カテゴリー「contamination and decontamination」
Title: Territory contamination with the radionuclides representing the fuel component of Chernobyl fallout
Author: V.A Kashparov, S.M Lundin, S.I Zvarych, V.I Yoshchenko, S.E Levchuk, Y.V Khomutinin, I.M Maloshtan, V.P Protsak
Reference: Science of The Total Environment, Volume 317, Issues 1–3, 30 December 2003, Pages 105-119
DOI: http://dx.doi.org/10.1016/S0048-9697(03)00336-X
Keywords: Chernobyl accident; Terrestrial density of contamination; Plutonium; Radioactive fallout; Fuel particles
Abstract: The data obtained through a series of experiments were used to specify the correlation of activities of the fuel component radionuclides of Chernobyl fallout and to create the maps of the 30-km Chernobyl zone terrestrial density of contamination with 154Eu, 238Pu, 239+240Pu and 241Am (on 01.01.2000). In the year 2000, total inventories of the fuel component radionuclides in the upper 30-cm soil layer of the 30-km Chernobyl zone in Ukraine (outside the ChNPP industrial site, excluding the activity located in the radioactive waste storages and in the cooling pond) were estimated as: 90Sr—7.7×1014 Bq; 137Cs—2.8×1015 Bq; 154Eu—1.4×1013 Bq; 238Pu—7.2×1012 Bq; 239+240Pu—1.5×1013 Bq; 241Am—1.8×1013 Bq. These values correspond to 0.4–0.5% of their amounts in the ChNPP unit 4 at the moment of the accident. The current estimate is 3 times lower than the previous widely-cited estimates. Inventories of the fuel component radionuclides were also estimated in other objects within the 30-km zone and outside it. This allowed more accurate data to be obtained on the magnitude of a relative release of radionuclides in the fuel particles (FP) matrix during the Chernobyl accident outside the ChNPP industrial site. It amounts to 1.5±0.5% of these radionuclides in the reactor, which is 2 times lower than the previous estimates. Two-thirds of the radionuclides release in the FP was deposited on the territory of Ukraine.
URL: http://www.sciencedirect.com/science/article/pii/S004896970300336X
Title: Transfer of radiocaesium in sensitive agricultural environments after the Chernobyl fallout in Sweden. II. Marginal and seminatural areas in the county of Jämtland
Author: Klas Rosén
Reference: Science of The Total Environment, Volume 182, Issues 1–3, 5 April 1996, Pages 135-145
DOI: http://dx.doi.org/10.1016/0048-9697(95)05059-0
Keywords: Radiocaesium; Grass; Fallout; Chernobyl; Contamination
Abstract: In 1986, two Chernobyl-affected areas in the county of Jämtland, a mountain area and a river valley area, were investigated as to radiocaesium behaviour and transfer to grass. The soil surface layer (0–10 cm) in 1986 and 1989 and grass samples in 1986–1994 were analysed on 9 temporary grassland sites and 8 permanent pasture sites, described individually. The aim of this investigation was to study the sensitivity of different soil types and the influence of normal farming practices, ploughing and K-fertilization on the caesium transfer, in short- and long-term perspectives after the Chernobyl fallout. As expected, the transfer of 137Cs to grass was usually higher on permanent pasture than on temporary grassland. For both types of grassland, however, there was a considerable but different change of transfer with years. The transfer to grass in the year of the fallout, 1986, depended to a large extent on the thickness and interception capacity of the grass sward. In the following years, it also depended on the caesium-fixing capacity to clay minerals, on K-fertilization and the reverse process of K removal by plant uptake. Ploughing down the contaminated surface layer and the mixing of caesium with mineral soil were effective in reducing the transfer. During the period 1986–1994, the transfer was reduced considerably, showing a range of (0.1–177.3 m2/kg d.w.) × 10−3. The calculated annual reduction halftime, Tar, increased with years after fallout. It is clearly shown that both countermeasures, ploughing and K-fertilization, are of potential value to decrease grass contamination. Where both measures were employed a reduction in the range of 78%–95% was recorded in the year after ploughing.
