Cadastral valuation of land contaminated with radionuclides

Science.gov (United States)

Ratnikov, A. N.; Sapozhnikov, P. M.; Sanzharova, N. I.; Sviridenko, D. G.; Zhigareva, T. L.; Popova, G. I.; Panov, A. V.; Kozlova, I. Yu.

2016-01-01

The methodology and procedure for cadastral valuation of land in the areas contaminated with radionuclides are presented. The efficiency of rehabilitation measures applied to decrease crop contamination to the levels satisfying sanitary-hygienic norms is discussed. The differentiation of cadastral value of radioactively contaminated agricultural lands for the particular farms and land plots is suggested. An example of cadastral valuation of agricultural land contaminated during the Chernobyl Nuclear Power Plant accident is given. It is shown that the use of sandy and loamy sandy soddy-podzolic soils with the 137Cs contamination of 37-185 and >185 kBq/m2 for crop growing is unfeasible. The growing of grain crops and potatoes on clay loamy soddy-podzolic soils with the 137Cs contamination of 555-740 kBq/m2 is unprofitable. The maximum cadastral value of radioactively contaminated lands is typical of leached chernozems.

Low-cost bioremediation of heavy metals and radionuclides of contaminated soils

International Nuclear Information System (INIS)

Sathiyamoorthy, P.; Golan-Goldhrish, A.

2005-01-01

The environmental pollution by toxic metals, especially lead (Pb), mercury (Hg), cadmium (Cd), nickel (Ni), copper (Cu), selenium (Se), chromium (Cr) and radionuclides ( 137 Cs, 90 Sr, 238 Pu, 226 Ra) is a potential hazard to health and welfare of mankind. Rapid industrial revolution has left an international legacy of soil and water contaminated with a combination of toxic and potentially carcinogenic compounds and heavy metals. Many of the contaminated sites were abandoned due to high cost of traditional clean-up approaches. Various approaches are being practiced to decontaminate heavy metals and radionuclides from polluted-soil. Remediation of heavy metal and radionuclides contaminated soils poses a significant expense to many industries and government organizations. Remediation cost in the United States and European Union alone is expected to exceed US$20 billion annually. Bioremediation strategy depends on the limitations of technology, cost and nature of the contaminant in the soil. Certain higher plants are capable of accumulation of heavy metals (2-5 %) in roots and shoots to the level far exceeding those present in the soils, these are called hyper-accumulators. Using heavy metal hyper-accumulating higher plants for environmental clean-up of contaminated soil is a recently emerged technology known as 'phytoremediation'. Genetically engineered (Transgenic) plants have a remarkable potential to absorb heavy metals and show a new avenue for biotechnology technique in Phytoremediation. The cost-effective approach of using heavy metal and radionuclide hyper-accumulators in phytoremediation is discussed. (author)

Methods for the calculation of derived working limits for surface contamination by low-toxicity radionuclides

International Nuclear Information System (INIS)

Gibson, J.A.B.; Wrixon, A.D.

1979-01-01

Surface contamination is often measured as an indication of the general spread of radioactive contamination in a particular place. Derived working limits, (DWLs) for surface contamination provide figures against which to assess the significance of measurements. Derived working limits for surface contamination were first established for use in the nuclear energy industry. They were designed to cope with a wide range of unspecified radionuclides and were therefore based on the assumption that the contamination was due to the presence of the most hazardous radionuclides, e.g. 90 Sr, 210 Pb, 226 Ra and 239 Pu. While this assumption may still be appropriate when the radionuclide mixture is unknown, there are now many specialized uses of particular low-toxicity radionuclides in universities, hospitals and general industry. If it is known that only a particular radionuclide is present, the general DWL can be replaced by a more specific value. The methods for calculating DWLs for some of the more commonly employed low-toxicity radionuclides are described. The exposure pathways considered are (a) external radiation of the skin and inhalation of airborne material from contaminated surfaces in active areas; (b) external irradiation of the skin and ingestion from contaminated skin. Some consideration is given to the effect of the revised dose equivalent limits in the most recent recommendations of ICRP. (author)

Radiation protection aspects of the trafficking radionuclides contaminated metal scrap

International Nuclear Information System (INIS)

Prouza, Z.

1999-01-01

This paper covers the legal base of the release in the environment of radionuclides containing materials and the radiation protection aspects of trafficking in radionuclides contaminated materials. Materials, substance and objects containing radionuclides or contaminated by them may be released into the environment, if they do not exceed values authorized by SONS (State Office of Nuclear Safety). Legislative measures should be taken against illicit trafficking of the nuclear material in all the areas. The creation of a sophisticated system for the control and regulation of all important radionuclides released into the environment should be based on the radiation protection limits, constraints, reference and exemption levels which are introduced in the legislative documents; the strong supervision of producers and users of the sealed sources by SONS side, in addition to the requirements of the licensing process of their sources; a complete data-base and information exchange system related to illicit trafficking in contaminated material; in this system all the authorities with jurisdiction should be involved. The responsibilities of the persons involved in metal scrap trafficking should include arrangement of appropriate monitoring, rules for transport of the metal scrap, an adequate measuring system to monitor metal scrap including monitoring to prevent processing or smelting of the radioactive material, control measures, etc. All of the above items of legislation are an important challenge for the Czech Republic. (author)

The speciation, stability, solubility and biodegradation of organic co-contaminant radionuclide complexes: A review

International Nuclear Information System (INIS)

Keith-Roach, Miranda J.

2008-01-01

The potential migration of radionuclides is of concern at contaminated land sites and, in the long term, waste repositories. Pathways of migration need to be characterised on a predictive level so that management decisions can be made with confidence. A pathway that is relatively poorly understood at present is radionuclide solubilisation due to complexation by organic complexing agents that are present in mixed radioactive wastes, and at radioactively contaminated land sites. Interactions of the complexing agents with radionuclides and the host environment, and the response to changes in the physicochemical conditions make their role far from simple to elucidate. In addition, chemical and biodegradation of the organic materials may be important. In this paper, key co-contaminant organics are reviewed with emphasis on their environmental fate and impact on radionuclide migration

The speciation, stability, solubility and biodegradation of organic co-contaminant radionuclide complexes: A review

Energy Technology Data Exchange (ETDEWEB)

Keith-Roach, Miranda J. [Biogeochemistry and Environmental Analytical Chemistry Group/Consolidated Radio-isotope Facility, School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)], E-mail: mkeith-roach@plymouth.ac.uk

2008-06-15

The potential migration of radionuclides is of concern at contaminated land sites and, in the long term, waste repositories. Pathways of migration need to be characterised on a predictive level so that management decisions can be made with confidence. A pathway that is relatively poorly understood at present is radionuclide solubilisation due to complexation by organic complexing agents that are present in mixed radioactive wastes, and at radioactively contaminated land sites. Interactions of the complexing agents with radionuclides and the host environment, and the response to changes in the physicochemical conditions make their role far from simple to elucidate. In addition, chemical and biodegradation of the organic materials may be important. In this paper, key co-contaminant organics are reviewed with emphasis on their environmental fate and impact on radionuclide migration.

The fate and importance of radionuclides produced in nuclear events

Energy Technology Data Exchange (ETDEWEB)

Shore, B; Anspaugh, L; Chertok, R; Gofman, J; Harrison, F; Heft, R; Koranda, J; Ng, Y; Phelps, P; Potter, G; Tamplin, A [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1969-07-01

Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

The fate and importance of radionuclides produced in nuclear events

International Nuclear Information System (INIS)

Shore, B.; Anspaugh, L.; Chertok, R.; Gofman, J.; Harrison, F.; Heft, R.; Koranda, J.; Ng, Y.; Phelps, P.; Potter, G.; Tamplin, A.

1969-01-01

Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

Chromatographic purification of neutron capture molybdenum-99 from cross-contaminant radionuclides

International Nuclear Information System (INIS)

Mostafa, M.A.M.

2011-01-01

Technetium-99m is called the work horse, for many reasons, in nuclear medicine diagnostic purposes. It is produced as the β - decay of 99 Mo radionuclide. Molybdenum-99 gel type generators are considered as a suitable alternative of the conventional chromatographic alumina columns loaded with fission molybdenum-99. 99 Mo neutron-capture is cross-contaminated with radionuclides originated from activation of chemical impurities in the Mo target such 60 C0, 65 Zn, 95 Zr, 175 Hf, 181 Hf, 86 Rb, 134 Cs, 141 Ce, 152 Eu, 140 La, 51 Cr, 124 Sb, 46 Sc, 54 Mn, 59 Fe and / or fast neutrons interactions with the stable isotopes of molybdenum such as 92m Nb, 95 Nb and 95 Zr. To prevent contamination of the eluted 99m Tc, successive purification methods were made. After complete dissolution of the irradiated target wrapped with thin Al foil in 5 M NaOH solution, hydrogen peroxide was added to start precipitation of Fe(OH) 3 . The formed Fe (III) minerals allow complete elimination of some radio contaminants from the molybdate solute such as 152 Eu, 140 La, 141 Ce, 45 Mn and 92m Nb in addition to partial elimination of 46 Sc, 60 Co and 59 Fe radionuclides. The remaining supernatant was acidified by concentrated nitric acid to ph 9.5 for precipitation of Al(OH) 3 with complete elimination of radio contaminants such as 95 Zr 175 Hf, 181 Hf, 65 Zn, 124 Sb, 51 Cr, 46 Sc, 60 Co and 59 Fe. 134 Cs and 86 Rb radionuclides were not affected by precipitation of Fe(OH) 3 or Al(OH) 3 . Chromatographic column of potassium nickel hexacyanoferrate (II) (KNHCF) has high affinity towards elimination of 134 Cs and 86 Rb radionuclides. Highly pure molybdate- 99 Mo solution was processed for preparation of zirconium molybdate gel generator with 99m Tc eluate of high radionuclidic, radiochemical and chemical purity suitable for use in medical purposes.

An analysis of nature and mechanisms of the Lira objects territories' radionuclide contamination

International Nuclear Information System (INIS)

Kadyrzhanov, K.K; Tuleushev, A.Zh.; Lukashenko, S.N.; Solodukhin, V.P.; Kazachevskij, I.V.; Reznikov, S.V.

2001-01-01

In the paper the results of study of radioactive contamination of 'Lira' objects territories are presented. Obtained data are evidencing, that existing radiation situation does not presents a threat for operating personnel of both the occupied on the deposit and its objects furthermore for inhabitants of the closest localities. Therewith a radionuclides concentration in the soils on the examined areas is slightly exceeds the background values characteristic for this region. Two hypothesises for reveled radionuclide contamination have been considered: yield on the surface and distribution by territory immediately after explosion 137 Xe and 90 Kr inert gases - they are genetical predecessors of 137 Cs and 90 Sr, relatively; existence of a constant effluence of these radionuclides on a surface from a 'ditch cavities' of the 'Lira' objects by the zones of dis-consolidation and crack propagations in the earth crust. With purpose for these hypothesis correctness clarification the distribution of radionuclides by soil layer depth in the vicinities of militant wells (TK-2 and TK-5), as well as in the case and riverbed of the Berezovka river. There are not data confirm the hypothesis about possible constant radionuclides influent from a 'ditch cavities'. So, the hypothesis of the 'Lira' objects territories radionuclide contamination due to inert gases yield on the surface is a more rightful

Allowable residual contamination levels of radionuclides in soil from pathway analysis

International Nuclear Information System (INIS)

Nyquist, J.E.; Baes, C.F. III

1987-01-01

The Remedial Action Program (RAP) at Oak Ridge National Laboratory will include well drilling, facility upgrades, and other waste management operations likely to involve soils contaminated with radionuclides. A preliminary protocol and generalized criteria for handling contaminated soils is needed to coordinate and plan RAP activities, but there exists only limited information on contaminate nature and distribution at ORNL RAP sites. Furthermore, projections of long-term decommissioning and closure options for these sites are preliminary. They have adapted a pathway analysis model, DECOM, to quantify risks to human health from radionuclides in soil and used it to outline preliminary criteria for determining the fate of contaminated soil produced during RAP activities. They assumed that the site could be available for unrestricted use immediately upon decontamination. The pathways considered are consumption of food grown on the contaminated soil, including direct ingestion of soil from poorly washed vegetables, direct radiation from the ground surface, inhalation of resuspended radioactive soil, and drinking water from a well drilled through or near the contaminated soil. We will discuss the assumptions and simplifications implicit in DECOM, the site-specific data required, and the results of initial calculations for the Oak Ridge Reservation

Consequences of hydrological events on the delivery of suspended sediment and associated radionuclides from the Rhone River to the Mediterranean Sea

Energy Technology Data Exchange (ETDEWEB)

Eyrolle, Frederique; Antonelli, Christelle; Ferrand, Emmanuelle [IRSN, Saint Paul Lez Durance (France). Pole Radioprotection environnement, dechets et crise, PRP-ENV, Service d' Etude et de Surveillance de la Radioactivite dans l' Environnement; Raimbault, Patrick [Institut Mediterraneen d' Oceanologie, OSU Pytheas, Marseille (France); Aubert, Dominique [CEFREM, Univ. de Perpignan Via Domitia CNRS UMR, Perpignan (France); Jacquet, Stephanie; Radakovitch, Olivier; Raccasi, Guillaume [Aix-Marseille Univ.-CNR-IRD-College de France, Aix en Provence (France); Charmasson, Sabine [IRSN, La Seyne sur mer (France). Pole Radioprotection, environnement, dechets et crise, PRP-ENV, Service d' Etude et de Surveillance de la Radioactivite dans l' Environnement; Gurriaran, Rodolfo [IRSN, Orsay (France). Pole Radioprotection, environnement, dechets et crise, PRP-ENV, Service de Traitement des echantillos et de Metrologie pour l' Environnement

2012-10-15

Almost 20 nuclear reactors are situated along the Rhone valley, representing Europe's largest concentration of nuclear power plants. The fate of suspended sediments and natural and artificial particle-bound radionuclides in relation to extreme hydrological events was assessed at the lower course of the Rhone River, which provides the main source of water and sediment inputs to the northwestern Mediterranean Sea. We sampled water at a high frequency over the period 2001-2008 and measured suspended particulate matter (SPM) loads and particle-bound natural and artificial radionuclide concentrations at the SORA observatory station in Arles, France. We monitored various hydrological events (either natural or anthropogenic origin) and characterize their influence on concentrations and fluxes. The relationship between SPM concentration and the very wide range of water discharges did not differ significantly from previous periods, indicating no significant shift in the average sediment delivery over the last 20 years. Unexpected hydrological events of anthropogenic origin, in particular those associated with flushing of reservoirs that are generally not captured by sampling strategies, were recorded and were shown to transfer significant additional sediment and associated contaminants towards the marine environment. Concentrations of anthropogenic radionuclides associated with sediment (i.e., {sup 137}Cs, {sup 60}Co, {sup 54}Mn, {sup 110m}Ag, and Pu isotopes) varied over two to three orders of magnitude during periods of low and moderate flow due to variations in the liquid release from nuclear facilities. Except for Pu isotopes, the concentrations of the various particle-bound radionuclides generally showed a decreasing trend with increasing discharge, revealing the geochemical or anthropogenic background values, and providing a useful flood fingerprint for this large fluvial system before its entry into the marine environment. Our approach produced key data on the

Regularities of food stuffs and ration contamination with radionuclide

International Nuclear Information System (INIS)

Barkhudarov, R.M.

1980-01-01

Modelling of the process of contamination of food stuffs and rations as a whole in the case of aerial and soil ways of administration of 90 Sr and 137 Cs long-living radionuclides is presented. A modified formula which takes into account radionuclide content in the soil in the previous year and levels of precipitation for 2 years is given. A modified equation of 137 Cs content in soils and fallouts expressed through the value of the initial stratospheric reservoir is given. It is shown that since 1972 137 Cs has come in the ration as a whole and in milk primarily through the aerial way, while 137 Cs has come in bread and bakery products by a soil way in a practically equal amount. The data presented are mean values in the country. 137 Cs contamination in recent years occurs mainly by the soil way

Modelling accumulation of radionuclides in terrestrial ecosystems originating from a long-term groundwater contamination

Energy Technology Data Exchange (ETDEWEB)

Gaerdenaes, Annemieke I. [Dept. of Soil and Environment, Swedish University of Agricultural Sciences (SLU), P.O. Box 7001, 750 07 Uppsala (Sweden); Eckersten, Henrik [Dept. of Ecology and Crop Production, SLU, P.O. Box 7042, 750 07 Uppsala (Sweden); Reinlert, Andre [Dept. of Physical Geography and Ecosystems Analysis, Lund University, 223 62 Lund (Sweden); MMT, Sven Kaellfelts Gata 11 SE 426 71 Vaestra Froelunda (Sweden); Gustafsson, David; Jansson, Per-Erik [Dept. Land and Water Resources, KTH, SE 100 44, Stockholm (Sweden); Ekstroem, Per-Anders [Facilia AB, Gustavlundsvaegen 151A, 167 51 Bromma (Sweden); Greger, Maria [Dept. of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm (Sweden)

2014-07-01

This study was conducted as part of the risk assessment of final deposits of nuclear fuel waste. The overall objective is to assess the possible accumulation of radionuclides in terrestrial ecosystems after an eventual long-term groundwater contamination. The specific objectives are to assess: i) What proportion of the contamination will accumulate in the soil-plant-system? ii) Where in the soil-plant- system will it accumulate? iii) Which ecosystem characteristics and radionuclides properties are important for the accumulation? and iv) Under which circumstances do losses from the ecosystems occur? We developed the dynamic model Tracey (Gaerdenaes et al. 2009) describing cycling of radionuclides in terrestrial ecosystems with high temporal resolution (1 day). The model is a multi-compartmental model in which fluxes and storage of radionuclides are described for different plant parts and soil pools in each of the 10 soil layers. The radionuclide fluxes are driven either by water or carbon fluxes. The water and the carbon fluxes are simulated with the dynamic, bio-geophysical Coup Model (Jansson and Karlberg, 2004). Tracey includes two root uptake approaches of radionuclides; (i) passive uptake driven by root water uptake and (ii) active uptake driven by plant growth. A linear approach describes the adsorption of radionuclides to soil particles and organic matter. Tracey was applied on two ecosystems with contrasting hydrology, the mixed Pinus-Picea forests found in the dry, elevated areas and the Alnus forests found in the wet, low-land areas of Uppland in central east Sweden. Different varieties of the two forest types were created by varying the root depth and radiation use efficiency. The climate was cold-temperate and based on 30-year daily weather data from Uppsala. The assumed groundwater contamination was close to 1 mg of an unspecified radionuclide per m2 and year. This load corresponds to 1 Bq per m{sup 2} and year of {sup 238}U, a common long

Study of radionuclide contamination at the former Semipalatinsk test site

International Nuclear Information System (INIS)

Artemyev, O.A.

2002-01-01

In the paper the contamination technical areas of the former Semipalatinsk test site is discussed in details. It is concluded, that radioactive contamination of the Degelen technical area caused by underground nuclear tests is mainly retained within tunnels and cavities. Investigation showed that many tunnel portal areas here are contaminated by radioactive substances. Areas of significantly high contamination levels are also found at the Balapan technical area mainly around borehole sleeves. A serious source of radioactive contamination is tritium in used boreholes and high content of radionuclides produced due to the fission of nuclear device and activation of rocks at crater rim around the Atom lake

Genotoxic endpoints in the earthworms sub-lethal assay to evaluate natural soils contaminated by metals and radionuclides

International Nuclear Information System (INIS)

Lourenco, Joana I.; Pereira, Ruth O.; Silva, Ana C.; Morgado, Jose M.; Carvalho, Fernando P.; Oliveira, Joao M.; Malta, Margarida P.; Paiva, Artur A.; Mendo, Sonia A.; Goncalves, Fernando J.

2011-01-01

Eisenia andrei was exposed, for 56 days, to a contaminated soil from an abandoned uranium mine and to the natural reference soil LUFA 2.2. The organisms were sampled after 0, 1, 2, 7, 14 and 56 days of exposure, to assess metals bioaccumulation, coelomocytes DNA integrity and cytotoxicity. Radionuclides bioaccumulation and growth were also determined at 0 h, 14 and 56 days of exposure. Results have shown the bioaccumulation of metals and radionuclides, as well as, growth reduction, DNA damages and cytotoxicity in earthworms exposed to contaminated soil. The usefulness of the comet assay and flow cytometry, to evaluate the toxicity of contaminants such as metals and radionuclides in earthworms are herein reported. We also demonstrated that DNA strand breakage and immune cells frequency are important endpoints to be employed in the earthworm reproduction assay, for the evaluation of soil geno and cytotoxicity, as part of the risk assessment of contaminated areas. This is the first study that integrates DNA damage and cytotoxicity evaluation, growth and bioaccumulation of metals and radionuclides in a sub lethal assay, for earthworms exposed to soil contaminated with metals and radionuclides.

Genotoxic endpoints in the earthworms sub-lethal assay to evaluate natural soils contaminated by metals and radionuclides

Energy Technology Data Exchange (ETDEWEB)

Lourenco, Joana I., E-mail: joanalourenco@ua.pt [CESAM and Departamento de Biologia, Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Pereira, Ruth O., E-mail: ruthp@ua.pt [CESAM and Departamento de Biologia, Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Silva, Ana C., E-mail: ana.cmj@ua.pt [CESAM and Departamento de Biologia, Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Morgado, Jose M., E-mail: jmtmorgado@gmail.com [Centro de Histocompatibilidade do Centro, Praceta Prof. Mota Pinto, Edificio S. Jeronimo, 4o piso, Apartado 9041, 3001-301 Coimbra (Portugal); Carvalho, Fernando P., E-mail: fernando.carvalho@itn.pt [Instituto Tecnologico Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Oliveira, Joao M., E-mail: joaomota@itn.pt [Instituto Tecnologico Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Malta, Margarida P., E-mail: margm@itn.pt [Instituto Tecnologico Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Paiva, Artur A., E-mail: apaiva@histocentro.min-saude.pt [Centro de Histocompatibilidade do Centro, Praceta Prof. Mota Pinto, Edificio S. Jeronimo, 4o piso, Apartado 9041, 3001-301 Coimbra (Portugal); Mendo, Sonia A., E-mail: smendo@ua.pt [CESAM and Departamento de Biologia, Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Goncalves, Fernando J., E-mail: fjmg@ua.pt [CESAM and Departamento de Biologia, Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal)

2011-02-15

Eisenia andrei was exposed, for 56 days, to a contaminated soil from an abandoned uranium mine and to the natural reference soil LUFA 2.2. The organisms were sampled after 0, 1, 2, 7, 14 and 56 days of exposure, to assess metals bioaccumulation, coelomocytes DNA integrity and cytotoxicity. Radionuclides bioaccumulation and growth were also determined at 0 h, 14 and 56 days of exposure. Results have shown the bioaccumulation of metals and radionuclides, as well as, growth reduction, DNA damages and cytotoxicity in earthworms exposed to contaminated soil. The usefulness of the comet assay and flow cytometry, to evaluate the toxicity of contaminants such as metals and radionuclides in earthworms are herein reported. We also demonstrated that DNA strand breakage and immune cells frequency are important endpoints to be employed in the earthworm reproduction assay, for the evaluation of soil geno and cytotoxicity, as part of the risk assessment of contaminated areas. This is the first study that integrates DNA damage and cytotoxicity evaluation, growth and bioaccumulation of metals and radionuclides in a sub lethal assay, for earthworms exposed to soil contaminated with metals and radionuclides.

Experimental and modelling studies of radionuclide migration from contaminated groundwaters

International Nuclear Information System (INIS)

Tompkins, J. A.; Butler, A. P.; Wheater, H. S.; Shaw, G.; Wadey, P.; Bell, J. N. B.

1994-01-01

Lysimeter-based studies of radionuclide uptake by winter wheat are being undertaken to investigate soil-to-plant transfer processes. A five year multi-disciplinary research project has concentrated on the upward migration of contaminants from near surface water-tables and their subsequent uptake by a winter wheat crop. A weighted transfer factor approach and a physically based modelling methodology, for the simulation and prediction of radionuclide uptake, have been developed which offer alternatives to the traditional transfer factor approach. Integrated hydrological and solute transport models are used to simulate contaminant movement and subsequent root uptake. This approach enables prediction of radionuclide transport for a wide range of soil, plant and radionuclide types. This paper presents simulated results of 22 Na plant uptake and soil activity profiles, which are verified with respect to lysimeter data. The results demonstrate that a simple modelling approach can describe the variability in radioactivity in both the harvested crop and the soil profile, without recourse to a large number of empirical parameters. The proposed modelling technique should be readily applicable to a range of scales and conditions, since it embodies an understanding of the underlying physical processes of the system. This work constitutes part of an ongoing research programme being undertaken by UK Nirex Ltd., to assess the long term safety of a deep level repository for low and intermediate level nuclear waste. (author)

Influence of predictive contamination to agricultural products due to dry and wet processes during an accidental release of radionuclides

International Nuclear Information System (INIS)

Hwang, Won Tae; Kim, Eun Han; Suh, Kyung Suk; Jeong, Hyo Joon; Han, Moon Hee; Lee, Chang Woo

2003-01-01

The influence of predictive contamination to agricultural products due to the wet processes as well as dry processes from radioactive air concentration during a nuclear emergency is comprehensively analyzed. The previous dynamic food chain model DYNACON considering Korean agricultural and environmental conditions, in which the initial input parameter was radionuclide concentrations on the ground, is improved so as to evaluate radioactive contamination to agricultural products from either radioactive air concentrations or radionuclide concentrations on the ground. As for the results, wet deposition is a more dominant mechanism than dry deposition in contamination on the ground. While, the contamination levels of agricultural products are strongly dependent on radionuclide and precipitation when the deposition of radionuclides occurs. It means that the contamination levels of agricultural products are determined from which is the more dominant process between deposition on the ground and interception to agricultural plants

Radionuclide contaminant analysis of small mammels, plants and sediments within Mortandad Canyon, 1994

International Nuclear Information System (INIS)

Bennett, K.; Biggs, J.; Fresquez, P.

1996-01-01

Small mammals, plants and sediments were sampled at one upstream location (Site 1) and two downstream locations (Site 2 and Site 3) from the National Pollution Discharge Elimination System outfall number-sign 051-051 in Mortandad Canyon, Los Alamos County, New Mexico. The purpose of the sampling was to identify radionuclides potentially present, to quantitatively estimate and compare the amount of radionuclide uptake at specific locations (Site 2 and Site 3) within Mortandad Canyon to an upstream site (Site 1), and to identify the primary mode (inhalation ingestion, or surface contact) of contamination to small mammals. Three composite samples of at least five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. In addition, three composite samples were also collected for plants and sediments at each site. Samples were analyzed for 241 Am, 90 Sr, 238 Pu, 239 Pu, and total U. With the exception of total U, all mean radionuclide concentrations in small mammal carcasses and sediments were significantly higher at Site 2 than Site 1 or Site 3. No differences were detected in the mean radionuclide concentration of plant samples between sites. However, some radionuclide concentrations found at all three sites were higher than regional background. No differences were found between mean carcass radionuclide concentrations and mean pelt radionuclide concentrations, indicating that the two primary modes of contamination may be equally occurring

Study of the contamination of components of the marine environment by soluble and insoluble forms of radionuclides

International Nuclear Information System (INIS)

Fraizier, A.; Ancellin, J.C.

1975-01-01

The experimental contamination of various physical components and organisms of the marine environment was carried out using radionuclides such as 137 Cs, 51 Cr, 60 Co, 106 Ru and 59 Fe. The relationships between the physico-chemical states of the radionuclides, the variations in the environmental conditions, and the properties of the experimental samples were clarified. Marine organisms were more readily contaminated by the insoluble forms of 106 Ru and 59 Fe than by the soluble forms. It appears that the physiology of the marine organisms can have a bearing on the degree and evolution of the contamination whatever the physico-chemical state of the radionuclides may be, but in certain circumstances the contamination level is independent of the variations in environmental conditions and the related variations in the physiology of the organism. (author)

About estimation of the contamination of territorial-administrative regions of the Chernobyl genesis radionuclides

International Nuclear Information System (INIS)

Berezhnoj, A.V.

2005-01-01

It is recommended to realize the matching territorial-administrative regions on degree of the contamination their of the Chernobyl genesis radionuclides to size generalised index gravity of the radionuclide soiling region. The methodology of the calculation indexes is offered. The results executed estimation are briefly stated. (authors)

Remediation of Deep Vadose Zone Radionuclide and Metal Contamination: Status and Issues

Energy Technology Data Exchange (ETDEWEB)

Dresel, P. Evan; Truex, Michael J.; Cantrell, Keri

2008-12-30

This report documents the results of a PNNL literature review to report on the state of maturity of deep vadose zone remediation technologies for metal contaminants including some radionuclides. Its recommendations feed into decisionmakers need for scientific information and cost-effective in situ remediation technlogies needed under DOE's Environmental Management initiative Enhanced Remediation Methods: Scientific & Technical Basis for In Stu Treatment Systems for Metals and Radionuclides.

Importance of initial management of persons internally contaminated with radionuclides

International Nuclear Information System (INIS)

Lincoln, T.A.

1975-01-01

The first one to three hours following a radiation accident during which internal contamination occurs provide the best and perhaps the only opportunity for preventing uptake of radionuclides. By using chemical manipulation in the GI tract or by hastening the material through the body, absorption can be reduced. Once absorbed, uptake in specific tissues can often be prevented by blocking agents, isotopic dilution or chelating agents. In order to supply prompt treatment, the medical department must have a well-defined action plan based on knowledge of the plant of laboratory operations, the radionuclides used, and medications required. (U.S.)

