calculations were performed as part of the conversion from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members of the Global Threat Reduction Initiative (GTRI) Reactor Conversion Program at the Argonne National Laboratory (ANL), the MURR Facility, and the Nuclear Engineering Program – College of Engineering, University of Missouri-Columbia. The core conversion to LEU is being performed with financial support from the U. S. government. This report contains the results of reactor accident analyses for the University of Missouri Research Reactor (MURR). The calculations were performed as part of the conversion from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members of the Global Threat Reduction Initiative (GTRI) Reactor Conversion Program at the Argonne National Laboratory (ANL), the MURR Facility, and the Nuclear Engineering Program – College of Engineering, University of Missouri-Columbia. The core conversion to LEU is being performed with financial support from the U. S. government. In the framework of non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context most research and test reactors, both domestic and international, have started a program of conversion to the use of LEU fuel. A new type of LEU fuel based on an alloy of uranium and molybdenum (U-Mo) is expected to allow the conversion of U.S. domestic high performance reactors like MURR. This report presents the results of a study of core behavior under a set of accident conditions for MURR cores fueled with HEU U-Alx dispersion fuel or LEU monolithic U-Mo alloy fuel with 10 wt% Mo

  3. Numerical analysis of grid plate melting after a severe accident in a Fast-Breeder Reactor (FBR)

    Indian Academy of Sciences (India)

    A Jasmin Sudha; K Velusamy

    2013-12-01

    Fast breeder reactors (FBRs) are provided with redundant and diverse plant protection systems with a very low failure probability (<10-6/reactor year), making core disruptive accident (CDA), a beyond design basis event (BDBE). Nevertheless, safety analysis is carried out even for such events with a view to mitigate their consequences by providing engineered safeguards like the in-vessel core catcher. During a CDA, a significant fraction of the hot molten fuel moves downwards and gets relocated to the lower plate of grid plate. The ability of this plate to resist or delay relocation of core melt further has been investigated by developing appropriate mathematical models and translating them into a computer code HEATRAN-1. The core melt is a time dependent volumetric heat source because of the radioactive decay of the fission products which it contains. The code solves the nonlinear heat conduction equation including phase change. The analysis reveals that if the bottom of grid plate is considered to be adiabatic, melt-through of grid plate (i.e., melting of the entire thickness of the plate) occurs between 800 s and 1000 s depending upon the initial conditions. Knowledge of this time estimate is essential for defining the initial thermal load on the core catcher plate. If heat transfer from the bottom of grid plate to the underlying sodium is taken into account, then melt-through does not take place, but the temperature of grid plate is high enough to cause creep failure.

  4. Thermal hydraulic analysis of reactivity accidents in MTR research reactors using RELAP5

    Energy Technology Data Exchange (ETDEWEB)

    El-Sahlamy, N.; Khedr, A. [Nuclear and Radiological Regulatory Authority (NRRA), Cairo (Egypt); D' Auria, F.D. [Pisa Univ. (Italy). Facolta di Ingegneria

    2015-12-15

    The present paper comes in the line with the international approach which use the best estimate codes, instead of conservative codes, to get more realistic prediction of system behavior under off-normal reactor conditions. The aim of the current work is to apply this approach using the thermal-hydraulic system code RELAP5/Mod3.3 in a reassessment of safety of the IAEA benchmark 10 MW Research Reactor. The assessment is performed for both slow and fast reactivity insertion transients at initial power of 1.0 W. The reactor power is calculated using the RELA5 point kinetic model. The reactivity feedback terms are considered in two steps. In the first step the feedback from changes in water density and fuel temperature (Doppler effects) are considered. In the second step the feedback from the water temperature changes is added. The results from the first step are compared with that published in IAEA-TECDOC-643 benchmarks. The comparison shows that RELAP5 over predicts the peak power and consequently the fuel, clad and coolant temperatures in case of fast reactivity insertion. The results from the second step show unjustified values for reactor power. Therefore, the model of reactivity feedback from water temperature changes in the RELAP5 code may have to be reviewed.

  5. SCDAP/RELAP5/MOD 3.1 code manual: MATPRO, A library of materials properties for Light-Water-Reactor accident analysis. Volume 4

    Energy Technology Data Exchange (ETDEWEB)

    Hagrman, D.T. [ed.; Allison, C.M.; Berna, G.A. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)] [and others

    1995-06-01

    The SCDAP/RELAP5 code has been developed for best estimate transient simulation of light -- water-reactor coolant systems during a severe accident. The code models the coupled behavior of the reactor coolant system, the core, fission products released during a severe accident transient as well as large and small break loss of coolant accidents, operational transients such as anticipated transient without SCRAM, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling approach is used that permits as much of a particular system to be modeled as necessary. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater conditioning systems. This volume, Volume IV, describes the material properties correlations and computer subroutines (MATPRO) used by SCDAP/RELAP5. formulation of the materials properties are generally semi-empirical in nature. The materials property subroutines contained in this document are for uranium, uranium dioxide, mixed uranium-plutonium dioxide fuel, zircaloy cladding, zirconium dioxide, stainless steel, stainless steel oxide, silver-indium-cadmium alloy, cadmium, boron carbide, Inconel 718, zirconium-uranium-oxygen melts, fill gas mixtures, carbon steel, and tungsten. This document also contains descriptions of the reaction and solution rate models needed to analyze a reactor accident.

  6. Design analysis of the molten core confinement within the reactor vessel in the case of severe accidents at nuclear power plants equipped with a reactor of the VVER type

    Science.gov (United States)

    Zvonaryov, Yu. A.; Budaev, M. A.; Volchek, A. M.; Gorbaev, V. A.; Zagryazkin, V. N.; Kiselyov, N. P.; Kobzar', V. L.; Konobeev, A. V.; Tsurikov, D. F.

    2013-12-01

    The present paper reports the results of the preliminary design estimate of the behavior of the core melt in vessels of reactors of the VVER-600 and VVER-1300 types (a standard optimized and informative nuclear power unit based on VVER technology—VVER TOI) in the case of beyond-design-basis severe accidents. The basic processes determining the state of the core melt in the reactor vessel are analyzed. The concept of molten core confinement within the vessel based on the idea of outside cooling is discussed. Basic assumptions and models, as well as the results of calculation of the interaction between molten materials of the core and the wall of the reactor vessel performed by means of the SOCRAT severe accident code, are presented and discussed. On the basis of the data obtained, the requirements on the operation of the safety systems are determined, upon the fulfillment of which there will appear potential prerequisites for implementing the concept of the confinement of the core melt within the reactor in cases of severe accidents at nuclear power plants equipped with VVER reactors.

  7. Interactive Rapid Dose Assessment Model (IRDAM): reactor-accident assessment methods. Vol. 2

    Energy Technology Data Exchange (ETDEWEB)

    Poeton, R.W.; Moeller, M.P.; Laughlin, G.J.; Desrosiers, A.E.

    1983-05-01

    As part of the continuing emphasis on emergency preparedness, the US Nuclear Regulatory Commission (NRC) sponsored the development of a rapid dose assessment system by Pacific Northwest Laboratory (PNL). This system, the Interactive Rapid Dose Assessment Model (IRDAM) is a micro-computer based program for rapidly assessing the radiological impact of accidents at nuclear power plants. This document describes the technical bases for IRDAM including methods, models and assumptions used in calculations. IRDAM calculates whole body (5-cm depth) and infant thyroid doses at six fixed downwind distances between 500 and 20,000 meters. Radionuclides considered primarily consist of noble gases and radioiodines. In order to provide a rapid assessment capability consistent with the capacity of the Osborne-1 computer, certain simplifying approximations and assumptions are made. These are described, along with default values (assumptions used in the absence of specific input) in the text of this document. Two companion volumes to this one provide additional information on IRDAM. The user's Guide (NUREG/CR-3012, Volume 1) describes the setup and operation of equipment necessary to run IRDAM. Scenarios for Comparing Dose Assessment Models (NUREG/CR-3012, Volume 3) provides the results of calculations made by IRDAM and other models for specific accident scenarios.

  8. CDF modeling of flow and transport processes in the reactor core of a modular high temperature reactor during an air ingress accident; CFD-Modellierung der Stroemungs- und Transportprozesse im Reaktorkern eines modularen Hochtemperaturreaktors waehrend eines Lufteinbruchstoerfalls

    Energy Technology Data Exchange (ETDEWEB)

    Baggemann, Johannes

    2015-05-22

    Generation IV of reactor design is supposed to include inherent safety systems that allow accident management using passive processes (without external energy). The VTR (very high temperature reactor) is graphite moderated with helium cooling. The design concept assumes that in any operational situation the after heat is removed by thermal conduction and radiation. Air ingress is beyond-design accident assuming a leak in the primary circuit triggering oxygen reaction with the hot graphite that could damage the barriers for fission product release. Using 3D CFD (computational fluid dynamics) codes the air ingress scenario is simulated, the flow and transport processes in the reactor core are analyzed. For validation of the modeling heat transport processes were investigated in specific test facilities.

  9. Small-break loss-of-coolant accidents in the updated PIUS 600 advanced reactor design

    Energy Technology Data Exchange (ETDEWEB)

    Boyack, B.E.; Steiner, J.L.; Harmony, S.C. [Los Alamos National Lab., Albuquerque, NM (United States)] [and others

    1995-09-01

    The PIUS advanced reactor is a 640-MWe pressurized water reactor developed by Asea Brown Boveri (ABB). A unique feature of the PIUS concept is the absence of mechanical control and shutdown rods. Reactivity is normally controlled by coolant boron concentration and the temperature of the moderator coolant. ABB submitted the PIUS design to the US Nuclear Regulatory Commission (NRC) for preapplication review, and Los Alamos supported the NRC`s review effort. Baseline analyses of small-break initiators at two locations were performed with the system neutronic and thermal-hydraulic analysis code TRAC-PF1/MOD2. In addition, sensitivity studies were performed to explore the robustness of the PIUS concept to severe off-normal conditions having a very low probability of occurrence.

  10. R and D relative to the serious accidents in the PWR type reactors: assessment and perspectives; R and D relative aux accidents graves dans les reacteurs a eau pressurisee: bilan et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Bentaib, A.; Bonneville, H.; Caroli, H.; Chaumont, B.; Clement, B.; Cranga, M.; Koundy, V.; Laurent, B.; Micaelli, J.C.; Meignen, R.; Pichereau, F.; Plassart, D.; Van-Dorsselaere, P. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Clamart (France); Ducros, G.; Journeau, Ch.; Magallon, D. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Durin, M.; Studer, E. [CEA Saclay 91 - Gif sur Yvette (France); Seiler, J.M. [CEA Grenoble, 38 (France); Ranval, W. [Electricite de France (EDF), 75 - Paris (France)

    2006-07-01

    This document presents the current state of the research relative to the grave accidents realized in France and abroad. It aims at giving the most exhaustive possible and objective vision of this original field of research. He allows to contribute to the identification and to the hierarchical organization of the needs of R and D, this hierarchical organization in front of, naturally, to be completed by a strong lighting on needs in terms of safety analyses associated with the different risks and the physical phenomena, in particular with the support of probability evaluations of safety level 2, whose the level of sharpness must be sufficient not to hide, by construction, physical phenomena of which the limited knowledge leads to important uncertainties. Let us note that neither the safety analyses, nor the E.P.S. 2 are presented in this document. This report presents the physical phenomena which can arise during a grave accident, in the reactor vessel and in the reactor containment, their chain and the means allowing to ease the effects. The corresponding scenarios are presented to the chapter 2. The chapter 3 is dedicated to the progress of the accident in the reactor vessel; the degradation of the core in reactor vessel (3.1), the behavior of the corium in bottom of reactor vessel (3.2) the break of the reactor vessel (3.3) and the fusion in pressure (3.4) are thus handled there. The chapter 4 concerns the phenomena which can lead to a premature failure of the containment, namely the direct heating of gases of the containment (4.1), the hydrogen risk (4.2) and the vapor explosion (4.3). The phenomenon which can lead to a delayed failure from the containment, namely the interaction corium-concrete, is approached on the chapter 5. The chapter 6 is dedicated to the problems connected to the keeping back and to the corium cooling in reactor vessel and out of reactor vessel, namely the keeping back in reactor vessel by re-flooding of the primary circuit or by re

  11. Micro-analytical uranium isotope and chemical investigations of zircon crystals from the Chernobyl “lava” and their nuclear fuel inclusions

    Energy Technology Data Exchange (ETDEWEB)

    Pöml, P., E-mail: Philipp.POEML@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Burakov, B. [Laboratory of Applied Mineralogy and Radiogeochemistry, V.G. Khlopin Radium Institute, 28, 2-nd Murinskiy Ave., St. Petersburg 194021 (Russian Federation); Geisler, T. [Steinmann Institut für Geologie, Mineralogie und Paläontologie, University of Bonn, Poppelsdorfer Schloss, 53115 Bonn (Germany); Walker, C.T. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Grange, M.L.; Nemchin, A.A. [Department of Applied Geology, Western Australian School of Mines, Curtin University, GPO Box U1987, Western Australia 6845 (Australia); Berndt, J. [Institut für Mineralogie, Westfälische Wilhelms-Universität, Corrensstraße 24, 48149 Münster (Germany); Fonseca, R.O.C. [Steinmann Institut für Geologie, Mineralogie und Paläontologie, University of Bonn, Poppelsdorfer Schloss, 53115 Bonn (Germany); Bottomley, P.D.W.; Hasnaoui, R. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany)

    2013-08-15

    U isotope data measured on real fragments of the Chernobyl nuclear fuel included in zircon crystals crystallised from the Chernobyl “lava” are presented for the first time. The U isotope data show no anomalies and lie within the expected burnup values for the Chernobyl nuclear fuel. However, the U concentration, the U isotopic composition, and the Ti concentration in the host zircon vary significantly within single crystals as well as between single crystals. Our results indicate that during the time of melt activity temperature and melt composition likely varied considerably. New melt was formed progressively (and solidified) during the accident that reacted and mixed with pre-existing melt that never fully equilibrated. In such an environment zircon crystals crystallised at temperatures below 1250 °C, as estimated from thermodynamic considerations along with the observation that the centre of the investigated zircon crystal contains monoclinic ZrO{sub 2} inclusions. Since the zircon crystals crystallised before the silicate melt spread out into the reactor block basement, the flow of the melt into the basement must also have occurred at temperatures below 1250 °C.