URL: http://www.sciencedirect.com/science/article/pii/0048969795050590
Title: Soil contamination with 90Sr in the near zone of the Chernobyl accident
Author: V.A Kashparov, S.M Lundin, Yu.V Khomutinin, S.P Kaminsky, S.E Levchuk, V.P Protsak, A.M Kadygrib, S.I Zvarich, V.I Yoschenko, J Tschiersch
Reference: Journal of Environmental Radioactivity, Volume 56, Issue 3, 2001, Pages 285-298
DOI: http://dx.doi.org/10.1016/S0265-931X(00)00207-1
Keywords: Soil contamination; 90Sr; Chernobyl; 30 km exclusion zone; Map
Abstract: Representative large-scale soil sampling on a regular grid of step width about 1 km was carried out for the first time in the near zone of the Chernobyl accident (radius 36 km). An integrated map of terrestrial 90Sr contamination density in the 30 km exclusion zone (scale 1 : 200,000) has been created from the analysed samples. Maps of the main agrochemical characteristics of the soils, which determine the fuel particle dissolution rates and the contamination of vegetation, were produced. The total contents of 90Sr on the ground surface of the 30 km zone in Ukraine (without the reactor site and the radioactive waste storages) was about 810 TBq (8.1×10+14 Bq) in 1997, which corresponds to 0.4–0.5% of the Chernobyl reactor inventory at the time of the accident. This assessment is 3–4 times lower than previous estimates.
URL: http://www.sciencedirect.com/science/article/pii/S0265931X00002071
Title: Remediation strategies for rural territories contaminated by the Chernobyl accident
Author: P. Jacob, S. Fesenko, S.K. Firsakova, I.A. Likhtarev, C. Schotola, R.M. Alexakhin, Y.M. Zhuchenko, L. Kovgan, N.I. Sanzharova, V. Ageyets
Reference: Journal of Environmental Radioactivity, Volume 56, Issues 1–2, 2001, Pages 51-76
DOI: http://dx.doi.org/10.1016/S0265-931X(01)00047-9
Keywords: Chernobyl accident;137Cs; Remediation; Contamination; Dose
Abstract: The objective of the present paper is to derive remediation strategies for rural settlements contaminated by the Chernobyl accident in which annual doses to a critical group still exceed 1 mSv. Extensive radioecological data have been collected for 70 contaminated settlements. A dose model based on these data resulted in estimates that are on average close to and a bit less than the official dose estimates (‘catalogue doses’) published by the responsible Ministries of Belarus, Russia and Ukraine. For eight remedial actions that can be applied on a large scale, effectiveness and costs have been assessed in light of their dependence on soil type, contamination level and on the degree of previous application of remedial actions. Remediation strategies were derived for each of the 70 settlements by choosing remedial actions with lowest costs per averted dose and with highest degree of acceptability among the farmers and local authorities until annual doses are assessed to fall below 1 mSv. The results were generalised to 11 contamination/internal-dose categories. The total numbers of rural inhabitants and privately owned cows in the three countries distributed over the categories were determined and predicted until the year 2015. Based on these data, costs and averted doses were derived for the whole affected population. The main results are (i) about 2000 Sv can be averted at relatively low costs, (ii) the emphasis on reducing external exposures should be increased, (iii) radical improvement of hay-land and meadows and application of Prussian blue to cows should be performed on a large scale if annual doses of 1 mSv are an aim to be achieved, (iv) additional remedial actions of importance are fertilising of potato fields, distribution of food monitors and restriction of mushroom consumption, and (v) for inhabitants of some settlements (in total about 8600) annual doses cannot be reduced below 1 mSv by the remedial actions considered.
URL: http://www.sciencedirect.com/science/article/pii/S0265931X01000479
Title: Levels and trends of radioactive contaminants in the Greenland environment
Author: Henning Dahlgaard, Mats Eriksson, Sven P. Nielsen, Hans Pauli Joensen
Reference: Science of the Total Environment. Sep2004, Vol. 331 Issue 1-3, p53-67. 15p.