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

A model of accumulation of radionuclides in biosphere originating from groundwater contamination

International Nuclear Information System (INIS)

Gaerdenaes, Annemieke; Jansson, Per-Erik; Karlberg, Louise

2006-03-01

The objective of this study is to introduce a module in CoupModel describing the transport and accumulation in the biosphere of a radionuclide originating from a ground water contamination. Two model approaches describing the plant uptake of a radionuclide were included, namely passive and active uptake. Passive uptake means in this study that the root uptake rate of a radionuclide is governed by water uptake. Normal mechanism for the passive water uptake is the convective flux of water from the soil to the plant. An example of element taken up passively is Ca. Active plant uptake is in this model defined as the root uptake rate of a radionuclide that is governed by carbon assimilation i.e. photosynthesis and plant growth. The actively taken up element can for example be an element essential to plant, but not available in high enough concentration by passive uptake alone, like the major nutrients N and P or an element that very well resembles a plant nutrient, like Cs resembles K. Active uptake of trace element may occur alone or in addition to passive uptake. Normal mechanism for the active uptake is molecular diffusion from the soil solution to the roots or via any other organism living in symbiosis with the roots like the mycorrhiza. Also a model approach describing adsorption was introduced. CoupModel dynamically couples and simulates the flows of water, heat, carbon and nitrogen in the soil/plant/atmosphere system. Any number of plants may be defined and are divided into roots, leaves, stem and grain. The soil is considered in one vertical profile that may be represented into a maximum of 100 layers. The model is the windows-successor and integrated version of the DOS-models SOIL and SOILN, which have been widely used on different ecosystems and climate regions during 25 years time period. To this soil/plant/atmosphere model were introduced a module describing accumulation of a radionuclide in the biosphere originating from groundwater contamination. The

A model of accumulation of radionuclides in biosphere originating from groundwater contamination

Energy Technology Data Exchange (ETDEWEB)

Gaerdenaes, Annemieke [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Soil Sciences; Jansson, Per-Erik; Karlberg, Louise [Royal Inst. of Technology, Stockholm (Sweden). Dept. Land and Water Resources

2006-03-15

The objective of this study is to introduce a module in CoupModel describing the transport and accumulation in the biosphere of a radionuclide originating from a ground water contamination. Two model approaches describing the plant uptake of a radionuclide were included, namely passive and active uptake. Passive uptake means in this study that the root uptake rate of a radionuclide is governed by water uptake. Normal mechanism for the passive water uptake is the convective flux of water from the soil to the plant. An example of element taken up passively is Ca. Active plant uptake is in this model defined as the root uptake rate of a radionuclide that is governed by carbon assimilation i.e. photosynthesis and plant growth. The actively taken up element can for example be an element essential to plant, but not available in high enough concentration by passive uptake alone, like the major nutrients N and P or an element that very well resembles a plant nutrient, like Cs resembles K. Active uptake of trace element may occur alone or in addition to passive uptake. Normal mechanism for the active uptake is molecular diffusion from the soil solution to the roots or via any other organism living in symbiosis with the roots like the mycorrhiza. Also a model approach describing adsorption was introduced. CoupModel dynamically couples and simulates the flows of water, heat, carbon and nitrogen in the soil/plant/atmosphere system. Any number of plants may be defined and are divided into roots, leaves, stem and grain. The soil is considered in one vertical profile that may be represented into a maximum of 100 layers. The model is the windows-successor and integrated version of the DOS-models SOIL and SOILN, which have been widely used on different ecosystems and climate regions during 25 years time period. To this soil/plant/atmosphere model were introduced a module describing accumulation of a radionuclide in the biosphere originating from groundwater contamination. The

An assessment of flux of radionuclide contamination through the large Siberian rivers to the Kara sea

International Nuclear Information System (INIS)

Maderich, V.; Dziuba, N.; Koshebutsky, V.; Zheleznyak, M.; Volkov, V.

2004-01-01

The activities of several nuclear reprocessing plants (Siberian Chemical Combine (SCC) and Mining, Chemical Combine (MCC) and Mayak Production Association (Mayak)) that are placed in the watersheds of large Siberian rivers Ob' and Yenisey may potentially cause contamination of the Arctic Ocean. An assessment of the levels of radionuclide discharges into the Kara Sea from existing and potential sources of techno-genic radioactivity, located within the watershed of the Ob' and Yenisey rivers is presented. In frame of EU INCO-COPERNICUS project RADARC a linked chain of 1D river model RIVTOX and 3D estuary model THREETOX was used to simulate impact of the previous and potential releases from the nuclear installations in the basins of Ob' and Yenisey rivers on radioactive contamination of the rivers and the Kara Sea. The RIVTOX includes the one-dimensional model of river hydraulics, suspended sediment and radionuclide transport in river channels. THREETOX includes a set of submodels: a hydrodynamics sub-model, ice dynamics-thermodynamics sub-model, suspended sediment transport and radionuclide transport submodels. The radionuclide transport model simulate processes in water, suspended sediments and in bottom sediments. These models were adapted to the Ob' river path from Mayak and SCC and Yenisey River from MCC. The simulations of 90 Sr and 137 Cs contamination for the period 1949-1994 were carried out for the Ob' and period 1959-1994 for the Yenisey. The use of model chain allowed to reconstruct contamination of water and sediments along the river path to estimate fluxes into the Kara Sea. It was shown strong initial contamination in early 50's the sediments in the Ob' were sources for secondary contamination of river and estuary. Based on chosen realistic scenarios, simulations have been performed in order to assess the potential risk of contamination from existing and potential sources of radionuclides into the Kara Sea through the Ob' and Yenisey rivers. (author)

Phytoremediation of soils contaminated with toxic elements and radionuclides

International Nuclear Information System (INIS)

Cornish, J.E.; Goldberg, W.C.; Levine, R.S.; Benemann, J.R.

1995-01-01

At many US Department of Energy (US DOE) facilities and other sites, surface soils over relatively large areas are contaminated with heavy metals, radionuclides, and other toxic elements, often at only a relatively small factor above regulatory action levels. Cleanup of such sites presents major challenges, because currently available soil remediation technologies can be very expensive. In response, the US DOE's Office of Technology Development, through the Western Environmental Technology Office, is sponsoring research in the area of phytoremediation. Phytoremediation is an emerging technology that uses higher plants to transfer toxic elements and radionuclides from surface soils into aboveground biomass. Some plants, termed hyperaccumulators, take up toxic elements in substantial amounts, resulting in concentrations in aboveground biomass over 100 times those observed with conventional plants. After growth, the plant biomass is harvested, and the toxic elements are concentrated and reclaimed or disposed of. As growing, harvesting, and processing plant biomass is relatively inexpensive, phytoremediation can be a low-cost technology for remediation of extensive areas having lightly to moderately contaminated soils. This paper reviews the potential of hyper- and moderate accumulator plants in soil remediation, provides some comparative cost estimates, and outlines ongoing work initiated by the US DOE

Main reabilitation principles for forest lands, contaminated by radionuclides

International Nuclear Information System (INIS)

Borodastov, G.V.; Panfilov, A.V.; Ushakov, B.A.

1992-01-01

The reabilitation principles of radionuclide contaminated forest lands are proposed, based on the reabilitation experience in the thirty kilometer zone, on materials of researches and design and research, works of the enterprise Vozrozhdenie. The work is oriented on using in the higher and middle links of the organization structure. The feature of the reabilitation system is a complex approach to solution of the problem

Uptake of radionuclides by wheat roots with respect to location of contamination below the surface

International Nuclear Information System (INIS)

Suvornmongkhol, Narumon.

1996-01-01

The behaviour of 85 Sr, 137 Cs, 54 Mn and 60 Co in terms of plant availability in near surface soil and their root uptake was studied as a function of the location of contamination in the soil profile. Wheat (Triticum aestivum) was employed and the study programme involved both column and hydroponic studies. In the column studies, columns were packed with sandy soil, and either homogeneously or discretely contaminated with the radionuclides, and the water table maintained manually at 3 cm from the bottom. In the discrete contamination, the location of contamination was varied (0-5, 25-30 or 45-50 cm from the top). Wheat plants were grown to maturity in these columns, and harvested at different growth stages to examine radioactivity uptake and its subsequent translocation within the plants. The movement of radionuclides within the soil as well as the soil physicochemical properties were also investigated. The short term uptake kinetics of the hydroponically grown plants during ontogenesis were also studied, both with excised roots and intact plants. The excised root experiment was aimed at investigating the radionuclide by roots of different orders. (author)

Human dose pathways of radionuclides in forests

International Nuclear Information System (INIS)

Rantavaara, A.

2009-01-01

Forest soil, understorey vegetation and trees are all sources of radionuclides and human radiation doses after contaminating atmospheric deposition. People are exposed to radiation externally from sources outside the body and internally via ingestion and inhalation of radionuclides. Understorey vegetation contributes to ingestion doses through berries, herbs, wild honey, mushrooms and game meat; also trees provide feed to terrestrial birds and big game. During stay in forests people are subject to external radiation from forest floor and overstorey, and they may inhale airborne radioactive aerosol or gaseous radionuclides in ground level air. In the early phase of contamination also resuspended radionuclides may add to the internal dose of people via inhalation. People in Nordic countries are most exposed to radiation via ingestion of radionuclides in wild foods. The distribution of radionuclides in forests is changed by environmental processes, and thereby also the significance of various dose pathways to humans will change with time. External exposure is received in living environment from contaminated stemwood used as building timber and for manufacturing of furniture and other wood products. The aim of this paper is to outline the significance of various human dose pathways of radionuclides in forests considering the public and workers in forestry and production of bioenergy. Examples on effective doses are given based on two historical events, atmospheric nuclear weapon tests (mostly in 1950's and in 1960's) and the Chernobyl nuclear power plant accident in 1986. (au)

Influence of plant roots upon the mobility of radionuclides in soil, with respect to location of contamination below the surface

International Nuclear Information System (INIS)

Harvey, N.W.; Shaw, G.; Bell, N.J.B.

1997-01-01

The movement of 85 Sr, 137 Cs, 54 Mn and 60 Co in the 50 cm soil profile was studied with and without the presence of plant roots (triticum aestivum) in order to investigate the influence of roots and depth contamination upon the migration of radionuclides. The water table was maintained manually at 3 cm from the bottom. The physicochemical characteristics (E h Fe -2 , NH 4 + , pH and moisture content) as well as the total and extractable radioactivity were investigated. In the discrete contamination, where the location of contamination varied within the soil profile (0-5, 25-30 or 45-50 cm from the top), the influence of location upon the movement of these radionuclides was also studied. It was found that the changes in the soil physicochemical characteristics influenced the mobility of the four radionuclides. The extractability of 54 Mn and 60 Co was significantly increased in the reducing region of the soil, whereas that of 85 Sr, 137 Cs was not. Plant roots excerted significant effects upon the soil characteristics, via, reducing the E h pH and moisture content of the soil; increasing the extractability of both 54 Mn and 60 Co from the depth of 35 cm downwards. Radionuclide migration occurred via physicochemical and biological transport. The biological transport via plant roots was of particular importance for 137 Cs. Location of contamination had a significant influence upon the mobility of radionuclides. The migration of radionuclides was in the sequence of contamination in middle > bottom > top. The degree of the influence varied with radionuclides concerned. In the top layer contamination, the rank of the migration from the contamination layers, on the other hand 54 Mn, 60 Co and 137 Cs were more mobile and the movement was: 85 Sr ∼ 54 Mn ∼ 60 Co > 137 Cs. In the middle and bottom contamination layers, on the other hand, 54 Mn and 60 Co and 137 Cs were more mobile and the movement was 85 Sr ∼ 54 Mn ∼ 60 Co ∼ 137 Cs. (author)

Phytoremediation of soils and water contaminated with toxic elements and radionuclides

International Nuclear Information System (INIS)

Cornish, J.E.; Huddleston, G.J.; Levine, R.S.

1995-01-01

At many U.S. Department of Energy (DOE) facilities and other sites, large volumes of soils, sediments and waters are contaminated with heavy metals and/or radionuclides, often at only a relatively small factor above regulatory action levels. In response, the DOE's Office of Technology Development is evaluating the emerging biotechnology known as phytoremediation; this approach utilizes the accelerated transfer of contaminant mass from solution to either root or above ground biomass. After growth, the plant biomass - containing 100 to 1,000 times the contaminant levels observed with conventional plants - is processed to achieve further volume reduction and contaminant concentration. Thus, phytoremediation offers the potential for low cost remediation of highly to moderately contaminated media. Progress made to date by DOE in developing this technology will be summarized and evaluated

Radionuclide data analysis in connection of DPRK event in May 2009

Science.gov (United States)

Nikkinen, Mika; Becker, Andreas; Zähringer, Matthias; Polphong, Pornsri; Pires, Carla; Assef, Thierry; Han, Dongmei

2010-05-01

The seismic event detected in DPRK on 25.5.2009 was triggering a series of actions within CTBTO/PTS to ensure its preparedness to detect any radionuclide emissions possibly linked with the event. Despite meticulous work to detect and verify, traces linked to the DPRK event were not found. After three weeks of high alert the PTS resumed back to normal operational routine. This case illuminates the importance of objectivity and procedural approach in the data evaluation. All the data coming from particulate and noble gas stations were evaluated daily, some of the samples even outside of office hours and during the weekends. Standard procedures were used to determine the network detection thresholds of the key (CTBT relevant) radionuclides achieved across the DPRK event area and for the assessment of radionuclides typically occurring at IMS stations (background history). Noble gas system has sometimes detections that are typical for the sites due to legitimate non-nuclear test related activities. Therefore, set of hypothesis were used to see if the detection is consistent with event time and location through atmospheric transport modelling. Also the consistency of event timing and isotopic ratios was used in the evaluation work. As a result it was concluded that if even 1/1000 of noble gasses from a nuclear detonation would had leaked, the IMS system would not had problems to detect it. This case also showed the importance of on-site inspections to verify the nuclear traces of possible tests.

Initial site characterization and evaluation of radionuclide contaminated soil waste burial grounds

International Nuclear Information System (INIS)

Phillips, S.J.; Reisenauer, A.E.; Rickard, W.H.; Sandness, G.A.

1977-02-01

A survey of historical records and literature containing information on the contents of 300 Area and North Burial Grounds was completed. Existing records of radioactive waste location, type, and quantity within each burial ground facility were obtained and distributed to cooperating investigators. A study was then initiated to evaluate geophysical exploration techniques for mapping buried waste materials, waste containers, and trench boundaries. Results indicate that a combination of ground penetrating radar, magnetometer, metal detector, and acoustic measurements will be effective but will require further study, hardware development, and field testing. Drilling techniques for recovering radionuclide-contaminated materials and sediment cores were developed and tested. Laboratory sediment characterization and fluid transport and monitoring analyses were begun by installation of in situ transducers at the 300 North Burial Ground site. Biological transport mechanisms that control radionuclide movement at contaminated sites were also studied. Flora and fauna presently inhabiting specific burial ground areas were identified and analyzed. Future monitoring of specific mammal populations will permit determination of dose rate and pathways of contaminated materials contained in and adjacent to burial ground sites

Effects of radionuclide contamination on forest trees in the exclusion zone around the Fukushima Daiichi Nuclear Power Plant

International Nuclear Information System (INIS)

Watanabe, Yoshito; Kubota, Yoshihisa; Fuma, Shoichi; Yoshida, Satoshi; Ichikawa, San'ei; Kubota, Masahide; Takano, Toshiyuki; Mizoguchi, Masahiko

2012-01-01

A preliminary survey was performed for forest areas within the exclusion zone around the Fukushima Daiichi Nuclear Power Plant, for radionuclide contamination levels and radiation effects on trees during the first year after the March 2011 accident. Even in the most contaminated forest, approximately 3 km west of the power plant, no externally visible symptoms of radiation damage—including yellowing, malformation, and early withering of leaves—were observed in trees, indicating that massive radiation damage did not occur in the surrounding forests after the accident. Radiosensitive coniferous plants were, however, heavily contaminated by the deposition of radionuclides in reproductive organs such as cones, which could cause the exposure of developing seeds. The level of radionuclides in the cones of Japanese cedar trees changed, depending on the contamination level of the forest, which was approximately given by an ambient dose rate. The dose rate of internal exposure in the cones of the most contaminated forest, which was calculated to include exposure from the radionuclides deposited in the organs, was found to be within the criteria dose rate of 4-40 μGy/h selected for pine trees by the ICRP in Publication 108. This raises the necessity of performing more detailed analyses of the cytogenetic and reproductive damage to forest trees in the area. (author)

Effects of radionuclide contamination on forest trees in the exclusion zone around the Fukushima Daiichi Nuclear Power Plant

International Nuclear Information System (INIS)

Watanabe, Yoshito; Kubota, Yoshihisa; Fuma, Shoichi; Yoshida, Satoshi; Ichikawa, San'ei; Kubota, Masahide; Takano, Toshiyuki; Mizoguchi, Masahiko

2013-01-01

A preliminary survey was performed for forest areas within the exclusion zone around the Fukushima Daiichi Nuclear Power Plant, for radionuclide contamination levels and radiation effects on trees during the first year after the March 2011 accident. Even in the most contaminated forest, approximately 3 km west of the power plant, no externally visible symptoms of radiation damage—including yellowing, malformation, and early withering of leaves—were observed in trees, indicating that massive radiation damage did not occur in the surrounding forests after the accident. Radiosensitive coniferous plants were, however, heavily contaminated by the deposition of radionuclides in reproductive organs such as cones, which could cause the exposure of developing seeds. The level of radionuclides in the cones of Japanese cedar trees changed, depending on the contamination level of the forest, which was approximately given by an ambient dose rate. The dose rate of internal exposure in the cones of the most contaminated forest, which was calculated to include exposure from the radionuclides deposited in the organs, was found to be within the criteria dose rate of 4-40 μGy/h selected for pine trees by the ICRP in Publication 108. This raises the necessity of performing more detailed analyses of the cytogenetic and reproductive damage to forest trees in the area. (author)

Radionuclide deflation effects at contaminated environmental area in case of single and steady discharges to the atmosphere

International Nuclear Information System (INIS)

Makhon'ko, K.P.

1984-01-01

The effects of wind generation of radioactive dust in the area contaminated as a result of single or steady radionuclide discharges to the atmosphere are considered. Calculations are given on changing in time of the deflation coefficient Ksub(α) cm -1 on the base of the radionuclides migration rate account into the depth from a surface dust-forming soil layer and irradiation dose for account of radionuclides penetrated by food chains and into respiratory organs as a result of dusting of the contaminated zone. It is shown that the deflation effects play an essential part in case of emergency discharges owing to the possibility of including radionuclides in food chains through plants. The numerical calculations are performed for 90 Sr and 137 Cs and for light and heavy natural deposit soils

Artificial environmental radionuclides in Europe and methods of lowering their foodstuff contamination – a review

Directory of Open Access Journals (Sweden)

Katarína Beňová

2016-01-01

Full Text Available This review discusses the consequences of the food chain contamination with radionuclides, especially focusing on the radiocaesium impact after the Chernobyl nuclear accident. In particular, the 137Cs isotope still represents a risk. Until present it is still detectable in the meat of game animals, especially in wild boar, but also in elk and reindeer. Although the occurrence of highly contaminated foods in most of Europe is currently limited, along the German-Czech border (the Šumava Region the activity concentration of the 137Cs isotope in the meat of wild boar exceeds the acceptable limit several times. Additionally, the article describes simple processing technologies (cooking, pickling etc. that lead to reduction of radionuclides in contaminated food.

Chemical removal of radionuclides in contaminated spinach derived from the Fukushima nuclear accident

International Nuclear Information System (INIS)

Shiba, Kazuhiro; Kitamura, Yoji; Kozaka, Takashi; Uno, Izumi; Miyoshi, Hirokazu; Yanaga, Makoto

2012-01-01

We examined a simple and effective removal method for contaminated farm products to ensure the relief of farmers and the security of consumers. Removal of radionuclides from spinach by chemical methods was investigated. The result of chemical removal showed that antioxidant agents removed radionuclides from spinach by 70–80% for 131 I and more than 80% for radiocesium. In particular, ascorbic acid is promising as a safe and versatile option. (author)

Genetics of radionuclide-contaminated mosquitofish populations and homology between Gambusia affinis and G. holbrooki

International Nuclear Information System (INIS)

Theodorakis, C.W.; Bickham, J.W.; Chesser, R.K.

1998-01-01

The effects of radionuclide contamination on genetic structure of eastern mosquitofish (Gambusia holbrooki) populations from the US Department of Energy's Savannah River Site (SRS) were investigated to develop methods of assessing ecological risk of chronic exposures to xenobiotics. Fish from two contaminated and two reference sites were examined by the randomly amplified polymorphic DNA (RAPD) technique, which revealed that the frequency of three markers was greater in the contaminated than the reference sites and that the frequency of two markers was greater in reference than in the contaminated sites. A previous study examined populations of western mosquitofish (G. affinis) from the Oak Ridge National Laboratory (ORNL) and found that certain RAPD markers were present in radionuclide-contaminated ORNL populations at a higher frequency than in reference populations. The contaminant-indicative markers observed in the SRS populations were the same size and amplified by the same polymerase chain reaction primers used in the ORNL study. Southern blot analysis revealed that the SRS G. holbrooki contaminant-indicative markers were homologous to the ORNL G. affinis contaminant-indicative markers. The observation that two species show similar patterns of band frequency shifts at two separate localities is consistent with the hypothesis that these DNA markers may originate from genetic elements that provide a selective advantage in contaminated habitats. Thus, the methodology used in these studies may prove to be useful to indicate population-level effects of environmental contamination

Secondary contamination of 30-km zone of the Chernobyl atomic electric plant and adjacent territory due to radionuclides carried by ascending wind

International Nuclear Information System (INIS)

Garger, E.K.; Gavrilov, V.P.

1992-01-01

The territory contaminated with radionuclides as a result of the accident at the Chernobyl atomic electric plant is a surface source of radioactive aerosols carried into the atmosphere by ascending winds. In this connection, a number of problems arise whose solution is important for assessment of the radiation conditions in the atmosphere near the Earth's surface: (1) calculation of the volume concentration of radionuclides and their fallout on the contaminated and neighboring territory and on this basis determine the potentially dangerous contaminated regions; (2) assessment of the secondary contamination of deactivated territories due to ascending winds and transfer of radionuclides; and (3) determination of the size of the protective (buffer) zones around or near populated areas to ensure low volume concentrations of radionuclides during strong winds. In order to calculate the transfer of radionuclides from a surface source, it is necessary to know its dust intensity, which is the vertical turbulent flux of the radionuclides in the atmosphere layer near the ground Q (Ci · m -2 sec -1 ). A quantity frequently used in practice is Q referred to the contamination density of the surface layer c (Ci/m 2 ) and called the wind ascent intensity α = Q/c. As a rule, the radionuclide wind ascent intensity for a plane source with a nonuniform surface and contamination density may depend on the physical characteristics of the surface as well as on those of the radionuclides and also on the space coordinates x, y and on time. In the present study, the wind ascent intensity was determined by gradient measurements of the mean radionuclide concentration, the wind velocity and air temperature; the conditions during the measurements were assumed to correspond to the case of a plane homogeneous, stationary source of a nondepositing admixture

Effect of Some Therapeutic Agents on the Radionuclides Excretion from Internally Contaminated Rats

International Nuclear Information System (INIS)

Aziz, M.; Mangood, Sh.A.; Sohsah, M.A.

2009-01-01

The present work was oriented to investigate the effectiveness of Prussian blue (PB), vermiculite and diethylenetriaminepentaacetic acid (CaDTPA) as therapeutic agents for the elimination of either 134 Cs or 60 Co from contaminated rats after intake of one of the isotopes. The study was performed by using 48 adult rats divided into 8 identical groups each of six rats having approximately the same body weight. The groups included a reference group, without isotope or therapeutic agent administration, four groups given one of the isotopes and four groups given the isotopes and treated with different therapeutic regimes. The isotope content of the treated and untreated contaminated rats were followed by daily whole body radiometric counting for three weeks. On plotting log % radionuclide retained as a function of time, elapsed between radionuclide administration and radiometric counting, straight lines were obtained. The results indicate that excretion can mostly be represented by two stages; the first is fast followed by a second slow stage. The % radionuclide excreted, the corresponding rate constant and the biological half-life of each stage was estimated. It was found that the application of PB + vermiculite is more efficient, to remove 134 Cs, from contaminated rats, than PB only and CaDTPA is more efficient to remove 60Co. Therefore, it is recommended to use the three therapeutic agents to remove both isotopes when taken simultaneously

Use of dual-head gamma camera in radionuclide internal contamination monitoring on radiation workers from a nuclear medicine department

International Nuclear Information System (INIS)

Rodriguez-Laguna, A.; Brandan, M.E.

2008-01-01

As a part of an internal dosimetry program that is performed at the Mexican National Institute of Cancerology - Nuclear Medicine Department, in the present work we suggest a procedure for the routinely monitoring of internal contamination on radiation workers and nuclear medicine staff. The procedure is based on the identification and quantification of contaminating radionuclides in human body by using a dual-head whole-body gamma camera. The results have shown that the procedures described in this study can be used to implement a method to quantify minimal accumulated activity in the main human organs to evaluate internal contamination with radionuclides. The high sensitivity of the uncollimated gamma camera is advantageous for the routinely detection and identification of small activities of internal contamination. But, the null spatial resolution makes impossible the definition of contaminated region of interest. Then, the use of collimators is necessary to the quantification of incorporated radionuclides activities in the main human organs and for the internal doses assessment. (author)

Determination of correlation and scaling factors of radionuclides in the contaminated soils from experimental lysimetric field

International Nuclear Information System (INIS)

Dulanska, S.

2009-04-01

Correlation and regression analyses are often confused in evaluations of experimental results. However, the correlation analysis describes the influence of one variable level changes to changes of the other variable levels and holds for the variables measured quantitatively. It detects the existence and nature of dependencies, measures the goodness-of-fit of an actual model and tests the hypotheses of statistical significance of the model proposed. The y variable does not depend on the x variable but two random variables, x and y, vary jointly. The regression model, however, takes the independent variable x as a non-random variable and the dependent variable y as a random one, in contrast to the correlation model. There are a number of common difficulties associated with real datasets. The first involves the detection and elimination of outliers in the original data. We think of data as being divided into two classes (1) good observations (the majority of data) reflecting population scatter of data and (2) the outliers (if any) being a part of the so-called influential fatal points or noise. The goal of any outlier detection is to find this true partition and, thus, separate good from outlying observations. Regression diagnostics represent procedures for an examination of the regression triplet (data, model, method) for identification of (a) the data quality for a proposed model; (b) the model quality for a given set of data; (c) a fulfillment of all least-squares assumptions. Scheme and statistical evaluation of suitable scaling models for the monitoring of observed radionuclides 241 Am, 238 Pu and 239 , 240 Pu in real contaminated soils of experimental lysimetric field on the basis of experimental results were the objectives. Suitable scaling models for 241 Am, 238 Pu and 239 , 240 Pu radionuclide monitoring in contaminated soil samples placed in an experimental lysimeter have been proven by a regression triplet analysis. Estimates of and parameters for all

The uses of bioindicators in radionuclide contamination assessment

International Nuclear Information System (INIS)

McGee, E. J.; McGarry, A.

1994-01-01

This paper is a brief review and discussion of some approaches to sampling using bioindicators that have been employed in the assessment of radionuclide contamination in Ireland. Studies by other researchers are also referred to and the fields of research in radioecology where the use of bioindicators could be further developed are discussed. The review includes a discussion of the important attributes of bioindicators and how they can best be used in the development of effective but economical sampling strategies that yield the maximum amount of information. (author)

An electrochemical approach for removal of radionuclidic contaminants of Eu from 153Sm for effective use in metastatic bone pain palliation.

Science.gov (United States)

Chakravarty, Rubel; Chakraborty, Sudipta; Khan, Mohammed Sahiralam; Ram, Ramu; Sarma, Haladhar Dev; Dash, Ashutosh

2018-03-01

Thermal neutron activation of 152 Sm [ 152 Sm(n,γ) 153 Sm] using natural or isotopically enriched (by 152 Sm) samarium target is the established route for production of 153 Sm used for preparation of 153 Sm-EDTMP for pain palliation in cancer patients with disseminated bone metastases. However, some long-lived radionuclidic contaminants of Eu, such as, 154 Eu (t ½ =8.6y) are also produced during the target activation process. This leads to detectable amount of Eu radionuclidic contaminants in patients' skeleton even years after administration with therapeutic doses of 153 Sm-EDTMP. Further, the presence of such contaminants in 153 Sm raises concerns related to radioactive waste management. The aim of the present study was to develop and demonstrate a viable method for large-scale purification of 153 Sm from radionuclidic contaminants of Eu. A radiochemical separation procedure adopting electroamalgamation approach has been critically evaluated. The influence of different experimental parameters for the quantitative removal radionuclidic contaminants of Eu from 153 Sm was investigated and optimized. The effectiveness of the method was demonstrated by purification of ~37 GBq of 153 Sm in several batches. As a proof of concept, 153 Sm-EDTMP was administered in normal Wistar rats and ex vivo γ-spectrometry of bone samples were carried out. After carrying out the electrolysis under the optimized conditions, the radionuclidic contaminants of Eu could not be detected in purified 153 Sm solution by γ-spectrometry. The overall yield of 153 Sm obtained after the purification process was >85%. The reliability of this approach was amply demonstrated in several batches, wherein the performance remained consistent. Ex vivo γ-spectrometry of bone samples of Wistar rats administered with 153 Sm-EDTMP (prepared using electrochemically purified 153 Sm) did not show photo peaks corresponding to radionuclidic contaminants of Eu. A viable electrochemical strategy for the large

Risk-based screening analysis of ground water contaminated by radionuclides introduced at the Nevada Test Site (NTS)

International Nuclear Information System (INIS)

Daniels, J.I.; Anspaugh, L.R.; Andricevic, R.; Jacobson, R.L.