  12. The Chernobyl reactor accident, ten years on. Teaching projects for mathematics instruction in interdisciplinary working groups; 10 Jahre nach Tschernobyl. Unterrichtsprojekte fuer den Mathematikunterricht in faecheruebergreifenden Kooperationen

    Energy Technology Data Exchange (ETDEWEB)

    Boer, H. [comp.; Delle, E. [comp.; Mies, K. [comp.; Warmeling, A. [comp.

    1996-10-01

    The booklet presents background information and addresses the following aspects: ionizing radiation and radiation effects; safety of German nuclear power plants; statistical evidence of radiation injuries; short-lived and long-lived ionizing radiation; radioactive waste; CO{sub 2} emissions as an argument in favour of nuclear power generation. The material presented is intended for use by a school project team interested in the subjects, or as a basis for collaborative, interdisciplinary teaching in working groups, and it offers information and problems for mathematics teaching. (HP) [Deutsch] Neben vielen Informationen behandelt die Broschuere: Strahlen und Strahlenwirkungen; Sicherheit deutscher Kernkraftwerke; statistischer Nachweis von Strahlenschaeden; Kurz- und Langfestigkeit der Strahlenbelastung; radioaktiver Abfall; CO{sub 2}-Problematik als Argument fuer die Kernenergie. Die Broschuere ist gedacht z.B. fuer eine Projektgruppe, einen Projekttag, fuer eine Lerngruppe in faecheruebergreifender Kooperation. Die Materialien sind ausgearbeitet fuer die Themembearbeitung im Mathematikunterricht mit Uebungsaufgaben. (HP)

  13. Mental health consequences of the Chernobyl disaster.

    Science.gov (United States)

    Bromet, Evelyn J

    2012-03-01

    The psychosocial consequences of disasters have been studied for more than 100 years. The most common mental health consequences are depression, anxiety, post-traumatic stress disorder, medically unexplained somatic symptoms, and stigma. The excess morbidity rate of psychiatric disorders in the first year after a disaster is in the order of 20%. Disasters involving radiation are particularly pernicious because the exposure is invisible and universally dreaded, and can pose a long-term threat to health. After the Chernobyl disaster, studies of clean-up workers (liquidators) and adults from contaminated areas found a two-fold increase in post-traumatic stress and other mood and anxiety disorders and significantly poorer subjective ratings of health. Among liquidators, the most important risk factor was severity of exposure. In general population samples, the major risk factor was perceived exposure to harmful levels of radiation. These findings are consistent with results from A-bomb survivors and populations studied after the Three Mile Island nuclear power plant accident. With regard to children, apart from findings from ecological studies that lack direct data on radiation or other teratologic exposures and local studies in Kiev, the epidemiologic evidence suggests that neither radiation exposure nor the stress of growing up in the shadow of the accident was associated with emotional disorders, cognitive dysfunction, or impaired academic performance. Thus, based on the studies of adults, the Chernobyl Forum concluded that mental health was the largest public health problem unleashed by the accident. Since mental health is a leading cause of disability, physical morbidity, and mortality, health monitoring after radiation accidents like Fukushima should include standard measures of well-being. Moreover, given the comorbidity of mental and physical health, the findings support the value of training non-psychiatrist physicians in recognizing and treating common mental

  14. Measurement of airborne fission products in Chapel Hill, NC, USA from the Fukushima I reactor accident

    CERN Document Server

    MacMullin, S; Green, M P; Henning, R; Holmes, R; Vorren, K; Wilkerson, J F

    2011-01-01

    We present measurements of airborne fission products in Chapel Hill, NC, USA, from 62 days following the March 11, 2011, accident at the Fukushima I Nuclear Power Plant. Airborne particle samples were collected daily in air filters and radio-assayed with two high-purity germanium (HPGe) detectors. The fission products I-131 and Cs-137 were measured with maximum activities of 4.2 +/- 0.6 mBq/m^2 and 0.42 +/- 0.07 mBq/m^2 respectively. Additional activity from I-131, I-132, Cs-134, Cs-136, Cs-137 and Te-132 were measured in the same air filters using a low-background HPGe detector at the Kimballton Underground Research Facility (KURF).

  15. Accident Analyses for Conversion of the University of Missouri Research Reactor (MURR) from Highly-Enriched to Low-Enriched Uranium

    Energy Technology Data Exchange (ETDEWEB)

    Stillman, J. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Feldman, E. E. [Argonne National Lab. (ANL), Argonne, IL (United States); Jaluvka, D. [Argonne National Lab. (ANL), Argonne, IL (United States); Wilson, E. H. [Argonne National Lab. (ANL), Argonne, IL (United States); Foyto, L. P. [Univ. of Missouri, Columbia, MO (United States); Kutikkad, K. [Univ. of Missouri, Columbia, MO (United States); McKibben, J. C. [Univ. of Missouri, Columbia, MO (United States); Peters, N. J. [Univ. of Missouri, Columbia, MO (United States)

    2017-02-01

    This report contains the results of reactor accident analyses for the University of Missouri Research Reactor (MURR). The calculations were performed as part of the conversion from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members in the Research and Test Reactor Department at the Argonne National Laboratory (ANL) and the MURR Facility. MURR LEU conversion is part of an overall effort to develop and qualify high-density fuel within the U.S. High Performance Research Reactor Conversion (USHPRR) program conducted by the U.S. Department of Energy National Nuclear Security Administration’s Office of Material Management and Minimization (M3).

  16. Fukushima Accident: Sequence of Events and Lessons Learned

    Science.gov (United States)

    Morse, Edward C.

    2011-10-01

    The Fukushima Dai-Ichi nuclear power station suffered a devastating Richter 9.0 earthquake followed by a 14.0 m tsunami on 11 March 2011. The subsequent loss of power for emergency core cooling systems resulted in damage to the fuel in the cores of three reactors. The relief of pressure from the containment in these three reactors led to sufficient hydrogen gas release to cause explosions in the buildings housing the reactors. There was probably subsequent damage to a spent fuel pool of a fourth reactor caused by debris from one of these explosions. Resultant releases of fission product isotopes in air were significant and have been estimated to be in the 3 . 7 --> 6 . 3 ×1017 Bq range (~10 MCi) for 131I and 137Cs combined, or approximately one tenth that of the Chernobyl accident. A synopsis of the sequence of events leading up to this large release of radioactivity will be presented, along with likely scenarios for stabilization and site cleanup in the future. Some aspects of the isotope monitoring programs, both locally and at large, will also be discussed. An assessment of radiological health risk for the plant workers as well as the general public will also be presented. Finally, the impact of this accident on design and deployment of nuclear generating stations in the future will be discussed.

  17. Advanced computational methods for the assessment of reactor core behaviour during reactivity initiated accidents. Final report; Fortschrittliche Rechenmethoden zum Kernverhalten bei Reaktivitaetsstoerfaellen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Pautz, A.; Perin, Y.; Pasichnyk, I.; Velkov, K.; Zwermann, W.; Seubert, A.; Klein, M.; Gallner, L.; Krzycacz-Hausmann, B.

    2012-05-15

    The document at hand serves as the final report for the reactor safety research project RS1183 ''Advanced Computational Methods for the Assessment of Reactor Core Behavior During Reactivity-Initiated Accidents''. The work performed in the framework of this project was dedicated to the development, validation and application of advanced computational methods for the simulation of transients and accidents of nuclear installations. These simulation tools describe in particular the behavior of the reactor core (with respect to neutronics, thermal-hydraulics and thermal mechanics) at a very high level of detail. The overall goal of this project was the deployment of a modern nuclear computational chain which provides, besides advanced 3D tools for coupled neutronics/ thermal-hydraulics full core calculations, also appropriate tools for the generation of multi-group cross sections and Monte Carlo models for the verification of the individual calculational steps. This computational chain shall primarily be deployed for light water reactors (LWR), but should beyond that also be applicable for innovative reactor concepts. Thus, validation on computational benchmarks and critical experiments was of paramount importance. Finally, appropriate methods for uncertainty and sensitivity analysis were to be integrated into the computational framework, in order to assess and quantify the uncertainties due to insufficient knowledge of data, as well as due to methodological aspects.

  18. Investigation of a hydrogen mitigation system during large break loss-of-coolant accident for a two-loop pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Dehjourian, Mehdi; Rahgoshay, Mohmmad; Jahanfamia, Gholamreza [Dept. of Nuclear Engineering, Science and Research Branch, Islamic Azad University of Tehran, Tehran (Iran, Islamic Republic of); Sayareh, Reza [Faculty of Electrical and Computer Engineering, Kerman Graduate University of Technology, Kerman (Iran, Islamic Republic of); Shirani, Amir Saied [Faculty of Engineering, Shahid Beheshti University, Tehran (Iran, Islamic Republic of)

    2016-10-15

    Hydrogen release during severe accidents poses a serious threat to containment integrity. Mitigating procedures are necessary to prevent global or local explosions, especially in large steel shell containments. The management of hydrogen safety and prevention of over-pressurization could be implemented through a hydrogen reduction system and spray system. During the course of the hypothetical large break loss-of-coolant accident in a nuclear power plant, hydrogen is generated by a reaction between steam and the fuel-cladding inside the reactor pressure vessel and also core concrete interaction after ejection of melt into the cavity. The MELCOR 1.8.6 was used to assess core degradation and containment behavior during the large break loss-of-coolant accident without the actuation of the safety injection system except for accumulators in Beznau nuclear power plant. Also, hydrogen distribution in containment and performance of hydrogen reduction system were investigated.

  19. Root causes and impacts of severe accidents at large nuclear power plants.

    Science.gov (United States)

    Högberg, Lars

    2013-04-01

    The root causes and impacts of three severe accidents at large civilian nuclear power plants are reviewed: the Three Mile Island accident in 1979, the Chernobyl accident in 1986, and the Fukushima Daiichi accident in 2011. Impacts include health effects, evacuation of contaminated areas as well as cost estimates and impacts on energy policies and nuclear safety work in various countries. It is concluded that essential objectives for reactor safety work must be: (1) to prevent accidents from developing into severe core damage, even if they are initiated by very unlikely natural or man-made events, and, recognizing that accidents with severe core damage may nevertheless occur; (2) to prevent large-scale and long-lived ground contamination by limiting releases of radioactive nuclides such as cesium to less than about 100 TBq. To achieve these objectives the importance of maintaining high global standards of safety management and safety culture cannot be emphasized enough. All three severe accidents discussed in this paper had their root causes in system deficiencies indicative of poor safety management and poor safety culture in both the nuclear industry and government authorities.

  20. Air radioactivity levels following the Fukushima reactor accident measured at the Laboratoire Souterrain de Modane, France.

    Science.gov (United States)

    Loaiza, P; Brudanin, V; Piquemal, F; Reyss, J-L; Stekl, I; Warot, G; Zampaolo, M

    2012-12-01

    The radioactivity levels in the air of the radionuclides released by the Fukushima accident were measured at the Laboratoire Souterrain de Modane, in the South-East of France, during the period 25 March-18 April 2011. Air-filters from the ventilation system exposed for one or two days were measured using low-background gamma-ray spectrometry. In this paper we present the activity concentrations obtained for the radionuclides (131)I, (132)Te, (134)Cs, (137)Cs, (95)Nb, (95)Zr, (106)Ru, (140)Ba/La and (103)Ru. The activity concentration of (131)I was of the order of 100 μBq/m(3), more than 100 times higher than the activities of other fission products. The highest activities of (131)I were measured as a first peak on 30 March and a second peak on 3-4 April. The activity concentrations of (134)Cs and (137)Cs varied from 5 to 30 μBq/m(3). The highest activity concentration recorded for Cs corresponded to the same period as for (131)I, with a peak on 2-3 April. The results of the radioactivity concentration levels in grass and mushrooms exposed to the air in the Modane region were also measured. Activity concentrations of (131)I of about 100 mBq/m(2) were found in grass.

  1. Commissioning of the STAR test section for experimental simulation of loss of coolant accident using the EC-208 instrumented fuel assembly of the IEA-R1 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Maprelian, Eduardo; Torres, Walmir M.; Prado, Adelk C.; Umbehaun, Pedro E.; Franca, Renato L.; Santos, Samuel C.; Macedo, Luiz A.; Sabundjian, Gaiane, E-mail: emaprel@ipen.br, E-mail: wmtorres@ipen.br, E-mail: acprado@ipen.br, E-mail: umbehaun@ipen.br, E-mail: rlfranca@ipen.br, E-mail: samuelcs@ipen.br, E-mail: lamacedo@ipen.br, E-mail: gdjian@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SO (Brazil)

    2015-07-01

    The three basic safety functions of Research Reactors (RR) are the safe shutdown of the reactor, the proper cooling of the decay heat of the fuel elements and the confinement of radioactive materials. Compared to Nuclear Power Reactors, RR power release is small, yet its three safety functions must be met to ensure the integrity of the reactor. During a loss of coolant accident (LOCA) in pool type RR, partial or complete loss of pool water may occur, with consequent partial or complete uncovering of the fuel assemblies. In such an accident, the decay heat removal safety function must not be compromised. The Test Section for Experimental Simulation of Loss of Coolant Accident (STAR) is in commissioning phase. This test section will provide experimental data on partial and total uncovering of the EC-208 instrumented fuel assembly (IFA) irradiated in the IEA-R1. Experimental results will be useful in validation of computer codes for RR safety analysis, particularly on heat removal efficiency aspects (safety function) in accident conditions. STAR comprises a base on which is installed the IFA, the cylindrical stainless steel hull, the compressed air system for the test section emptying and refilling, and the instrumentation for temperature and level measurements. The commissioning tests or pre-operational check, consist of several preliminary tests to verify experimental procedures, the difficulties during assembling of STAR in the pool, the difficulties in control the emptying and refilling velocities, as well as, the repeatability capacity, tests of equipment, valves and systems and tests of instrumentation and data acquisition system. Safety, accuracy and easiness of operation will be checked. (author)

  2. A comparison of world-wide uses of severe reactor accident source terms

    Energy Technology Data Exchange (ETDEWEB)

    Ang, M.L. [NNC Ltd., Knutsford (United Kingdom); Frid, W. [Swedish Nuclear Power Inspectorate, Stockholm (Sweden); Kersting, E.J.; Friederichs, H.G. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Koeln (Germany); Lee, R.Y. [Nuclear Regulatory Commission, Washington, DC (United States); Meyer-Heine, A. [CEA Centre d`Etudes de Cadarache, Saint Paul Lez Durance (France); Powers, D.A. [Sandia National Labs., Albuquerque, NM (United States); Soda, K. [Japan Atomic Energy Research Inst., Tokyo (Japan); Sweet, D. [AEA Technology, Winfrith (United Kingdom)

    1994-09-01

    The definitions of source terms to reactor containments and source terms to the environment are discussed. A comparison is made between the TID-14844 example source term and the alternative source term described in NUREG-1465. Comparisons of these source terms to the containments and those used in France, Germany, Japan, Sweden, and the United Kingdom are made. Source terms to the environment calculated in NUREG-1500 and WASH-1400 are discussed. Again, these source terms are compared to those now being used in France, Germany, Japan, Sweden, and the United Kingdom. It is concluded that source terms to the containment suggested in NUREG-1465 are not greatly more conservative than those used in other countries. Technical bases for the source terms are similar. The regulatory use of the current understanding of radionuclide behavior varies among countries.