DOI: http://dx.doi.org/10.1016/j.scitotenv.2004.03.023
Keywords: Caesium-137; Strontium-90; Technetium-99; Plutonium-239-240; Polonium-210; Greenland; Environmental radioactivity
Abstract: Levels of radioactive contaminants in various Greenland environments have been assessed during 1999–2001. The source of 137Cs, 90Sr and 239,240Pu in terrestrial and fresh water environments is mainly global fallout. In addition, the Chernobyl accident gave a small contribution of 137Cs. Reindeer and lamb contain the largest observed 137Cs concentrations in the terrestrial environment—up to 80 Bq kg−1 fresh weight have been observed in reindeer. Due to special environmental conditions, 137Cs is transferred to landlocked Arctic char with extremely high efficiency in South Greenland leading to concentrations up to 100 Bq kg−1 fresh weight. In these cases very long ecological half-lives are seen. Concentrations of 99Tc, 137Cs and 90Sr in seawater and in marine biota decrease in the order North-East Greenland and the coastal East Greenland current>South-West Greenland>Central West Greenland and North-West Greenland>Irmiger Sea∼Faroe Islands. The general large-scale oceanic circulation combined with European coastal discharges and previous contamination of the Arctic Ocean causes this.
URL: http://www.sciencedirect.com/science/article/pii/S0048969704002025
Title: Current development of the human and environmental contamination in the Bryansk-Gomel Spot after the Chernobyl accident.
Author: Hille, R / Hill, P / Heinemann, K / Ramzaev, V / Barkovski, A / Konoplia, V / Neth, R
Reference: Radiation and environmental biophysics, 39 (2), p.99-109, Jun 2000
Keywords: contamination, Bryansk-Gomel, soil, food
Abstract: Up to 1991, it was assumed that after the Chernobyl accident in 1986 the time development of radioactive contamination with regard to environment, foodstuff, and man would decrease due to migration processes in the soil, radioactive decay, and protective measures. This assumption was confirmed by all measurements in the first few years after the accident. Since 1991, however, a change in this development has been observed, as many measurements show stagnation or in some cases even an increase of foodstuff and human contamination. If normalised to an average local ground contamination, only a few groups of foodstuffs (e.g., potatoes) show a slight decrease in radioactivity. In this paper, the time development of radioactive contamination in the Bryansk-Gomel Spot on the basis of measurements since 1991 is presented. The consequences for long-term dose assessment are discussed.
URL: http://link.springer.com/journal/411
Title: Radiation contamination after the chernobyl nuclear accident and the effective dose received by the population of Croatia
Author: Lokobauer, Nevenka / Franić, Zdenko / Bauman, Alica / Maračić, Manda / Cesar, Dobroslav / Senčar, Jasminka
Reference: Journal of Environmental Radioactivity, 41 (2), p.137-146, Nov 1998
doi: 10.1016/S0265-931X(97)00006-4
Keywords: Radioactive contamination, Croatia, humans, 137Cs, 90Sr
Abstract: Because of the Chernobyl nuclear accident which led to enhanced deposition of all fission products, contamination of the human environment in the Republic of Croatia was much higher than in the previous two decades. The paper deals with the investigation of deposition and contamination by fission product radionuclides (137Cs and 90Sr, in particular), especially within the human food chain. Its aim was to determine differences in contamination levels resulting from the Chernobyl accident and from large-scale atmospheric nuclear weapon tests. For the year following the Chernobyl accident, the radiation doses received from external and internal exposures were estimated for 1-year old infants, children at the age of 10-years and adults. The corresponding annual effective doses were 1·49, 0·93 and 0·83 mSv, respectively. The paper also gives data on the yearly intakes of 137Cs and 90Sr in foods and the corresponding effective doses received by the population of Croatia over many years from the global fallout following nuclear weapons testing and the Chernobyl accident.
URL:http://www.franic.info/radovi/NLokobauer_Radiation_Contamination_after_Chernobyl.pdf
Title: Radioactive waste management and environmental contamination issues at the Chernobyl site.