1993-06-01

The Nevada Test Site (NTS) is located in the southwestern part of Nevada, about 105 km (65 mi) northwest of the city of Las Vegas. Underground tests of nuclear weapons devices have been conducted at the NTS since late 1962 and ground water beneath the NTS has been contaminated with radionuclides produced by these tests. This concern prompted this examination of the potential health risk to these individuals from drinking the contaminated ground water either at a location on the NTS (assuming loss of institutional control after 100 y) or at one offsite (considering groundwater migration). For the purpose of this assessment, a representative mix of the radionuclides of importance and their concentrations in ground water beneath the NTS were identified from measurements of radionuclide concentrations in groundwater samples-of-opportunity collected at the NTS. Transport of radionuclide-contaminated ground water offsite was evaluated using a travel-time-transport approach. At both locations of interest, potential human-health risk was calculated for an individual ingesting radionuclide-contaminated ground water over the course of a 70-y lifetime. Uncertainties about human physiological attributes, as well as about estimates of physical detriment per unit of radioactive material, were quantified and incorporated into the estimates of risk. The maximum potential excess lifetime risk of cancer mortality estimated for an individual at the offsite location ranges from 7 x 10 -7 to 1 x 10 -5 , and at the onsite location ranges from 3 x 10 -3 to 2 x 10 -2 . Both the offsite and the onsite estimates of risk are dominated by the lifetime doses from tritium. For the assessment of radionuclides in ground water, the critical uncertainty is their concentration today under the entire NTS

Determination of the radionuclide contamination on the Absheron peninsula in Azerbaijan - 59177

International Nuclear Information System (INIS)

Vandergraaf, Tjalle T.; Mamedov, Gudrat G.; Ramazanov, Mahammadali A.; Naghiyev, Jalal A.; Huseynov, Nazim A.; Mehdiyeva, Afat A.

2012-01-01

Much of Azerbaijan's Absheron Peninsula is contaminated by natural U-series and Th-series radionuclides, released in the production of oil and gas and, to a lesser extent, by anthropogenic radionuclides, including Sr-90 and Cs-137, from local industrial activities and trans-border transport. The region contains a large number of pipelines and artificial lagoons that have been used to retain excess groundwater and oil residues. In spite of the long history of the oil and gas industry, radioecological investigations have not been carried out until recently. The purpose of this project is to determine the extent of radionuclide contamination in the Absheron Peninsula using a combination of radiation field measurements and laboratory analyses of selected samples, focusing on ten routes in the vicinity of Baku. The routes were selected as most likely to have become contaminated over time. Soil samples, taken from surface and to a depth of 1 m, aqueous samples from surface waters and marshes, and aqueous and sediment lagoons that showed elevated dosimetry readings, were prepared for gamma spectrometric analysis. Control samples were taken from non-contaminated areas. Samples of air and surface waters were analyzed for Rn-220 and Rn-222. The data will then be used to assess the potential impact of the contamination on the local population. A total slightly 4000 dosimetric readings were taken during the course of this investigation. Of these, 1366 (34%) exceeded 5.4 μR/h. This level is two standard deviations above the mean of the least contaminated route, the 79-km Baku-Guba route. Along the routes Baku-Shemakha and Baku-Guba where no oil and gas activity had taken place, radiation levels of 5.1 ± 1.5 and 4.2 ± 0.6 μR/h, respectively, were obtained. The readings for the route Baku-Guba were then used as representing negligible contamination to which the readings of the other sites were compared. In contrast, along the routes Baku-Lokbatan and Baku-Surakhani, that have

Biogeochemical cycles of Chernobyl-born radionuclides in the contaminated forest ecosystems: long-term dynamics of the migration processes

Science.gov (United States)

Shcheglov, Alexey; Tsvetnova, Ol'ga; Klyashtorin, Alexey

2013-04-01

Biogeochemical migration is a dominant factor of the radionuclide transport through the biosphere. In the early XX century, V.I. Vernadskii, a Russian scientist known, noted about a special role living things play in transport and accumulation of natural radionuclide in various environments. The role of biogeochemical processes in migration and redistribution of technogenic radionuclides is not less important. In Russia, V. M. Klechkovskii and N.V. Timofeev-Ressovskii showed some important biogeochemical aspects of radionuclide migration by the example of global fallout and Kyshtym accident. Their followers, R.M. Alexakhin, M.A. Naryshkin, N.V. Kulikov, F.A. Tikhomirov, E.B. Tyuryukanova, and others also contributed a lot to biogeochemistry of radionuclides. In the post-Chernobyl period, this area of knowledge received a lot of data that allowed building the radioactive element balance and flux estimation in various biogeochemical cycles [Shcheglov et al., 1999]. Regrettably, many of recent radioecological studies are only focused on specific radionuclide fluxes or pursue some applied tasks, missing the holistic approach. Most of the studies consider biogeochemical fluxes of radioactive isotopes in terms of either dose estimation or radionuclide migration rates in various food chains. However, to get a comprehensive picture and develop a reliable forecast of environmental, ecological, and social consequences of radioactive pollution in a vast contaminated area, it is necessary to investigate all the radionuclide fluxes associated with the biogeochemical cycles in affected ecosystems. We believe such an integrated approach would be useful to study long-term environmental consequences of the Fukushima accident as well. In our long-term research, we tried to characterize the flux dynamics of the Chernobyl-born radionuclides in the contaminated forest ecosystems and landscapes as a part of the integrated biogeochemical process. Our field studies were started in June of

Effects of radionuclide contamination on leaf litter decomposition in the Chernobyl exclusion zone

OpenAIRE

Bonzom , Jean-Marc; Hättenschwiler , Stephan; Lecomte-Pradines , Catherine; Chauvet , Eric; Gaschak , Sergey; Beaugelin-Seiller , Karine; Della-Vedova , Claire; Dubourg , Nicolas; Maksimenko , Andrey; Garnier-Laplace , Jacqueline; Adam-Guillermin , Christelle

2016-01-01

International audience; The effects of radioactive contamination on ecosystem processes such as litter decomposition remain largely un- known. Because radionuclides accumulated in soil and plant biomass can be harmful for organisms, the function- ing of ecosystems may be altered by radioactive contamination. Here, we tested the hypothesis that decomposition is impaired by increasing levels of radioactivity in the environment by exposing uncontaminated leaf litter from silver birch and black a...

A method for determining allowable residual contamination levels of radionuclide mixtures in soil

International Nuclear Information System (INIS)

Napier, B.A.

1982-05-01

An important consideration in the disposal of radioactive wastes, and consequently in the preparation of plans for remedial actions at contaminated sites, is the amount of radioactive contamination that may be allowed to remain at any particular waste site. The allowable residual contamination level (ARCL) is dependent on the radiation dose limit imposed, the physical and environmental characteristics of the waste site, and the time at which exposure to the wastes is assumed to occur. The steps in generating an ARCL are generally as follows: (1) develop plausible, credible site-specific exposure scenario; (2) calculate maximum annual radiation doses to an individual for each radionuclide based on the existing physical characteristics of the waste site and the site-specific exposure scenario; (3) calculate the ARCL for the dose limit desired, including all radionuclides present, uncorrected for site cleanup or barrier considerations; and (4) apply any corrections for proposed cleanup activity or addition of barriers to waste migration or uptake to obtain the ARCL applicable to the proposed action. Use of this method allows appropriate application of resources to achieve uniform compliance with a single regulatory standard, i.e., a radiation dose rate limit. Application and modification of the ARCL method requires appropriate models of the environmental transport and fate of radionuclides. Example calculations are given for several specific waste forms and waste site types in order to demonstrate the technique and generate comparisons with other approaches

Semipalatinsk test site: Parameters of radionuclide transfer to livestock and poultry products under actual radioactive contamination

Energy Technology Data Exchange (ETDEWEB)

Baigazinov, Z.; Lukashenko, S. [Institute of Radiation Safety and Ecology (Kazakhstan)

2014-07-01

The IAEA document 'Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Terrestrial and Freshwater Environments' published in 2010 is one of the major sources of knowledge about the migration parameters of radionuclides in the agro-ecosystems that is necessary to assess the dose loads to the population. It is known from there that Sr and Cs transfer has been studied thoroughly, however the factors vary over a wide range. Few studies were conducted for Pu and Am transfer. It should be noted that the studies carried out in real conditions of radioactive contamination, i.e. under natural conditions is also very few. In this regard, since 2007 the territory of the former Semipalatinsk Test Site has been used for comprehensive radioecological studies, where the major radionuclides to be investigated are {sup 90}Sr, {sup 137}Cs, {sup 239+240}Pu, {sup 241}Am. The objects for these studies are birds and animals typical for the region, as well as products obtained from them (lamb, beef, horse meat, chicken, pork, cow's milk, mare's milk, eggs, chicken, chicken feathers, wool, leather). It should be noted that these products are the main agricultural goods that are available in these areas. The studies have been conducted with grazing animals in the most contaminated areas of the test site. Some groups of animals and birds were fed to contaminated feed, soil, contaminated water. Radionuclide intake by animal body with air were studied. Husbandry periods for animals and birds ranged from 1 to 150 days. The transfer parameters to cow and mare's milk have been investigated at single and prolonged intake of radionuclides, also their excretion dynamics has been studied. The studies revealed features of the radionuclide transfer into organs and tissues of animals and birds intaken with hay, water and soil. The results showed that the transfer factors vary up to one order. A relationship has been identified between distribution of

Decontamination of spent ion-exchangers contaminated with cesium radionuclides using resorcinol-formaldehyde resins.

Science.gov (United States)

Palamarchuk, Marina; Egorin, Andrey; Tokar, Eduard; Tutov, Mikhail; Marinin, Dmitry; Avramenko, Valentin

2017-01-05

The origin of the emergence of radioactive contamination not removable in the process of acid-base regeneration of ion-exchange resins used in treatment of technological media and liquid radioactive waste streams has been determined. It has been shown that a majority of cesium radionuclides not removable by regeneration are bound to inorganic deposits on the surface and inside the ion-exchange resin beads. The nature of the above inorganic inclusions has been investigated by means of the methods of electron microscopy, IR spectrometry and X-ray diffraction. The method of decontamination of spent ion-exchange resins and zeolites contaminated with cesium radionuclides employing selective resorcinol-formaldehyde resins has been suggested. Good prospects of such an approach in deep decontamination of spent ion exchangers have been demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

MOIRA models and methodologies for assessing the effectiveness of countermeasures in complex aquatic systems contaminated by radionuclides

Energy Technology Data Exchange (ETDEWEB)

Monte, L. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente; Brittain, J.E. [Oslo Univ., Oslo (Norway); Zoological Museum, Oslo (Norway); Haakanson, L. [Uppsala Univ., Uppsala (Sweden). Inst. of Earth Science; Gallego Diaz, E. [Madrid Univ. Politecnica, Madrid (Spain). Dept. de Ingenieria Nuclear

1999-07-01

The present report is composed of a set of articles written by the partners of the MOIRA project (a model-based computerized system for management support to identify optimal remedial strategies for restoring radionuclide contaminated aquatic ecosystems and drainage areas). The report describes models for predicting the behaviour of radionuclides in complex aquatic systems and the effects of countermeasures for their restoration. [Italian] Il rapporto contiene articoli preparati nell'ambito del progetto MOIRA (a model-based computerized system for management support to identify optimal remedial strategies for restoring radionuclide contaminated aquatic ecosystems and drainage areas), che descrive alcuni modelli per la previsione del comportamento di radionuclidi in sistemi acquatici complessi e per la valutazione dell'effetto delle contromisure per il loro recupero.

MOIRA models and methodologies for assessing the effectiveness of countermeasures in complex aquatic systems contaminated by radionuclides

Energy Technology Data Exchange (ETDEWEB)

Monte, L [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente; Brittain, J E [Oslo Univ., Oslo (Norway); Zoological Museum, Oslo [Norway; Haakanson, L [Uppsala Univ., Uppsala (Sweden). Inst. of Earth Science; Gallego Diaz, E [Madrid Univ. Politecnica, Madrid (Spain). Dept. de Ingenieria Nuclear

1999-07-01

The present report is composed of a set of articles written by the partners of the MOIRA project (a model-based computerized system for management support to identify optimal remedial strategies for restoring radionuclide contaminated aquatic ecosystems and drainage areas). The report describes models for predicting the behaviour of radionuclides in complex aquatic systems and the effects of countermeasures for their restoration. [Italian] Il rapporto contiene articoli preparati nell'ambito del progetto MOIRA (a model-based computerized system for management support to identify optimal remedial strategies for restoring radionuclide contaminated aquatic ecosystems and drainage areas), che descrive alcuni modelli per la previsione del comportamento di radionuclidi in sistemi acquatici complessi e per la valutazione dell'effetto delle contromisure per il loro recupero.

Human dose pathways of radionuclides in forests; Forests ecosystems

Energy Technology Data Exchange (ETDEWEB)

Rantavaara, A. (Radiation and Nuclear Safety Authority, Research and Environmental Surveillance, Helsinki (Finland))

2009-06-15

Forest soil, understorey vegetation and trees are all sources of radionuclides and human radiation doses after contaminating atmospheric deposition. People are exposed to radiation externally from sources outside the body and internally via ingestion and inhalation of radionuclides. Understorey vegetation contributes to ingestion doses through berries, herbs, wild honey, mushrooms and game meat; also trees provide feed to terrestrial birds and big game. During stay in forests people are subject to external radiation from forest floor and overstorey, and they may inhale airborne radioactive aerosol or gaseous radionuclides in ground level air. In the early phase of contamination also resuspended radionuclides may add to the internal dose of people via inhalation. People in Nordic countries are most exposed to radiation via ingestion of radionuclides in wild foods. The distribution of radionuclides in forests is changed by environmental processes, and thereby also the significance of various dose pathways to humans will change with time. External exposure is received in living environment from contaminated stemwood used as building timber and for manufacturing of furniture and other wood products. The aim of this paper is to outline the significance of various human dose pathways of radionuclides in forests considering the public and workers in forestry and production of bioenergy. Examples on effective doses are given based on two historical events, atmospheric nuclear weapon tests (mostly in 1950's and in 1960's) and the Chernobyl nuclear power plant accident in 1986. (au)

Internal exposure of populations to long-lived radionuclides released into the environment

International Nuclear Information System (INIS)

Balonov, M.I.

1997-01-01

This chapter discusses the events that led to the contamination of environments with the long-lived radionuclides of caesium, strontium and other elements, and to the internal exposure of populations living in contaminated areas. Among these events are radioactive releases into the river Techa from the Soviet nuclear weapons facility Mayak in 1949-1956, thermonuclear weapons test in the 1950s and 1960s, the Kyshtim and Windscale accidents in 1957, and the Chernobyl and Tomsk-7 accidents in 1986 and 1993, respectively. Methods of environmental monitoring and individual internal dose monitoring of inhabitants are described. These are based on measuring the content of radionuclides not only in the air, drinking water and local food products, but also in humans using whole-body counters and analysing excreta and autopsy samples. The dynamics of internal exposure of people of different ages to radionuclides of caesium, strontium and plutonium from the environment are considered. Examples of radionuclide distributions in the environment, and of individual/collective internal doses and related medical effects are presented. (Author)

Optimization of monitoring sewage with radionuclide contaminants. Optimizatsiya kontroya stochnykh vod, zagryaznennykh radionuklidami

Energy Technology Data Exchange (ETDEWEB)

Egorov, V N [Vsesoyuznyj Nauchno-Issledovatel' skij Inst. Neorganicheskikh Materialov, Moscow (Russian Federation)

1991-03-01

Recommendations on optimization of monitoring contaminated sewage aimed at enviromental protection agxinst radioactive contamination at minimum cost are presented. The way of selecting water sampling technique depends on water composition stability and flow rate. Depending on the type of radionuclide distribution in the sewage one can estimate minimum frequency of sampling or number of samples sufficient for assuring reliability of the conclusion on the excess or non-excess of permissible radioactive contamination levels, as well as analysis assigned accuracy. By irregular contaminated sewage-discharge and possibility of short-term releases of different form and duration, sampling should be accomplished through automatic devices of continuons or periodic operation.

Sediment and radionuclide transport in rivers: radionuclide transport modeling for Cattaraugus and Buttermilk Creeks, New York

International Nuclear Information System (INIS)

Onishi, Y.; Yabusaki, S.B.; Kincaid, C.T.; Skaggs, R.L.; Walters, W.H.

1982-12-01

SERATRA, a transient, two-dimensional (laterally-averaged) computer model of sediment-contaminant transport in rivers, satisfactorily resolved the distribution of sediment and radionuclide concentrations in the Cattaraugus Creek stream system in New York. By modeling the physical processes of advection, diffusion, erosion, deposition, and bed armoring, SERATRA routed three sediment size fractions, including cohesive soils, to simulate three dynamic flow events. In conjunction with the sediment transport, SERATRA computed radionuclide levels in dissolved, suspended sediment, and bed sediment forms for four radionuclides ( 137 Cs, 90 Sr, 239 240 Pu, and 3 H). By accounting for time-dependent sediment-radionuclide interaction in the water column and bed, SERATA is a physically explicit model of radionuclide fate and migration. Sediment and radionuclide concentrations calculated by SERATA in the Cattaraugus Creek stream system are in reasonable agreement with measured values. SERATRA is in the field performance phase of an extensive testing program designed to establish the utility of the model as a site assessment tool. The model handles not only radionuclides but other contaminants such as pesticides, heavy metals and other toxic chemicals. Now that the model has been applied to four field sites, including the latest study of the Cattaraugus Creek stream system, it is recommended that a final model be validated through comparison of predicted results with field data from a carefully controlled tracer test at a field site. It is also recommended that a detailed laboratory flume be tested to study cohesive sediment transport, deposition, and erosion characteristics. The lack of current understanding of these characteristics is one of the weakest areas hindering the accurate assessment of the migration of radionuclides sorbed by fine sediments of silt and clay

Evaluation and communication of potential risk of radionuclide contamination of foods after Fukushima nuclear power plant accident

International Nuclear Information System (INIS)

Sekizawa, Jun; Nakamura, Yumiko

2011-01-01

A large scale nuclear power plant accident happened after the great earthquake with a huge tsunami in the Eastern part of Japan in March 2011. Potential risk from radionuclide contamination in foods after the nuclear power plant accident was estimated using data of radiological food contamination from the Ministry of Health, Labour and Welfare. Data analyzed by combining nuclide, food, level of radiation detection, period, age-classified population, were compared to provisional index levels of radionuclides, and existing contamination levels in food by natural radioactive potassium. Health risk was shown to be very low or negligible considering presence of background radiological exposure from foods and the environment. Appropriate explanation of risk to various stakeholders of the society is imperative and results of trials were reported. (author)

REIDAC. A software package for retrospective dose assessment in internal contamination with radionuclides

International Nuclear Information System (INIS)

Kurihara, Osamu; Kanai, Katsuta; Takada, Chie; Takasaki, Koji; Ito, Kimio; Momose, Takumaro; Hato, Shinji; Ikeda, Hiroshi; Oeda, Mikihiro; Kurosawa, Naohiro; Fukutsu, Kumiko; Yamada, Yuji; Akashi, Makoto

2007-01-01

For cases of internal contamination with radionuclides, it is necessary to perform an internal dose assessment to facilitate radiation protection. For this purpose, the ICRP has supplied the dose coefficients and the retention and excretion rates for various radionuclides. However, these dosimetric quantities are calculated under typical conditions and are not necessarily detailed enough for dose assessment situations in which specific information on the incident or/and individual biokinetic characteristics could or should be taken into account retrospectively. This paper describes a newly developed PC-based software package called Retrospective Internal Dose Assessment Code (REIDAC) that meets the needs of retrospective dose assessment. REIDAC is made up of a series of calculation programs and a package of software. The former calculates the dosimetric quantities for any radionuclide being assessed and the latter provides a user with the graphical user interface (GUI) for executing the programs, editing parameter values and displaying results. The accuracy of REIDAC was verified by comparisons with dosimetric quantities given in the ICRP publications. This paper presents the basic structure of REIDAC and its calculation methods. Sensitivity analysis of the aerosol size for 239 Pu compounds and provisional calculations for wound contamination with 241 Am were performed as examples of the practical application of REIDAC. (author)

Artificial radionuclides in soil, flora and fauna

International Nuclear Information System (INIS)

Marej, A.N.

1984-01-01

Sources and ways of soil contamination by radionuclides, as well as the main regularities of radionuclide behaviour in soils, are discussed. Ways of radionuclide uptake by plants are discussed in detail, since radionuclide contamination of vegetation, and agricultural plants and pastures in particular, is one of the main factors, determining sanitary value of environmental contamination by radioactive substances

The transfer of radionuclides from contaminated groundwater into perennial ryegrass and winter wheat

International Nuclear Information System (INIS)

Wadey, P.; Shaw, G.; Butler, A. P.; Tompkins, J. A.; Wheater, H. S.

1996-01-01

Lysimeter studies of the migration of radionuclides from a contaminated water table and their subsequent uptake by plant roots have been undertaken using two distinct soil types and varying crop regimes. An eight year multi-disciplinary research project (funded by Nirex) has concentrated on the upward migration of contaminants from near-surface water tables, and their uptake by winter wheat and perennial ryegrass crops. Experimental data are presented for the movement and uptake of radiocaesium 137 Cs. These data show significant movement in the unsaturated zone during the first year of dosing, followed by progressively reduced availability in subsequent years. A suite of physically based hydrological and solute transport models has been developed to model radionuclide transport in the unsaturated zone. Model simulations, based on a conventional advection-dispersion representation incorporating linear sorption processes, were unable to describe adequately the distribution of radiocaesium within the soil profile. However, the introduction of root storage and translocation processes provided significantly improved results. (author)

Radionuclide contaminated micromycetes in the soil the thirty kilometer zone

International Nuclear Information System (INIS)

Zhdanova, N.N.; Vasilevskaya, A.I.; Redchits, T.I.; Gavrilov, V.I.; Lashko, T.N.; Luchkov, P.N.; Shcherbachenko, A.M.; AN Ukrainskoj SSR, Kiev

1992-01-01

From 1986 year the ecological monitoring of the soil microscopic fungi exist under conditions of the radioactive contamination in the thirty kilometer zone of the Chernobyl' NPP is conducted. As mycological isotope soil analysis the limiting factor in the ecological situation need consider the radionuclide contamination of the soils. It is shown, that the amount of fungus germs decreased by 200 times in 1986 year and increased sharp to 1989-90 years. During the first years after the accident, in the most contaminated soils dark-pigmented fungi predominated. It is due to a deep reorganization of the soil micromycete associations. Correlations is revealed in the interrelations among various species of fungi, isolated from the soils, differed in the radioactivity. Among 12 species of fungi (from 6 genuses of micromycetes) isotope accumulation is noted. There are Sr-90 and Cs-137, most widespread in the soil after the accident. 18 refs.; 8 figs

Derived intervention levels for radionuclides in food

International Nuclear Information System (INIS)

1988-01-01

After the nuclear accident at Chernobyl in 1986, many countries were affected by widespread radioactive contamination. It became clear that the available guidance on dealing with the consequences of a nuclear accident was inappropriate for the long term and for areas far removed from the accident site. A particular concern was the safety of radioactively contaminated food and drinking-water in the ''far field'' region. The present guidelines, based on health protection principles, have been prepared by the World Health Organization in response to this concern. For various food categories, recommendations are made on levels of contamination by radionuclides at which corrective action might be justified to reduce the health risk to the population. The guidelines are based on accepted radiation dose criteria, on food consumption data from different parts of the world, and on dosimetric information for the relevant radionuclides. They are intended to assist in national decision-making in the event of another major nuclear accident. Refs, 1 fig., 14 tabs

Marine sediments as a sink, and contaminated sediments as a diffuse source of radionuclides

International Nuclear Information System (INIS)

Salbu, B.; Borretzen, P.

1997-01-01

Full text: Marine sediments may act as a sink for radionuclides originating from atmospheric fallout (e.g. Chernobyl accident), for radionuclides in discharges from nuclear installations (e.g. Sellafield, UK) for river transported radionuclides, and radionuclides released from nuclear waste dumped at sea (e.g. fjords at Novaya Zemlya). In order to assess short and long term consequences of radionuclides entering the marine ecosystem, the role of sediments as a relatively permanent sink and the potential for contaminated sediments to act as a diffuse source should be focused. The retention of radionuclides in sediments will depend on the source term, i.e. the physico-chemical forms of radionuclides entering the system and on interactions with various sediment components. Radionuclides associated with particles or aggregating polymers are removed from the water phase by sedimentation, while sorption to surface sediment layers is of relevance for ionic radionuclide species including negatively charged colloids. With time, transformation processes will influence the mobility of radionuclides in sediments. The diffusion into mineral lattices will increase fixation, while the influence of for instance red/ox conditions and bio-erosion may mobilize radionuclides originally fixed in radioactive particles. Thus, information of radionuclides species, surface interactions, transformation processes and kinetics is essential for reducing the uncertainties in marine transfer models. Dynamic model experiments where chemically well defined tracers are added to a sea water-marine sediment system are useful for providing information on time dependent interactions and distribution coefficients. When combined with sequential extraction techniques, information on mobility and rate of fixation is subsequently attained. In the present work experimental results from the Irish Sea and the Kara Sea will be discussed

Bioaccumulation of radionuclides and metals by microorganisms: Potential role in the separation of inorganic contaminants and for the in situ treatment of the subsurface

International Nuclear Information System (INIS)

Bolton, H. Jr.; Wildung, R.E.

1993-01-01

Radionuclide, metal and organic contaminants are present in relatively inaccessible subsurface environments at many U.S Department of Energy (DOE) sites. Subsurface contamination is of concern to DOE because the migration of these contaminants into relatively deep subsurface zones indicates that they exist in a mobile chemical form and thus could potentially enter domestic groundwater supplies. Currently, economic approaches to stabilize or remediate these deep contaminated zones are limited, because these systems are not well characterized and there is a lack of understanding of how geochemical, microbial, and hydrological processes interact to influence contaminant behavior. Microorganisms offer a potential means for radionuclide and metal immobilization or mobilization for subsequent surface treatment. Bioaccumulation is a specific microbial sequestering mechanism wherein mobile radionuclides and metals become associated with the microbial biomass by both intra- and extracellular sequestering ligands. Since most of the microorganism in the subsurface are associated with the stationary strata, bioaccumulation of mobile radionuclides and metals would initially result in a decrease in the transport of inorganic contaminants. How long the inorganic contaminants would remain immobilized, the selectivity of the bioaccumulation process for specific inorganic contaminants, the mechanism involved, and how the geochemistry and growth conditions of the subsurface environment influence bioaccumulation are not currently known. This presentation focuses on the microbial process of immobilizing radionuclides and metals and using this process to reduce inorganic contaminant migration at DOE sites. Background research with near-surface microorganisms will be presented to demonstrate this process and show its potential to reduce inorganic contaminant migration. Future research needs and approaches in this relatively new research area will also be discussed

Microbe and Mineral Mediated Transformation of Heavy Metals, Radionuclides, and Organic Contaminants

Science.gov (United States)

Gerlach, R.

2011-12-01

Microorganisms influence their surroundings in many ways and humans have utilized microbially catalyzed reactions for benefit for centuries. Over the past few decades, microorganisms have been used for the control of contaminant transport in subsurface environments where many microbe mineral interactions occur. This presentation will discuss microbially influenced mineral formation and transformation as well as their influence on the fate of organic contaminants such as chlorinated aliphatics & 2,4,6-trinitrotoluene (TNT), heavy metals such as chromium, and radionuclides such as uranium & strontium. Both, batch and flow experiments have been performed, which monitor the net effect of microbe mineral interactions on the fate of these contaminants. This invited presentation will place an emphasis on the relative importance of direct microbial (i.e. biotic) transformations, mineral-mediated transformations as well as other abiotic reactions influencing the fate of environmental contaminants. Experiments will be summarized and placed in context of past and future engineered applications for the control of subsurface contaminants.