  3. The noncondensable gas effects on loss-of-coolant accident steam condensation loads in boiling water reactor pressure suppression pool

    Energy Technology Data Exchange (ETDEWEB)

    Kukita, Y.; Namatame, K.; Shiba, M.; Takeshita, I.

    1983-11-01

    The noncondensable gas effects on the loss-ofcoolant-accident-induced steam condensation loads in the boiling water reactor pressure suppression pool have been investigated with regard to experimental data obtained from a large-scale multivent test program. Previous studies have noted that the presence of the noncondensable gas (air), which initially fills the containment drywell space, stabilizes the direct-contact condensation in the pressure suppression pool and hampers onset of the chugging phenomenon, which induces most significant steam condensation load onto the pool boundary. This was found to be true for the tests with relatively small-break diameters, where the maximum steam mass fluxes in the vent pipe were lower than the upper threshold value for the onset of chugging. However, in the tests with the maximum vent steam mass fluxes moderately higher than the chugging upper threshold value, early depletion of the noncondensable gas tended to result in significant stabilization of steam condensation accompanied by an excursion of temperature of pool water surrounding the vent pipe outlets, which led to a delayed onset of chugging. Due to this combined influence of the noncondensable gas and nonuniform pool temperature, and due to dependence of magnitude of chugging load on the vent steam mass flux, the peak magnitude of the steam condensation load appearing in a blowdown can be very sensitive to the initial and break conditions.

  4. 3-dimensional thermohydraulic analysis of KALIMER reactor pool during unprotected accidents

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Bum; Hahn Do Hee

    2003-01-01

    During a normal reactor scram, the heat generation is reduced almost instantaneously while the coolant flow rate follows the pump coastdown. This mismatch between power and flow results in a situation where the core flow entering the hot pool is at a lower temperature than the temperature of the bulk pool sodium. This temperature difference leads to thermal stratification. Thermal stratification can occur in the hot pool region if the entering coolant is colder than the existing hot pool coolant and the flow momentum is not large enough to overcome the negative buoyancy force. Since the fluid of hot pool enters IHXs, the temperature distribution of hot pool can alter the overall system response. Hence, it is necessary to predict the pool coolant temperature distribution with sufficient accuracy to determine the inlet temperature conditions for the IHXs and its contribution to the net buoyancy head. Therefore, two-dimensional hot pool thermohydraulic model named HP2D has been developed. In this report code-to-code comparison analysis between HP2D and COMMIX-1AR/P has been performed in the case of steady-state and UTOP.

  5. Strategies for reactor safety: Preventing loss of coolant accidents. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lydell, B.O.Y. [RSA Technoligies, Vista (United States)

    1997-12-01

    This final report on the NKS/RAK-1.2 summarizes the main features of the PIFRAP PC-program and its intended implementation. Regardless of the preferred technical approach to LOCA frequency estimation, the analysis approach must include recognition of the following technical issues: (a) Degradation and failure mechanisms potentially affecting piping systems within the reactor coolant pressure boundary (RCPB) and the potential consequences; (b) In-service inspection practices and how they influence piping reliability; and (c) The service experience with piping systems. The report consists of six sections and one appendix. A Nordic perspective on LOCA and nuclear safety is given. It includes summaries of results from research in material sciences and current regulatory philosophies regarding piping reliability. A summary of the LOCA concept is applied in Nordic PSA studies. It includes a discussion on deterministic and probabilistic views on LOCA. The R and D on piping reliability by SKI and the PIFRAP model is summarized. Next, Section 6 presents conclusion and recommendations. Finally, Appendix A contains a list of abbreviations and acronyms, together with a glossary of technical terms. (EG) 16 refs.

  6. Analysis of an accident type sbloca in reactor contention AP1000 with 8.0 Gothic code; Analisis de un accidente tipo Sbloca en la contencion del reactor AP1000 con el codigo Gothic 8.0

    Energy Technology Data Exchange (ETDEWEB)

    Goni, Z.; Jimenez Varas, G.; Fernandez, K.; Queral, C.; Montero, J.

    2016-08-01

    The analysis is based on the simulation of a Small Break Loss-of-Coolant-Accident in the AP1000 nuclear reactor using a Gothic 8.0 tri dimensional model created in the Science and Technology Group of Nuclear Fision Advanced Systems of the UPM. The SBLOCA has been simulated with TRACE 5.0 code. The main purpose of this work is the study of the thermo-hydraulic behaviour of the AP1000 containment during a SBLOCA. The transients simulated reveal close results to the realistic behaviour in case of an accident with similar characteristics. The pressure and temperature evolution enables the identification of the accident phases from the RCS point of view. Compared to the licensing calculations included in the AP1000 Safety Analysis, it has been proved that the average pressure and temperature evolution is similar, yet lower than the licensing calculations. However, the temperature and inventory distribution are significantly heterogeneous. (Author)

  7. Contribution of prototypic material tests on the Plinius platform to the study of nuclear reactor severe accident; Contribution des essais en materiaux prototypiques sur la plate-forme Plinius a l'etude des accidents graves de reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Journeau, Ch

    2008-01-15

    The PLINIUS experimental platform at CEA Cadarache is dedicated to the experimental study of nuclear reactor severe accidents thanks to experiments between 2000 and 3500 K with prototypic corium. Corium is the mixture that would be formed by an hypothetical core melting and its mixing with structural materials. Prototypical corium has the same chemical composition as the corium corresponding to a given accident scenario but has a different isotopic composition (use of depleted uranium,...). Research programs and test series have been performed to study corium thermophysical properties, fission product behaviour, corium spreading, solidification and interaction with concrete as well as its coolability. It was the frame of research training of many students and was realized within national, European and international collaborations. (author)

  8. Spatially continuous approach to the description of incoherencies in fast reactor accident analysis

    Energy Technology Data Exchange (ETDEWEB)

    Luck, L B

    1976-12-01

    A generalized cell-type approach is developed in which individual subassemblies are represented as a unit. By appropriate characterization of the results of separate detailed investigations, spatial variations within a cell are represented as a superposition. The advantage of this approach is that costly detailed cell-type information is generated only once or a very few times. Spatial information obtained by the cell treatment is properly condensed in order to drastically reduce the transient computation time. Approximate treatments of transient phenomena are developed based on the use of distributions of volume and reactivity worth with temperature and other reactor parameters. Incoherencies during transient are physically dependent on the detailed variations in the initial state. Therefore, stationary volumetric distributions which contain in condensed form the detailed initial incoherency information provides a proper basis for the transient treatment. Approximate transient volumetric distributions are generated by a suitable transformation of the stationary distribution to reflect the changes in the transient temperature field. Evaluation of transient changes is based on results of conventional uniform channel calculations and a superposition of lateral variations as they are derived from prior cell investigations. Specific formulations are developed for the treatment of reactivity feedback. Doppler and sodium expansion reactivity feedback is related to condensed temperature-worth distributions. Transient evaluation of the worth distribution is based on the relation between stationary and transient volumetric distributions, which contains the condensed temperature field information. Coolant voiding is similarly treated with proper distribution information. Results show that the treatments developed for the transient phase up to and including sodium boiling constitute a fast and effective simulation of inter- and intra-subassembly incoherence effects.

  9. Validation of CONTAIN-LMR code for accident analysis of sodium-cooled fast reactor containments

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, S.; Hering, W.; Schikorr, M.; Stieglitz, R. [Inst. for Neutron Physic and Reactor Technology, Karlsruhe Inst. of Technology, Campus Nord (Germany)

    2012-07-01

    CONTAIN-LMR 1 is an analytical tool for the containment performance of sodium cooled fast reactors. In this code, the modelling for the sodium fire is included: the oxygen diffusion model for the sodium pool fire, and the liquid droplet model for the sodium spray fire. CONTAIN-LMR is also able to model the interaction of liquid sodium with concrete structure. It may be applicable to different concrete compositions. Testing and validation of these models will help to qualify the simulation results. Three experiments with sodium performed in the FAUNA facility at FZK have been used for the validation of CONTAIN-LMR. For pool fire tests, calculations have been performed with two models. The first model consists of one gas cell representing the volume of the burn compartment. The volume of the second model is subdivided into 32 coupled gas cells. The agreement between calculations and experimental data is acceptable. The detailed pool fire model shows less deviation from experiments. In the spray fire, the direct heating from the sodium burning in the media is dominant. Therefore, single cell modeling is enough to describe the phenomena. Calculation results have reasonable agreement with experimental data. Limitations of the implemented spray model can cause the overestimation of predicted pressure and temperature in the cell atmosphere. The ability of the CONTAIN-LMR to simulate the sodium pool fire accompanied by sodium-concrete reactions was tested using the experimental study of sodium-concrete interactions for construction concrete as well as for shielding concrete. The model provides a reasonably good representation of chemical processes during sodium-concrete interaction. The comparison of time-temperature profiles of sodium and concrete shows, that the model requires modifications for predictions of the test results. (authors)

  10. Phenomenology of severe accidents in BWR type reactors. First part; Fenomenologia de accidentes severos en reactores nucleares de agua en ebullicion. Primera parte

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval V, S. [Instituto de Investigaciones Electricas, Gerencia de Energia Nuclear, Av. Reforma 113, Col. Palmira, 62490 Cuernavaca, Morelos (Mexico)

    2003-07-01

    A Severe Accident in a nuclear power plant is a deviation from its normal operating conditions, resulting in substantial damage to the core and, potentially, the release of fission products. Although the occurrence of a Severe Accident on a nuclear power plant is a low probability event, due to the multiple safety systems and strict safety regulations applied since plant design and during operation, Severe Accident Analysis is performed as a safety proactive activity. Nuclear Power Plant Severe Accident Analysis is of great benefit for safety studies, training and accident management, among other applications. This work describes and summarizes some of the most important phenomena in Severe Accident field and briefly illustrates its potential use based on the results of two generic simulations. Equally important and abundant as those here presented, fission product transport and retention phenomena are deferred to a complementary work. (Author)

  11. Termination of light-water reactor core-melt accidents with a chemical core catcher: the core-melt source reduction system (COMSORS)

    Energy Technology Data Exchange (ETDEWEB)

    Forsberg, C.W.; Parker, G.W.; Rudolph, J.C.; Osborne-Lee, I.W. [Oak Ridge National Lab., TN (United States); Kenton, M.A. [Dames and Moore, Westmont, IL (United States)

    1996-09-01

    The Core-Melt Source Reduction System (COMSORS) is a new approach to terminate light-water reactor core melt accidents and ensure containment integrity. A special dissolution glass is placed under the reactor vessel. If core debris is released onto the glass, the glass melts and the debris dissolves into the molten glass, thus creating a homogeneous molten glass. The molten glass, with dissolved core debris, spreads into a wide pool, distributing the heat for removal by radiation to the reactor cavity above or by transfer to water on top of the molten glass. Expected equilibrium glass temperatures are approximately 600 degrees C. The creation of a low-temperature, homogeneous molten glass with known geometry permits cooling of the glass without threatening containment integrity. This report describes the technology, initial experiments to measure key glass properties, and modeling of COMSORS operations.

  12. The Chernobyl experience in the area of retrospective dosimetry.

    Science.gov (United States)

    Chumak, Vadim V

    2012-03-01

    The Chernobyl accident, which occurred on 26 April 1986 at a nuclear power plant located less than 150 km north of Kiev, was the largest nuclear accident to date. The unprecedented scale of the accident was determined not only by the amount of released activity, but also by the number of workers and of the general public involved, and therefore exposed to increased doses of ionising radiation. Due to the unexpected and large scale of the accident, dosimetry techniques and practices were far from the optimum; personal dosimetry of cleanup workers (liquidators) was not complete, and there were no direct measurements of the exposures of members of the public. As a result, an acute need for retrospective dose assessment was dictated by radiation protection and research considerations. In response, substantial efforts have been made to reconstruct doses for the main exposed cohorts, using a broad variety of newly developed methods: analytical, biological and physical (electron paramagnetic resonance spectroscopy of teeth, thermoluminescence of quartz) and modelling. This paper reviews the extensive experience gained by the National Research Center for Radiation Medicine, Academy of Medical Sciences, Ukraine in the field of retrospective dosimetry of large cohorts of exposed population and professionals. These dose reconstruction projects were implemented, in particular, in the framework of epidemiological studies, designed to follow-up the medical consequences of the Chernobyl accident and study health effects of ionizing radiation, particularly Ukrainian-American studies of cataracts and leukaemia among liquidators.

  13. Chernobyl: the facts

    Energy Technology Data Exchange (ETDEWEB)

    Stanbridge, R. (Stockholm Univ. (Sweden) Dept. of Journalism, Media and Communication Studies)

    1993-08-01

    In these Search Strategies, searchers from different countries and professions are given a question to answer, a budget of Pounds 50 and a time in which to produce their report. We hope that these blow-by-blow accounts, together with the hints and tips picked up along the way, will help readers to develop their own search strategies. Journalists are more and more coming to use online services and here the author gives a journalist's account of tracking down the elusive facts surrounding the Chernobyl disaster. (author).