Author: Napier, B A / Schmieman, E A / Voitsekovitch, O
Reference: Health physics, 93 (5), p.441-451, Nov 2007
doi: 10.1097/01.HP.0000279602.34009.e3
Keywords: contamination, Radioactive waste management, Chernobyl exclusion zone
Abstract: The destruction of the Unit 4 reactor at the Chernobyl Nuclear Power Plant resulted in the generation of radioactive contamination and radioactive waste at the site and in the surrounding area (referred to as the Exclusion Zone). In the course of remediation activities, large volumes of radioactive waste were generated and placed in temporary near-surface waste storage and disposal facilities. Trench and landfill type facilities were created from 1986-1987 in the Chernobyl Exclusion Zone at distances 0.5-15 km from the nuclear power plant site. This large number of facilities was established without proper design documentation, engineered barriers, or hydrogeological investigations and they do not meet contemporary waste-safety requirements. Immediately following the accident, a Shelter was constructed over the destroyed reactor; in addition to uncertainties in stability at the time of its construction, structural elements of the Shelter have degraded as a result of corrosion. The main potential hazard of the Shelter is a possible collapse of its top structures and release of radioactive dust into the environment. A New Safe Confinement (NSC) with a 100 y service life is planned to be built as a cover over the existing Shelter as a longer-term solution. The construction of the NSC will enable the dismantlement of the current Shelter, removal of highly radioactive, fuel-containing materials from Unit 4, and eventual decommissioning of the damaged reactor. More radioactive waste will be generated during NSC construction, possible Shelter dismantling, removal of fuel-containing materials, and decommissioning of Unit 4. The future development of the Exclusion Zone depends on the future strategy for converting Unit 4 into an ecologically safe system, i.e., the development of the NSC, the dismantlement of the current Shelter, removal of fuel-containing material, and eventual decommissioning of the accident site. To date, a broadly accepted strategy for radioactive waste management at the reactor site and in the Exclusion Zone, and especially for high level and long-lived waste, has not been developed.
URL: http://www.ncbi.nlm.nih.gov/pubmed/18049220?dopt=Abstract
Title: One decade after Chernobyl
Author (Corporate): International atomic energy agency (IAEA)
Reference: IAEA (International atomic energy agency), 1997
doi:
Keywords: international conference, consequences of the accident
Abstract: As a part of the Chernobyl Project, the project was initiated by the IAEA in 1995 after a proposal by Belarus to convene an international group of high level experts to review the information drawn from the long term environmental and social studies of the Chernobyl accident and its consequences. The study had been monitored by an International Advisory Committee under the project management of the Institut de protection et de sûreté nucléaire (IPSN), France. The project report based mainly on the studies, carried out by experts from Belarus, the Russian Federation and Ukraine during the period 1986-1995, was published as IAEA TECDOC-1240
URL: http://www-pub.iaea.org/MTCD/publications/PDF/te_1240_prn.pdf
Russian:
Title: Problems of Radioecology in forest. Forest. People. Chernobyl.
Author: V. A. Ipat’ev, E. F. Konoplya, V. F. Baginsky, B. I. Yakushev, I. I. Maradulin
Reference: Gomel, 2004
doi:
Keywords: forest ecology, soil decontamination, forestry, forest fires, Belorussia, Baltic countries, ground contamination
Abstract: Problems of safety system. Rehabilitation of forest land contaminated with radionuclides. Forest fires in contaminated areas: prevention, eradication and consequences. Management activities in contaminated areas. Monitoring, forecast and radiation monitoring of forest products. Reports from parliamentary assembly of the Union of Belarus and Russia.
URL: http://catalog.belal.by/cgi-bin/irbis64r_01/cgiirbis_64.exe?LNG=&C21COM=S&I21DBN=BELAL&P21DBN=BELAL&S21FMT=briefwebr&S21ALL=(%3C.%3EK%3D%D1%87%D0%B5%D1%80%D0%BD%D0%BE%D0%B1%D1%8B%D0%BB%D1%8C%3C.%3E)&Z21ID=&S21SRW=TIPVID&S21SRD=DOWN&S21STN=1&S21REF=5&S21CNR=20
Russian: Проблемы радиоэкологии леса. Лес. Человек. Чернобыль: Ипатьев В.А., Конопля Е.Ф., Багинский В.Ф., Якушев Б.И., Марадулин И.И. …