Risk governance on radionuclide contamination in food in Japan

International Nuclear Information System (INIS)

Sekizawa, Jun

2012-01-01

A large scale nuclear power plant accident happened after the great earthquake in Fukushima in March 2011. There was several critical mismanagement of the accident which resulted in the radio-nuclides release in the environment. Furthermore the information delay and the lack in delivery of clear and comprehensible explanation of the risk have been causing huge anxieties and worries among people living near to the site, and also people in the nation. Risk assessment appeared not to meet appropriately requests of risk management authorities and also people. Author has been trying to straighten the large amounts of data on radionuclide contamination in foods so as for people to easily understand the real situation with succinct messages explaining risk and to take appropriate actions in facing the risk. Appropriate responses and coordination among the risk managing authorities are indispensable especially in this kind of huge accident which may entail vast scale and long lasting risk and a new paradigm of the food safety governance is required in Japan. (author)

Radionuclide activity and the immune system functioning in residents of radiation contaminated areas

Directory of Open Access Journals (Sweden)

V. L. Sokolenko

2015-09-01

Full Text Available The objective of this research is to assess the relation of radioactive contamination degree to immune system functioning, in the absence or presence of additional potential immunosuppressants. To achieve the objective, during the period of 1995–2015 we examined 250 people, students of Cherkasy State University, who lived in the areas of enhanced radiation monitoring before. Also we evaluated the additional impact of the emotional stress caused by examinations on examined students. Indicators of cellular immunity were determined by immunophenotyping and dyeing using Romanowsky-Giemsa method. The level of immunoglobulins in blood serum was determined by radial immunodiffusion (Mancini method. The level of cortisol in blood serum was determined by immunoenzyme method. We have found that in absence of the emotional stress among residents of the areas contaminated with radionuclides, cortisol level remained at the upper limit of homeostatic norm. There is an average positive correlation between the activity of radionuclides in the territories of residence and the level of cortisol. There are marked average positive correlations between the activity of radionuclides and the level of neutrophils, and low positive correlations with the levels of IgG and IgM in blood serum. Average negative correlations between the activity of radionuclides and the following parameters are also observed: absolute and relative number of functionally mature T-lymphocytes with phenotype CD3+, absolute and relative number of their helper subpopulation CD4+, absolute and relative number of natural killer cells with phenotype CD16+; and strong negative correlations with immunoregulatory index CD4+/CD8+. Cortisol level shows the similar correlation with the same parameters, but correlation coefficient is lower. Under conditions of additional stress, caused by emotional load during the examinations, cortisol level significantly increases. This enhanced previously discovered

[Radionuclides in siberian Thymallus from radiation-contaminated area in the middle stream of the Yenisei River].

Science.gov (United States)

Zotina, T A; Trofimova, E A; Bolsunovskiĭ, A Ia

2012-01-01

Concentration of artificial radionuclides in bodies of arctic grayling from the radioactively contaminated zone of the Yenisei River in the vicinity of the Mining-and-Chemical Combine of Rosatom was investigated in 2007-2010. Gamma-spectrometric analysis revealed artificial radionuclides in all the organs and tissues of fish. The isotope composition was the most diverse (60Co, 65Zn, 85Sr, 99Mo, 106Ru, 137Cs, 144Ce) in internal organs of grayling. The activity of radionuclides increased in internal organs including liver and kidney and in the content of digestive tract of grayling during winter and spring, which coincided with the change in the feeding spectrum of grayling. The trophic transfer factor of radionuclides from zoobenthos (Philolimnogammarus spp.) to whole bodies and muscles of grayling was over 1 (1.8-2.4) only for natural radionuclide 40K. The trophic transfer of artificial radionuclides (60Co, 65Zn, 137Cs) to muscles and bodies of grayling was one-two orders of magnitude less effective.

MOIRA models and methodologies for assessing the effectiveness of countermeasures in complex aquatic systems contaminated by radionuclides

International Nuclear Information System (INIS)

Monte, L.; Haakanson, L.; Gallego Diaz, E.

1999-01-01

The present report is composed of a set of articles written by the partners of the MOIRA project (a model-based computerized system for management support to identify optimal remedial strategies for restoring radionuclide contaminated aquatic ecosystems and drainage areas). The report describes models for predicting the behaviour of radionuclides in complex aquatic systems and the effects of countermeasures for their restoration [it

Effects of radionuclide contamination on leaf litter decomposition in the Chernobyl exclusion zone.

Science.gov (United States)

Bonzom, Jean-Marc; Hättenschwiler, Stephan; Lecomte-Pradines, Catherine; Chauvet, Eric; Gaschak, Sergey; Beaugelin-Seiller, Karine; Della-Vedova, Claire; Dubourg, Nicolas; Maksimenko, Andrey; Garnier-Laplace, Jacqueline; Adam-Guillermin, Christelle

2016-08-15

The effects of radioactive contamination on ecosystem processes such as litter decomposition remain largely unknown. Because radionuclides accumulated in soil and plant biomass can be harmful for organisms, the functioning of ecosystems may be altered by radioactive contamination. Here, we tested the hypothesis that decomposition is impaired by increasing levels of radioactivity in the environment by exposing uncontaminated leaf litter from silver birch and black alder at (i) eleven distant forest sites differing in ambient radiation levels (0.22-15μGyh(-1)) and (ii) along a short distance gradient of radioactive contamination (1.2-29μGyh(-1)) within a single forest in the Chernobyl exclusion zone. In addition to measuring ambient external dose rates, we estimated the average total dose rates (ATDRs) absorbed by decomposers for an accurate estimate of dose-induced ecological consequences of radioactive pollution. Taking into account potential confounding factors (soil pH, moisture, texture, and organic carbon content), the results from the eleven distant forest sites, and from the single forest, showed increased litter mass loss with increasing ATDRs from 0.3 to 150μGyh(-1). This unexpected result may be due to (i) overcompensation of decomposer organisms exposed to radionuclides leading to a higher decomposer abundance (hormetic effect), and/or (ii) from preferred feeding by decomposers on the uncontaminated leaf litter used for our experiment compared to locally produced, contaminated leaf litter. Our data indicate that radio-contamination of forest ecosystems over more than two decades does not necessarily have detrimental effects on organic matter decay. However, further studies are needed to unravel the underlying mechanisms of the results reported here, in order to draw firmer conclusions on how radio-contamination affects decomposition and associated ecosystem processes. Copyright © 2016 Elsevier B.V. All rights reserved.

Classification and Reevaluation on Radionuclide and Activity of Contaminated Soil(I)

Energy Technology Data Exchange (ETDEWEB)

Kang, Il Sik; Shon, J. S.; Kim, K. J.; Kim, T. K.; Hong, D. S.; Lee, B. C.; Cho, H. S.; Je, W. G

2006-03-15

Radioactive wastes generated during the decommissioning process and contaminated soils were transported and have been stored at the waste storage facility. The radioactivity in the wastes has been decayed a lot. The radionuclide and the activity concentration of stored soil wastes were reevaluated. And using the reevaluation results, the soil wastes were classified as either a regulatory clearance wastes or a radioactive waste. The storage space can be secured by storing regulatory clearance wastes in the extra storage facility and self disposing them. Also, the objective is to protect the environment from contamination by observing the related nuclear regulation and managing the radioactive wastes. Through the reevaluation of radioactivity and classification of contaminated soils, the unnecessary decontamination of uncontaminated soil was prevented. It allowed us to save the cost for decontamination and disposal, also we could secure the pretreatment process techniques such as how to sample and analyze the nuclide.

ASSESSMENTOF BETA PARTICLE FLUX FROM SURFACE CONTAMINATION AS A RELATIVE INDICATOR FOR RADIONUCLIDE DISTRIBUTION ON EXTERNAL SURFACES OF A MULTI-STORY BUILDING IN PRIPYAT

Energy Technology Data Exchange (ETDEWEB)

Farfan, E.

2009-11-17

How would we recover if a Radiological Dispersion Device (e.g., dirty bomb) or Improvised Nuclear Device were to detonate in a large city? In order to assess the feasibility of remediation following such an event, several issues would have to be considered, including the levels and characteristics of the radioactive contamination, the availability of the required resources to accomplish decontamination, and the planned future use of the city's structures and buildings. Presently little is known about the distribution, redistribution, and migration of radionuclides in an urban environment. However, Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident, may provide some answers. The main objective of this study was to determine the radionuclide distribution on a Pripyat multi-story building, which had not been previously decontaminated and therefore could reflect the initial fallout and its further natural redistribution on external surfaces. The 7-story building selected was surveyed from the ground floor to the roof on horizontal and vertical surfaces along seven ground-to-roof transections. Some of the results from this study indicate that the upper floors of the building had higher contamination levels than the lower floors. The authors consequently recommend that existing decontamination procedures for tall structures be re-examined and modified accordingly.

Potato production on private plots contaminated by radionuclides

International Nuclear Information System (INIS)

Bogdevitch, I.; Tarasiuk, S.

2004-01-01

Potatoes is one of the basis food products of man diet, especially in country area. Recent research has shown that 137 Cs content in potato tubers does not exceed the permissible level at the potato growing on radioactive contaminated land in Belarus. However up to 240-300 kg of potatoes is consumed per man during year and potato yield determines significant share of the internal dose of radiation. Moreover, extra potato yield sold on market is forming the essential part of the rural family budget. Therefore the reducing of 137 Cs content in potatoes and increasing of potato yield could be allowed to improve of quality life of rural inhabitants on contaminated areas. The application of protection measures on private plots are restricted by lack of the knowledge and financial deficit. The involvement of rural inhabitants in processes of self-rehabilitation and self-development could be a way to improve the quality life on radioactive contaminated territory There is strong motivation for inhabitants to increase the yield and to reduce the radionuclide concentration in potatoes. How to develop the conditions for the sustainable potato production by private producers on affected land? There are several factors to consider. Firstly, the rural inhabitants should be actively involved as initiators to improve their quality life. Secondly, the potato technology should be adopted to the local territory and tested by producers on radiological and economic efficiency. Thirdly, the common village initiatives should be developed for supplying by new varieties of seeds and fertilizers, selling of yield, consulting, crediting etc. The step-by-step solution of described strategy could allow improving and stabilizing the potato production by rural community. The training of rural people as an initial step was realized to transfer to the inhabitants the practical skills that can be used in their day-to-day life within framework of 'ETHOS-II' project. The experimental potato

Metabolism of radionuclides in domestic animals

International Nuclear Information System (INIS)

Wirth, E.; Leising, C.

1986-01-01

The reactor accident at Chernobyl has shown that shortly after the contamination of the environment radionuclides can be found in animal products. The main contamination pathways of domestic animas are: uptake of radionuclides by foodstuffs; uptake of radionuclides by contaminated drinking water; uptake of radionuclides by inhalation; uptake of radionuclides through skin; uptake of radionuclides by ingestion of soil particles. Generally the uptake of radionuclides by food is the dominant exposure pathway. In rare cases the inhalation of radionuclides or the uptake by drinking water may be of importance. The metabolism of incorporated radionuclides is comparable to the respective metabolism of essential mass or trace elements or heavy metals. Radioisotopes of essential elements are for instance iron 55, manganese 54, cobalt 58 and cobalt 60. Other elements are typical antagonists to essential elements, e.g. strontium 90 is an antagonist to calcium or cesium 137 to potassium. Lead 210 and plutonium 239 behave similarly as heavy metals. Generally the knowledge of the metabolism of trace and mass elements, of antagonistic and synergistic elements and heavy metals can be applied to these radionuclides

Selective flotation for the removal of radionuclides from contaminated soil

International Nuclear Information System (INIS)

Miller, J.D.; Yu, Q.; Lu, Y.Q.

1995-01-01

Low-level radioactive contaminated soils (10--500 pci/gm) created by defense-related activities at certain Superfund sites, such as Nevada Test Site (NTS), is a current environmental concern. Many of these contaminated sites may require appropriate cleanup and restoration, which could cost billions of dollars and put tremendous pressure on limited financial resources. Therefore, the development of a selective flotation process to separate such radionuclides from contaminated soils should be considered. In this study, both a pure depleted UO 2 sample and three synthetic UO 2 /soil mixtures were used to evaluate surface chemistry features and to examine the possibility for the flotation of fine UO 2 particles from selected soils. It was intended that this model system would be a reasonable representation of contaminated soils such as those found the Nevada Test Site which are reported to be contaminated by PuO 2 fallout. The effect of reagent schedule, particle size distribution, and surface charge are discussed with respect to the flotation separation of the UO 2 /soil mixtures. It was found that both commercial fatty acids and reagent grade sodium oleate are effective collectors for UO 2 flotation provided the pH is adjusted to the range of pH 8--9. The bench-scale flotation results successfully demonstrated that froth flotation technology can be used to remove UO 2 from such model contaminated soils with appropriate flotation chemistry conditions which depend on the soil characteristics and other pretreatment procedures

Evaluation of the absorbed doses in conditions of external and internal contamination with radionuclides

International Nuclear Information System (INIS)

Milivojevic, K.; Stojanovic, D.; Markovic, P.

1981-01-01

In experimental conditions of contamination with radionuclides of the skin and skin injuries, an evaluation of the degree of local irradiation in decontamined region and doses absorbed in organs of selective accumulating was carried out by use of mathematical models and tissue-equivalent thermoluminescent dosemeters. The evaluation of the absorbed doses based on conception, that in adequate analyses of decontamination effect, as a most efficient medico-prophilactic measure from local and total irradiation, should be taken into account the total body burden of the penetrated radionuclide, selective accumulating in critical organs or tissues, as well as the residual radioactivity in decontaminated region. (author)

Estimation of the effect of radionuclide contamination on Vicia sativa L. induction of chlorophyll fluorescence parameters using "Floratest" optical biosensor

Science.gov (United States)

Ruban, Yu.; Illienko, V.; Nesterova, N.; Pareniuk, O.; Shavanova, K.

2017-12-01

The presented research was aimed to determine the parameters of chlorophyll fluorescence (IChH) curve induction for Vicia sativa L. that were grown on radionuclide contaminated soils by using "Floratest" fluorometer. Plants were inoculated with 5 species of bacteria that might potentially block radionuclide uptake (Agrobacterium radiobacter IMBB-7246, Azotobacter chroococcum UKMB-6082, A. chroococcum UKMB-6003, Bacillus megaterium UKMB-5724, Rhizobium leguminosarum bv. viceae) and grown in sod-podzolic, chernozem and peat-bog soils, contaminated with 137Cs (4000±340 Bq/kg). As a result of research, it was determined that the most stressful factors for vetch plants are combination of soil radionuclide and presence of Bacillus megaterium UKM B-5724, as the number of inactive chlorophyll increased. In addition, the vetch plants significantly increased fixed level of fluorescence (Fst) under the influence of radioactive contamination in presence of Bacillus megaterium UKM B-5724, indicating inhibition of photosynthetic reactions. Other bacteria showed radioprotective properties in almost all types of soil.

Techniques for assessing the performance of in situ bioreduction and immobilization of metals and radionuclides in contaminated subsurface environments

Energy Technology Data Exchange (ETDEWEB)

Jardine, P.M.; Watson, D.B.; Blake, D.A.; Beard, L.P.; Brooks, S.C.; Carley, J.M.; Criddle, C.S.; Doll, W.E.; Fields, M.W.; Fendorf, S.E.; Geesey, G.G.; Ginder-Vogel, M.; Hubbard, S.S.; Istok, J.D.; Kelly, S.; Kemner, K.M.; Peacock, A.D.; Spalding, B.P.; White, D.C.; Wolf, A.; Wu, W.; Zhou, J.

2004-11-14

Department of Energy (DOE) facilities within the weapons complex face a daunting challenge of remediating huge below inventories of legacy radioactive and toxic metal waste. More often than not, the scope of the problem is massive, particularly in the high recharge, humid regions east of the Mississippi river, where the off-site migration of contaminants continues to plague soil water, groundwater, and surface water sources. As of 2002, contaminated sites are closing rapidly and many remediation strategies have chosen to leave contaminants in-place. In situ barriers, surface caps, and bioremediation are often the remedial strategies of chose. By choosing to leave contaminants in-place, we must accept the fact that the contaminants will continue to interact with subsurface and surface media. Contaminant interactions with the geosphere are complex and investigating long term changes and interactive processes is imperative to verifying risks. We must be able to understand the consequences of our action or inaction. The focus of this manuscript is to describe recent technical developments for assessing the performance of in situ bioremediation and immobilization of subsurface metals and radionuclides. Research within DOE's NABIR and EMSP programs has been investigating the possibility of using subsurface microorganisms to convert redox sensitive toxic metals and radionuclides (e.g. Cr, U, Tc, Co) into a less soluble, less mobile forms. Much of the research is motivated by the likelihood that subsurface metal-reducing bacteria can be stimulated to effectively alter the redox state of metals and radionuclides so that they are immobilized in situ for long time periods. The approach is difficult, however, since subsurface media and waste constituents are complex with competing electron acceptors and hydrogeological conditions making biostimulation a challenge. Performance assessment of in situ biostimulation strategies is also difficult and typically requires detailed

Allowable residual contamination levels of radionuclides in soil from pathway analysis

International Nuclear Information System (INIS)

Nyquist, J.E.; Baes, C.F. III.

1987-01-01

The uncertainty regarding radionuclide distributions among Remedial Action Program (RAP) sites and long-term decommissioning and closure options for these sites requires a flexible approach capable of handling different levels of contamination, dose limits, and closure scenarios. We identified a commercially available pathway analysis model, DECOM, which had been used previously in support of remedial activities involving contaminated soil at the Savannah River Plant. The DECOM computer code, which estimates concentrations of radionuclides uniformly distributed in soil that correspond to an annual effective dose equivalent, is written in BASIC and runs on an IBM PC or compatible microcomputer. We obtained the latest version of DECOM and modified it to make it more user friendly and applicable to the Oak Ridge National Laboratory (ORNL) RAP. Some modifications involved changes in default parameters or changes in models based on approaches used by the EPA in regulating remedial actions for hazardous substances. We created a version of DECOM as a LOTUS spreadsheet, using the same models as the BASIC version of DECOM. We discuss the specific modeling approaches taken, the regulatory framework that guided our efforts, the strengths and limitations of each approach, and areas for improvement. We also demonstrate how the LOTUS version of DECOM can be applied to specific problems that may be encountered during ORNL RAP activities. 18 refs., 2 figs., 3 tabs

Radionuclides in bats using a contaminated pond on the Nevada National Security Site, USA

International Nuclear Information System (INIS)

Warren, Ronald W.; Hall, Derek B.; Greger, Paul D.

2014-01-01

Perched groundwater percolating through radionuclide contamination in the E Tunnel Complex on the Nevada National Security Site, formerly the Nevada Test Site, emerges and is stored in a series of ponds making it available to wildlife, including bats. Since many bat species using the ponds are considered sensitive or protected/regulated and little information is available on dose to bats from radioactive water sources, bats were sampled to determine if the dose they were receiving exceeded the United States Department of Energy dose limit of 1.0E-3 Gy/day. Radionuclide concentrations in water, sediment, and flying insects were also measured as input parameters to the dose rate model and to examine trophic level relationships. The RESRAD-Biota model was used to calculate dose rates to bats using different screening levels. Efficacy of RESRAD-Biota and suggested improvements are discussed. Dose to bats foraging and drinking at these ponds is well below the dose limit set to protect terrestrial biota populations. - Highlights: • Bats uptake radionuclides from a contaminated pond. • Tritium had highest concentrations but 137 Cs gave highest dose. • Tritium concentrations in bats are approximately one-twentieth of that in the pond. • Population level effects are not expected based on RESRAD-Biota dose estimates. • It may be more appropriate to model the bats as riparian animals in RESRAD-Biota

β-ray track imaging application in phytoremediation of radionuclide-contaminated soil

International Nuclear Information System (INIS)

Wan Junsheng; Xiao Yan; Pan Xiaobing; Tang Xiuhuan; Yang Yongqing; Wang Beisong; Zhao Xiangfeng; Li Hua; Miao Zhengqiang; Yang Jun

2008-01-01

The phytoremediation was widely studied in the field of treating technology of soil contamination with long-lived nuclides. Studies on the β-ray track imaging application in phytoremediation of radionuclide-contaminated soil were carried out in the present work. Experiments showed that this technology might be used for screening plants for phytoremediation and for the studies of phytoremediation mechanism, such as radioactivity concentration and distribution in plant organs. The influence of α- and γ-rays on the β-ray track imaging was studied. Theoretical studies showed that the influence of α-rays might be heavily reduced with proper thickness of PE-film. The image sensor was not so sensitive to γ-rays as β-rays, and the influence of surrounding γ-rays could be heavily reduced with a proper thickness of Pb-shielding

Towards improved understanding of radionuclide transfer in forests and preparedness to handle contaminated forests. Proceedings

International Nuclear Information System (INIS)

Vetikko, V.; Rantavaara, A.; Aro, L.; Plamboeck, A.H.; Straelberg, E.

2009-06-01

The seminar was planned and arranged by four Nordic organisations and provided a forum for exchange of information for Nordic scientists currently working in the field of forest radioecology or using the data. Presentations of research on nutrient cycling and radionuclide distribution in boreal forests, discussion on the needs for future research and attendance of experts on forestry, forest research and radioecology offered a unique opportunity to disseminate and receive information. The seminar programme was composed of topics of radioecology and forest research, assessment of radionuclide contamination and management of contaminated forests. Also sampling in forests, monitoring and modelling of environmental impact of disposal of spent nuclear fuel, and recent radioecological studies on forests were handled. Future research was emphasised in discussions. Below is a short compilation of these discussions: - Comprehensive planning of research projects contributing to a programme with long-term aims is possible in broadly-based multidisciplinary collaboration. Thereby independent initiatives and less coherent plans can be replaced. - Clear definition of hypotheses, planning and improving the specific methods for sampling and laboratory analyses were found crucial. - Effects of intensive biofuel harvesting on the nutrient and radionuclide flows in forests are major issues in the next decades. - Gaps in knowledge, such as lack of data on processes contributing to radionuclide distributions in forests, and on certain long-lived radionuclides (those of Cl, Tc, Np, etc.) contributing to the environmental impact of final disposal of spent nuclear fuel. Topical seminars like the one accomplished are welcome in the future; compiling acute issues of multidisciplinary nature for focussed expert review and discussion can be very rewarding in many ways. To support communication and future collaboration, an informal forest network was launched in the seminar. Information is

Towards improved understanding of radionuclide transfer in forests and preparedness to handle contaminated forests. Proceedings

Energy Technology Data Exchange (ETDEWEB)

Vetikko, V.; Rantavaara, A. (Radiation and Nuclear Safety Authority (STUK) (Finland)); Aro, L. (Finnish Forest Research Institute (METLA) (Finland)); Plamboeck, A.H. (The Swedish Defence Research Agency (FOI) (Sweden)); Straalberg, E. (Institute for Energy Technology (IFE) (Norway))

2009-06-15

The seminar was planned and arranged by four Nordic organisations and provided a forum for exchange of information for Nordic scientists currently working in the field of forest radioecology or using the data. Presentations of research on nutrient cycling and radionuclide distribution in boreal forests, discussion on the needs for future research and attendance of experts on forestry, forest research and radioecology offered a unique opportunity to disseminate and receive information. The seminar programme was composed of topics of radioecology and forest research, assessment of radionuclide contamination and management of contaminated forests. Also sampling in forests, monitoring and modelling of environmental impact of disposal of spent nuclear fuel, and recent radioecological studies on forests were handled. Future research was emphasised in discussions. Below is a short compilation of these discussions: - Comprehensive planning of research projects contributing to a programme with long-term aims is possible in broadly-based multidisciplinary collaboration. Thereby independent initiatives and less coherent plans can be replaced. - Clear definition of hypotheses, planning and improving the specific methods for sampling and laboratory analyses were found crucial. - Effects of intensive biofuel harvesting on the nutrient and radionuclide flows in forests are major issues in the next decades. - Gaps in knowledge, such as lack of data on processes contributing to radionuclide distributions in forests, and on certain long-lived radionuclides (those of Cl, Tc, Np, etc.) contributing to the environmental impact of final disposal of spent nuclear fuel. Topical seminars like the one accomplished are welcome in the future; compiling acute issues of multidisciplinary nature for focussed expert review and discussion can be very rewarding in many ways. To support communication and future collaboration, an informal forest network was launched in the seminar. Information is

Amelioration of soils contaminated with radionuclides: exploiting biodiversity to minimise or maximise soil to plant transfer

Energy Technology Data Exchange (ETDEWEB)

Willey, N. [University of the West of England, Centre for Research in Plant Science, Bristol (United Kingdom)

2004-07-01

Managing the transfer of radionuclides from soils into plants and thence food chains is an important immediate post-accident challenge for radio-ecologists. In the longer term, soil remediation is often necessary to eliminate the environmental impacts of accidents. Until the recent advent of molecular phylogenies for flowering plants there was no scientific framework through which to analyse the contribution of inter-species differences in radionuclide uptake by plants to these processes. We have already carried out such analyses for a variety of heavy metals and here report new biodiversity landscapes across the flowering plant phylum for radionuclides of Cs, Sr, S, Cl, I, Co and Ru that identify groups of plants with particularly low and high uptake. The plant groups are an untapped reservoir of biodiversity that might be exploited for minimising food chain contamination or maximising phyto-extraction of radionuclides. We have recently demonstrated the importance of biodiversity in minimising food chain contamination with {sup 137}Cs and exploiting biodiversity has recently brought spectacular and unexpected advances in phyto-extraction of As. The UK Food Standards Agency food chain model and recent advances in our phyto-extraction field trial at Bradwell Nuclear Power Station, UK will be used to illustrate for the first time the use of biodiversity landscapes for post-accident management and soil remediation. Biodiversity landscapes of inter-species differences in radionuclide uptake are also a foundation for a variety of developments in the genetic engineering of plant uptake and response to radionuclides. Results building on recent work we have carried out using K transport mutants of Arabidopsis and its implications for transport processes and engineering them in flowering plants will be discussed. Further, novel ongoing genomic and proteomic work into the molecular responses of Arabidopsis to ionising radiation and its implications for selecting plants from

Amelioration of soils contaminated with radionuclides: exploiting biodiversity to minimise or maximise soil to plant transfer

International Nuclear Information System (INIS)

Willey, N.

2004-01-01

Managing the transfer of radionuclides from soils into plants and thence food chains is an important immediate post-accident challenge for radio-ecologists. In the longer term, soil remediation is often necessary to eliminate the environmental impacts of accidents. Until the recent advent of molecular phylogenies for flowering plants there was no scientific framework through which to analyse the contribution of inter-species differences in radionuclide uptake by plants to these processes. We have already carried out such analyses for a variety of heavy metals and here report new biodiversity landscapes across the flowering plant phylum for radionuclides of Cs, Sr, S, Cl, I, Co and Ru that identify groups of plants with particularly low and high uptake. The plant groups are an untapped reservoir of biodiversity that might be exploited for minimising food chain contamination or maximising phyto-extraction of radionuclides. We have recently demonstrated the importance of biodiversity in minimising food chain contamination with 137 Cs and exploiting biodiversity has recently brought spectacular and unexpected advances in phyto-extraction of As. The UK Food Standards Agency food chain model and recent advances in our phyto-extraction field trial at Bradwell Nuclear Power Station, UK will be used to illustrate for the first time the use of biodiversity landscapes for post-accident management and soil remediation. Biodiversity landscapes of inter-species differences in radionuclide uptake are also a foundation for a variety of developments in the genetic engineering of plant uptake and response to radionuclides. Results building on recent work we have carried out using K transport mutants of Arabidopsis and its implications for transport processes and engineering them in flowering plants will be discussed. Further, novel ongoing genomic and proteomic work into the molecular responses of Arabidopsis to ionising radiation and its implications for selecting plants from

Potato production on private plots contaminated by radionuclides

Energy Technology Data Exchange (ETDEWEB)

Bogdevitch, I.; Tarasiuk, S. [Belarusian Research Institute for Soil Science and Agrochemistry (BRISSA), Minsk (Belarus)

2004-07-01

Potatoes is one of the basis food products of man diet, especially in country area. Recent research has shown that {sup 137}Cs content in potato tubers does not exceed the permissible level at the potato growing on radioactive contaminated land in Belarus. However up to 240-300 kg of potatoes is consumed per man during year and potato yield determines significant share of the internal dose of radiation. Moreover, extra potato yield sold on market is forming the essential part of the rural family budget. Therefore the reducing of {sup 137}Cs content in potatoes and increasing of potato yield could be allowed to improve of quality life of rural inhabitants on contaminated areas. The application of protection measures on private plots are restricted by lack of the knowledge and financial deficit. The involvement of rural inhabitants in processes of self-rehabilitation and self-development could be a way to improve the quality life on radioactive contaminated territory There is strong motivation for inhabitants to increase the yield and to reduce the radionuclide concentration in potatoes. How to develop the conditions for the sustainable potato production by private producers on affected land? There are several factors to consider. Firstly, the rural inhabitants should be actively involved as initiators to improve their quality life. Secondly, the potato technology should be adopted to the local territory and tested by producers on radiological and economic efficiency. Thirdly, the common village initiatives should be developed for supplying by new varieties of seeds and fertilizers, selling of yield, consulting, crediting etc. The step-by-step solution of described strategy could allow improving and stabilizing the potato production by rural community. The training of rural people as an initial step was realized to transfer to the inhabitants the practical skills that can be used in their day-to-day life within framework of 'ETHOS-II' project. The

DNA polymorphisms revealed by the RAPD technique show differences between radionuclide-contaminated and uncontaminated mosquitofish populations

International Nuclear Information System (INIS)

Theodorakis, C.W.; Shugart, L.R.