  14. Chernobyl seed project. Advances in the identification of differentially abundant proteins in a radio-contaminated environment

    Directory of Open Access Journals (Sweden)

    Namik Mammad Oglu Rashydov

    2015-07-01

    Full Text Available Plants have the ability to grow and successfully reproduce in radio-contaminated environments, which has been highlighted by nuclear accidents at Chernobyl (1986 and Fukushima (2011. The main aim of this article is to summarize the advances of the Chernobyl seed project which has the purpose to provide proteomic characterization of plants grown in the Chernobyl area. We present a summary of comparative proteomic studies on soybean and flax seeds harvested from radio-contaminated Chernobyl areas during two successive generations. Using experimental design developed for radio-contaminated areas, altered abundances of glycine betaine, seed storage proteins, and proteins associated with carbon assimilation into fatty acids were detected. Similar studies in Fukushima radio-contaminated areas might complement these data. The results from these Chernobyl experiments can be viewed in a user-friendly format at a dedicated web-based database freely available at www.chernobylproteomics.sav.sk.

  15. A model for the analysis of loss of decay heat removal during loss of coolant accident in MTR pool type research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Bousbia-salah, Anis [Dipartimento di Ingegneria Meccanica, Nucleari e della Produzione, Facolta di Ingegneria, Universita di Pisa, Via Diotisalvi, 2, 56126 Pisa (Italy)]. E-mail: b.salah@ing.unipi.it; Meftah, Brahim [Division Reacteur - Centre de Recherche Nucleaire Draria (CRND), BP 43 Sebala DRARIA - Algiers (Algeria); Hamidouche, Tewfik [Laboratoire des Analyses de Surete, Centre de Recherche Nucleaire d' Alger (CRNA), 02 Boulevard Frantz Fanon, B.P. 399, 16000 Algiers (Algeria)]. E-mail: thamidouche@comena-dz.org; Si-Ahmed, El Khider [Laboratoire des Ecoulements Polyhpasiques, Universite des Sciences et de la Technologie d' Alger, Algiers (Algeria)

    2006-03-15

    During a loss of coolant accident leading to total emptying of the reactor pool, the decay heat could be removed through air natural convection. However, under partial pool emptying the core is partially submerged and the coolant circulation inside the fuel element could no more be possible. Under such conditions, a core overheat takes place, and the thermal energy is essentially diffused from the core to its periphery by combined thermal radiation and conduction. In order to predict fuel element temperature evolution under such conditions a mathematical model is performed. The model is based on a 3D geometry and takes into account a variety of core configurations including fuel elements (standard and control), reflector elements and grid plates. The homogeneous flow model is used and the fluid conservation equations are solved using a semi-implicit finite difference method. Preliminary tests of the developed model were made by considering a series of hypothetical accidents. In the current framework a loss of decay heat removal accidents in the IAEA benchmark open pool MTR-type research reactor is considered. It is shown that in the case of a low core immersion height no water boiling is observed and the fuel surface temperature rise remains below the melting point of the aluminium cladding.

  16. Incorporation of severe accidents in the licensing of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Alvarenga, Marco Antonio Bayout; Rabello, Sidney Luiz, E-mail: bayout@cnen.gov.b, E-mail: sidney@cnen.gov.b [Comissao Nacional de Energia Nuclear (CNEN) Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Severe accidents are the result of multiple faults that occur in nuclear power plants as a consequence from the combination of latent failures and active faults, such as equipment, procedures and operator failures, which leads to partial or total melting of the reactor core. Regardless of active and latent failures related to the plant management and maintenance, aspects of the latent failures related to the plant design still remain. The lessons learned from the TMI accident in the U.S.A., Chernobyl in the former Soviet Union and, more recently, in Fukushima, Japan, suggest that severe accidents must necessarily be part of design-basis of nuclear power plants. This paper reviews the normative basis of the licensing of nuclear power plants concerning to severe accidents in countries having nuclear power plants under construction or in operation. It was addressed not only the new designs of nuclear power plants in the world, but also the design changes in plants that are in operation for decades. Included in this list are the Brazilian nuclear power plants, Angra-1, Angra-2, and Angra-3. This paper also reviews the current status of licensing in Brazil and Brazilian standards related to severe accidents. It also discusses the impact of severe accidents in the emergency plans of nuclear power plants. (author)

  17. Development of a three-dimensional model and calculation code for the packed bed simulation for safety analyses of severe reactor accidents; Entwicklung eines dreidimensionalen Modells und Rechencodes zur Simulation von Schuettbetten fuer Sicherheitsanalysen von schweren Reaktorstoerfaellen

    Energy Technology Data Exchange (ETDEWEB)

    Berkhan, Ana; Starflinger, Joerg [Stuttgart Univ. (Germany). Inst. fuer Kernenergetik und Energiesysteme (IKE)

    2013-07-01

    The computer code MEWA is used for the description of severe accident sequences in light-water reactors. During the reactor accident with core disruption the solidified core fragments are displaced into the lower plenum of the reactor pressure vessel (RPV) or in case of RPV failure into the water filled reactor sump. For the progress or cessation of the severe accident the cooling of the packed bed is of main importance. With the 3D version of the code it is possible to study spatially complex packed beds with respect to their coolability. Further extension of the MEWA code will include the optimization for the improvement of the calculation efficiency and reduction of computation time. The validation will be performed by re-calculation of experiments (for instance DEBRIS experiments at the IKE) and the comparison with results of the 2D version.

  18. Neutronics aspects associated to the prevention and mitigation of severe accidents in sodium cooled reactor cores; Aspects de neutronique associes a la prevention et a la reduction des accidents graves dans les coeurs de reacteurs a caloporteur sodium

    Energy Technology Data Exchange (ETDEWEB)

    Poumerouly, S.

    2010-12-15

    release stops i.e. when the core is back to criticality. This enabled to find which magnitude the secondary power excursion could have depending on the upper configuration lay out. The study showed that no configuration is quite favourable and that in order to reduce the energy release, dispositions should be taken during the primary phase. SIMMER is also used to perform transient calculations on the core SFRv2b for the whole scenario of the ULOF and TIB accidents. For the ULOF calculation, the standard procedure is to calculate the primary phase with SAS4A and then to continue with SIMMER. However, since this procedure has some deficiencies, SIMMER was used for the primary phase also.The comparison between the two methods illustrates the difficulties of both approaches. SIMMER gives quite good results, but improvements are however necessary, e.g. on the axial expansion of fuel. Although approximate, results show that the event is too quick to activate any passive mitigating system. Work should be conducted on core designs (for instance by improving feedback effects) so as to give more time for passive mitigating systems to operate. For the TIB calculation, large cores, like the SFRV2b one, require the use of SIMMER neutronics. This in conjunction with thermal hydraulic requires some specific procedures which were investigated. SIMMER calculations with coarse meshes show their limits when compared to the SCARABEE experiments. There are significant discrepancies that could be reduced using fine meshes and a more accurate modelling of the pin and the subassembly. Improvements in the code are necessary to represent correctly the TIB on a reactor case. However, even with the current approximate method, some conclusions and recommendations could be drawn on the means of detecting the accident by delayed neutron detectors or by thermal couples before its propagation to the whole core. (author)

  19. Zirconium carbide coating for corium experiments related to water-cooled and sodium-cooled reactors

    Science.gov (United States)

    Plevacova, K.; Journeau, C.; Piluso, P.; Zhdanov, V.; Baklanov, V.; Poirier, J.

    2011-07-01

    Since the TMI and Chernobyl accidents the risk of nuclear severe accident is intensively studied for existing and future reactors. In case of a core melt-down accident in a nuclear reactor, a complex melt, called corium, forms. To be able to perform experiments with prototypic corium materials at high temperature, a coating which resists to different corium melts related to Generation I and II Water Reactors and Generation IV sodium fast reactor was researched in our experimental platforms both in IAE NNC in Kazakhstan and in CEA in France. Zirconium carbide was selected as protective coating for graphite crucibles used in our induction furnaces: VCG-135 and VITI. The method of coating application, called reactive wetting, was developed. Zirconium carbide revealed to resist well to the (U x, Zr y)O 2-z water reactor corium. It has also the advantage not to bring new elements to this chemical system. The coating was then tested with sodium fast reactor corium melts containing steel or absorbers. Undesirable interactions were observed between the coating and these materials, leading to the carburization of the corium ingots. Concerning the resistance of the coating to oxide melts without ZrO 2, the zirconium carbide coating keeps its role of protective barrier with UO 2-Al 2O 3 below 2000 °C but does not resist to a UO 2-Eu 2O 3 mixture.

  20. What are the consequences of the reactor accident in Fukushima for the evaluation of nuclear risk?; Welche Folgen hat der Kernkraftwerksunfall in Fukushima fuer die Bewertung von Kernenergierisiken?

    Energy Technology Data Exchange (ETDEWEB)

    Renn, Ortwin [Univ. Stuttgart (Germany). Inst. Sozialwissenshaften V; Gallego Carrera, Diana [Univ. Stuttgart (Germany). ZIRIUS Zentrum fuer Interdiszipliaere Risiko- und Innovationsforschung

    2015-06-01

    There are historical breaks in the relation of risk analysis, risk perception and regulation policy. The year 2011 with the reactor accident in the NPP Fukushima was such a break, especially in Germany. The nuclear phase-out was reduced to ten years the energy policy turnaround received a broad societal agreement. Nuclear facilities loose public acceptance, the risk perception has changed. The Japanese evaluation results on faulty and nontransparent behavior and the lack of governance of responsible persons and authorities including a poor accident management have further decreased the public confidence. A new concept of safety culture for all nuclear facilities including the radioactive waste management is required, the communication processes between plant operator, authorities, science and the public have to be intensified.

  1. Statistical analysis of the blowdown phase of a loss-of-coolant accident in a pressurized water reactor as calculated by RELAP4/MOD6

    Energy Technology Data Exchange (ETDEWEB)

    Berman, M.; Byers, R.K.; Steck, G.P.

    1979-01-01

    A statistical study is presented of the blowdown phase of a design basis accident (double-ended cold leg guillotine break) in the Zion pressurized water reactor. The response surface method was employed to generate a polynomial approximation of the peak clad temperatures calculated by RELAP4/MOD6. The nodalization was a modification of the RELAP model of Zion developed in the BE/EM study. Twenty one variables were initially selected for the study. These variables, their ranges and distributions resulted from the best engineering judgement of NRC, Sandia, INFL, and other interested and knowledgeable investigators.

  2. Updated action plan for the implementation of measures as a consequence of the Fukushima reactor accident; Fortgeschriebener Aktionsplan zur Umsetzung von Massnahmen nach dem Reaktorunfall in Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-03-15

    The updated German action plan for the implementation of measures as a consequence of the Fukushima reactor accident covers the following issues: decision on the future utilization of nuclear energy in Germany; national frame for security checks, inspections and measures for nuclear power plants; international frame for inspections; action plan and WENRA reference level; action plan for the implementation of measures form robustness enhancement in German nuclear power plants (SNC topics 1-3), action plan for implementation of further measures (CNS topics 4-6).

  3. Physicochemical processes taking place in the reactor core under severe accident conditions. Procesos fisicoquimicos que tienen lugar en el Nucleo de un reactor en conditiones de accidente severo

    Energy Technology Data Exchange (ETDEWEB)

    Esteban Hernandez, J.A.; Diaz Arocas, P.P.; Carrion Martin, J.G. (1-652-450 (Spain))

    1990-01-01

    Information is provided on UO[sup 2]-ZRY, ZRY steam and UO[sup 2] steam interactions. Performance of grid spacers. Integrated codes for analysis of accidents. Damage evolution of the Central module of the experiment LP-FP-2-Fission products generation. Physicochemical state of the fission products within oxide-type fuels. Solid radionuclide migration Behaviour of volatile fission products inside the fuel rods. Fission products release out of the fuel rods. Fission products behaviour under red and simulated accidents.

  4. Radiation and other risk issues in Norwegian newspapers ten years after Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Aa.; Reitan, J.B.; Toennesen, A.; Waldahl, R.

    1997-09-01

    Content analysis of risk articles has been performed in 1996 for five Norwegian newspapers four weeks before and four weeks after the 10th anniversary of the Chernobyl accident in 1986. The main focus has been on radiation and/or nuclear risks. The report is part of an international project on risk perception and communication. 94 refs.

  5. Iodine-129 and Caesium-137 in Chernobyl contaminated soil and their chemical fractionation

    DEFF Research Database (Denmark)

    Hou, Xiaolin; Fogh, C.L.; Kucera, J.

    2003-01-01

    Soil samples from areas in Belarus, Russia and Sweden contaminated by the Chernobyl accident were analysed for I-129 by radiochemical neutron activation analysis, as well as for Cs-137 by gamma-spectrometry. The atomic ratio of I-129/(CS)-C-137 in the upper layer of the examined soil cores ranged...

  6. Measurement of airborne 131I, 134Cs, and 137Cs nuclides due to the Fukushima reactors accident in air particulate in Milan (Italy)

    CERN Document Server

    Clemenza, Massimiliano; Previtali, Ezio; Sala, Elena

    2011-01-01

    After the earthquake and the tsunami occurred in Japan on 11th March 2011, four of the Fukushima reactors had released in air a large amount of radioactive isotopes that had been diffused all over the world. The presence of airborne 131I, 134Cs, and 137Cs in air particulate due to this accident has been detected and measured in the Low Radioactivity Laboratory operating in the Department of Environmental Sciences of the University of Milano-Bicocca. The sensitivity of the detecting apparatus is of 0.2 \\mu Bq/m3 of air. Concentration and time distribution of these radionuclides were determined and some correlations with the original reactor releases were found. Radioactive contaminations ranging from a few to 400 \\mu Bq/m3 for the 131I and of a few tens of \\mu Bq/m3 for the 137Cs and 134Cs have been detected

  7. Chernobyl: what sanitary consequences?; Tchernobyl: quelles consequences sanitaires?

    Energy Technology Data Exchange (ETDEWEB)

    Aurengo, A. [Assistance Publique, Hopitaux de Parix (AP-HP), 75 - Paris (France)

    2001-11-01

    Because of its public health, ecological and industrial consequences, the Chernobyl accident has become a myth which serves as the focus of many fears, justified or not. no one can question the seriousness of the event, but after fifteen years there is still no agreement about the effect it has had or will have on public health. For example, the total number of deaths attributed to Chernobyl varies from less than a hundred to several millions and congenital malformations from negligible to cataclysmic. Effects on public health may be calculated from data on contamination, from the dose received and from the risk, all three of which are likely to be very roughly known; or they may be evaluated on the spot, either by epidemiological studies or by examining medical registers. This report makes an inventory of the different risks and takes stock on them. (N.C.)