1993-01-01

In 1977, approximately 250 Mosquitofish (Gambusia affines) were transplanted from a relatively uncontaminated site into a small pond on the Oak Ridge Reservation that is heavily contaminated with radionuclides. DNA polymorphisms, using the RAPD technique, were examined in order to determine if any genetic differentiation had occurred between the two populations. Also, fish from another radionuclide-contaminated population (White Oak Lake) and two unrelated non-contaminated populations were also examined. The RAPD (Randomly Amplified Polymorphic DNA) technique uses the polymerase chain reaction with a short oligonucleotide primer to produce DNA fragments of various lengths. When analyzed by gel electrophoresis, these fragments form banding patterns similar to DNA fingerprints. A total of 26 primers were used to produce DNA band patterns, many of which revealed population differences. In addition several primers revealed banding patterns which differentiated between the Crystal Springs and Pond 3513 populations. Furthermore, bands found at high frequency in Pond 3513 and White Oak Lake populations were absent or present at a lower frequency in the non-contaminated populations. For some primers, the contaminated populations showed more DNA bands per individual, and fish with more bands had fewer DNA strand breaks than the fish with fewer bands. These data will be discussed with relation to biomonitoring programs and evolution of resistance to genotoxins in natural populations

Effects of radionuclide contamination on leaf litter decomposition in the Chernobyl exclusion zone

Energy Technology Data Exchange (ETDEWEB)

Bonzom, Jean-Marc, E-mail: jean-marc.bonzom@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS, Cadarache, Bât. 183, BP 3, 13115 St Paul-lez-Durance (France); Hättenschwiler, Stephan [Centre d' Ecologie Fonctionnelle et Evolutive (CEFE UMR 5175, CNRS–Université de Montpellier–Université Paul-Valéry Montpellier–EPHE), 1919 Route de Mende, F-34293 Montpellier (France); Lecomte-Pradines, Catherine [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS, Cadarache, Bât. 183, BP 3, 13115 St Paul-lez-Durance (France); Chauvet, Eric [EcoLab, Université de Toulouse, CNRS, UPS, INPT, 118 Route de Narbonne, 31062 Toulouse cedex (France); Gaschak, Sergey [Chernobyl Center for Nuclear Safety, Radioactive Waste and Radioecology, International Radioecology Laboratory, 07100 Slavutych (Ukraine); Beaugelin-Seiller, Karine; Della-Vedova, Claire; Dubourg, Nicolas [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS, Cadarache, Bât. 183, BP 3, 13115 St Paul-lez-Durance (France); Maksimenko, Andrey [Chernobyl Center for Nuclear Safety, Radioactive Waste and Radioecology, International Radioecology Laboratory, 07100 Slavutych (Ukraine); and others

2016-08-15

The effects of radioactive contamination on ecosystem processes such as litter decomposition remain largely unknown. Because radionuclides accumulated in soil and plant biomass can be harmful for organisms, the functioning of ecosystems may be altered by radioactive contamination. Here, we tested the hypothesis that decomposition is impaired by increasing levels of radioactivity in the environment by exposing uncontaminated leaf litter from silver birch and black alder at (i) eleven distant forest sites differing in ambient radiation levels (0.22–15 μGy h{sup −1}) and (ii) along a short distance gradient of radioactive contamination (1.2–29 μGy h{sup −1}) within a single forest in the Chernobyl exclusion zone. In addition to measuring ambient external dose rates, we estimated the average total dose rates (ATDRs) absorbed by decomposers for an accurate estimate of dose-induced ecological consequences of radioactive pollution. Taking into account potential confounding factors (soil pH, moisture, texture, and organic carbon content), the results from the eleven distant forest sites, and from the single forest, showed increased litter mass loss with increasing ATDRs from 0.3 to 150 μGy h{sup −1}. This unexpected result may be due to (i) overcompensation of decomposer organisms exposed to radionuclides leading to a higher decomposer abundance (hormetic effect), and/or (ii) from preferred feeding by decomposers on the uncontaminated leaf litter used for our experiment compared to locally produced, contaminated leaf litter. Our data indicate that radio-contamination of forest ecosystems over more than two decades does not necessarily have detrimental effects on organic matter decay. However, further studies are needed to unravel the underlying mechanisms of the results reported here, in order to draw firmer conclusions on how radio-contamination affects decomposition and associated ecosystem processes. - Highlights: • The effects of radioactivity on

Effects of radionuclide contamination on leaf litter decomposition in the Chernobyl exclusion zone

International Nuclear Information System (INIS)

Bonzom, Jean-Marc; Hättenschwiler, Stephan; Lecomte-Pradines, Catherine; Chauvet, Eric; Gaschak, Sergey; Beaugelin-Seiller, Karine; Della-Vedova, Claire; Dubourg, Nicolas; Maksimenko, Andrey

2016-01-01

The effects of radioactive contamination on ecosystem processes such as litter decomposition remain largely unknown. Because radionuclides accumulated in soil and plant biomass can be harmful for organisms, the functioning of ecosystems may be altered by radioactive contamination. Here, we tested the hypothesis that decomposition is impaired by increasing levels of radioactivity in the environment by exposing uncontaminated leaf litter from silver birch and black alder at (i) eleven distant forest sites differing in ambient radiation levels (0.22–15 μGy h −1 ) and (ii) along a short distance gradient of radioactive contamination (1.2–29 μGy h −1 ) within a single forest in the Chernobyl exclusion zone. In addition to measuring ambient external dose rates, we estimated the average total dose rates (ATDRs) absorbed by decomposers for an accurate estimate of dose-induced ecological consequences of radioactive pollution. Taking into account potential confounding factors (soil pH, moisture, texture, and organic carbon content), the results from the eleven distant forest sites, and from the single forest, showed increased litter mass loss with increasing ATDRs from 0.3 to 150 μGy h −1 . This unexpected result may be due to (i) overcompensation of decomposer organisms exposed to radionuclides leading to a higher decomposer abundance (hormetic effect), and/or (ii) from preferred feeding by decomposers on the uncontaminated leaf litter used for our experiment compared to locally produced, contaminated leaf litter. Our data indicate that radio-contamination of forest ecosystems over more than two decades does not necessarily have detrimental effects on organic matter decay. However, further studies are needed to unravel the underlying mechanisms of the results reported here, in order to draw firmer conclusions on how radio-contamination affects decomposition and associated ecosystem processes. - Highlights: • The effects of radioactivity on ecosystem processes

Monitoring of Radionuclide Contamination in Food Samples in Malaysia due to Daiichi Reactor Accident in Fukushima, Japan

International Nuclear Information System (INIS)

Nurrul Assyikeen Mohd Jaffary; Abdul Kadir Ishak; Wo, Y.M.

2011-01-01

On March 11, 2011, a serious accident occurred in Daiichi nuclear reactor plant, Fukushima, Japan which caused radioactive materials been released into the atmosphere in the form of aerosols and dust particles. Sea water around the plant was also found contaminated with high radioactivity readings. These radioactive materials could be transported by the winds and ocean current across international borders and cannot be controlled by human. Besides a continuous monitoring activity of radionuclide content in the air and sea water that need to be conducted by the authorities, Malaysia should also control the entry of radionuclide through contaminated food ingestion by human. Radionuclide I-131, Cs-134 and Cs-137 were used as a counter-measure of pollution levels and counted with gamma spectrometry using standard analysis method suggested by AOAC International. In this paper, details description of the role of Radiochemical and Environment Group, Nuclear Malaysia who's responsible in analyzing the radioactivity in the food samples due to Fukushima Daiichi, Japan accident was included. Also discussed are the radioactivity limit adopted and analysis results from this monitoring. (author)

Nuclear-physical methods in macro- and microanalytical investigations of contamination with radionuclides at Semipalatinsk Nuclear Test Site

International Nuclear Information System (INIS)

Solodukhin, V.P.

2005-01-01

A complex of nuclear-physical methods developed in the Institute of Nuclear Physics of Kazakhstan National Nuclear Center for the investigations of the rate, character and peculiarities of contamination with radionuclides of the Semipalatinsk Nuclear Test Site (SNTS) is presented. The developed method combines both macroinvestigations (radionuclide analysis, NAA, XRFA, ESR- and NGR-spectroscopy) and microinvestigations (MS, micro-PIXE, electron microscopy). The results of the investigations at the main SNTS test sites 'Opytnoye pole' and 'Degelen' are presented. (author)

Comparison of two freshwater turtle species as monitors of radionuclide and chemical contamination: DNA damage and residue analysis

International Nuclear Information System (INIS)

Meyers-Schoene, L.; Shugart, L.R.; Beauchamp, J.J.; Walton, B.T.

1993-01-01

Two species of turtles that occupy different ecological niches were compared for their usefulness as monitors of freshwater ecosystems where both low-level radioactive and nonradioactive contaminants are present. The pond slider (Trachemys scripta) and common snapping turtle (Chelydra serpentina) were analyzed for the presence of 90 Sr, 137 Cs, 60 Co, and Hg, radionuclides and chemicals known to be present at the contaminated site, and single-strand breaks in liver DNA. The integrity of the DNA was examined by the alkaline unwinding assay, a technique that detects strand breaks as a biological marker of possible exposure to genotoxic agents. This measure of DNA damage was significantly increased in both species of turtles at the contaminated site compared with turtles of the same species at a reference site, and shows that contaminant-exposed populations were under more severe genotoxic stress than those at the reference site. The level of strand breaks observed at the contaminated site was high and in the range reported for other aquatic species exposed to deleterious concentrations of genotoxic agents such as chemicals and ionizing radiation. Statistically significantly higher concentrations of radionuclides and Hg were detected in the turtles from the contaminated area. Mercury concentrations were significantly higher in the more carnivorous snapping turtle compared with the slider; however, both species were effective monitors of the contaminants

Radionuclide contaminant analysis of small mammals at Area G, TA-54, 1994

International Nuclear Information System (INIS)

Biggs, J.; Bennett, K.; Fresquez, P.

1995-09-01

Small mammals were sampled at two waste burial sites (1 and 2) at Area G, TA-54 and a control site outside Area G (Site 3) to identify radionuclides that are present within surface and subsurface soils at waste burial sites, to compare the amount of radionuclide uptake by small mammals at waste burial sites to a control site, and to identify the primary mode of contamination to small mammals, either through surface contact or ingestion/inhalation. Three composite samples of at least five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. Samples were analyzed for 241 Am, 90 Sr, 238 Pu, 239 Pu, total U, and gamma spectroscopy (including 137 Cs). Significantly higher (parametric t-test at p = 0.05) levels of total U, 241 Am, 238 Pu, 239 Pu, and 40 K were detected in pelts as compared to the carcasses of small mammals at TA-54. Concentrations of other measured radionuclides in carcasses were nearly equal to or exceeded the mean concentrations in the pelts. The authors results show higher concentrations in pelts compared to carcasses which is similar to what has been found at waste burial/contaminated sites outside of Los Alamos National Laboratory. Site 1 had significantly higher (alpha = 0.05, F = 0.0095) total U concentrations in carcasses than Sites 2 and 3. Site 2 had significantly higher (alpha = 0.05, F = 0.0195) 239 Pu concentrations in carcasses than either Site 1 or Site 3. A significant difference in 90 Sr concentration existed between Sites 1 and 2 (alpha = 0.05, F = 0.0681) and concentrations of 40 K at Site 1 were significantly different from Site 3

Derivation of recommended limits for radionuclide contamination of foods by the FAO

International Nuclear Information System (INIS)

Wirth, E.; Mueller, M.K.

1986-01-01

As a consequence of the reactor accident at Chernobyl, USSR, various countries defined limits for radioactive contamination of foods at different levels. These limits ranged from a few Bq iodine 131 or cesium 134 + 137/kg (Malaysia and Canada) to more than 1000 Bq/kg (Great Britain and France). These variations in limits hindered the movement of foods in international trade. For this reason the FAO convened an Expert Consultation to derive 'action levels' below which neither intervention nor constraint would be justified in terms of international movement and trade in food and drink. These limits are to find application in cases of widespread environmental contamination after an accidental release of radionuclides. They are not to be applied in cases of local release, e.g. in the vicinity of nuclear facilities. The derivation of 'action levels' by the FAO was based on the recommendations issued by the International Commission of Radiological Protection (ICRP) in May 1985. According to this recommendation the committed dose equivalent for the whole body should not exceed 5 mSv in the first and 1 mSv in the consecutive years. For radionuclides that preferentially irradiate individual organs, e.g. I131 in the thyroid, the dose equivalent to a specified organ may be used to derive limiting values. For individual organs limiting doses of 50 mSv/a and 10 mSv/a respectively were chosen

Derivation of recommended limits for radionuclide contamination of foods by the FAO

Energy Technology Data Exchange (ETDEWEB)

Wirth, E; Mueller, M K [Institute for Radiation Hygiene, Federal Health Office, Neuherberg (Germany)

1986-07-01

As a consequence of the reactor accident at Chernobyl, USSR, various countries defined limits for radioactive contamination of foods at different levels. These limits ranged from a few Bq iodine 131 or cesium 134 + 137/kg (Malaysia and Canada) to more than 1000 Bq/kg (Great Britain and France). These variations in limits hindered the movement of foods in international trade. For this reason the FAO convened an Expert Consultation to derive 'action levels' below which neither intervention nor constraint would be justified in terms of international movement and trade in food and drink. These limits are to find application in cases of widespread environmental contamination after an accidental release of radionuclides. They are not to be applied in cases of local release, e.g. in the vicinity of nuclear facilities. The derivation of 'action levels' by the FAO was based on the recommendations issued by the International Commission of Radiological Protection (ICRP) in May 1985. According to this recommendation the committed dose equivalent for the whole body should not exceed 5 mSv in the first and 1 mSv in the consecutive years. For radionuclides that preferentially irradiate individual organs, e.g. I131 in the thyroid, the dose equivalent to a specified organ may be used to derive limiting values. For individual organs limiting doses of 50 mSv/a and 10 mSv/a respectively were chosen.

Decision making algorithm of the rehabilitation of agricultural lands contaminated with heavy natural radionuclides

International Nuclear Information System (INIS)

Khomutyinyin, Yu.V.; Yivanov, Yu.O.; Kirichenko, V.K.

2013-01-01

Problem of rehabilitation of agricultural land contaminated with heavy natural radionuclides ( 210 Pb, 210 Po, 226 Ra, 232 Th, 238 U) was considered. Algorithm of decision making support on advisability of rehabilitation of mentioned land was suggested. Proposed algorithm was tested on the base of agricultural farmlands located in the affected zone of Pridneprovsky Chemicals Plant and its tailing dumps

Radionuclide Retention in Concrete Wasteforms

Energy Technology Data Exchange (ETDEWEB)

Wellman, Dawn M.; Jansik, Danielle P.; Golovich, Elizabeth C.; Cordova, Elsa A.

2012-09-24

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of LLW and MLLW, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

Monitoring of Radionuclide Contamination in Food Samples in Malaysia due to Daiichi Reactor Accident in Fukushima, Japan

International Nuclear Information System (INIS)

Nurrul Assyikeen Mohd Jaffary; Wo, Y.M.; Abdul Kadir Ishak

2015-01-01

On March 11, 2011, a serious accident occurred in Daiichi nuclear reactor plant, Fukushima, Japan which caused radioactive materials been released into the atmosphere in the form of aerosols and dust particles. Sea water around the plant was also found contaminated with high radioactivity readings. These radioactive materials could be transported by the winds and ocean current across international borders and cannot be controlled by human. Thus, a continuous monitoring activity of radionuclide content in the air and sea water needs to be conducted by the authorities. In addition to radioactivity monitoring, Malaysia should also control the entry of contaminated food in order to prevent radionuclide ingestion by human. The radionuclide 131 I, 134 Cs and 137 Cs were used as a measure of pollution levels and counted with gamma spectrometry using standard analysis method suggested by AOAC International. In this paper, details description of the role of Radiochemical and Environment Group, Nuclear Malaysia who is responsible in analyzing the radioactivity in the food samples due to Fukushima Daiichi, Japan accident was included. The radioactivity limit adopted and analysis results from this monitoring were discussed. (author)

Radionuclides in the food chain

International Nuclear Information System (INIS)

Harley, J.H.; Schmidt, G.D.

1988-01-01

Radionuclides in the Food Chain reviews past experience in meeting the challenge of radionuclide contamination of foodstuffs and water sources and, in the wake of the reactor accidents at Chernobyl and Three Mile Island, presents current concepts and programs relating to measurement, surveillance, effects, risk management, evaluation guidelines, and control and regulatory activities. This volume, based on a symposium sponsored by the International Life Sciences Institute in association with the International Institute for Applied Systems Analysis, which brought together both radiation experts and food industry policymakers, examines such vital topics as structural problems in large-scale crisis-managment systems; dose assessment from man-made sources; international recommendations on radiation protection; airborne contamination, as well as aquatic and soilborne radionuclides; food-chain contamination from testing nuclear devices; long-term health effects of radionuclides in food and water supplies; and use of mathematical models in risk assessment and management. (orig.)

Phytoremediation: role of terrestrial plants and aquatic macrophytes in the remediation of radionuclides and heavy metal contaminated soil and water.

Science.gov (United States)

Sharma, Sunita; Singh, Bikram; Manchanda, V K

2015-01-01

Nuclear power reactors are operating in 31 countries around the world. Along with reactor operations, activities like mining, fuel fabrication, fuel reprocessing and military operations are the major contributors to the nuclear waste. The presence of a large number of fission products along with multiple oxidation state long-lived radionuclides such as neptunium ((237)Np), plutonium ((239)Pu), americium ((241/243)Am) and curium ((245)Cm) make the waste streams a potential radiological threat to the environment. Commonly high concentrations of cesium ((137)Cs) and strontium ((90)Sr) are found in a nuclear waste. These radionuclides are capable enough to produce potential health threat due to their long half-lives and effortless translocation into the human body. Besides the radionuclides, heavy metal contamination is also a serious issue. Heavy metals occur naturally in the earth crust and in low concentration, are also essential for the metabolism of living beings. Bioaccumulation of these heavy metals causes hazardous effects. These pollutants enter the human body directly via contaminated drinking water or through the food chain. This issue has drawn the attention of scientists throughout the world to device eco-friendly treatments to remediate the soil and water resources. Various physical and chemical treatments are being applied to clean the waste, but these techniques are quite expensive, complicated and comprise various side effects. One of the promising techniques, which has been pursued vigorously to overcome these demerits, is phytoremediation. The process is very effective, eco-friendly, easy and affordable. This technique utilizes the plants and its associated microbes to decontaminate the low and moderately contaminated sites efficiently. Many plant species are successfully used for remediation of contaminated soil and water systems. Remediation of these systems turns into a serious problem due to various anthropogenic activities that have

THE SCENARIOS APPROACH TO ATTENUATION-BASED REMEDIES FOR INORGANIC AND RADIONUCLIDE CONTAMINANTS

Energy Technology Data Exchange (ETDEWEB)

Vangelas, K.; Rysz, M.; Truex, M.; Brady, P.; Newell, C.; Denham, M.

2011-08-04

Guidance materials based on use of conceptual model scenarios were developed to assist evaluation and implementation of attenuation-based remedies for groundwater and vadose zones contaminated with inorganic and radionuclide contaminants. The Scenarios approach is intended to complement the comprehensive information provided in the US EPA's Technical Protocol for Monitored Natural Attenuation (MNA) of Inorganic Contaminants by providing additional information on site conceptual models and extending the evaluation to consideration of Enhanced Attenuation approaches. The conceptual models incorporate the notion of reactive facies, defined as units with hydrogeochemical properties that are different from surrounding units and that react with contaminants in distinct ways. The conceptual models also incorporate consideration of biogeochemical gradients, defined as boundaries between different geochemical conditions that have been induced by waste disposal or other natural phenomena. Gradients can change over time when geochemical conditions from one area migrate into another, potentially affecting contaminant mobility. A recognition of gradients allows the attenuation-affecting conditions of a site to be projected into the future. The Scenarios approach provides a stepwise process to identify an appropriate category of conceptual model and refine it for a specific site. Scenario materials provide links to pertinent sections in the EPA technical protocol and present information about contaminant mobility and important controlling mechanism for attenuation-based remedies based on the categories of conceptual models.

MOIRA: a computerised decision support system for the management of radionuclide contaminated freshwater ecosystems

International Nuclear Information System (INIS)

Gallego, Eduardo; Brittain, John E.; Hakanson, Lars; Heling, Rudie; Hofman, Dmitry; Monte, Luigi

2004-01-01

The radiation dose resulting from contamination of freshwater ecosystems due to the release of radioactive substances into the environment may be reduced by applying suitable countermeasures. Despite their benefits, intervention strategies may have detrimental effects of economic, ecological and social nature. Thus, it is of paramount importance to assess, by objective criteria, the global cost-benefit balance of different options. The MOIRA project (A MOdel based computerised system for management support to Identify optimal remedial strategies for Restoring radionuclide contaminated Aquatic ecosystems) has developed a user-friendly, computerised tool that will allow decision makers to choose optimal intervention strategies for freshwater ecosystems with different contamination scenarios. The aim of the paper is to briefly describe the main components of the MOIRA system and to demonstrate its application using real case based scenarios. (author)

Radionuclide contaminant analysis of rodents at a waste burial site, Los Alamos National Laboratory

International Nuclear Information System (INIS)

Biggs, J.R.; Bennett, K.D.; Fresquez, P.R.

1996-01-01

Small mammals were sampled at two waste burial sites (Sites 1 and 2) at Area G, TA-54, and a control site outside Area G (Site 3) to identify radionuclides that are present within surface and subsurface soils at waste burial sites, to compare the amount of radionuclide uptake by small mammals at waste burial sites to a control site, and to identify the primary mode of contamination to small mammals, either through surface contact or ingestion/inhalation. Three composite samples of at least five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. Samples were analyzed for americium ( 241 Am), strontium ( 90 Sr), plutonium ( 238 Pu and 239 Pu), total uranium (U), and examined by gamma spectroscopy (including cesium [ 137 Cs]). Significantly higher (parametric t-test at p = 0.05) levels of total U, 241 Am, 238 Pu, and potassium ( 40 K) were detected in pelts as compared to the carcasses of small mammals at TA-54. Concentrations of other measured radionuclides in carcasses were nearly equal to or exceeded the mean concentrations in the pelts. The results show higher concentrations in pelts compared to carcasses which is similar to what has been found at waste burial/contaminated sites outside of Los Alamos National Laboratory. Site 1 had significantly higher (alpha = 0.05, P = 0.0095) total U concentrations in carcasses than Sites 2 and 3. Site 2 had significantly higher (alpha = 0.05, P = 0.0195) 239 Pu concentrations in carcasses than either Site 1 or Site 3

Physicochemical characteristics of radionuclides associated with sediment from a contaminated fresh water stream

International Nuclear Information System (INIS)

Murdock, R.N.; Hemingway, J.D.; Jones, S.R.

1993-01-01

The relationships between concentrations of 241 Am, 137 Cs and 239,240 Pu and sediment particle size and geochemical species were examined for sediments taken from a freshwater stream contaminated by radioactive effluent from a low-level waste disposal site. Both 137 Cs and gross alpha concentrations were strongly correlated with the silt and clay content of the sediment, radionuclide concentrations following the order: clay>silt>sand. Positive correlations with organic content were also observed for both 137 Cs and gross alpha activity. These relationships, together with erosional and depositional characteristics obtained from streamflow data, largely explained the spatial variation in radionuclide concentrations in streambed sediments. Sequential extraction experiments showed that 137 Cs was mostly ''irreversibly'' bound to sediment particle, principally illitic clays, whereas 241 Am and 239,240 Pu were associated primarily with organic and oxy-hydroxy species within the sediments. (Author)

Radionuclide Retention in Concrete Wasteforms

Energy Technology Data Exchange (ETDEWEB)

Bovaird, Chase C.; Jansik, Danielle P.; Wellman, Dawn M.; Wood, Marcus I.

2011-09-30

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. The information present in the report provides data that (1) measures the effect of concrete wasteform properties likely to influence radionuclide migration; and (2) quantifies the rate of carbonation of concrete materials in a simulated vadose zone repository.

Assessing radiation doses to the public from radionuclides in timber and wood products

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-10-01

In the event of a nuclear accident involving the release of radionuclides to the biosphere the radioactive contamination of forests can become a significant potential source of public radiation exposure. Two of these accidents - the Kyshtim accident, Urals, USSR (now Russian Federation) in 1957 and the Chernobyl accident, USSR (now Ukraine), in 1986 - resulted in significant contamination of thousands of square kilometres of forested areas with mixtures of radionuclides including long lived fission products such as {sup 137}Cs and {sup 90}Sr. Measurements and modelling of forest ecosystems after both accidents have shown that, following initial contamination, the activity concentration of long lived radionuclides in wood gradually increases over one to two decades and then slowly decreases in the subsequent period. The longevity of the contamination is due to the slow migration and persistent bioavailability of radionuclides in the forest soil profile, which results in long term transfer into wood through the root system of the trees. Another source of contamination is from global radioactive fallout after nuclear weapons tests, but the level of contamination is much lower than that from, for example, the Chernobyl accident. For instance, the level of {sup 137}Cs in wood in Sweden is about 2-5 Bq kg{sup -1} from global fallout. Global values are very similar to the Swedish levels. In contrast, the level of {sup 137}Cs in Swedish wood due to Chernobyl is around 50 Bq kg{sup -1}. Levels in wood from some contaminated areas located in countries of the Former Soviet Union (FSU) are about one to two orders of magnitude higher than this. The data on {sup 137}Cs soil contamination within European territories, originating mainly from the Chernobyl accident, illustrate the scale of the problem. For comparison, residual {sup 137}Cs soil deposition in Europe from global radioactive fallout was in the range 1-4 kBq m{sup -2}. There is concern in several countries about the

Anthropogenic radionuclides in the environment

Energy Technology Data Exchange (ETDEWEB)

Hu, Q; Weng, J; Wang, J

2007-11-15

Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview of anthropogenic radionuclide contamination in the environment, as well as the salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current development that contribute to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) commercial fuel reprocessing; (5) geological repository of high-level nuclear wastes, and (6) nuclear accidents. Then, we summarize the geochemical behavior for radionuclides {sup 99}Tc, {sup 129}I, and {sup 237}Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment. Biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

Dosimetric Aspects of Personnel Skin Contamination by Radionuclides - Estimate of a Skin Dose, Monitoring and Interpretation of Results

International Nuclear Information System (INIS)

Husak, V.; Kleinbauer, K.

2001-01-01

Full text: On the basis of a critical comparison of literary data, tables are compiled of beta and gamma dose rate in mSvh -1 (kBqcm -1 ) to the basal layer of the skin at 0.07 mm depth from contamination by 75 radionuclides unsealed sources; radioactive substances are assumed to reside on the skin surface. The residence time needed for the estimate of the skin dose is calculated assuming that a residual activity per unit area of any radionuclide on the skin, which could not be removed by the repeated careful decontamination, is supposed to be eliminated with the biological half-life of 116 h as a consequence of the natural sloughing off of the skin. Radionuclides are divided into five groups according to the dose estimate in mSv (kBqcm -2 ): ≥250 (e.g. 32 P, 89 Sr, 137 Cs/ 137m Ba), 100-250 (e.g. 90 Y, 131 I, 186 Re), 10-100 (e.g. 35 S, 67 Ga, 200 Tl), 1-10 (e.g. 18 F, 51 Cr, 99m Tc), ≤1 (e.g. 63 Ni, 144 Pr, 238 U). If it is possible, doses can be determined more precisely by measuring the effective half-life of the residual activity on the contaminated area. Our dose estimates are approximately valid on the condition that, after decontamination, residual activity of radionuclides persists predominantly in the superficial layers of epidermis. This and further uncertainties connected with the dose assessment are discussed. Our tables can help to determine easily rough values of doses to personnel in contamination incidents and to interpret them in relation to regulatory derived limits. This work was supported by State Office for Nuclear Safety in Prague. (author)

Chemical speciation of radionuclides in contaminant plumes at the Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Champ, D.R.

1986-01-01

Experimental disposals of liquid and glassified wastes directly into the sands of the Perch Lake basin, Ontario, Canada, have resulted in the formation of well-defined subsurface contaminant plumes in the groundwater flow system. Using large volume water sampling techniques we have detected low concentrations of several long-lived radionuclides including isotopes of Pu, Am, Cm, Tc, I, Sr and Cs. The particulate and ionic speciation results from these studies support the conclusions of previous laboratory column studies that transport of radionuclides, particularly Cs and Pu, on particulates and/or colloids could be a significant mobilization mechanism in groundwater flow systems. We also propose, based on a comparison of the plume data with previous detailed studies on 60 Co that complexation reactions with natural as well as synthetic organic ligands can yield mobile anionic species of the actinides and lanthanides. Further detailed studies will be required to support this postulate. (author)

Radionuclide Retention in Concrete Waste Forms

Energy Technology Data Exchange (ETDEWEB)

Mattigod, Shas V.; Bovaird, Chase C.; Wellman, Dawn M.; Wood, Marcus I.

2010-09-30

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how waste form performance is affected by the full range of environmental conditions within the disposal facility; the process of waste form aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of waste form aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the waste forms come in contact with groundwater. The information presented in the report provides data that 1) quantify radionuclide retention within concrete waste form materials similar to those used to encapsulate waste in the Low-Level Waste Burial Grounds (LLBG); 2) measure the effect of concrete waste form properties likely to influence radionuclide migration; and 3) quantify the stability of uranium-bearing solid phases of limited solubility in concrete.