  8. A review of possible origins of the uranium 'plume' in the aquifer under the EPIC site in the Chernobyl Exclusion Zone

    Energy Technology Data Exchange (ETDEWEB)

    Simonucci, C.; Van Meir, N.; Courbet, C. [Institute for Radioprotection and Nuclear Safety, PRP-DGE/SRTG/LETIS, POB 17, F-92262, Fontenay-aux-Roses Cedex (France); Roux, C. [Institute for Radioprotection and Nuclear Safety, PRP-DGE/SRTG/LETIS, POB 17, F-92262, Fontenay-aux-Roses Cedex (France); Aix-Marseille University, CNRS, IRD, CEREGE UM34, 13545 Aix en Provence (France); Le Gal La Salle, C.; Verdoux, P.; Lancelot, J.C. [Nimes University, Laboratoire de Geochimie Isotopique (GIS), 150 rue George Besse, 30035 Nimes (France); Ruas, A. [CEA, Nuclear Energy Division, RadioChemistry and Processes Department, F-30207, Bagnols-sur-Ceze (France); Bassot, S. [Institute for Radioprotection and Nuclear Safety, PRP-DGE/SRTG/LAME, POB 17, F-92262, Fontenay-aux-Roses Cedex (France); Bugai, D. [Institute of Geological Sciences, 55-b, Gonchara Str., Kiev 01054 (Ukraine); Levchuk, S.; Kashparov, V. [Ukrainian Institute of Agricultural Radiology, UIAR NUBiP of Ukraine, Mashinobudivnykiv str. 7, Chabany, Kyiv-Svjatoshin (Ukraine)

    2013-07-01

    The uniqueness of the Chernobyl accident lies in the fact that so much radioactive material was discharged to the atmosphere as solid fuel particles from the reactor core. Between the 26 April and the 6 May 1986 more than 6 tons of small particles of highly radioactive uranium oxide fuel were discharged to the atmosphere and were responsible for more than 75 % of the radioactive contamination on the ground in the exclusion zone. In 1987, about 800 trenches had been dug in the exclusion zone to prevent re-suspension and to protect workers from contamination. In 1999, the IRSN, in collaboration with IGS and UIAR, equipped trench 22 (CPS) in order to monitor radionuclide migration in the environment (water, soil, plants). At the EPIC site high uranium concentrations were observed in the groundwater downstream from trench 22. We discuss the possible origins of this uranium 'plume'. (authors)

  9. Chernobyl, 25 years later, demographical situation and health problems in the contaminated territories; Tchernobyl, 25 ans apres, Situation demographique et problemes de sante dans les territoires contamines

    Energy Technology Data Exchange (ETDEWEB)

    Bandajevski, Yury I.; Bandajevskaya, G.S. [Centre d' analyse et de coordination ' Ecologie et Sante' (Belarus); Dubovaya, Natalia; Kadun, O.N. [Centre d' analyse et de coordination ' Ecologie et Sante' (Ukraine)

    2011-04-15

    On April 26, 1986, the reactor no.4 of the Chernobyl power plant (Ukraine) exploded. The real human impact of this catastrophe is still unknown. Today, 1.4 million people, included 260.000 children, are living in contaminated areas. What is the population situation of these areas and what are the actual health problems encountered? Written by scientists who have worked for 25 years in contaminated areas, this book follows two goals: - providing the reader with verified and reliable information about the accident impacts on public health and demography; - proposing a remedial action plan aiming at improving the health of the populations living in the contaminated areas (named 'model of life system in a radioactivity contaminated territory'). (J.S.)

  10. Gene signature of the post-Chernobyl papillary thyroid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Handkiewicz-Junak, Daria; Rusinek, Dagmara; Oczko-Wojciechowska, Malgorzata; Kowalska, Malgorzata; Jarzab, Barbara [Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Department of Nuclear Medicine and Endocrine Oncology, Gliwice (Poland); Swierniak, Michal [Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Department of Nuclear Medicine and Endocrine Oncology, Gliwice (Poland); Medical University of Warsaw, Genomic Medicine, Department of General, Transplant and Liver Surgery, Warsaw (Poland); Dom, Genevieve; Maenhaut, Carine; Detours, Vincent [Universite libre de Bruxelles (ULB), Institute of Interdisciplinary Research, Bruxelles (Belgium); Unger, Kristian [Imperial College London Hammersmith Hospital, Human Cancer Studies Group, Division of Surgery and Cancer, London (United Kingdom); Helmholtz-Zentrum, Research Unit Radiation Cytogenetics, Munich (Germany); Bogdanova, Tetiana [Institute of Endocrinology and Metabolism, Kiev (Ukraine); Thomas, Geraldine [Imperial College London Hammersmith Hospital, Human Cancer Studies Group, Division of Surgery and Cancer, London (United Kingdom); Likhtarov, Ilya [Academy of Technological Sciences of Ukraine, Radiation Protection Institute, Kiev (Ukraine); Jaksik, Roman [Silesian University of Technology, Systems Engineering Group, Faculty of Automatic Control, Electronics and Informatics, Gliwice (Poland); Chmielik, Ewa [Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Department of Tumour Pathology, Gliwice (Poland); Jarzab, Michal [Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, IIIrd Department of Radiation Therapy, Gliwice (Poland); Swierniak, Andrzej [Silesian University of Technology, Department of Automatic Control, Gliwice (Poland)

    2016-07-15

    Following the nuclear accidents in Chernobyl and later in Fukushima, the nuclear community has been faced with important issues concerning how to search for and diagnose biological consequences of low-dose internal radiation contamination. Although after the Chernobyl accident an increase in childhood papillary thyroid cancer (PTC) was observed, it is still not clear whether the molecular biology of PTCs associated with low-dose radiation exposure differs from that of sporadic PTC. We investigated tissue samples from 65 children/young adults with PTC using DNA microarray (Affymetrix, Human Genome U133 2.0 Plus) with the aim of identifying molecular differences between radiation-induced (exposed to Chernobyl radiation, ECR) and sporadic PTC. All participants were resident in the same region so that confounding factors related to genetics or environment were minimized. There were small but significant differences in the gene expression profiles between ECR and non-ECR PTC (global test, p < 0.01), with 300 differently expressed probe sets (p < 0.001) corresponding to 239 genes. Multifactorial analysis of variance showed that besides radiation exposure history, the BRAF mutation exhibited independent effects on the PTC expression profile; the histological subset and patient age at diagnosis had negligible effects. Ten genes (PPME1, HDAC11, SOCS7, CIC, THRA, ERBB2, PPP1R9A, HDGF, RAD51AP1, and CDK1) from the 19 investigated with quantitative RT-PCR were confirmed as being associated with radiation exposure in an independent, validation set of samples. Significant, but subtle, differences in gene expression in the post-Chernobyl PTC are associated with previous low-dose radiation exposure. (orig.)

  11. Risks of potential accidents of nuclear power plants in Europe

    NARCIS (Netherlands)

    Slaper H; Eggink GJ; Blaauboer RO

    1993-01-01

    Over 200 nuclear power plants for commercial electricity production are presently operational in Europe. The 1986 accident with the nuclear power plant in Chernobyl has shown that severe accidents with a nuclear power plant can lead to a large scale contamination of Europe. This report is focussed

  12. Risks of potential accidents of nuclear power plants in Europe

    NARCIS (Netherlands)

    Slaper H; Eggink GJ; Blaauboer RO

    1993-01-01

    Over 200 nuclear power plants for commercial electricity production are presently operational in Europe. The 1986 accident with the nuclear power plant in Chernobyl has shown that severe accidents with a nuclear power plant can lead to a large scale contamination of Europe. This report is focussed o

  13. Possible pressurized thermal shock events during large primary to secondary leakage. The Hungarian AGNES project and PRISE accident scenarios in VVER-440/V213 type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Perneczky, L. [KFKI Atomic Energy Research Inst., Budabest (Hungary)

    1997-12-31

    Nuclear power plants of WWER-440/213-type have several special features. Consequently, the transient behaviour of such a reactor system should be different from the behaviour of the PWRs of western design. The opening of the steam generator (SG) collector cover, as a specific primary to secondary circuit leakage (PRISE) occurring in WWER-type reactors happened first time in Rovno NPP Unit I on January 22, 1982. Similar accident was studied in the framework of IAEA project RER/9/004 in 1987-88 using the RELAP4/mod6 code. The Hungarian AGNES (Advanced General and New Evaluation of Safety) project was performed in the period 1991-94 with the aim to reassess the safety of the Paks NPP using state-of-the-art techniques. The project comprised three type of analyses for the primary to secondary circuit leakages: Design Basis Accident (DBA) analyses, Pressurized Thermal Shock (PTS) study and deterministic analyses for Probabilistic Safety Analysis (PSA). Major part of the thermohydraulic analyses has been performed by the RELAP5/mod2.5/V251 code version with two input models. 32 refs.

  14. Accidents in nuclear facilities: classification, incidence and impact; Accidentes en instalaciones nucleares: clasificacion, incidencia e impacto

    Energy Technology Data Exchange (ETDEWEB)

    Galicia A, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Paredes G, L. C., E-mail: blink19871@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    A general analysis of the 146 accidents reported officially in nuclear facilities from 1945 to 2012 is presented, among them some took place in: power or research nuclear reactors, critical and subcritical nuclear assemblies, handling of nuclear materials inside laboratories belonging to institutes or universities, in radiochemistry industrial plants and nuclear fuel factories. In form graph the incidence of these accidents is illustrated classified for; category, decades, geographical localization, country classification before the OECD, failure type, and the immediate or later victims. On the other hand, the main learned lessons of the nuclear accidents of Three Mile Island, Chernobyl and Fukushima are stood out, among those that highlight; the human factors, the necessity of designs more innovative and major technology for the operation, control and surveillance of the nuclear facilities, to increase the criterions of nuclear, radiological and physics safety applied to these facilities, the necessity to carry out probabilistic analysis of safety more detailed for cases of not very probable accidents and their impact, to revalue the selection criterions of the sites for nuclear locations, the methodology of post-accident sites recovery and major instrumentation for parameters evaluation and the radiological monitoring among others. (Author)

  15. Individual dose due to radioactivity accidental release from fusion reactor.

    Science.gov (United States)

    Nie, Baojie; Ni, Muyi; Wei, Shiping

    2017-04-05

    As an important index shaping the design of fusion safety system, evaluation of public radiation consequences have risen as a hot topic on the way to develop fusion energy. In this work, the comprehensive public early dose was evaluated due to unit gram tritium (HT/HTO), activated dust, activated corrosion products (ACPs) and activated gases accidental release from ITER like fusion reactor. Meanwhile, considering that we cannot completely eliminate the occurrence likelihood of multi-failure of vacuum vessel and tokamak building, we conservatively evaluated the public radiation consequences and environment restoration after the worst hypothetical accident preliminarily. The comparison results show early dose of different unit radioactivity release under different conditions. After further performing the radiation consequences, we find it possible that the hypothetical accident for ITER like fusion reactor would result in a level 6 accident according to INES, not appear level 7 like Chernobyl or Fukushima accidents. And from the point of environment restoration, we need at least 69 years for case 1 (1kg HTO and 1000kg dust release) and 34-52years for case 2 (1kg HTO and 10kg-100kg dust release) to wait the contaminated zone drop below the general public safety limit (1mSv per year) before it is suitable for human habitation.

  16. International law problems for realisation of the IAEA conventions on notification and assistance in the case of a nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, M.M.

    1993-12-31

    The Chernobyl accident underscored the need for an early warning system and international assistance plan in case of a nuclear accident. Shortly after Chernobyl, two conventions were adopted under the auspices of the IAEA. The convention on Early Notification of a Nuclear Accident, in force since 1986, establishes an early warning system for all nuclear accidents whose effects might cross national boundaries. Under the convention on Assistance in the Case of a Nuclear accident or radiological Emergency,in force since 1987, countries must facilitate prompt assistance in case of a nuclear accident or radiological emergency, to minimize it`s consequences. Issues with the conventions are described.

  17. Chernobyl fallout measurements in some Mediterranean biotas.

    Science.gov (United States)

    Barci, G; Dalmasso, J; Ardisson, G

    1988-03-01

    The radioactivity of various terrestrial vegetation leaves characteristic of Mediterranean countries has been measured after the Chernobyl accident. In addition, we paid particular attention to lichens and seaweed which are considered as bioindicators of radioactive contamination. Most measurements were performed non-destructively using both coaxial and planar HPGe detectors. For odd mass radionuclides having low energy lines, such as 125Sb or 141Ce the sensitivity of the planar HPGe detector is better than the coaxial detector. The concentration of long-lived fission nuclides remaining three months after the accident were found to be enhanced in needle form leaves and in lichens. The seaweed Sphaerococcus exhibits a strong specific activity for iodine and ruthenium elements and poor concentration for caesium nuclides. The activity ratios of different isotopes of the same element measured in vegetation samples agree well with values found in airborne aerosols by other authors. The activation nuclide 110mAg is found in all samples with the same ratio 110mAg/137Cs = (1.0 +/- 0.2).10(-2) as in the soil deposition.

  18. SARNET european excellence network on nuclear reactor major accidents. Display and realizations after a year of operating; Sarnet reseau d'excellence europeen sur les accidents graves de reacteur nucleaire. Son deploiement et ses realisations apres une annee de fonctionnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-03-15

    The Sarnet (Severe Accident Research NETwork of excellence) is devoted to the research on major accidents of water cooled reactors. The developed knowledge will be integrated in a simulation tool ASTEC co-developed with the IRSN and the GRS. This evaluation report presents the context, the objectives and the program of the Sarnet network. It discusses the network operating and the ASTEC simulation code. Some examples of experimental programs are provided. (A.L.B.)

  19. Jules Horowitz reactor - Complementary safety assessment in the light of the Fukushima accident; Reacteur Jules Horowitz - Evaluation complementaire de la surete au regard de l'accident survenu a la centrale nucleaire de Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-13

    This CSA (Complementary Safety Assessment) analyses the robustness of the Jules Horowitz reactor (RJH) to extreme situations such as those that led to the Fukushima accident and proposes a series of improvements. RJH is being built on the Cadarache CEA's site. Robustness is the ability for the facility to withstand events beyond the level for which the facility was designed. Robustness is linked to safety margins but also to the situations leading to a sudden deterioration of the accident sequence (cliff edge effect). Safety is not only a matter of design or of engineered systems, it is also a matter of organization. So issues like RJH's crisis organization, the organization of radiation protection, and work organization via subcontracting are also taken into consideration. This report is divided into 9 main chapters: 1) main features of the RJH facility, 2) identification of cliff edge risks and of equipment essential for safety, 3) earthquake risk, 4) flood risk, 5) risks due to other extreme natural disasters, 6) the loss of electrical power supplies and of cooling systems, 7) management of severe accidents, 8) subcontracting policy, 9) synthesis and list of improvements. This study shows a globally good robustness of the RJH for the considered risks. Nevertheless it can considered relevant to increase the robustness of the plant on a few points: -) to increase the seismic safety margins of some pieces of equipment, -) to increase the robustness of the internal electrical power supplies, -) to increase the fuel cooling capacity, and -) to improve the management of the post-accidental period. (A.C.)

  20. Analysis on the `Thermite` reaction consequences in accidents involving research reactors using plate-type fuel; Analisis sobre las concequencias de la reaccion `Termita` en caso de accidentes en reactores de investigacion que utilizan combustible tipo placa

    Energy Technology Data Exchange (ETDEWEB)

    Boero, Norma L.; Bruno, Hernan R.; Camacho, Esteban F.; Cincotta, Daniel O.; Yorio, Daniel [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Constituyentes

    1999-11-01

    The mixture of Al-U{sub 3} O{sub 8} is not in a state of chemical equilibrium, and at temperatures of between 850 deg C and 1000 deg C, it reacts exo thermally. This is known, in corresponding bibliography as a `Thermite reaction. This mixture is used in the manufacturing of the plate-type fuel used in research reactors. It has been pointed out that the release of energy caused by this type of reactions might represent a risk in case of accidents in this type of reactor. Conclusions, in general, tend to indicate that no such risk exists, although no concrete assurance is given that this is the case, and this fact, therefore, leaves room for doubt. The objective of this paper is to provide an in-depth study of what happens to a fuel plate when it is subjected to thermite reaction. We will, furthermore, analyze the consequences of the release of energy generated by this type of reaction within the core of the reactor, clearly defining the problem for this type of fuel and this kind of reactor. (author) 3 refs., 9 figs., 1 tab.

  1. Particular Qualities of Soviet Information Policy according Chornobyl Accident: Source Study Aspects of the Problem

    Directory of Open Access Journals (Sweden)

    O. Makhno

    2016-07-01

    Full Text Available The article identifies the main groups of historical sources for a comprehensive study of Soviet information policy with respect to the Chernobyl accident. Determine their informational potential, deals with the methods of source analysis.

  2. The potential use of Chernobyl fallout data to test and evaluate the predictions of environmental radiological assessment models

    Energy Technology Data Exchange (ETDEWEB)

    Richmond, C.R.; Hoffman, F.O.; Blaylock, B.G.; Eckerman, K.F.; Lesslie, P.A.; Miller, C.W.; Ng, Y.C.; Till, J.E.

    1988-06-01

    The objectives of the Model Validation Committee were to collaborate with US and foreign scientists to collect, manage, and evaluate data for identifying critical research issues and data needs to support an integrated assessment of the Chernobyl nuclear accident; test environmental transport, human dosimetric, and health effects models against measured data to determine their efficacy in guiding decisions on protective actions and in estimating exposures to populations and individuals following a nuclear accident; and apply Chernobyl data to quantifications of key processes governing the environmental transport, fate and effects of radionuclides and other trace substances. 55 refs.

  3. Chernobyl. Tsjernobyl; Sluttrapport fra NINA's radiooekologiprogram 1986-1990

    Energy Technology Data Exchange (ETDEWEB)

    Gaare, E.; Jonsson, B.; Skogland, T. (eds.)

    1991-04-01

    Due to southeasterly wind and rainfall during the critical days after the Chernobyl accident, Norway got a substantial part of the cesium isotopes released. The radioactive fallout followed closely the rainfall and was mainly concentrated to some thin populated areas in the central parts of the country. This report summerize the results from a post-Chernobyl research program on aquatic and terrestrial ecosystems in contaminated areas. Pathways, processes and factors determining the Cs-137 concentration in soil, plant, water, fish and wild animal were investigated. 84 refs., 40 figs., 20 tabs.

  4. Nuclear power debate and public opinion in Belarus: From Chernobyl to Ostrovets.

    Science.gov (United States)

    Novikau, Aliaksandr

    2016-05-05

    The Belarusian government's decision of the last decade to build a nuclear power plant near the city of Ostrovets, in northern Belarus, has proven to be controversial, resulting in a great deal of debate about nuclear energy in the country. The debate was inevitably shaped by the traumatic event that affected Belarus - the Chernobyl nuclear accident of 1986. The Belarusian authorities have consistently promoted a positive view of nuclear energy to the population in order to overcome the so-called 'Chernobyl syndrome' and deliberately shaped nuclear risk communication. As a result, the issue of trust remains crucial in all nuclear debates in Belarus.

  5. ENVIRONMENTAL RADIATION MONITORING IN THE CHERNOBYL EXCLUSION ZONE - HISTORY AND RESULTS 25 YEARS AFTER

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.

    2011-10-01

    This article describes results of the radiation environmental monitoring performed in the Chernobyl Exclusion Zone (ChEZ) during the period following the 1986 Chernobyl Nuclear Power Plant accident. This article presents a brief overview of five comprehensive reports generated under Contract No. DE-AC09-96SR18500 (Washington Savannah River Company LLC, Subcontract No. AC55559N, SOW No. ON8778) and summarizes characteristics of the ChEZ and its post-accident status and the history of development of the radiation monitoring research in the ChEZ is described. This article addresses characteristics of the radiation monitoring in the ChEZ, its major goals and objectives, and changes of these goals and objectives in the course of time, depending on the tasks associated with the phase of mitigation of the ChNPP accident consequences. The results of the radiation monitoring in the ChEZ during the last 25 years are also provided.

  6. Code assessment and modelling for Design Basis Accident analysis of the European Sodium Fast Reactor design. Part II: Optimised core and representative transients analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lazaro, A., E-mail: aulach@iqn.upv.es [JRC-IET European Commission, Westerduinweg 3, PO BOX 2, 1755 ZG Petten (Netherlands); Schikorr, M. [KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Mikityuk, K. [PSI, Paul Scherrer Institut, 5232 Villigen (Switzerland); Ammirabile, L. [JRC-IET European Commission, Westerduinweg 3, PO BOX 2, 1755 ZG Petten (Netherlands); Bandini, G. [ENEA, Via Martiri di Monte Sole 4, 40129 Bologna (Italy); Darmet, G.; Schmitt, D. [EDF, 1 Avenue du Général de Gaulle, 92141 Clamart (France); Dufour, Ph.; Tosello, A. [CEA, St. Paul lez Durance, 13108 Cadarache (France); Gallego, E.; Jimenez, G. [UPM, José Gutiérrez Abascal, 2, 28006 Madrid (Spain); Bubelis, E.; Ponomarev, A.; Kruessmann, R.; Struwe, D. [KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Stempniewicz, M. [NRG, Utrechtseweg 310, P.O. Box-9034, 6800 ES Arnhem (Netherlands)

    2014-10-01

    Highlights: • Benchmarked models have been applied for the analysis of DBA transients of the ESFR design. • Two system codes are able to simulate the behavior of the system beyond sodium boiling. • The optimization of the core design and its influence in the transients’ evolution is described. • The analysis has identified peak values and grace times for the protection system design. - Abstract: The new reactor concepts proposed in the Generation IV International Forum require the development and validation of computational tools able to assess their safety performance. In the first part of this paper the models of the ESFR design developed by several organisations in the framework of the CP-ESFR project were presented and their reliability validated via a benchmarking exercise. This second part of the paper includes the application of those tools for the analysis of design basis accident (DBC) scenarios of the reference design. Further, this paper also introduces the main features of the core optimisation process carried out within the project with the objective to enhance the core safety performance through the reduction of the positive coolant density reactivity effect. The influence of this optimised core design on the reactor safety performance during the previously analysed transients is also discussed. The conclusion provides an overview of the work performed by the partners involved in the project towards the development and enhancement of computational tools specifically tailored to the evaluation of the safety performance of the Generation IV innovative nuclear reactor designs.

  7. Airborne Gamma-ray Measurements in the Chernobyl Plume

    DEFF Research Database (Denmark)

    Grasty, R. L.; Hovgaard, Jens; Multala, J.

    1997-01-01

    On 29 April 1986, the Geological Survey of Finland (GSF) survey aircraft with a gamma ray spectrometer flew through a radioactive plume from the Chernobyl nuclear accident. The aircraft became contaminated and the gamma spectrometer measured radioactivity in the plume as well as radioactivity...... on the aircraft. By using simple assumptions on the build-up of contamination it has been possible to separate the signals from contamination and from plume. The analysis further showed that even a detector/spectrometer with low energy resolution is able to identify a contamination with iodine....

  8. Fuel handling accident analysis for the University of Missouri Research Reactor's High Enriched Uranium to Low Enriched Uranium fuel conversion initiative

    Science.gov (United States)

    Rickman, Benjamin

    In accordance with the 1986 amendment concerning licenses for research and test reactors, the MU Research Reactor (MURR) is planning to convert from using High-Enriched Uranium (HEU) fuel to the use of Low-Enriched Uranium (LEU) fuel. Since the approval of a new LEU fuel that could meet the MURR's performance demands, the next phase of action for the fuel conversion process is to create a new Safety Analysis Report (SAR) with respect to the LEU fuel. A component of the SAR includes the Maximum Hypothetical Accident (MHA) and accidents that qualify under the class of Fuel Handling Accidents (FHA). In this work, the dose to occupational staff at the MURR is calculated for the FHAs. The radionuclide inventory for the proposed LEU fuel was calculated using the ORIGEN2 point-depletion code linked to the MURR neutron spectrum. The MURR spectrum was generated from a Monte Carlo Neutron transPort (MCNP) simulation. The coupling of these codes create MONTEBURNS, a time-dependent burnup code. The release fraction from each FHA within this analysis was established by the methodology of the 2006 HEU SAR, which was accepted by the NRC. The actual dose methodology was not recorded in the HEU SAR, so a conservative path was chosen. In compliance to NUREG 1537, when new methodology is used in a HEU to LEU analysis, it is necessary to re-evaluate the HEU accident. The Total Effective Dose Equivalent (TEDE) values were calculated in addition to the whole body dose and thyroid dose to operation personnel. The LEU FHA occupational TEDE dose was 349 mrem which is under the NRC regulatory occupational dose limit of 5 rem TEDE, and under the LEU MHA limit of 403 mrem. The re-evaluated HEU FHA occupational TEDE dose was 235 mrem, which is above the HEU MHA TEDE dose of 132 mrem. Since the new methodology produces a dose that is larger than the HEU MHA, we can safely assume that it is more conservative than the previous, unspecified dose.

  9. Small modular reactor (SMR) development plan in Korea

    Science.gov (United States)

    Shin, Yong-Hoon; Park, Sangrok; Kim, Byong Sup; Choi, Swongho; Hwang, Il Soon

    2015-04-01

    Since the first nuclear power was engaged in Korean electricity grid in 1978, intensive research and development has been focused on localization and standardization of large pressurized water reactors (PWRs) aiming at providing Korean peninsula and beyond with economical and safe power source. With increased priority placed on the safety since Chernobyl accident, Korean nuclear power R&D activity has been diversified into advanced PWR, small modular PWR and generation IV reactors. After the outbreak of Fukushima accident, inherently safe small modular reactor (SMR) receives growing interest in Korea and Europe. In this paper, we will describe recent status of evolving designs of SMR, their advantages and challenges. In particular, the conceptual design of lead-bismuth cooled SMR in Korea, URANUS with 40˜70 MWe is examined in detail. This paper will cover a framework of the program and a strategy for the successful deployment of small modular reactor how the goals would entail and the approach to collaboration with other entities.

  10. Fukushima, an accident which will leave a deep mark in the nuclear industry; Fukushima, un accident qui laissera une marque profonde sur le nucleaire civil

    Energy Technology Data Exchange (ETDEWEB)

    Vallee, Alain [International Nuclear Academy, 1, avenue de Verdun, BP 60190, 71105 Chalon-sur-Saone Cedex (France)

    2011-07-01

    Fukushima is the third major accident in the short history of civilian nuclear reactors. As the two previous ones, Three Mile Island and Chernobyl, it has delivered lessons which have to be learnt by governments, nuclear organizations and industry. Among them, the most important ones are the followings: - The past upgrades of the operating reactors against severe accidents has to be reassessed; - The requirements on the plant to sustain external hazards (earthquakes, flooding,...) has to be reviewed and improved in some cases; - Plants have to be tested against unrealistic situations to verify that no cliff edge effect can be expected; - The competence and the independence of the Safety Bodies have to be verified. The situation in the Fukushima reactors is not yet completely stabilized and it will take years before a return to normal life in the vicinity can take place; nevertheless, considering the size of the disaster, due to the exceptional magnitude of the earthquake and the height of the tsunami, the consequences of the nuclear part of the event are rather low: no casualty and limited risks of cancer for people in the future. (author)

  11. Safety analysis of a loss-of-coolant accident in a breeding blanket for experimental fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rocco, P.; Casini, G.; Djerassi, H.; Papa, L.; Pautasso, G.; Renda, V.; Rouyer, J.L.

    1985-07-01

    A LOCA in a blanket design proposed for NET (Next European Torus) is investigated. The structural analysis of a damaged breeder unit shows that this first containment barrier has a high probability of survival to this accident. The radioactive sources involved are evaluated and an assessment is made of all containment barriers and associated protection systems.