CRITERIA FOR REHABILITATION OF FACILITIES AND TERRITORIES CONTAMINATED WITH RADIONUCLIDES AS A RESULT OF PAST ACTIVITIES: PART 1. THE CHOICE OF INDICATORS FOR JUSTIFICATION OF THE CRITERIA FOR REHABILITATION

Directory of Open Access Journals (Sweden)

I. K. Romanovich

2016-01-01

Full Text Available The article examines issues of rehabilitation of facilities and territories contaminated by the man-made and natural radionuclides as a result of past activities of enterprises of nuclear and non-nuclear industries. Rehabilitated facilities and territories contaminated with radionuclides as a result of past activities of enterprises must meet criteria based on the analysis of requirements of existing normative legislative documents in the field of radiation protection of the population taking into account the recommendations of international organizations that are justified dose quantities and derivative indicators used in criteria setting. It is shown that the criteria for rehabilitation of facilities and territories contaminated by man-made radionuclides as a result of past activities, should be the same regardless of whether the contamination occurred as a result of planned activities of the enterprise or due to unauthorized activities. For these situations, the criteria for rehabilitation should be based on dose quantities and derived indicators of the residual contamination of the environment after rehabilitation. Only indicators of radiation safety of the environment can be used in almost all cases for justification of the criteria for rehabilitation of facilities and territories contaminated by natural radionuclides. The article shows that such approaches are applicable not only to environmental media contaminated as result of past activities of enterprises of traditional non-nuclear industries but the mining of uranium and thorium ores. From the standpoint of modern classification of industrial waste with a high concentration of natural radionuclides, the characteristics of these wastes according to their potential radiation hazard to people and the environment are identical.

Long-term strategy of rehabilitation of Byelorussian territories contaminated by radionuclides

International Nuclear Information System (INIS)

Kenik, I.; Rolevich, I.; Gurachevsky, V.; Poplyko, I.; Ageets, V.

1999-01-01

Thus, by applying a combination of countermeasures on various technological stages of agricultural production, one can control the process of production and the use of agricultural products, ensuring the production of major foodstuffs in contaminated regions in quantities sufficient for the population living there and in accordance with the consumption standards, and also corresponding to the standards of ecological and radiation safety. The following works in agriculture will require investment by the state: selection of new varieties of agricultural crops and creation of new technologies; development of seed production in a way allowing to reduce the contamination of the final product with radionuclides; refinement of the maps showing contamination of arable land with 137 Cs and 90 Sr based on the constant monitoring; improvement of pastures and hay fields for the private livestock. The following works are needed to stabilize livestock production and ensure production of clean livestock products in contaminated areas: increase the volume of production for major products made of livestock; equip livestock farms with machinery; improve production of forage at the farms by enhancing the structure of fields sown with forage crops, achieving higher yields, introducing progressive methods of harvesting and storing of forage, introduction of mineral additives and biologically active substances. The realistic assessment of the radioactive situation and its forecast lead to the conclusion that the contaminated territory can be rehabilitated with the help of the combined application of the above mentioned organisational and special measures leading to the reduction of the individual dose to 1 mSv per year. (authors)

Bacterial microflora characteristics of plant samples from contaminated by radionuclides Chernobyl area

International Nuclear Information System (INIS)

Zelena, Pavlina; Shevchenko, Julia; Molozhava, Olha; Berezhna, Valentina; Shylina, Julia; Guscha, Mykola

2015-01-01

Two serious nuclear accidents during the last quarter century (Chernobyl, 1986 and Fukushima, 2011) contaminated large agricultural areas with radioactivity. In radioactive areas all components of ecosystems, including microorganisms, exposed to ionizing radiation. The aim of this study was isolation and identification of dominant bacteria from plant samples, which were collected from the area of radioactive contamination and to compare it with bacteria isolated from plant collected in a non-radioactive area by their qualitative composition, physiological, biochemical and pathogenic characteristics. Bacteria were isolated from plant samples grown in a radioactive field located 5 km from the Chernobyl Nuclear Power Plant (CNPP). Physiological, biochemical and pathogenic properties were characterized from nine pure bacterial isolates. The common features of bacteria from radionuclide contaminated plant samples were increased synthesis of mucus and capsule creation. It was found that all selected isolates produce catalase, therefore, bacteria were resistant to oxidative stress. The increased pathogenicity of most bacteria isolated from the plant grown in radioactive Chernobyl area compare to the isolates from the plant without radioactive contamination was established from the phytopathogenic tests. Consequently, bacterial isolates from the plants grown in the radioactive environment tends to dominate enterobacteria similar to agents of opportunistic infections. (author)

Characterization of the near-surface radionuclide contamination associated with the bathtub effect at Solid Waste Storage Area 4, Oak Ridge National Laboratory, Tennessee

International Nuclear Information System (INIS)

Melroy, L.A.; Huff, D.D.; Farrow, N.D.

1986-06-01

Solid Waste Storage Area 4 (SWSA-4) at the Oak Ridge National Laboratory (ORNL) was studied to determine the extent of near-surface radionuclide contamination associated with the bathtub effect in low-lying trenches. A surface survey of the low-elevation portion of the burial ground was conducted to identify areas where the bathtub effect had resulted in surface contamination. Using this initial survey as a guide, 15 soil cores, each approximately 3 m deep, were taken to determine the depth to which contamination had spread and to help identify an contamination plumes. Results showed that two areas of surface radionuclide contamination exist, one located between the western end of the SWSA-4 tributary and the edge of the burial ground, the other located just north of the tributary below the central paved runoff channel. In addition, some downward migration of the solutes has occurred. However, the penetration depth for 90 Sr seems to be generally less than 2.7 m

Assessing radiation doses to the public from radionuclides in timber and wood products

International Nuclear Information System (INIS)

2003-10-01

In the event of a nuclear accident involving the release of radionuclides to the biosphere the radioactive contamination of forests can become a significant potential source of public radiation exposure. Two of these accidents - the Kyshtim accident, Urals, USSR (now Russian Federation) in 1957 and the Chernobyl accident, USSR (now Ukraine), in 1986 - resulted in significant contamination of thousands of square kilometres of forested areas with mixtures of radionuclides including long lived fission products such as 137 Cs and 90 Sr. Measurements and modelling of forest ecosystems after both accidents have shown that, following initial contamination, the activity concentration of long lived radionuclides in wood gradually increases over one to two decades and then slowly decreases in the subsequent period. The longevity of the contamination is due to the slow migration and persistent bioavailability of radionuclides in the forest soil profile, which results in long term transfer into wood through the root system of the trees. Another source of contamination is from global radioactive fallout after nuclear weapons tests, but the level of contamination is much lower than that from, for example, the Chernobyl accident. For instance, the level of 137 Cs in wood in Sweden is about 2-5 Bq kg -1 from global fallout. Global values are very similar to the Swedish levels. In contrast, the level of 137 Cs in Swedish wood due to Chernobyl is around 50 Bq kg -1 . Levels in wood from some contaminated areas located in countries of the Former Soviet Union (FSU) are about one to two orders of magnitude higher than this. The data on 137 Cs soil contamination within European territories, originating mainly from the Chernobyl accident, illustrate the scale of the problem. For comparison, residual 137 Cs soil deposition in Europe from global radioactive fallout was in the range 1-4 kBq m -2 . There is concern in several countries about the potential radiation exposure of people from

Characterization of surface water contaminants in the Clinch River and Poplar Creek

International Nuclear Information System (INIS)

Ford, C.; Madix, S.; Rash, C.

1995-01-01

Surface waters in the Clinch River and Poplar Creek have been contaminated by activities on the DOE's Oak Ridge Reservation throughout the more than 50 year history of Oak Ridge. Though the Clinch River and Poplar Creek drainage areas are contaminated with heavy metals, organics and radionuclides, public access to these sites is not restricted. The investigation, divided into discrete studies, was tailored to provide a statistically sound picture of contaminants and aqueous toxicity in Poplar Creek, investigate contaminant remobilization from sediments, and determine contaminant levels during a series of ''worst-case'' events. Results for Poplar Creek indicate that average contaminant values were below levels of concern for human health and ecological risk, though contaminant distributions suggest that episodic events contribute sufficiently to system contaminant levels to be of concern. Additionally, water column contaminant levels were significantly higher in particle deposition areas rather than at known contaminant sources. Levels of organic compounds in reference areas to Poplar Creek exceeded those in the Poplar Creek study area. In the Clinch River and Poplar Creek, statistical differences in metal and radionuclide levels from known contaminated areas confirmed previous results, and were used to independently distinguish between sites. Contaminant concentrations were elevated in association with sediments, though no distinction between deposition and remobilization could be made. Due to elevated contaminant levels, and some unexpected contaminant distributions, sites in Poplar Creek and off-channel embayments of the Clinch River were identified that will require additional characterization

Modeling of the fate of radionuclides in urban sewer systems after contamination due to nuclear or radiological incidents

DEFF Research Database (Denmark)

Urso, L.; Kaiser, J.C.; Andersson, Kasper Grann

2013-01-01

After an accidental radioactive contamination by aerosols in inhabited areas, the radiation exposure to man is determined by complex interactions between different factors such as dry or wet deposition, different types of ground surfaces, chemical properties of the radionuclides involved and buil...

Human radiation dose resulting from forests contaminated by radionuclides: generic model and applications to the Chernobyl ecosystems

International Nuclear Information System (INIS)

Linkov, I.; Harvard Univ., Cambridge, MA; Schell, W.R.

1996-01-01

Forest ecosystems have been found to contribute significantly to the human radiation dose in the intermediate and long teens following radionuclide releases. Evaluation of the internal and external radiation dose for these critical population groups requires knowledge of radionuclide transport processes in forest ecosystems, as well as the extent of forest utilization by these populations. The high complexity of the problem requires the use of models to define and analyze the properties of the forest as well as to evaluate the ecosystem response to possible human intervention. A generic FORESTPATH model is used to calculate the internal and external radiation doses for different critical groups of consumers at different times following radionuclide release. The model is tested using the information available for contaminated forests in Belarus. Uncertainty of the model predictions are estimated by means of Monte-Carlo simulations. (author)

Radioresistance of populations of bank voles Clethrionomys glareolus in radionuclide-contaminated areas

International Nuclear Information System (INIS)

Il'enko, A.I.; Krapivko, T.P.

1994-01-01

Contamination of extended territories with radionuclides renders the monitoring of natural populations in their habitats an important work to be done in order to determine the directions of evolution caused by long-term exposure to ionizing radiation. In view of this, many years of field and experimental radioecological studies were devoted to animal populations that inhabit the territories contaminated with 137 Cs after the Chernobyl Power Plant disaster. Special emphasis was placed on the investigation of the time course of radiosensitivity of mammalian populations over several generations as a general index of adaptive processes developing in an area with an elevated radiation background. The authors monitored the population of the European bank vole, a species known for its high spontaneous resistance to radiation. In optimal environmental conditions, it has LD 50/30 = 9.7 Gy. The reaction of bank vole populations to radioactive contamination of their environment primarily increases the rate of variation of sensitivity to ionizing radiation. This results in a continuous increase in the radioresistance of the populations to a certains table level. The findings suggest that adaptive processes occur in natural mammalian populations subjected to chronic ionizing irradiation

Continuous measurements of natural radionuclides on air-borne dust using β-α correlated events. Towards on-line detection of artificial radionuclides in nuclear-fuel reprocessing and its related facilities

International Nuclear Information System (INIS)

Hashimoto, Tetsuo; Ishiyama, Hisanobu; Itou, Shigeki

2008-01-01

On the highly sensitive and on-line detection for the contamination of artificial nuclides, much attention has been paid to the elimination of significant problem due to 222 Rn-progenies. A phosfich-type α- and β-ray radiation counter, which was fixed just above the dust-collecting filter paper within a space in a few mm, provides both α- and β-ray pulses during continuous collection of air-borne dust. Both pulse input times were registered into the memory buffer in a pulse time interval analyzing (TIA) system, followed rapidly by the data processing using MTA (multiple TIA) method. Resultant β-α TIA-spectrum (or decay-curve of β-α correlated events) and changes of α- and β-counting rates were displayed instantly on a PC-display with 1 μs time resolution using installed softwares. Thus, three practical values, including β-α correlated event rates (n αβ ), α-(n α ), and β-ray counting rates (n β ) were available from the present TIA-measurement system. A uranium deposited source (as mixture of α- and β-ray emitters), uranium mineral powder sample, and 226 Ra-source (as β-source) showed negligible contribution to β-α correlated events in TIA-spectrum, giving constant α/β counting ratios. In the case of air-borne dust samples, the β-α correlated events in TIA-spectrum showed certainly a presence of 164 μs decay-curve due to 214 Po, based on successive decay process such as 241 Bi(β) → 214 Po(α:T 1/2 =164 μs)→. By using three measuring values, new parameters, R α and R β [equal to (n α or n β ) * (n α + n β )/n αβ ], have been introduced for the highly sensitive and real-time indicators of contamination owing to artificial nuclides, even under the inevitable existence of 222 Rn progenies in the air-borne dust sample. The present radiation measurement system, combined with β-α correlated events, has been proved to be useful for the detection of extremely small contamination with artificial α-nuclides as well as �

Toward zero waste events: Reducing contamination in waste streams with volunteer assistance.

Science.gov (United States)

Zelenika, Ivana; Moreau, Tara; Zhao, Jiaying

2018-03-22

Public festivals and events generate a tremendous amount of waste, especially when they involve food and drink. To reduce contamination across waste streams, we evaluated three types of interventions at a public event. In a randomized control trial, we examined the impact of volunteer staff assistance, bin tops, and sample 3D items with bin tops, on the amount of contamination and the weight of the organics, recyclable containers, paper, and garbage bins at a public event. The event was the annual Apple Festival held at the University of British Columbia, which was attended by around 10,000 visitors. We found that contamination was the lowest in the volunteer staff condition among all conditions. Specifically, volunteer staff reduced contamination by 96.1% on average in the organics bin, 96.9% in the recyclable containers bin, 97.0% in the paper bin, and 84.9% in the garbage bin. Our interventions did not influence the weight of the materials in the bins. This finding highlights the impact of volunteers on reducing contamination in waste streams at events, and provides suggestions and implications for waste management for event organizers to minimize contamination in all waste streams to achieve zero waste goals. Copyright © 2018. Published by Elsevier Ltd.

Water hyacinth for phytoremediation of radioactive waste simulate contaminated with cesium and cobalt radionuclides

International Nuclear Information System (INIS)

Saleh, H.M.

2012-01-01

Highlights: ► Phytoremediation of radioactive wastes containing 137 Cs and 60 Co radionuclides. ► Using water hyacinth for radioactive waste treatment. ► Bioaccumulation of radionuclides from radioactive waste streams. ► Factors affecting bioaccumulation of 137 Cs and 60 Co using floating plants. - Abstract: Phytoremediation is based on the capability of plants to remove hazardous contaminants present in the environment. This study aimed to demonstrate some factors controlling the phytoremediation efficiency of live floating plant, water hyacinth (Eichhornia crassipes), towards the effluents contaminated with 137 Cs and/or 60 Co. Cesium has unknown vital biological role for plant while cobalt is one of the essential trace elements required for plant. The main idea of this work i.e. using undesirable species, water hyacinth, in purification of radiocontaminated aqueous solutions has been receiving much attention. The controlling factors such as radioactivity concentration, pH values, the amount of biomass and the light were studied. The uptake rate of radiocesium from the simulated waste solution is inversely proportional to the initial activity content and directly proportional to the increase in mass of plant and sunlight exposure. A spiked solution of pH ≈ 4.9 was found to be the suitable medium for the treatment process. The uptake efficiency of 137 Cs present with 60 Co in mixed solution was higher than if it was present separately. On the contrary, uptake of 60 Co is affected negatively by the presence of 137 Cs in their mixed solution. Sunlight is the most required factor for the plant vitality and radiation resistance. The results of the present study indicated that water hyacinth may be a potential candidate plant of high concentration ratios (CR) for phytoremediation of radionuclides such as 137 Cs and 60 Co.

Radionuclide transfer from contaminated field to crops

International Nuclear Information System (INIS)

Ohmomo, Yoichiro; Tanaka, Giichiro

1987-03-01

Since the policy for land disposal of radioactive wastes were proposed, the importance of terrestrial radioecology has been re-recognized in Japan. The National Institute of Radiological Sciences (NIRS) held a Two-Day Seminar concerning terrestrial transfer of radionuclides. This is a compilation of papers presented at the seminar. The purpose of the seminar is twofold: firstly, to raise basic problems concerning transfer of not only radionuclides but also elements into crops, as well as to present NIRS's studies on radionuclide transfer; and secondly, to discuss in depth the topics about possible transfer of I-129 into rice plant arising from the commercial fuel reprocessing plant, the construction of which is under planning. Finally, general discussion of further issues on radioecology is given. (Namekawa, K.)

Structural-genetic approach to analysis and mapping of Chernobyl's radionuclide contamination field

International Nuclear Information System (INIS)

Proskura, N.I.; Bujkov, M.; Nagorsky, V.A.; Tepikin, V.; Poletaev, V.; Solyanke, E.G.; Shkvorets, O.Y.; Shestopalov, V.M.; Skvortsov, V.

1997-01-01

As a main tool for revealing and interpreting the internal structure of radionuclide contamination field, around the Chernobyl NPP the reliable and validated detailed scale maps of contamination densities could serve. Such maps should have, on the one hand, a high enough density of initial observation points (not less than 1 to 10 points per 1 sq.cm. of final map) and, on the other hand, a high representativeness of each observation point, i.e. reliability of presentation of its vicinity (0.1 to 1 sq.km). The available analytical data files of soil sampling in the exclusion zone conform neither to the first requirement, nor to the second one: real density of sampling does not exceed 0-2 to 0.5 points per 1 sq.m, and the representativeness of obtained results has a typical variation from medium values (in the neighbourhood of 0.1 to 1 sq.km) to 3 to 5 times

Border-line neuro psychic disturbances in children and teenagers living on the territory contaminated with radionuclides

International Nuclear Information System (INIS)

Bazyl'chik, S. V.

1993-01-01

Spread of the border-line neuro psychic disturbances in children and teenagers aged 10-16 living in the districts contaminated with radionuclides was studied. A marked increase of psychic disturbances, particularly in girls, attributed to the growth of neurotic and neurosis-like disorders as compared with the control group was revealed. Asthenic type disorders prevailed in derangement structure. 7 refs., 1 tab

Radionuclide Retention in Concrete Wasteforms - FY13

Energy Technology Data Exchange (ETDEWEB)

Snyder, Michelle MV; Golovich, Elizabeth C.; Wellman, Dawn M.; Crum, Jarrod V.; Lapierre, Robert; Dage, Denomy C.; Parker, Kent E.; Cordova, Elsa A.

2013-10-15

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of low-level waste and mixed low-level waste, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

Geographical-radioecological aspects of nuclear energy exploitation and environment contamination by man-made radionuclides in Russian Federation

International Nuclear Information System (INIS)

Kurucova, S.; Blazik, T.; Kuruc, J.

2005-01-01

Radioactive contamination of the environment is one of the most dangerous forms of environmental pollution in Russian Federation. The aim of this work was to localize and analyse places of nuclear energy exploitation for peaceful and military purposes in Russian Federation, in aim to find out whether observed places are potential or real sources of contamination of Russian environment by man-made radionuclides. Nuclear activities in nuclear industry enterprises and research organizations, in Russian Northern fleet, Russian Pacific Fleet, Russian civilian nuclear fleet and in nuclear power plants were analysed and the places where the nuclear explosions were carried out were localized. In contaminated regions the goal was to analyse geographical and some radioecological aspects of contamination of environment. Great part of Russian territory has been subjected to some form of radioactive contamination, mainly because of large radiation accidents in Mayak Production Association (PA) in the Urals (1949-1956, 1957 and 1967) and in Chernobyl Nuclear Power Plant (1986). The largest region in Russian Federation with environment contaminated by man-made radionuclides is region of Chernobyl NPP accident influence, which is situated in central, densely populated and economically relatively good developed part of Russian Federation where the agriculture has an important role. The most contaminated administrative units in region are Bryansk Region, Kaluga Region, Oryol Region and Tula Region where high soil density of cesium-137 are observed. Present radioecological situation in this region is analysed. By analysing of dynamics of demographic indicators in four most contaminated regions authors found out similar trends with Russian nationwide indicators and with indicators for Central Federal District but much more unfavourable values were observed in four regions, particularly in Tula Region. Health situation of liquidators and of affected population who live in contaminated

40 CFR 141.66 - Maximum contaminant levels for radionuclides.

Science.gov (United States)

2010-07-01

... beta particle and photon radioactivity from man-made radionuclides in drinking water must not produce.../year). (2) Except for the radionuclides listed in table A, the concentration of man-made radionuclides... may make this technology too complex for small surface water systems. e Removal efficiencies can vary...

The vertical distribution of radionuclides in a Ribble Estuary saltmarsh: transport and deposition of radionuclides

International Nuclear Information System (INIS)

Brown, J.E.; McDonald, P.; Parker, A.; Rae, J.E.

1999-01-01

Routine discharges of low-level liquid radioactive waste by British Nuclear Fuels plc (BNFL) at Sellafield and Springfields have resulted in enhanced levels of radionuclides in sediments of the Ribble Estuary, NW England, UK. Variations in radionuclide concentrations ( 137 Cs, 230 Th, and 239240 Pu) with depth in a mature saltmarsh core were analysed in order to investigate historical discharge trends and waste-dispersal mechanisms. Core samples from Longton/Hutton Marsh were analysed by gamma-spectrometry and α-spectrometry for radionuclides and by laser granulometry to establish grain-size variations with depth. Distinct subsurface maxima were present for 137 Cs and 239240 Pu with activities as high as 4500 Bq kg -1 for 137 Cs and 600 Bq kg -1 for 239240 Pu. Thorium-230 exhibited complex activity profiles with depth, specific activities ranging between 200 and 2400 Bq kg -1 . The vertical distributions of Sellafield-derived radionuclides ( 137 Cs and 239240 Pu) in mature saltmarsh deposits reflect the time-integrated discharge pattern from Sellafield, implying a transport mechanism that has involved the mixing of sediment labelled with radioactivity from recent discharges and sediment labelled from historical discharge events before deposition. A mechanism involving the transport of contaminated silt therefore seems to dominate. The vertical distribution of Springfields-derived 230 Th in the same areas reflects the annual gross-α discharge pattern from BNFL Springfields. In contrast to the Sellafield-derived radionuclides, a fairly rapid transport mechanism from source to sink is implied, with little or no time for mixing with radionuclides discharged years earlier. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Decomissioning of nuclear reactors - methods for calculation of radionuclide inventories in contaminated BWR systems

International Nuclear Information System (INIS)

Lundgren, K.

1991-01-01

The purpose of the study has been to develop and demonstrate calculation models for the prediction of radionuclide inventories in contaminated systems in the Nordic BWRs at the time of decommissioning. Oskarshamn 2 was selected as reference reactor for the study. The study is divided in radionuclide inventories of activated corrosion products, and inventories of fission products and actinides from leaking fuel. The study is restricted to contamination outside the reactor pressure vessel. Inventories of activated corrosion products on primary system surfaces were predicted with the ABB Atom computer code BKM-CRUD. The calculations were performed for an extended operation time up to year 2010 for the nuclides Co60, Co58, Zn65 and Mn54. A special set of calculations were also made covering the non-standard nuclides Fe55, Ni59, No63 and Mo93. ABB Atom has carried out a comprehensive program on shutdown dose rates and activity measurements in delivered BWRs. The resulting data base have been used in the study to derive conversion factors for evaluation of contamination levels in secondary systems from the BKM-CRUD results for primary systems. Fission products and actinides were treated by defining two different fuel leakage scenarios. The first one corresponds to a rather stable situation, with an average leakage rate of 1 'standard pin hole' (i.e. 2 MBq/s Xe133). The second scenario means more severe fuel leakage every 10 years (200 MBq/s Xe133). The radioactive inventories in different part of the plant were calculated by combining the surface areas with the calculated contamination levels in the different systems. The uncertainty in total activity inventory has been estimated to not exceed a factor of 2. The uncertainty in total activity inventory has been to not exceed a factor of 2. The estimated inventories in this study has been compared to the results from other studies, and a reasonable agreement was achieved

Influence the technogenic disaster at radionuclide contaminated Chernobyl zone on transgeneration changes of plants

International Nuclear Information System (INIS)

Rashydov, N.

2017-01-01

Some of the territories have naturally increased level of radiation as areas of native radioecological anomalies, but others were polluted as a result of nuclear weapon testing, nuclear waste leakage, and nuclear power plants disasters, such as Chernobyl nuclear power plant (CNPP) and Fukushima. Eventually, the large areas have been strong contaminated with radioactivity isotopes for long term. Despite more than thirty years aftermath the explosion of the CNPP accident, the problems coming from the high radionuclide contamination of the environment and the effects of chronic radiation on living organisms still remain relevant. Because the recent tragedy at the Fukushima Nuclear Power Plant in Japan is chillingly reminiscent of the world's worst nuclear disaster at Chernobyl, Ukraine in 1986. Our research addressing the effects of chronic ionizing radiation on plants, the ongoing success of plants adaptation and transgeneration changes in radio-contaminated Chernobyl area was revealed. The focus our investigation is on a role of the small dose chronic radiation due to plant biodiversity processes because it is a common adverse environmental toxicology factor. In order to characterize proteomes of plants adapting to biodiversity at radio-contaminated Chernobyl area we established non-radioactive and radio-contaminated experimental fields.

Rapid determination of radionuclide activity concentrations in contaminated drinking water

International Nuclear Information System (INIS)

Medley, P.; Ryan, B.; Bollhofer, A.; Martin, P.; International Atomic Energy Agency, Vienna

2007-01-01

As a result of an incident at the Ranger Uranium mine in which drinking water was contaminated with process water, it was necessary to perform quick analysis for naturally occurring uranium and thorium series radionuclide activity concentrations, including 226Ra, 210Pb, 210Po, U and Th isotopes. The methods which were subsequently used are presented here. The techniques used were high-resolution gamma spectrometry, Inductively Coupled Plasma Mass Spectrometry (ICPMS) and high-resolution alpha spectrometry. Routine methods were modified to allow for rapid analyses on priority samples in 1-2 days, with some results for highest priority samples available in less than 1 day. Comparison of initial results obtained through standard procedures, is discussed. An emphasis is placed on high-resolution alpha spectrometry of major alpha-emitting nuclides, specifically 226Ra, 230Th and 238U. The range of uranium concentrations in the samples investigated was from background levels to 6.6ppm. Implications for radiological dose assessment in contamination incidents involving process water are presented. The worst-case scenario for the incident at Ranger Uranium Mine indicates that the maximum committed effective dose to workers was well below the ICRP limit for worker-related dose and below the dose limit for a member of the public, with 230Th being the highest contributor

Assessment of radionuclide and metal contamination in a thorium rich area in Norway.

Science.gov (United States)

Popic, Jelena Mrdakovic; Salbu, Brit; Strand, Terje; Skipperud, Lindis

2011-06-01

The Fen Central Complex in southern Norway, a geologically well investigated area of magmatic carbonatite rocks, is assumed to be among the world largest natural reservoirs of thorium ((232)Th). These rocks, also rich in iron (Fe), niobium (Nb), uranium ((238)U) and rare earth elements (REE), were mined in several past centuries. Waste locations, giving rise to enhanced levels of both radionuclides and metals, are now situated in the area. Estimation of radionuclide and metal contamination of the environment and radiological risk assessment were done in this study. The average outdoor gamma dose rate measured in Fen, 2.71 μGy h(-1), was significantly higher than the world average dose rate of 0.059 μGy h(-1). The annual exposure dose from terrestrial gamma radiation, related to outdoor occupancy, was in the range 0.18-9.82 mSv. The total activity concentrations of (232)Th and (238)U in soil ranged from 69 to 6581 and from 49 to 130 Bq kg(-1), respectively. Enhanced concentrations were also identified for metals, arsenic (As), lead (Pb), chromium (Cr) and zinc (Zn), in the vicinity of former mining sites. Both radionuclide and heavy metal concentrations suggested leaching, mobilization and distribution from rocks into the soil. Correlation analysis indicated different origins for (232)Th and (238)U, but same or similar for (232)Th and metals As, Cr, Zn, nickel (Ni) and cadmium (Cd). The results from in situ size fractionation of water demonstrated radionuclides predominately present as colloids and low molecular mass (LMM) species, being potentially mobile and available for uptake in aquatic organisms of Norsjø Lake. Transfer factors, calculated for different plant species, showed the highest radionuclide accumulation in mosses and lichens. Uptake in trees was, as expected, lower. Relationship analysis of (232)Th and (238)U concentrations in moss and soil samples showed a significant positive linear correlation.

Determination of radionuclide concentrations in animal feedstuffs for use following a nuclear emergency

International Nuclear Information System (INIS)

Hwang, W. T.; Ser, K. S.; Kim, E. H.; Choi, Y. K.; Han, M. H.; Choi, Y. H.

2001-01-01

The optimized derived intervention levels for animal products were evaluated based on cost-benefit analysis. From these results, the radionuclide concentrations in animal feedstuffs for use were derived. It was shown that radionuclide concentrations in animal feedstuffs for use depend strongly on animal products, radionuclides and feeding period. In case of the contaminated feedstuffs with long-lived radionuclides ( 137 Cs, 90 Sr), the feedstuffs with lower contamination should be supplied to animals with increase of feeding period due to the accumulation of radionuclides in animal products. While, in case of the contaminated feedstuffs with short-lived radionuclides ( 131 I), the feeding of higher contaminated feedstuffs was possible with increase of feeding period due to radionuclide decay. It was shown that 137 Cs concentration was lower than 90 Sr concentration in animal feedstuffs for use. It is primarily due to the higher feed-animal products transfer factor of 137 Cs

Radioprotective effect of microelements at the territories contaminated by radionuclides

International Nuclear Information System (INIS)

Gudkov, I.N.

2007-01-01

The most radioactively contaminated region of Ukrainian and Byelorussian Palesse belongs to a biogeochemical province where soils, plants, and, accordingly, forage for animals and food stuffs are poor with biologically important microelements - iodine, zinc, copper, cobalt, fluorine, manganese, lithium, boron. It is a cause of specific diseases of plants, animals and people known as hypomicroelementhoses. Carrying out the radioprotective measures (countermeasures), particularly liming of soils and applying the heightened doses of phosphoric fertilizers, reduces transfer of radionuclides from soil to plants and also elements of mineral nutrition included the microelements. It aggravates the deficiency of microelements following the decrease of productivity and quality of production in plant and animal breeding and exacerbation of the mentioned diseases. It is known, that many microelements have radioprotective properties, and same of them can influence on uptake of other elements in plants. Therefore, considering the situation with microelements, we can expect of their role in radiation protection of living organisms in a zone affected by accident in Chernobyl NPP. It was shown the applying (root injection) of zinc, manganese, cobalt, copper in the sulfates and chlorides (4-6 kg of metal per hectare) on soddy-podsolic soil, reduced the Sr 90 and Cs 137 transfer factor. Zinc was the most effective: the content of both radionuclides in grain of oats and lupine decreased in 1,5-2 times. Lesser efficiency was observed with manganese and cobalt, much less - with copper. Moreover, in some cases the increase of Sr 90 accumulation was observed. Influence of microelements was stronger in variants without fertilizers, than with their heightened doses. It happened because, firstly, fertilizers contain some various microelements. And, secondly, in favorable conditions for growth and development of plants provided by fertilizers, the action of both factors, positive, and

Monitored Attenuation of Inorganic Contaminants in Ground Water Volume 2 – Assessment for Non-Radionuclides Including Arsenic, Cadmium, Chromium, Copper, Lead, Nickel, Nitrate, Perchlorate, and Selenium

Science.gov (United States)

This document represents the second volume of a set of three volumes that address the technical basis and requirements for assessing the potential applicability of MNA as part of a ground-water remedy for plumes with non-radionuclide and/or radionuclide inorganic contaminants. V...

Foodstuffs, radionuclides, monitoring

International Nuclear Information System (INIS)

Denisikov, A.I.

2000-01-01

Radionuclide contamination of water and food stuffs as a result of the Chernobyl accident and permissible contents of 90 Sr and 137 Cs are considered in brief. A method of radiation monitoring of food stuffs and water for the radionuclides mentioned is suggested. The method permits employment of the simplest and cheapest radiometric equipment for analysis, whole the high degree of radionuclide concentration using fiber sorbents permits using the instrumentation without expensive shields against external radiation. A description of ion-exchange unit for radiation monitoring of liquid samples of food stuffs or water, is provided [ru

Bioaccumulation of 137Cs by microorganisms isolated from soils contaminated with radionuclides

International Nuclear Information System (INIS)

Pipiska, M.; Hornik, M.; Augustin, J.

2003-01-01

With the aim to evaluate the possibility of utilisation of autochtone population of soil organisms, alone or with participation of higher plants, in the processes of bioremediation the authors quantitatively determined a number of psychrophyllic and mezophyllic germs in the soils contaminated by low-level activities of Cs-137 (0.08 - 2.8 kBq/g). Hereafter they gained isolates of clean cultures of mushrooms and actinomycetes and they determined their bioacumulative activity of Cs-137 at growing conditions. The authors found out, that a number of reproductionable psychrophyllic and mezophyllic germs are significantly lower in the soils with the highest contamination by radionuclides than in the soils with low contamination. They gained the clean cultures of 5 isolates of micromycetes and 3 isolates of actinomycetes from contaminated soil. The micromycetes demonstrated the highest values of bioaccumulation of caesium 39 nmol/g of wet biomass at the growing conditions. In actionoomycetes these values were 4.7 nmol/g (approximately in one order lower). The significant part of cesium accumulated by cell matter at growing conditions were localised in cell matter and it could not be removed by washing with 0.9 percent of NaCl solution. The determined values of bioconcentration factor BCF recalculated on dry weight of biomass were in the range from 16.04 to 26.20 in micromycetes and 3.24 in actinomycetes. From this situation arise, that autochtone population of soil micromycetes and actionomycetes, which is found in contaminated soil, can relevantly participate in the processes of binding of biologically accessible forms of Cs-137 after a creation of suitable conditions for grow. (author)

Oak Ridge Integrated Field-Scale Research Challenge ERKP686: Multi-scale Investigations on the Rates and Mechanisms of Targeted Immobilization and Natural Attenuation of Metal, Radionuclide and Co-Contaminants in the Subsurface (project overview)

International Nuclear Information System (INIS)

Phil Jardine; Dave Watson; Susan Hubbard; Ken Williams; J. Chen

2007-01-01

and dilution of contaminants along flow pathways and determine how they change temporally and spatially during episodic events, seasonally, and long term. (2) determine the rates and mechanisms of coupled hydrological, geochemical, and microbiological processes that control the natural attenuation of contaminants in highly diverse subsurface environments over scales ranging from molecular to watersheds. (3) explore novel strategies for enhancing the subsurface stability of immobilized metals and radionuclides. (4) understand the long-term impacts of geochemical and hydrologic heterogeneity on the remobilization of immobilized radionuclides. (5) improve our ability to predict the long-term effectiveness of remedial activities and natural attenuation processes that control subsurface contaminant behavior across a variety of scales

Water hyacinth for phytoremediation of radioactive waste simulate contaminated with cesium and cobalt radionuclides

Energy Technology Data Exchange (ETDEWEB)

Saleh, H.M., E-mail: hosamsaleh70@yahoo.com [Radioisotope Department, Nuclear Research Center, Atomic Energy Authority, Dokki 12311, Giza (Egypt)

2012-01-15

Highlights: Black-Right-Pointing-Pointer Phytoremediation of radioactive wastes containing {sup 137}Cs and {sup 60}Co radionuclides. Black-Right-Pointing-Pointer Using water hyacinth for radioactive waste treatment. Black-Right-Pointing-Pointer Bioaccumulation of radionuclides from radioactive waste streams. Black-Right-Pointing-Pointer Factors affecting bioaccumulation of {sup 137}Cs and {sup 60}Co using floating plants. - Abstract: Phytoremediation is based on the capability of plants to remove hazardous contaminants present in the environment. This study aimed to demonstrate some factors controlling the phytoremediation efficiency of live floating plant, water hyacinth (Eichhornia crassipes), towards the effluents contaminated with {sup 137}Cs and/or {sup 60}Co. Cesium has unknown vital biological role for plant while cobalt is one of the essential trace elements required for plant. The main idea of this work i.e. using undesirable species, water hyacinth, in purification of radiocontaminated aqueous solutions has been receiving much attention. The controlling factors such as radioactivity concentration, pH values, the amount of biomass and the light were studied. The uptake rate of radiocesium from the simulated waste solution is inversely proportional to the initial activity content and directly proportional to the increase in mass of plant and sunlight exposure. A spiked solution of pH Almost-Equal-To 4.9 was found to be the suitable medium for the treatment process. The uptake efficiency of {sup 137}Cs present with {sup 60}Co in mixed solution was higher than if it was present separately. On the contrary, uptake of {sup 60}Co is affected negatively by the presence of {sup 137}Cs in their mixed solution. Sunlight is the most required factor for the plant vitality and radiation resistance. The results of the present study indicated that water hyacinth may be a potential candidate plant of high concentration ratios (CR) for phytoremediation of radionuclides

Spatial datasets of radionuclide contamination in the Ukrainian Chernobyl Exclusion Zone

Science.gov (United States)

Kashparov, Valery; Levchuk, Sviatoslav; Zhurba, Marina; Protsak, Valentyn; Khomutinin, Yuri; Beresford, Nicholas A.; Chaplow, Jacqueline S.

2018-02-01

The dataset Spatial datasets of radionuclide contamination in the Ukrainian Chernobyl Exclusion Zone was developed to enable data collected between May 1986 (immediately after Chernobyl) and 2014 by the Ukrainian Institute of Agricultural Radiology (UIAR) after the Chernobyl accident to be made publicly available. The dataset includes results from comprehensive soil sampling across the Chernobyl Exclusion Zone (CEZ). Analyses include radiocaesium (134Cs and 134Cs) 90Sr, 154Eu and soil property data; plutonium isotope activity concentrations in soil (including distribution in the soil profile); analyses of hot (or fuel) particles from the CEZ (data from Poland and across Europe are also included); and results of monitoring in the Ivankov district, a region adjacent to the exclusion zone. The purpose of this paper is to describe the available data and methodology used to obtain them. The data will be valuable to those conducting studies within the CEZ in a number of ways, for instance (i) for helping to perform robust exposure estimates to wildlife, (ii) for predicting comparative activity concentrations of different key radionuclides, (iii) for providing a baseline against which future surveys in the CEZ can be compared, (iv) as a source of information on the behaviour of fuel particles (FPs), (v) for performing retrospective dose assessments and (vi) for assessing natural background dose rates in the CEZ. The CEZ has been proposed as a radioecological observatory (i.e. a radioactively contaminated site that will provide a focus for long-term, radioecological collaborative international research). Key to the future success of this concept is open access to data for the CEZ. The data presented here are a first step in this process. The data and supporting documentation are freely available from the Environmental Information Data Centre (EIDC) under the terms and conditions of the Open Government Licence: https://doi.org/10.5285/782ec845-2135-4698-8881-b38823e533bf.

Spatial datasets of radionuclide contamination in the Ukrainian Chernobyl Exclusion Zone

Directory of Open Access Journals (Sweden)

V. Kashparov

2018-02-01

Full Text Available The dataset Spatial datasets of radionuclide contamination in the Ukrainian Chernobyl Exclusion Zone was developed to enable data collected between May 1986 (immediately after Chernobyl and 2014 by the Ukrainian Institute of Agricultural Radiology (UIAR after the Chernobyl accident to be made publicly available. The dataset includes results from comprehensive soil sampling across the Chernobyl Exclusion Zone (CEZ. Analyses include radiocaesium (134Cs and 134Cs 90Sr, 154Eu and soil property data; plutonium isotope activity concentrations in soil (including distribution in the soil profile; analyses of hot (or fuel particles from the CEZ (data from Poland and across Europe are also included; and results of monitoring in the Ivankov district, a region adjacent to the exclusion zone. The purpose of this paper is to describe the available data and methodology used to obtain them. The data will be valuable to those conducting studies within the CEZ in a number of ways, for instance (i for helping to perform robust exposure estimates to wildlife, (ii for predicting comparative activity concentrations of different key radionuclides, (iii for providing a baseline against which future surveys in the CEZ can be compared, (iv as a source of information on the behaviour of fuel particles (FPs, (v for performing retrospective dose assessments and (vi for assessing natural background dose rates in the CEZ. The CEZ has been proposed as a radioecological observatory (i.e. a radioactively contaminated site that will provide a focus for long-term, radioecological collaborative international research. Key to the future success of this concept is open access to data for the CEZ. The data presented here are a first step in this process. The data and supporting documentation are freely available from the Environmental Information Data Centre (EIDC under the terms and conditions of the Open Government Licence: https://doi.org/10.5285/782ec845-2135-4698-8881-b

Transfer of radionuclides into human milk

International Nuclear Information System (INIS)

Steiner, M.; Wirth, E.

1998-01-01

Up until now the potential radiation exposure to breast-fed babies due to contaminated human milk has not been taken into account, when deriving international limit values and reference levels for radionuclides in foodstuffs, in air at monitored work places or for exposures in the medical field. It was the aim of the research project 'Transfer of radionuclides into human milk' to quantify the transfer of incorporated radionuclides into mother's milk, and develop simple models to estimate the radiation exposure of babies through the ingestion of human milk. The study focused on considerations of the radiation exposure due to the ingestion of contaminated foodstuffs by the mother, the inhalation of radionuclides at monitored work places, and the administration of radiopharmaceuticals to breast-feeding mothers. The blocking of infant thyroid glands by stable iodine in the case of accidental releases of radioiodine was considered as well. (orig.) [de

Erosion of atmospherically deposited radionuclides as affected by soil disaggregation mechanisms

International Nuclear Information System (INIS)

Claval, D.; Garcia-Sanchez, L.; Real, J.; Rouxel, R.; Mauger, S.; Sellier, L.

2004-01-01

The interactions of soil disaggregation with radionuclide erosion were studied under controlled conditions in the laboratory on samples from a loamy silty-sandy soil. The fate of 134 Cs and 85 Sr was monitored on soil aggregates and on small plots, with time resolution ranging from minutes to hours after contamination. Analytical experiments reproducing disaggregation mechanisms on aggregates showed that disaggregation controls both erosion and sorption. Compared to differential swelling, air explosion mobilized the most by producing finer particles and increasing five-fold sorption. For all the mechanisms studied, a significant part of the contamination was still unsorbed on the aggregates after an hour. Global experiments on contaminated sloping plots submitted to artificial rainfalls showed radionuclide erosion fluctuations and their origin. Wet radionuclide deposition increased short-term erosion by 50% compared to dry deposition. A developed soil crust when contaminated decreased radionuclide erosion by a factor 2 compared to other initial soil states. These erosion fluctuations were more significant for 134 Cs than 85 Sr, known to have better affinity to soil matrix. These findings confirm the role of disaggregation on radionuclide erosion. Our data support a conceptual model of radionuclide erosion at the small plot scale in two steps: (1) radionuclide non-equilibrium sorption on mobile particles, resulting from simultaneous sorption and disaggregation during wet deposition and (2) later radionuclide transport by runoff with suspended matter

Speciation analysis of radionuclides

International Nuclear Information System (INIS)

Salbu, B.

2010-01-01

Full text: Naturally occurring and artificially produced radionuclides in the environment can be present in different physico-chemical forms (i. e. radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, complexing ability etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time dependent transformation processes such as mobilization of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, however, the original distribution of radionuclides deposited in ecosystems will change over time and influence the ecosystem behaviour. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews fractionation techniques which should be utilised for radionuclide speciation purposes. (author)

Hospital management of mass radiological casualties: reassessing exposures from contaminated victims of an exploded radiological dispersal device (RDD)

International Nuclear Information System (INIS)

Ansari, Armin; Harper, Frederick Taylor; Smith, James M.

2005-01-01

One of the key issues in the aftermath of an exploded radiological dispersal device from a terrorist event is that of the contaminated victim and the concern among healthcare providers for the harmful exposures they may receive in treating patients, especially if the patient has not been thoroughly decontaminated. This is critically important in the event of mass casualties from a nuclear or radiological incident because of the essential rapidity of acute medical decisions and that those who have life- or limb-threatening injuries may have treatment unduly delayed by a decontamination process that may be unnecessary for protecting the health and safety of the patient or the healthcare provider. To estimate potential contamination of those exposed in a radiological dispersal device event, results were used from explosive aerosolization tests of surrogate radionuclides detonated with high explosives at the Sandia National Laboratories. Computer modeling was also used to assess radiation dose rates to surgical personnel treating patients with blast injuries who are contaminated with any of a variety of common radionuclides. It is demonstrated that exceptional but plausible cases may require special precautions by the healthcare provider, even while managing life-threatening injuries of a contaminated victim from a radiological dispersal device event.

Why conventional detection methods fail in identifying the existence of contamination events.

Science.gov (United States)

Liu, Shuming; Li, Ruonan; Smith, Kate; Che, Han

2016-04-15

Early warning systems are widely used to safeguard water security, but their effectiveness has raised many questions. To understand why conventional detection methods fail to identify contamination events, this study evaluates the performance of three contamination detection methods using data from a real contamination accident and two artificial datasets constructed using a widely applied contamination data construction approach. Results show that the Pearson correlation Euclidean distance (PE) based detection method performs better for real contamination incidents, while the Euclidean distance method (MED) and linear prediction filter (LPF) method are more suitable for detecting sudden spike-like variation. This analysis revealed why the conventional MED and LPF methods failed to identify existence of contamination events. The analysis also revealed that the widely used contamination data construction approach is misleading. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radionuclide fate and effects

International Nuclear Information System (INIS)

Anon.

1983-01-01

The studies reported here deal with the full range of contaminant behavior and fate, from the initial physicochemical factors that govern radionuclide availability in terrestrial and aquatic environments to studies of contaminant transport by biological means. By design, we focus more on the biologically and chemically mediated transport processes and food-chain pathways than on the purely physical forms of contaminant transport, such as transport by wind and water

Peculiarities of Japanese millet growing on radionuclide contaminated territories

International Nuclear Information System (INIS)

Sedukova, G.V.; Samusev, A.M.; Yurchenko, N.V.

2010-01-01

In the conditions of the Republic of Belarus on the lands polluted with radionuclides there were presented results of field experiments directed to study of the influence of mineral fertilizers on the yield, 137Cs and 90Sr transfer parameters, and economical viability of Indian barnyard millet or Japanese millet (Echinochloa frumentacea) growing. There were three variants of the test: control variant (without any fertilizers), variants with entering of N70P40K80 and N90P60K100 kg/ha. Research results showed that entering of N70P40K80 increased Japanese millet yield till 450-500 c/ha. Maximum productivity of green mass, minimum radionuclide transfer factors and the highest profitability were after application of entering of N70P60K100. Entering of N90K60K100 increased the green mass yield in phase of heads appearing in 80 c/ha, in milk-wax stage – in 53 c/ha. Zootechnical quality of millet green mass was defined. Parameters of 137Cs and 90Sr transition were 0,03 and 2,6-6,4 Bq/kg:kBq/m2 correspondingly. Contamination densities of sod-podzolic loamy soils were determined to assure regulatory clean millet green mass production to be used as fodder for milk stock in order to produce whole milk and raw milk for processing. Japanese millet green mass grown for cattle feeding with purpose of milk getting could be produced at density 90Sr pollution of 0,2 Ci/km2. Sod-podzolic sandy soils with density 90Sr pollution less 1,5Ci/km2 were suitable for getting processing milk

General procedure to characterize hazardous waste contaminated with radionuclides

International Nuclear Information System (INIS)

Vokal, A.; Svoboda, K.; Necasova, M.

2002-04-01

The report is structured as follows: Overview of current status of characterization of hazardous wastes contaminated with radionuclides (HWCTR) in the Czech Republic (Legislative aspects; Categorization of HWCwR; Overview of HWCwR emerging from workplaces handling ionizing radiation sources; Mixed waste management in the Czech Republic); General procedure to characterized wastes of the HWCwR type (Information needed from the waste producer; Waste analysis plan - description of waste treatment facilities, verification of wastes, selection of waste parameters followed, selection of sampling method, selection of test methods, selection of frequency of analyses; Radiation protection plan; Non-destructive methods of verification of waste - radiography/tomography, dosimetric inspection, measuring instrumentation, methods usable for the determination of volume and surface activities of materials; Non-destructive invasive methods - internal pressure measurement and gas analysis, endoscopic examination, visual inspection; Destructive methods - sampling, current equipment at Nuclear Research Institute Rez; Identification of hazardous components in waste - chemical screening of mixed wastes; Assessment of immobilization waste matrices; Assessment of packaging; Safety analyses; QA and QC). (P.A.)

The behavior of radionuclides in the soils of Rocky Flats, Colorado

Energy Technology Data Exchange (ETDEWEB)

Litaor, M I [Tel-Hai Rodman Coll., Upper Galilee (Israel); Barth, G; Zika, E M; Litus, G; Moffitt, J; Daniels, H [Colorado Univ., Civil and Environmental Engineering Dept., Boulder, CO (United States)

1998-05-01

Radionuclide contamination of soils in Rocky Flats, Colorado, resulted from leaking drums of Pu-contaminated oil stored at an outdoor area. To evaluated the mechanisms of radionuclide transport from the contaminated soils to groundwater, an advanced monitoring system was installed across a toposequence. The impact of natural rain, snowmelt, and large-scale rain simulations on the mobility and distribution of the radionuclides in soil interstitial water was studied. The distribution of radionuclides during the monitoring period from 1993 to 1995 suggested that Pu-239 + 240 and Am-241 are largely immobile in semi-arid soils. Fractionation of Pu-239 + 240 and Am-241 to different particle sizes in the soil interstitial water suggested that most of the radionuclides (83-97%) were associated with suspended particles, whereas the level of radionuclides associated with colloidal (0.45 {mu}m > X > 1 nm) and nonfilterable (< 1 nm) fractions ranged from 1.5 to 15%. (author).

Accidental releases of radionuclides: a preliminary study of the consequences of land contamination

International Nuclear Information System (INIS)

Simmonds, J.R.; Haywood, S.M.; Linsley, G.S.

1982-10-01

The long term consequences of land contamination from accidental releases of activity from thermal reactors are examined. The radiological consequences are assessed using an analysis of the exposure of individuals and the population to ground deposits of the radionuclides released. The contribution of the different nuclides in the release by their various exposure routes to the irradiation of man are calculated as a function of time after release and the most radiologically important are identified. A preliminary assessment is made of off-site economic and social consequences of accidental releases by estimating the areas of land which would be affected by the introduction of countermeasures to control individual radiation exposure due to external irradiation from ground deposits (relocation of populations), and the intake of radionuclides contained in locally produced foodstuffs (restrictions on food production). The areas where administrative controls would be necessary decline in size with time after the release; estimates are made of this time-dependent behaviour using dynamic environmental transfer models. Finally, the collective doses saved by the introduction of countermeasures are estimated using population and agricultural distribution data for a rural location in the United Kingdom. (author)

Improving global laboratory capabilities for emergency radionuclide bioassay

International Nuclear Information System (INIS)

Li, C.; Jourdain, J.; Kramer, G. H.

2012-01-01

During a radiological or nuclear emergency, first-responders and the general public may be internally contaminated with the radionuclide(s) involved. A timely radionuclide bioassay provides important information about contamination, for subsequent dose assessment and medical management. Both technical and operational gaps are discussed in this paper. As many people may need to be assessed in a short period of time, any single laboratory may find its capabilities insufficient. Laboratories from other regions or other countries may be called upon for assistance. This paper proposes a road-map to improve global capabilities in emergency radionuclide bioassay, suggesting a phased approach for establishing a global laboratory network. Existing international collaboration platforms could provide the base on which to build such a network. (authors)

Preliminary identification of contaminating α- and β-emitting radionuclides in nuclear facilities to be decommissioned through Digital Autoradiography

International Nuclear Information System (INIS)

Haudebourg, Raphael; Fichet, Pascal

2016-01-01

In previous publications, we presented how Digital Autoradiography (DA) could be of the most useful help in a preparation to decommissioning context: with this technique, a radiological mapping of the facility to dismantle can be obtained at a rate of around 2 weeks/100 m 2 . The technique is sensitive to all types of radioactivity (including α and 3 H- or 14 C-emitted β) and to both labile and fixed radioactivity. The method (radiosensitive screens exposure followed by a scanning step at the laboratory in a small-size device) neither involves nuclear material transportation, neither produces wastes, nor requires operators' presence during signal acquisition. The purpose is to accurately locate possible contamination spots, in order to relevantly perform targeted sampling and thus limit destructive analyses runs at the laboratory. In the latest developments, additional methods were implemented to analyze various nuclear samples (wastes, blocks, rubbles, pieces of furniture, drilled cores...) through this technique, to preliminary check for contamination, and to evaluate contamination location, homogeneity, and activity. These methods have proven themselves relevant and useful to build appropriate analyses and optimized decontamination protocols at the LASE (Laboratory of Analyses and Operators' Support). In this paper, we propose a new autoradiographic tool providing the identification of the contaminating radionuclide of a sample or an area, based on the stacking of several screens. The decrease of the signal screen after screen could be considered specific to one radionuclide. Modeling results obtained through Monte Carlo N-Particle transport code (MCNP) were in excellent agreement with experimental results obtained with sealed sources. Moreover, a method was developed to scan all the screens in the stack in only one run (instead of as many runs as screens) to shorten analysis duration. In the case of non-penetrating radiations (α particles, 3 H- or

A new possible biological interface model useful to narrate the artificial negative events by the radioactive contaminations and heavy-metals pollution of the soil and the atmosphere in different areas of Europe

International Nuclear Information System (INIS)

Pasquinelli, P.; Boschi, A.

2002-01-01

A lot of environmental negative effects are associated to the pollution and radioactive contaminations of the soil and the atmosphere. Actually the C.I.S.A.M. (Interforces Centre for Studies and Military Applications) receives increasing commitments to control and to knowledge about the risks of the population and soldiers employed as stabilization or keeping peace force in large areas of different territories of Europe and other sites of the Planet. The aim of this work is focused to compare the contents of radionuclides on specific natural interfaces in different areas as residual radioactive contamination in addition to the other possible heavy-metals pollution. We used barks, lichens and symbiontic microalgae as interfaces with the atmospheric events of the Chernobyl, Balkan, and the Italian areas. The qualitative analysis of these biological matters showed the constant presence of Radiocesium, along with other radionuclides, of which we report the concentrations. Even if these observations are not completely new, nevertheless we can suppose that this approach could be a new possible interface model useful to narrate the sequence of the the artificial negative events due to the human activities and contemporarely an indirect valuation of different risks pointed to the protection of the exposed population

Radionuclide contaminant analysis of small mammals at Area G, TA-54, Los Alamos National Laboratory, 1995

International Nuclear Information System (INIS)

Bennett, K.; Biggs, J.; Fresquez, P.

1997-01-01

At Los Alamos National Laboratory, small mammals were sampled at two waste burial sites (Site 1-recently disturbed and Site 2-partially disturbed) at Area G, Technical Area 54 and a control site on Frijoles Mesa (Site 4) in 1995. Our objectives were (1) to identify radionuclides that are present within surface and subsurface soils at waste burial sites, (2) to compare the amount of radionuclide uptake by small mammals at waste burial sites to a control site, and (3) to identify if the primary mode of contamination to small mammals is by surface contact or ingestion/inhalation. Three composite samples of at least rive animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. Samples were analyzed for 241 Am, 90 Sr , 238 Pu, 239 Pu, total U, 137 Cs, and 3 H. Significantly higher (parametric West at p=0.05) levels of total U, 241 Am, 238 Pu and 239 Pu were detected in pelts than in carcasses of small mammals at TA-54. Concentrations of other measured radionuclides in carcasses were nearly equal to or exceeded the mean concentrations in the pelts. Our results show higher concentrations in pelts compared to carcasses, which is similar to what has been found at waste burial/contaminated sites outside of Los Alamos National Laboratory. Site 1 had a significantly higher (alpha=0.05, P=0.0125) mean tritium concentration in carcasses than Site 2 or Site 4. In addition Site 1 also had a significantly higher (alpha=0.05, p=0.0024) mean tritium concentration in pelts than Site 2 or Site 4. Site 2 had a significantly higher (alpha=0.05, P=0.0499) mean 239 Pu concentration in carcasses than either Site 1 or Site 4

Management of industrial sites contaminated with radionuclides and stake-holders involvement

International Nuclear Information System (INIS)

Oudiz, A.; Cessac, B.; Brenot, J.; Maigne, J.P.; Santucci, P.

2001-01-01

The method to be used for the assessment and management of the radiation risks associated with sites contaminated with radionuclides was recently developed in France at the request of the authorities. The aim is to provide all the stakeholders (administrations, elected representatives, engineering companies, operators, residents' associations and environmental protection organizations) with a guide describing how to proceed. There are six stages: the removal of doubt, the pre-diagnosis, the initial diagnosis, the simplified risk study, the detailed risk study and the assistance in the selection of the remediation strategy. Each stage of risk assessment involves the stakeholders to a greater or lesser degree depending on the complexity of the site in question. The guide outlines the criteria which enable the assessment sequence to be interrupted and the appropriate decisions to be taken. For example, one can stop at the stage of the simplified risk study when the site is small and if it is relatively easy to remove and store the contaminated soil. However, in many cases a detailed risk study will be needed. The selection of the appropriate strategy presupposes the identification of several alternate strategies which must be characterized in terms of reduction of dosimetric impact, reduction of contamination, costs and associated nuisances. The choice of strategy requires the involvement of the stakeholders. The degree of involvement depends of the sites specific context. The radiological aspect is generally only one of the elements of the choice, and the conditions have to be created to enable the stakeholders to discuss all the relevant aspects in the site's specific context. (authors)

Evaluation of radionuclide migration in forest ecosystems in TEMAS project

International Nuclear Information System (INIS)

Claver, F.; Vazquez, C.