  12. Accident Process and Consequence Research for LOCA Combining with Blackout Accident of Ship Reactor%船用堆破口叠加全船断电事故进程及后果研究

    Institute of Scientific and Technical Information of China (English)

    张帆; 陈航; 张彦招; 晏峰

    2015-01-01

    Using MELCOR code ,the combination of LOCA and blackout accident of ship reactor was modeled and calculated , and the accident process and source term release were researched . The results show that the accident leads to lower head of pressure vessel and bilge creep‐rupture finally without emergency power .The release fraction of inert gases and iodine are above 80% ,the main form of iodine is CsI with great deposit and less airborne fraction .The accident process is decided by the equiva‐lent diameter of break size .The production of H2 is decided by core temperature and water remaining in the core ,but has nothing to do with equivalent diameter of break size .T he probability of H2 detonation is unlikely to occur .T he results can provide tech‐nical support for emergency maintenance and emergency decision‐making .%采用M ELCOR程序,对船用堆破口叠加全船断电事故进行建模计算,并对事故进程和源项释放进行了研究。计算结果表明:若应急电源无法投入,最终将导致压力容器下封头失效和舱底失效;所研究事故的惰性气体、碘释放量均在80%以上,且释放的I主要以CsI形式存在,滞留量大,气载量小。事故进展快慢取决于破口当量尺寸,但氢气的产量与堆芯温度、堆芯残余水量相关,与破口当量尺寸无直接关系,堆舱内发生氢爆可能性不大。本文计算结果可为应急抢修和应急决策提供技术支持。

  13. Differences and similarities between behavior of Fukushima-derived and Chernobyl-derived radiocesium in the environment

    Science.gov (United States)

    Konoplev, Alexei; Nanba, Kenji; Onda, Yuichi; Golosov, Valentin; Wakiyama, Yoshifumi; Takase, Tsugiko; Yoschenko, Vasyl; Zheleznyak, Mark

    2016-04-01

    The mobility and bioavailability of radiocesium (r-Cs) of accidental origin is governed by the ratio of its chemical forms in fallout and site-specific environmental characteristics determining the rates of leaching, fixation-remobilization, as well as sorption-desorption of the mobile fraction (its solid-liquid distribution). R-Cs in the environment is strongly bound to soil and sediment particles containing micaceous clay minerals (illite, vermiculite, etc.). This is associated with two basic processes - high selective reversible sorption and fixation. Climate and geographical conditions for Fukushima Prefecture of Japan and Chernobyl zone differ. For example, the catchments of the Chernobyl zone are flat and characterized by low slopes, while Fukushima's watersheds are hilly with steep slopes. Annual precipitation also differs substantially, with annual average for Fukushima about 3 times higher than at Chernobyl. The soils on the north-east coast of the Honshu island that were primarily affected by the radioactive contamination from the Fukushima Daiichi nuclear power plant (FDNPP) accident differ significantly from the Chernobyl zone soils. The proportion of clays such as illite, vermiculite etc. is 20-30% at Fukushima, which is higher than in the sandy loam soils of the Chernobyl zone. In addition to the landscape differences, the speciation of r-Cs in fallout was also different between Fukushima and Chernobyl. It is a challenge to compare r-Cs behavior in FDNPP and Chernobyl zones. Comparative analysis has been carried out for r-Cs wash-off parameters and the distribution coefficient Kd in rivers and surface runoff on Fukushima and Chernobyl contaminated areas for the first years after the accidents. The r-Cs distribution coefficient in Fukushima rivers was 1-2 orders of magnitude higher than correspondent values for rivers and surface runoff of the Chernobyl zone. This suggests higher ability of Fukushima soils and sediments to bind r-Cs. The normalized

  14. Analysis of Radionuclide Releases from the Fukushima Dai-ichi Nuclear Power Plant Accident Part II

    Science.gov (United States)

    Achim, Pascal; Monfort, Marguerite; Le Petit, Gilbert; Gross, Philippe; Douysset, Guilhem; Taffary, Thomas; Blanchard, Xavier; Moulin, Christophe

    2014-03-01

    The present part of the publication (Part II) deals with long range dispersion of radionuclides emitted into the atmosphere during the Fukushima Dai-ichi accident that occurred after the March 11, 2011 tsunami. The first part (Part I) is dedicated to the accident features relying on radionuclide detections performed by monitoring stations of the Comprehensive Nuclear Test Ban Treaty Organization network. In this study, the emissions of the three fission products Cs-137, I-131 and Xe-133 are investigated. Regarding Xe-133, the total release is estimated to be of the order of 6 × 1018 Bq emitted during the explosions of units 1, 2 and 3. The total source term estimated gives a fraction of core inventory of about 8 × 1018 Bq at the time of reactors shutdown. This result suggests that at least 80 % of the core inventory has been released into the atmosphere and indicates a broad meltdown of reactor cores. Total atmospheric releases of Cs-137 and I-131 aerosols are estimated to be 1016 and 1017 Bq, respectively. By neglecting gas/particulate conversion phenomena, the total release of I-131 (gas + aerosol) could be estimated to be 4 × 1017 Bq. Atmospheric transport simulations suggest that the main air emissions have occurred during the events of March 14, 2011 (UTC) and that no major release occurred after March 23. The radioactivity emitted into the atmosphere could represent 10 % of the Chernobyl accident releases for I-131 and Cs-137.

  15. FUKUSHIMA – 25 YEARS AFTER CHERNOBYL

    Directory of Open Access Journals (Sweden)

    Jan Grzesik

    2011-12-01

    Full Text Available The paper considers health risk of Japanese population and neighboring countries being the consequence of the major accident (level 7 on INES scale in Fukushima Dai-ichi I nuclear power station. On March 11 an earthquake of magnitude 9 on Richter scale, off the Pacific coast of the Japanese main land, caused a massive tsunami that crippled the cooling systems at the nuclear plant. That led to reactor meltdowns, hydrogen explosions, and major release of radioactive material into the air. To enable a better understanding of the different and severe consequences of the accident, the article describes the physical background of functioning of nuclear reactors, the hypothetical reasons of damages and interference of their operations, the mechanism of releasing radioactive pollutants into the atmosphere and the consequences for the population living in the area, on which radioactive fallout is observed The accident in Fukushima is remarkable because for the first time considerable amounts of plutonium isotope 239Pu were released into the environment. The author presents his negative opinion concerning the prospect that nuclear power stations will be 100% failure-free and will be totally safe for human population. The Fukushima nuclear disaster is the third major accident known in the history of nuclear power plants caused or enabled by man. Attention is also paid to phenomenon of lobbing pro existence and development of nuclear power. It is motivated by selfish corporation interest in which representatives of scientific community, industrial corporations and military bodies play a significant role.

  16. Using the Star CCM+ software system for modeling the thermal state and natural convection in the melt metal layer during severe accidents in VVER reactors

    Science.gov (United States)

    Kochetov, N. A.; Loktionov, V. D.; Sidorov, A. S.

    2015-09-01

    The possibility of using the Star CCM+ software system for analyzing the thermal state of the melt pool metal layer generated as a result of melt stratification during a severe accident in pressure-vessel nuclear reactors is considered. In order to verify and substantiate the possibility of using this software system for modeling the natural convection processes in the melt at high values of the Rayleigh number, test problems were solved. The obtained results were found to be in good agreement with the known solutions and with the experimental data. The behavior of the melt metal layer was subjected to a parametric analysis for different melt heating conditions, the results of which showed that certain parameters have a determining influence on the so-called focusing effect and on the specific features of current in this layer.

  17. Chernobyl Nuclear Catastrophe and the High Risk Potential for Mental Retardation.

    Science.gov (United States)

    Holowinsky, Ivan Z.

    1993-01-01

    This report considers potential effects of the 1986 nuclear explosion at the Chernobyl (Ukraine) nuclear reactor. Approximately 17 million people, of whom 2.5 million were below the age of 5, are thought to have suffered some radioactive contamination. Many of these children are at high risk for mental retardation and learning disorders.…

  18. Seismic Shaking Table Requirements and Consideration of Fluid-Structure Interaction Effect in Seismic Response Analysis Model for In-Reactor Fuel Assembly Under Severe Earthquake Accident

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kanghee; Yoon, Kyungho; Kang, Heungsoek; Lee, Youngho; Kim, Hyungkyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Dynamic response of fuel assembly can be significantly affected by added hydrodynamic mass and additional damping from the fluid and flow inside operating reactor core. Added mass or hydrodynamic virtual mass from surrounding fluid medium can be theoretically estimated by the potential flow theory. Solving Laplace equation in terms of velocity potential can leads to calculate mass components in the mass matrix of simplified fuel FE model. Additional damping from the fluid and the flow inside reactor core are originated from fluid drag and flow lift force, respectively. Lift force from axial flow can increase fuel assembly damping by twice compared to still fluid damping from the loop testing. In practice, fuel assembly damping should be measured by mockup loop testing and referred to published data in the literature. The justification is performed via time history analysis with simplified dynamic model using a group of fuel assembly in the core. Key check points in this analysis might be the integrity of intermediate spacer grids when impacting fuels into core shroud plate or into neighboring fuel assembly. Thus, dynamic displacement and impact force at grid elevations are the important structural parameters to be traced out during the analysis and the simulation testing. KAERI have a plan to develop dynamic analysis model and to setup test infrastructure for full scale and several fuel assembly rows seismic simulation testing. This paper briefly discuss on the reference earthquake accident scenario, shaking table requirements for full-scale seismic simulation testing, virtual testing issues before the hardware setup, and modelling issue related to fluid-structure interaction effect in accident core analysis.

  19. Natural and man-made radioactivity: Chernobyl soils.

    Science.gov (United States)

    Gillmore, Gavin; Flowers, Alan

    2014-05-01

    In 1986 a reactor at the Chernobyl Nuclear Plant suffered a large explosion. The result had wide-ranging impacts. 31 severely exposed emergency workers died from acute radiation syndrome and 19 more later died from different causes. The perhaps controversial prediction by some authors is that around 4,000 will eventually die as a result of the increased cancer risk. A 19-mile restriction zone exists around the former reactor, but during the past 25 years radiation levels have fallen and it is now possible to take part in conducted tours of the deserted city of Pripyat, and the Chernobyl reactor site. Soil levels, however, remain highly radioactive, particularly in the restricted area. Kingston University holds:- • Soil profile sets from 3 locations in Belarus, with repeats at same location 1996 and 2000. • Lake sediment core samples. • Soil profiles at forestry sites. • Surface samples in a region suspected to have actinide content at 200km from Chernobyl. In addition to the above the impact of naturally occurring radon on human health around Chernobyl should not be ignored. About 23 per cent of homes in Ukraine are estimated to have radon levels above 100 Bq m-3, whilst concentrations of 10,000 Bq m-3 or more are known to exist in public water supplies. Some researchers have also suggested that mean annual doses of irradiation of the population caused by radon and it's progeny in air in buildings exceeds the doses received now by inhabitants of settlements located in the territories polluted by Chernobyl-derived nuclides in the Mogilev and Gomel regions in Belarus. This project incorporates a temporal comparison of transport results in undisturbed soils variously over a number of years, demonstrating relative measurements using both the original and new samples. This project will also focus on lake sediments from Southern Belarus and is a 'work in progress'. However, what we can say at this stage is that it is notable that the long lived isotopes of Cs-137

  20. Source Term Analysis on Blackout Accident of Marine Reactor%船用堆全船断电事故源项分析

    Institute of Scientific and Technical Information of China (English)

    王伟; 陈力生; 张帆; 蔡琦

    2014-01-01

    Based on the integration program of MELCOR for severe accident analysis , the computational model of a typical marine reactor was established .The creep failure of pressurizer surge tube in the accident of blackout was verified ,and the behavior of the source term before and after the break of surge tube was analyzed .The results show that atmospheric environment and crew would suffer the radioactive harm .The smaller the surge tube break ,the slower the accident process .However ,the external radiation of the crew is slightly increased and the internal radiation is unchanged .The research results can provide a basis on further dose analysis of the source term and the emergency action inside and outside the ship .%本文以一体化严重事故分析程序M ELCOR为研究工具,建立了某型船用堆的计算模型。计算验证了全船断电事故稳压器波动管的蠕变失效,对波动管破损前后的源项行为进行了分析研究。结果表明:波动管失效直接导致对大气环境和船内人员的放射性危害。波动管破损尺寸的减小,导致失效后事故进程减慢,然而对船内人员的外照射危害略有提高,内照射危害相同。本文研究结果可为进一步的源项剂量分析及船内外应急提供依据。

  1. ROLE OF PASSIVE SAFETY FEATURES IN PREVENTION AND MITIGATION OF SEVERE PLANT CONDITIONS IN INDIAN ADVANCED HEAVY WATER REACTOR

    Directory of Open Access Journals (Sweden)

    VIKAS JAIN

    2013-10-01

    Full Text Available Pressing demands of economic competitiveness, the need for large-scale deployment, minimizing the need of human intervention, and experience from the past events and incidents at operating reactors have guided the evolution and innovations in reactor technologies. Indian innovative reactor ‘AHWR’ is a pressure-tube type natural circulation based boiling water reactor that is designed to meet such requirements, which essentially reflect the needs of next generation reactors. The reactor employs various passive features to prevent and mitigate accidental conditions, like a slightly negative void reactivity coefficient, passive poison injection to scram the reactor in event of failure of the wired shutdown systems, a large elevated pool of water as a heat sink inside the containment, passive decay heat removal based on natural circulation and passive valves, passive ECC injection, etc. It is designed to meet the fundamental safety requirements of safe shutdown, safe decay heat removal and confinement of activity with no impact in public domain, and hence, no need for emergency planning under all conceivable scenarios. This paper examines the role of the various passive safety systems in prevention and mitigation of severe plant conditions that may arise in event of multiple failures. For the purpose of demonstration of the effectiveness of its passive features, postulated scenarios on the lines of three major severe accidents in the history of nuclear power reactors are considered, namely; the Three Mile Island (TMI, Chernobyl and Fukushima accidents. Severe plant conditions along the lines of these scenarios are postulated to the extent conceivable in the reactor under consideration and analyzed using best estimate system thermal-hydraulics code RELAP5/Mod3.2. It is found that the various passive systems incorporated enable the reactor to tolerate the postulated accident conditions without causing severe plant conditions and core degradation.

  2. Terrestrial invertebrate population studies in the Chernobyl exclusion zone, Ukraine

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, D.; Stone, D.M. [Enviros, 61 The Shore, Leith, Edinburgh (United Kingdom); Copplestone, D.; Gilhen, M.C. [Liverpool Univ., Environmental Research and Consultancy (United Kingdom)

    2004-07-01

    The Chernobyl reactor accident in April 1986 caused the release to atmosphere of substantial amounts of radioactivity. Precise estimates of the release vary. The USSR State Committee presented information to a meeting of the International Atomic Energy Agency in August 1986 indicating a release of some 2.9x10{sup 5} TBq {sup 137}Cs and 2x10{sup 5} TBq {sup 90}Sr, with a total fission/activation product release of 1.7x10{sup 6} TBq. Other commentators suggest that up to double this amount may have been released. Estimates of deposition likewise vary, although it is probable that about half the released activity was deposited within 20 km of the release point, predominantly following two plume trajectories to the north and west. This resulted in the death of pine trees over 400 ha, the abandonment of 100,000 to 150,000 ha of agricultural land and the establishment of an exclusion zone extending to 30 km from the site. High levels of radionuclide contamination continue to prevail within the exclusion zone. Nonetheless, over the past fifteen years, re-colonisation has been widespread. Mixed deciduous woodlands, with a high proportion of birch (Betula spp.) and willow (Salix spp.), have become established in the forest areas, while agricultural land has succeeded to tall grassland and scrub. Field sites established in this study exhibited external gamma dose rates varying from 0.1 {mu}Sv h{sup -1} to 140 {mu}Sv h{sup -1}. Corresponding mean concentrations of {sup 137}Cs in the top 20 cm of soil varied from about 6.10{sup 2} to 3.10{sup 6} Bq kg{sup -1} dw. This study summarises observations over the period 2001 to 2004. Sub-surface activity, as measured by bait lamina penetration, appears to be inversely correlated with concentrations of {sup 137}Cs and {sup 90}Sr in soil. Likewise, at the very highest levels of contamination, there is some loss of invertebrate diversity; although little associated change in overall biomass. Between years, population densities and

  3. Investigation of radionuclides and anthropic tracer migration in groundwater at the Chernobyl site

    Science.gov (United States)

    Le Gal La Salle, Corinnne; Simonucci, Caroline; Roux, Céline; Bugai, Dmitry; Aquilina, Luc; Fourré, Elise; Jean-Baptiste, Philippe; Labasque, Thierry; Michelot, Jean-Luc; Fifield, Keith; Team Aster Team; Van Meir, Nathalie; Kashparov, Valeriy; Diez, Olivier; Bassot, Sylvain; Lancelot, Joel

    2013-04-01

    Following the reactor 4 explosion of the Chernobyl Nuclear Power Plant (ChNPP), at least 1019 Bq of radionuclides (RN) were released in the environment. In order to protect workers and prevent further atmospheric RN dispersion in the area adjacent to the ChNPP, contaminated wastes including fuel particles, topsoil layer and forest remains were buried in approximately 800 shallow trenches in the sand formation in the Red Forest waste dump site [1]. No containment measures were taken, and since then RN have leaked to the unsaturated zone and to the groundwater. Since 1999, migration of RN in the vicinity of the trench 22 at Red Forest site has been investigated within the frame of the EPIC program carried out by IRSN in collaboration with UIAR and IGS [2, 3]. A plume of 90Sr was shown downgradient from the trench 22 with activites reaching 3750 Bq/L [2]. In 2008, further studies were initiated through the TRASSE research group, based on a collaboration between IRSN and CNRS. These programs aim at combining groundwater dating with RN migration monitoring studies in order to constrain RN transport models [3]. Groundwater residence time was investigated based on 3H/He and CFC. Both tracers led to ages ranging from modern (1-3 y) at 2 m depth below the groundwater table to significantly higher apparent ages of 50-60 y at 27 m below the groundwater table [3]. 36Cl/Cl ratios 2 to 4 orders of magnitude higher than the theoretical natural ratio are measured in groundwater. Similarly, SF6 shows concentrations as high as 1200 pptv while natural concentrations are in the order of 6-7 pptv. Based on apparent groundwater ages, both contaminations are linked to the Chernobyl explosion. Hence those tracers show excellent potential to constrain conservative and reactive transport, respectively. In contrast, 238U/235U ratio down gradient from trench 22 remains similar to the natural ratio. This suggests that either most of the U contained in the trench is in a non soluble form

  4. A safety assessment of the use of graphite in nuclear reactors licensed by the US NRC

    Energy Technology Data Exchange (ETDEWEB)

    Schweitzer, D.G.; Gurinsky, D.H.; Kaplan, E.; Sastre, C.

    1987-09-01

    This report reviews existing literature and knowledge on graphite burning and on stored energy accumulation and releases in order to assess what role, if any, a stored energy release can have in initiating or contributing to hypothetical graphite burning scenarios in research reactors. It also addresses the question of graphite ignition and self-sustained combustion in the event of a loss-of-coolant accident (LOCA). The conditions necessary to initiate and maintain graphite burning are summarized and discussed. From analyses of existing information it is concluded that only stored energy accumulations and releases below the burning temperature (650/sup 0/C) are pertinent. After reviewing the existing knowledge on stored energy it is possible to show that stored energy releases do not occur spontaneously, and that the maximum stored energy that can be released from any reactor containing graphite is a very small fraction of the energy produced during the first few minutes of a burning incident. The conclusions from these analyses are that the potential to initiate or maintain a graphite burning incident is essentially independent of the stored energy in the graphite, and depends on other factors that are unique for these reactors, research reactors, and for Fort St. Vrain. In order to have self-sustained rapid graphite oxidation in any of these reactors, certain necessary conditions of geometry, temperature, oxygen supply, reaction product removal, and a favorable heat balance must be maintained. There is no new evidence associated with either the Windscale Accident or the Chernobyl Accident that indicates a credible potential for a graphite burning accident in any of the reactors considered in this review.

  5. 尿素合成塔内化学爆炸机理分析%Theoretical analysis on the urea reactor explosion accidents

    Institute of Scientific and Technical Information of China (English)

    李冬; 陶刚; 张礼敬; 许丹枫

    2011-01-01

    分析了尿素合成塔发生化学爆炸的可能性.利用经验公式计算出塔内上部空间气相在正常生产和非正常生产状态下的爆炸极限范围,并计算出非正常生产状态下气相化学爆炸产生的压力和能量范围.计算结果与现场数据吻合.爆炸所产生的压力作用于液面上,根据静压传递原理,尿液内各点与外压相等,超过尿塔正常工作压力,并导致破裂.%This paper intends to take as its two case study samples the two serious urea reactor explosion accidents that took place at home, which brought about heavy casualty and economic damage of similar nature. Thus, our analysis has been done in terms of three key elements of chemical explosions and their aftermath consequences. The analyses of the explosion process indicate that the flammable gases were found including hydrogen, ammonia and methane mixed with oxygen and inert gases, such as nitrogen, vapor and carbon dioxide in the gas phase of urea reactor. The impact friction, adiabatic compression, static and spontaneous combustion of such gases were found to be the ignition sources as the result of the analysis. Empirical equations were also used to confirm the explosion limit under the condition of high temperatures and high pressures.Moreover, conditions of inert gas presence was also taken into account. Everything considered, the explosion limit of mixed gases was found to be 11.27% - 78.94% under the normal production conditions. And the practical mixed gas concentration was found to be 92.19%, far above the explosion maximum limit. On the other hand, if the temperature decreased and the pressure remained in the maintenance range, and if the practical mixed gas concentration was within the explosion limit, it would also be possible to cause chemical explosions. When the urea reactor were shut down with its pressure maintained and the thermos level dropping, the volume of the gas phase would be likely to approach 3.7 m3. The

  6. Chernobyl-what do we need to know?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Following a succession of technical malfunctions and human errors, reactor No.4 of Chernobyl nuclear power plant explodes on April 26, 1986. Radioactive dust, aerosols, and gases (including iodine and caesium) are ejected into the atmosphere. The regions worst hit are in the immediate vicinity of the plant (Belarus, Ukraine) but deposits are very uneven, producing a 'leopard spot' type of pattern (Russian Federation). In Europe, propelled by easterly winds, the radioactive cloud disperses increasingly, scattering deposits over the whole Europe. At the beginning of May, the cloud arrives over France. The eastern portion of the country is most strongly affected. For the contamination, ground, water, and agriculture are contaminated by caesium deposits in Belarus, Ukraine and Russian Federation. In France, ground contamination is slight, fourteen years later, however, it is still detectable. It is hard to assess the impact on health in the vicinity of the Chernobyl plant; among children in southern Belarus, the number of thyroid cancers has risen one hundred-fold. The doses delivered in France represent generally less than 1% of the average annual dose from radioactivity of natural origin. But some of the doses received were higher. Today, the protective sarcophagus covering the damaged reactor is fragile. Reactor No.3, still in operation, continues to pose a risk but the shutdown is provide for december 2000. (N.C.)

  7. Hydrogen combustion in a flat semi-confined layer with respect to the Fukushima Daiichi accident

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, Mike, E-mail: kuznetsov@kit.edu [Karlsruhe Institute of Technology, 76131 Karlsruhe (Germany); Yanez, Jorge [Karlsruhe Institute of Technology, 76131 Karlsruhe (Germany); Grune, Joachim; Friedrich, Andreas [Pro-Science GmbH, 76275 Ettlingen (Germany); Jordan, Thomas [Karlsruhe Institute of Technology, 76131 Karlsruhe (Germany)

    2015-05-15

    Graphical abstract: - Highlights: • Critical conditions for flame propagation regimes in a layer geometry are analyzed. • Numerical simulation of hydrogen explosion reproduces real strength of shock waves. • From 80 to 200 kg of hydrogen were exploded during Fukushima (Unit I) accident. • A sonic deflagration with TNT equivalent of 800 kg was the most probable regime. - Abstract: Hydrogen accumulations at the top of a containment or reactor building may occur due to the interaction of molten corium and water followed by a severe accident of a nuclear reactor (TMI, Chernobyl, Fukushima Daiichi). The hydrogen that is released from the reactor accumulates usually as a stratified semi-confined layer of hydrogen–air mixture. A series of large scale experiments on hydrogen combustion and explosion in a semi-confined layer of uniform and non-uniform hydrogen–air mixtures in the presence of obstructions or without them was performed at the Karlsruhe Institute of Technology (KIT). Different flame propagation regimes from slow subsonic to relatively fast sonic flames and then to detonations were experimentally investigated in different geometries and then simulated with COM3D code with respect to evaluate the amount of hydrogen that was involved in the Fukushima Daiichi Accident (FDA). The experiments were performed in a horizontal semi-confined layer with the dimensions 9 × 3 × 0.6 m with/without obstacles opened from below. The hydrogen concentration in the mixtures with air was varied in the range of 10–34 vol.% without or with a gradient of 20–60 vol.%H{sub 2}/m. Effects of hydrogen concentration gradient, layer thickness, obstruction geometry, average and maximum hydrogen concentration on the flame propagation regimes were investigated with respect to evaluate the maximum pressure loads on internal structures. Blast wave strength and dynamics of propagation after the explosion of the hydrogen–air mixture layer were numerically simulated to reproduce

  8. Investigation on two-phase critical flow for loss-of-coolant accident of pressurized water reactor

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    The previous investigations were mainly conducted under the condition of low pressure,however,the steam-water specific volume and the interphase evaporation rate in high pressure are much different from those in low pressure,Therefore,the new experimental and theoretical investigation are performed in Xi'an Jiaotong University.The investigation results could be directly applied to the analysis of loss-of -coolant accident for pressurized water reacor.The system transition characteristics of cold leg and hot leg break loss-of -coolant tests are described for convective circulation test loop.Two types of loss-of-coolant accident are identified for :hot leg” break,while three types for “cold leg”break and the effect parameters on the break geometries.Tests indicate that the mass flow rate with convergent-divergent nozzle reaches the maximum value among the different break sections at the same inlet fluid condition because the fluid separation does not occur.A wall surface cavity nucleation model is developed for prediction of the critical mass flow rate with water flowing in convergentdivergent nozzles.

  9. Effect of Check Valve on Consequences of Coolant Pump Rotor Seizure Accident for EPR Reactor%止回阀对EPR反应堆主泵卡轴事故后果的影响

    Institute of Scientific and Technical Information of China (English)

    陈秋炀; 周拥辉

    2012-01-01

    分析计算欧洲先进压水堆(EPR)反应堆主泵卡轴事故,并对比在主泵出口安装止回阀和没有安装止回阀模型的卡轴事故安全分析.结果表明,在EPR主泵卡轴事故中,止回阀可增加模型堆芯进口流量约4%,有利于堆芯的冷却.止回阀可显著地提高堆芯最小偏离泡核沸腾比(DNBR),降低堆芯偏离泡核沸腾(DNB)份额,降低包壳温度约14℃.模型分析结果表明,在主泵卡轴事故工况下,主泵出口安装止回阀可更好地维持堆芯的完整性.%Counter current flow phenomenon would appear during reactor coolant pump rotor seizure accident. Present work analyzes the coolant pump rotor seizure accident for European Pressurized Reactor (EPR). The accident safety analysis results of model with check valve and without check valve are compared. It can be found that the check valve can increase the core inlet flow rate of model about 4%. The increasing of coolant flow rate is beneficial to the reactor core cooling. Check valve can increase the minimum departure from nucleate boiling ratio (DNBR), reduce the departure from nucleate boiling (DNB) fraction and the fuel rod cladding temperature about 14℃ during coolant pump rotor seizure accident. The analyses results show that the model with check valve can maintain the integrity of nuclear fuel rod effectively during reactor coolant pump rotor seizure accident.

  10. Chernobyl: the true, the possible and the false; TCHERNOBYL Le vrai, le probable et le faux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This report discusses the health consequences of the Chernobyl accident. It also highlights the misunderstanding associated with the use by the media of different radioactivity measurement units. It comments some figures about casualties, and the fact that some much higher figures are often stated. It evokes the issue of thyroid cancer in children of the region, discusses other possible public health consequences, the issue of congenital anomalies, the opinion of French physicists on the increase of thyroid cancers in France, and the question of the discrimination between spontaneous and radio-induced cancers. A second part discusses the risk of cancer and its perception in France: validity of the soil contamination assessment, possibility of an accident like Chernobyl and Fukushima in France

  11. ASTEC V2.0 reactor applications on French PWR 900 MWe accident sequences and comparison with MAAP4

    Energy Technology Data Exchange (ETDEWEB)

    Lombard, Virginie; Azarian, Garo; Ducousso, Erik; Gandrille, Pascal, E-mail: pascal.gandrille@areva.com

    2014-06-01

    In the frame of the SARNET Severe Accident Network of Excellence an important task of partners is the assessment of the ASTEC integral code, considered today as the European reference code for evaluation of the source term. A code-to-code comparison between ASTEC V2.0 rev1 and MAAP 4.0.7 code versions has been performed by AREVA NP SAS on a French PWR 900 MWe. Two transients have been analyzed, focussing on in-vessel phenomena: total loss of feedwater (H2 sequence in the French nomenclature) and total loss of onsite and offsite power (H3 sequence). The detailed analysis shows an overall good agreement between both code results on thermal-hydraulics, hydrogen production and core degradation phenomena.

  12. Non-thyroid cancer in Northern Ukr