1998-01-01

The applicability study of the best countermeasures for the restoration of environments contaminated by the accidental liberation of radionuclides, requires the assessment of the space and the temporal flow of radionuclides. The objective of the multinational project TEMAS (Techniques and Management Strategies for environmental restoration and their ecological consequences), that is carried out under EU-CIEMAT contract n. TI4-CT95-0021, is the development of management tool that provides the necessary support in the selection of the best strategies of environmental restoration after a nuclear accident, considering all the possible affected environments (urban, agricultural, semi natural and forest). In the forest environment,CIEMAT is working with the University of Lund (Sweden) and the Physical Science Faculty of the University of Seville in the prognosis of the distribution of Cesium and Strontium in forest ecosystems and through the associated production systems. This paper summarizes the study of the response of two different models, FORM and FORESTPATH to predict the radionuclides flow in the event of an accidental contamination of a forest. The comparison of results has been carried out over a period of 100 years after deposition on a coniferous forest. Although the approaches are different, the results obtained (using generic parameters) indicate that either model could to be selected for the analysis of the intervention in TEMAS. (Author) 14 refs

Fire as a long-term stewardship issue for soils contaminated with radionuclides in the western U.S

International Nuclear Information System (INIS)

Shafer, David S.; DuBois, David; Etyemezian, Vic; Kavouras, Ilias; Miller, Julianne J.; Nikolich, George; Stone, Mark

2007-01-01

On both U.S. Department of Energy (DOE) and U.S. Department of Defense sites in the southwestern United States (U.S.), significant areas of surface soils are contaminated with radionuclides from atmospheric nuclear testing, and with depleted uranium, primarily from military training. At DOE sites in Nevada, the proposed regulatory closure strategy for most sites is to leave contaminants in place with administrative controls and periodic monitoring. Closure-in-place is considered an acceptable strategy because the contaminated sites exist on access-restricted facilities, decreasing the potential risk to public receptor, the high cost and feasibility of excavating contaminated soils over large areas, and the environmental impacts of excavating desert soils that recover very slowly from disturbance. The largest of the contaminated sites on the Tonopah Test Range in Nevada covers over 1,200 hectares. However, a factor that has not been fully investigated in the long-term stewardship of these sites is the potential effects of fires. Because of the long half-lives of some of the contaminants (e.g., 24,100 years for 239 Pu) and changes in land-cover and climatic factors that are increasing the frequency of fires throughout the western U.S., it should be assumed that all of these sites will eventually burn, possibly multiple times, during the time frame when they still pose a risk. Two primary factors are contributing to increased fire frequency. The first is the spread of invasive grasses, particularly cheat grass (Bromus tectorum and Bromus rubens), which have out-competed native annuals and invaded inter-spaces between shrubs, allowing fires to burn easier. The second is a sharp increase in fire frequency and size throughout the western U.S. beginning in the mid-1980's. This second factor appears to correlate with an increase in average spring and summer temperatures, which may be contributing to earlier loss of soil moisture and longer periods of dry plant biomass

Radionuclide Sensors for Water Monitoring

International Nuclear Information System (INIS)

Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

2004-01-01

Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem that requires monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to an analytical laboratory, where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90Sr, 99Tc, and various actinides of interest. The objective of this project is to investigate novel sensor concepts and materials for sensitive and selective determination of beta- and alpha-emitting radionuclide contaminants in water. To meet the requirements for loW--level, isotope-specific detection, the proposed sensors are based on radiometric detection. As a means to address the fundamental challenge of the short ranges of beta and alpha particle s in water, our overall approach is based on localization of preconcentration/separation chemistries directly on or within the active area of a radioactivity detector. Automated microfluidics is used for sample manipulation and sensor regeneration or renewal. The outcome of these investigations will be the knowledge necessary to choose appropriate chemistries for selective preconcentration of radionuclides from environmental samples, new materials that combine chemical selectivity with scintillating properties, new materials that add chemical selectivity to solid-state diode detectors, new preconcentrating column sensors, and improved instrumentation and signal processing for selective radionuclide sensors. New knowledge will provide the basis for designing effective probes and instrumentation for field and in situ measurements

RADIONUCLIDES DISTRIBUTION NEAR FORMER URANIUM MINING

Directory of Open Access Journals (Sweden)

D. A. Zaredinov

2016-01-01

Full Text Available The paper shows, that radionuclides from the stony rocks of uranium mines can be leached by atmospheric precipitations. In acid conditions, a degree of leaching is greater.Goal. The aim of this investigation was to study the distribution of radionuclides in uranium minings and their impact on the environmental contamination.Materials and methods. The study was carried out in two stages. In the first stage, a blade of rock was mixed with distilled water in proportions of 0,3 kg of gravel and 1 liter of water. After thirty days of soaking, water was sent to the gamma-spectrometric analysis to Canberra’s spectrometer (USA with a high-purity germanium detector. In the second stage, we carried out the similar experiment with water, wich was acidified to pH = 3. Contamination levels of areas near the in-situ leaching mine were determined. Intervention levels were used to estimate risk and possible water consumption by the population. Estimations were carried out taking into account the combined presence of several radionuclides in the water.Results. The results of these studies have shown that the distribution of radionuclides from the source of the contamination is about 360 meters during the 30 y period. The stream, along which samples of soil were collected and studied, was formed by the miner waters that flow along small ruts towards a village, thereby increasing the likelihood of water use by the public.Conclusions. The uranium mines are the source of radioactive contamination. Radionuclides are distributed due to the erosion of rocks and leached out of the stony rock by precipitations. The extent of leaching is significantly increased in an acidic environment, which takes place near the in-situ leaching mines.

Results for the second quarter 2014 tank 50 WAC slurry sample chemical and radionuclide contaminants

International Nuclear Information System (INIS)

Bannochie, C.

2014-01-01

This report details the chemical and radionuclide contaminant results for the characterization of the 2014 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System

Results for the Third Quarter 2014 Tank 50 WAC slurry sample: Chemical and radionuclide contaminants

Energy Technology Data Exchange (ETDEWEB)

Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-01-08

This report details the chemical and radionuclide contaminant results for the characterization of the 2014 Third Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time.¹ Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Results For The Fourth Quarter 2014 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminants

Energy Technology Data Exchange (ETDEWEB)

Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-09-30

This report details the chemical and radionuclide contaminant results for the characterization of the Calendar Year (CY) 2014 Fourth Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Results For The Second Quarter 2013 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminants

Energy Technology Data Exchange (ETDEWEB)

Bannochie, Christopher J.

2013-07-31

This report details the chemical and radionuclide contaminant results for the characterization of the 2013 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by Saltstone Facility Engineering (SFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

A Study on the Determination of Radionuclide Concentrations in Animal Feedstuffs for Use Following a Nuclear Emergency

International Nuclear Information System (INIS)

Hwang, Won Tae; Kim, Eun Han; Suh, Kyung Suk; Choi, Young Gil; Han, Moon Hee

2001-01-01

The optimized derived intervention levels for animal products were evaluated based on cost-benefit analysis. From these results, the radionuclide concentrations in animal feedstuffs for use were derived. It was shown that radionuclide concentrations in animal feedstuffs for use depend strongly on animal products, radionuclides and feeding period (period from the starting time to be fed with contaminated feedstuffs to production time of animal products). In case of feedstuffs contaminated with long-lived radionuclides ( 137 Cs, 90 Sr), the feedstuffs with lower contamination should be supplied to animals with increase of feeding period due to the bioaccumulation of radionuclides. While, in case of feedstuffs contaminated with short-lived radionuclides ( 131 I), the feeding of higher contaminated feedstuffs was possible with increase of feeding period due to radionuclide decay. It was shown that 137 Cs concentration in animal feedstuffs for use was lower than 90 Sr concentration. It is primarily due to the higher feed-animal product transfer factor of 137 Cs

Differences in the regulation of chemicals and radionuclides

International Nuclear Information System (INIS)

Travis, C.C.

1993-12-01

Government regulations limiting public exposure to radionuclides and chemicals have historically been developed by regulatory agencies using different approaches with the result that levels of protection vary for the two classes of contaminants. These differences create difficulties in determining equitable regulatory measures when both radionuclides and chemical pollutants are involved. Generally, radiation exposure is not regulated as stringently as chemical exposure (Travis et al, 1989). The International commission on Radiological Protection (ICRP) recommends limiting excess environmental radiation exposure to the general public to 100 millirem per year (mrem/yr) (ICRP, 1991), a lifetime cancer risk of about 3.5E-3. An acceptable level of risk for chemical exposures is generally considered to be below 1E-6. Differences in regulatory approach for radionuclides and chemicals evoke debate over why they are different and which regulation strategy is better. Because these pollutants often coexist (mixed waste sites, contaminated metals and facilities, etc.), it is important to analyze inconsistencies in the regulation of chemicals and radionuclides and establish a more consistent approach to defining an acceptable level of exposure for these contaminants

Dynamics of radionuclides in forest ecosystems

International Nuclear Information System (INIS)

Steiner, M.

2004-01-01

The unique physiology and the layered structure of forest ecosystems result in dynamic transport and transfer processes which greatly differ from those in agricultural ecosystems. Radionuclides are retained in the upper organic horizons of forest soil for several decades and remain highly available for uptake by fungi and green plants. Contamination levels of mushrooms and game may therefore by far exceed those of agricultural produce. The efficient cycling of nutrients and radionuclides, which is characteristic for ecosystems poor in nutrients, can largely be attributed to forest soil with its complex and multi-layered structure and fungal activity. Fungi directly affect dynamic processes, playing a key role in the mobilization, uptake and translocation of nutrients and radionuclides. Fungal fruit bodies may be highly contaminated foodstuff and fodder. They are most likely the cause of the surprising trend of increasing contamination of wild boar which has been observed in the last few years in Germany. This paper is intended to give a qualitative survey of dynamic transport processes in forests and their relevance for radiation exposure to man. (orig.)

Preparation of porous materials for radionuclides capture

International Nuclear Information System (INIS)

Bajzikova, Anna; Smrcek, Stanislav; Kozempel, Jan; Vlk, Martin; Barta, Jan

2015-01-01

Porous materials showing promise for radionuclide capture from water at contaminated sites were prepared. Nanoporous materials (size of pores 1-100 nm) and some polymers are well suited to this purpose owing their affinity for selected radionuclides. Nanoporous metal oxides and silica gel with styrene-divinylbenzene-TODGA-modified surface were prepared, characterized and tested for radionuclide ( 227 Ac, 227 Th, 223 Ra) capture efficiency. (orig.)

Long-term environmental behaviour of radionuclides

Energy Technology Data Exchange (ETDEWEB)

Brechignac, F.; Moberg, L.; Suomela, M

2000-04-01

The radioactive pollution of the environment results from the atmospheric nuclear weapons testing (during the mid-years of twentieth century), from the development of the civilian nuclear industry and from accidents such as Chernobyl. Assessing the resulting radiation that humans might receive requires a good understanding of the long-term behaviour of radionuclides in the environment. This document reports on a joint European effort to advance this understanding, 3 multinational projects have been coordinated: PEACE, EPORA and LANDSCAPE. This report proposes an overview of the results obtained and they are presented in 6 different themes: (i) redistribution in the soil-plant system, (ii) modelling, (iii) countermeasures, (iv) runoff (v) spatial variations, and (vi) dose assessment. The long term behaviour of the radionuclides {sup 137}Cs, {sup 90}Sr and {sup 239-240}Pu is studied through various approaches, these approaches range from in-situ experiments designed to exploit past contamination events to laboratory simulations. A broad scope of different ecosystems ranging from arctic and boreal regions down to mediterranean ones has been considered. (A.C.)

Long-term environmental behaviour of radionuclides

International Nuclear Information System (INIS)

Brechignac, F.; Moberg, L.; Suomela, M.

2000-04-01

The radioactive pollution of the environment results from the atmospheric nuclear weapons testing (during the mid-years of twentieth century), from the development of the civilian nuclear industry and from accidents such as Chernobyl. Assessing the resulting radiation that humans might receive requires a good understanding of the long-term behaviour of radionuclides in the environment. This document reports on a joint European effort to advance this understanding, 3 multinational projects have been coordinated: PEACE, EPORA and LANDSCAPE. This report proposes an overview of the results obtained and they are presented in 6 different themes: i) redistribution in the soil-plant system, ii) modelling, iii) countermeasures, iv) runoff v) spatial variations, and vi) dose assessment. The long term behaviour of the radionuclides 137 Cs, 90 Sr and 239-240 Pu is studied through various approaches, these approaches range from in-situ experiments designed to exploit past contamination events to laboratory simulations. A broad scope of different ecosystems ranging from arctic and boreal regions down to mediterranean ones has been considered. (A.C.)

Radionuclide Sensors for Subsurface Water Monitoring. Final report

International Nuclear Information System (INIS)

Timothy DeVol

2006-01-01

Contamination of the subsurface by radionuclides is a persistent and vexing problem for the Department of Energy. These radionuclides must be measured in field studies and monitored in the long term when they cannot be removed. However, no radionuclide sensors existed for groundwater monitoring prior to this team's research under the EMSP program. Detection of a and b decays from radionuclides in water is difficult due to their short ranges in condensed media

Fire fighting in a radionuclide laboratory

International Nuclear Information System (INIS)

Wenzel, H.

1991-01-01

A fire-brigade was called to a laboratory which held a handling licence for the radionuclides C-14, T, P-32, Se-75, Mo-99, and S-35. The fire-brigade was unaware of a release of radionuclides. Therefore they used respiratory equipment, and all persons present were subsequently examined for contamination. (DG) [de

The use of lichens as bioindicators of atmospheric contamination by natural radionuclides and metals in a region impacted by TENORM

International Nuclear Information System (INIS)

Leonardo, Lucio

2010-01-01

The main aim of this thesis is to study the possibility of using lichen as bioindicator of atmospheric pollution in regions contaminated by radionuclides, metals and rare earth elements. Two regions were chosen, one in Pirapora do Bom Jesus, where a tin and lead industry is located, and a second one in Cubatao, where a phosphate fertilizer industrial complex is located. The two industries chosen are considered as TENORM - Technologically Enhanced Naturally Occurring Radioactive Material, since they can cause a significant increase in the natural radionuclides concentration in the industrial process, and consequently a potential increase in the radiation exposure in products, byproducts and residue. To achieve this aim, the radionuclides 238 U, 226 Ra, 210 Pb, 2' 3 2 Th and 228 Ra, rare earth elements and metals were analyzed in samples of raw material and residues from the installations, lichens and soils. Lichens and soil samples were analyzed by instrumental neutron activation analysis for the determination of uranium, thorium, rare earth elements and metals. The radionuclides 226 Ra, 228 Ra and 2 '1 0 Pb in soil samples were determined by gamma spectrometry and in lichen sample by radiochemical separation and gross alpha and beta counting on a gas flow proportional counter. The concentrations of 238 U (from 19 to 473 Bq kg -1 ), 226 Ra (from 21 to 265 Bq kg -1 ), 210 Pb (from 401 to 1461 Bq kg -1 ), 232 Th (from 15 to 574 Bq kg -1 ), 228 Ra (from 176 to 535 Bq kg'- 1 ), rare earth elements, Hf and Ta determined in lichen samples around the tin and lead industry show an enrichment in these elements. Therefore, the lichens can be used as a fingerprint of the atmospheric contamination. The results obtained for the lichen samples, in the Cubatao region, present a fingerprint mainly of 210 Pb, from industries of the region. The results obtained in this study showed that the lichens can be used as bioindicators of atmospheric pollution by radionuclides and trace

Review Paper of Radionuclide Monitoring in Food Sample

International Nuclear Information System (INIS)

Noor Fadzilah Yusof; Abdul Kadir Ishak; Wo, Y.M.; Nurrul Assyikeen Mohd Jaffary

2011-01-01

The uncontrolled release of radionuclides into the atmospheric and aquatic environments may occur as the result of a nuclear or radiological accident. Monitoring of the accidental release at its source and especially direct monitoring of the environmental contamination with radionuclides is necessary for assessment and application of public protective actions and longer term countermeasures as well as emergency workers' protection. In areas historically contaminated with long lived radionuclides monitoring it is essential to protect the public and substantiation of any radiological incidents. Also, dietary pathways can be contaminated with radioactive materials resulting from natural occurrence or man-made applications especially during routine operation, accidents and migration of radionuclides from radioactive waste disposal repositories into the biosphere. Therefore, efforts should be made to determine the presence of radionuclides in a potentially high radiation area especially in operational nuclear facilities. This paper will review the strategies for food monitoring that has been adapted in most countries to obtain baseline data for future reference. Also, this study is discussing the type of food selection commonly collected as sample for radionuclide analysis in different countries over the years. Sampling procedure and analysis also included in this review for better understanding of the analysis. Stake holders' involvement is considered as an important asset in the establishment of monitoring strategies. As a conclusion, future plans for food monitoring programme in Malaysia are recommended as a preparation to embark on the Nuclear Power Plant programme. (author)

Environmental Modelling of Remediation of Urban Contaminated Areas. Report of the Urban Remediation Working Group of EMRAS Theme 2

International Nuclear Information System (INIS)

2012-01-01

The Urban Remediation Working Group of the International Atomic Energy Agency's EMRAS (Environmental Modelling for RAdiation Safety) programme was concerned with remediation assessment for urban areas contaminated with dispersed radionuclides. Types of events that could result in dispersal or deposition of radionuclides in an urban situation include both intentional and unintentional events, and releases could range from major events involving a nuclear facility to small events such as a transportation accident. The primary objective of the Urban Remediation Working Group was (1) to test and improve the prediction of dose rates and cumulative doses to humans for urban areas contaminated with dispersed radionuclides, including prediction of changes in radionuclide concentrations or dose rates as a function of location and time; (2) to identify the most important pathways for human exposure; and (3) to predict the reduction in radionuclide concentrations, dose rates, or doses expected to result from various countermeasures or remediation efforts. Specific objectives of the Working Group have included (1) the identification of realistic scenarios for a wide variety of situations, (2) comparison and testing of approaches and models for assessing the significance of a given contamination event and for guiding decisions about countermeasures or remediation measures implemented to reduce doses to humans or to clean up the contaminated area, and (3) improving the understanding of processes and situations that affect the spread of contamination to aid in the development of appropriate models and parameter values for use in assessment of these situations. The major activities of the Working Group have included three areas. The first of these was a review of the available modelling approaches and computer models for use in assessing urban contamination and potential countermeasures or remediation activities. The second area of work was a modelling exercise based on data

DIRECTIONS FOR THE RECOVERY OF AGRICULTURAL PRODUCTION ON RADIOACTIVELY CONTAMINATED LANDS

Directory of Open Access Journals (Sweden)

Kustovska O.V.

2016-05-01

friendly. The suspension of activities and the provision of radioactively clean food products led to the growth of volumes of consumption of contaminated food of local production, the increase in the number of people exceeding the doses of internal irradiation and the deterioration of the health status of the people of radioactively contaminated territories. The main component of the mechanism by contaminated land is agricultural activities (placement of crops, depending on the ability to accumulate radionuclides, soil treatment, agrochemical activities (liming of acidic soils, application of mineral and organic fertilizers and the use of sorbents, change of mode of feeding of animals and processing of animal products to reduce the content of radionuclides. Of course, the above list of events is far from complete, this is only the basic that require mandatory implementation in agricultural production. Among the measures of rehabilitation of polluted areas leading place belongs to the radical improvement of meadows and pastures, which in turn requires a considerable amount of seeds of cereals and legumes. The analysis of economic efficiency of growing of the testes, including radioactively contaminated region shows that even in marginal soils of Polesye in low yield of the seed farms have substantial profits. On soils with acidity the most common and affordable event reduce radionuclide accumulation in products is liming, which not only reduces the accumulation of radionuclides in agricultural crops but also improves soil fertility, increases yield and contributes to the dilution of radionuclides per unit mass of crop production. Only a comprehensive use of differentiated areas of contaminated land will allow some measure to improve the ecological situation on the territory of the object.

Performance study and influence of radiation emission energy and soil contamination level on γ-radiation shielding of stabilised/solidified radionuclide-polluted soils

International Nuclear Information System (INIS)

Falciglia, Pietro P.; Puccio, Valentina; Romano, Stefano; Vagliasindi, Federico G.A.

2015-01-01

This work focuses on the stabilisation/solidification (S/S) of radionuclide-polluted soils at different 232 Th levels using Portland cement alone and with barite aggregates. The potential of S/S was assessed applying a full testing protocol and calculating γ-radiation shielding (γRS) index, that included the measurement of soil radioactivity before and after the S/S as a function of the emission energy and soil contamination level. The results indicate that setting processes are strongly dependent on the contaminant concentration, and for contamination level higher than 5%, setting time values longer than 72 h. The addition of barite aggregates to the cement gout leads to a slight improvement of the S/S performance in terms of durability and contaminant leaching but reduces the mechanical resistance of the treated soils samples. Barite addition also causes an increase in the γ-rays shielding properties of the S/S treatment up to about 20%. Gamma-ray measurements show that γRS strongly depends on the energy, and that the radioactivity with the contamination level was governed by a linear trend, while, γRS index does not depend on the radionuclide concentration. Results allow the calculated γRS values and those available from other experiments to be applied to hazard radioactive soil contaminations. - Highlights: • We assess the effects of 232 Th contamination on performance of S/S treated soil. • We assess the γ-radiation shielding of the S/S materials as a function of energy. • We report a full testing protocol for assessing S/S resistance performance. • Emission energy influences the γ radiation shielding of the S/S. • Barite gives high γ-radiation shielding and low contaminant leaching

Manmade and natural radionuclides in north east Atlantic shelf and slope sediments: Implications for rates of sedimentary processes and for contaminant dispersion

International Nuclear Information System (INIS)

MacKenzie, A.B.; Stewart, A.; Cook, G.T.; Mitchell, L.; Ellet, D.J.; Griffiths, C.R.

2006-01-01

Results are presented for a study of manmade and natural radionuclides in north east Atlantic continental shelf and slope sediments to the west of Scotland. The data are interpreted in the context of sediment mixing and accumulation processes and are used to establish the westward extent of contamination of the sediment system. Offshore shelf and slope sediments were found to have post-glacial sedimentation rates of the order of 1 cm ky -1 but nearshore sediments had much higher accumulation rates of the order of 0.1 cm y -1 . Surface mixed layer depths of up to 6 cm were observed and non-local mixing affected most of the slope sediments, resulting in advective transport of surface sediment to depths of up to 10 cm. Biodiffusion coefficients for offshore shelf and slope sediments were dominantly in the range 10 -8 to 10 -9 cm 2 s -1 . The study confirmed that seawater contaminated with Sellafield waste radionuclides is dominantly entrained to the east of 7 deg. W and, consistent with this, higher levels of Sellafield derived radionuclides were confined to nearshore sediments, with lower levels to the west of 7 deg. W. 238 Pu/ 239,24 Pu data indicated that Sellafield contributed 75-91% of the total plutonium in coastal sediment but only about 4-8% of the total in slope sediments. By analogy, it can be concluded that a similar situation will apply to other contaminants in seawater entering the north east Atlantic via the North Channel

Geoinformational modelling of the land use of Polesye and Opolje landscapes in Bryansk region (Russia) under conditions of 137Cs radionuclides contamination

Science.gov (United States)

Nenko, Christina; Linnik, Vitaliy; Volkova, Nadezhda

2015-04-01

Significant part of Russian Federation was contaminated by 137Cs radionuclides due to Chernobyl disaster in 1986. South-western part of Bryansk region has suffered the most. Study area (the central part of Bryansk region, Polesye and high plains landscapes) is situated outside the officially specified zone of contamination with contamination levels under 1 Ci / km2. Nevertheless, such contamination levels (which are 20 times greater than levels of global fallout) require particular attention as it may contain a threat of the land use and the health of population, living within the territory. Radioactive contamination within the model area was formed as a result of a "dry" deposition from the atmosphere. Consequently, the initial contamination of soil by isotopes 137Cs, unlike the western part of the Bryansk region, was spread relatively equally. The main part of 137Cs (up to 90%) in natural landscapes is contained in the top 5 cm of soil, which itself creates danger of biogeochemical migration from soil to plants. In agricultural landscapes under cultivation 137Cs is uniformly spread within a 20 cm layer of soil and can also come from soil to plants grown in the fields. The area of radioactive contamination that was formed during the period of deposition (late April - early May 1986), is exposed to the processes of secondary redistribution. It is influenced by several factors as topography, vegetation type, proportion of arable soils, soil humidity, soil texture etc. In the presented study there was evaluated the impact of these factors on the secondary redistribution of 137Cs. Sustainable development of agricultural production in the contaminated territories requires managing a number of measures to reduce radiation risks to the population. Regarding this point the greatest threat may be represented by milk production, as well as picking berries and mushrooms. Planning of the sustainable use of the territory requires an evaluation of contamination levels within

Radionuclide composition in the surface layer of particles in the troposphere and stratosphere falls

International Nuclear Information System (INIS)

Prokof'ev, O.N.

1977-01-01

Radionuclide content in troposphere and stratosphere fall-outs as well as radionuclide washing-off from fall-out particle; are important to determine internal irradiation doses received by separate critical organs of human body. In surface-contaminated products (floury products of grain contaminated while in ears, vegetables, fruits, berries, noncovered or insufficiently covered products during fall-outs) radionuclides initially (in an initial state) are connected with fall-out particles. Radionuclides in biologically contaminated products (milk, meat etc.) are not connected with the particles and have the assimilable form. However, the degree of radionuclide transition from forage (grasses, hay etc.) surface-contaminated as a results of fall-outs into animal produce (milk, meat etc.) also depends on radionuclide washing-off from fall-out particles, which in the latter results from the formation nature and a kind of particles of the main substance. Radionuclide washing-off degree (and, consequently, biological availability) by glazed silicate particles is caused by radionuclide distribution between particle volume and surface in an appropriate sample. According to Israel Yu.A. method calculated were the shares of surface-bound atoms for all the particle totality in an explosion cloud for mass chains, which composition includes biologically important radionuclides. Particle solidification time is taken to equal 7 and 40s. Independent yields of chain radionuclides and its total yield are taken for 228 U fission under 14 MeV neutron effect. The calculation results are presented in the tables

Concentration and distribution patterns of naturally occurring radionuclides in sediments and flood plain soils of the catchment area of the river Elbe

International Nuclear Information System (INIS)

Barth, A.; Jurk, M.; Weiß, D.

1998-01-01

The impact of uranium mining and milling as well as that of traditional mining activities on river sediments and flood plain soils in the catchment area of the river Elbe was investigated over the years 1994 to 1995. Contamination resulting from mining activities has been identified by comparing the median values for the measured radionuclides, and by establishing the ratio between Ra-226 and Ra-228. The transport and deposition of contaminated materials as a result of high water events, and river discharge of waste water from mining and milling facilities, can be considered to be the main paths of sediment and soil contamination. Sediments and flood plain soils located in the vicinity of former uranium mining and milling sites are primarily influenced by discharges of waste water. Long distance transport and deposition at dams, barrages and on flood plains has mainly been caused by high water events. In many cases the radionuclide concentrations were higher in the subsurface layer than in the top layer of flood plain soil. Due to termination of uranium mining and milling activities, no significant contamination of newer or fresh sediments was found. Radiation exposure arising in relation to angling or walking on flood plains is low

Radionuclides in house dust

Energy Technology Data Exchange (ETDEWEB)

Fry, F A; Green, N; Dodd, N J; Hammond, D J

1985-04-01

Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate authorising Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, although radionuclides originating rom the BNFL site can be detected in house dust, this source of contamination is a negligible route of exposure for members of the public in West Cumbria. This report presents the results of the Board's study of house dust in twenty homes in Cumbria during the spring and summer of 1984. A more intensive investigation is being carried out by Imperial College. (author)

In-stream contaminant interaction and transport

International Nuclear Information System (INIS)

Whelan, G.

1983-07-01

In order to assess contaminant exposure levels in biotic and abiotic pathways from waste-disposal sites, a comprehensive Multimedia Contaminant Environmental Exposure Assessment (MCEA) methodology using several mathematical models is being developed. Prior to a full development of the proposed methodology, a scaled-down version involving terrestrial plants, overland, and in-stream compartments was applied to an actual shallow land waste-disposal site. The purpose was to evaluate and demonstrate the attributes of the methodology. The in-stream component of the abbreviated methodology as it relates to Mortandad Canyon in Los Alamos, New Mexico is discussed herein. A two-year period was simulated consisting of six major runoff events which possessed a variety of distributions and magnitudes. The in-stream component of the methodology was composed of two models integrated to simulate the migration of radionuclides: DKWAV and TODAM. DKWAV is an unsteady, one-dimensional, second-order, explicit, finite difference, channel flow code which simulates the hydrodynamics in dendritric river systems and includes point and/or continuous lateral inflow and channel seepage. TODAM is an unsteady, one-dimensional, finite element, sediment-contaminant transport code which simulates the migration and fate of sediment and radionuclides in their dissolved and particulate phases by solving the general advection/diffusion equation with sink and source terms

The biotic factors role in radionuclide migration of natural-vegetable complexes

International Nuclear Information System (INIS)

Yakushev, B.I.; Kazej, A.I.; Sak, M.M.; Kuz'mich, O.T.; Golushko, R.M.

1992-01-01

In Byelorussiyn from first months after the Chernobyl' accident investigation are conducting on the radionuclide de dynamics in the soil-plant-soil system. The isotope composition of soil contamination density and specific plants radioactivity are studying, the radionuclide migration dynamic through the soil profile is investigating. The data are shown on considerable reduction of the plants radioactivity (1986-91 years) in connection with the reduction in the soil contamination density with gamma-spectrum radionuclides, accounting for Ce-144, Pr-144, Ru-106, Cs-134 decay; information is done on gamma-spectrum radionuclides of organs in natural pine and meadows system. It is shown, that the radionuclides are actively absorbed by roots in a zone of the highest radionuclide concentration and are delivered into the overground plant parts, then actively are removed into environment in the breathing process. 11 refs.; 4 tabs

The possible ways for soil complex purification from radionuclides in conditions of large-scale contamination and effectiveness of used methods

International Nuclear Information System (INIS)

Bondar, Y.; Konoplia, E.

1999-01-01

There has been a considerable aggregate effect of natural factors on soils contaminated with radioactive pollution by autopurification. Such factors such as natural decay, vertical migration of nuclides over the soil profile, as well as cyclic carrying of nuclides from the soil by vegetation, have been analyzed. The contaminated Belarus Polessie soils, as the result of the Chernobyl Catastrophe, have shown that during the past 13 years, a 1.5-1.7 fold decrease of long living radionuclides has taken place in the rooting layer. The qualitative characteristics of the soil purification process by phytocoenosis have been established, and the effectiveness and limitations of this method have been demonstrated. The effect of microbiological soil processes on the radionuclides mobility have been studied and the issues of the migration process intensification by means of optimal nutrient media have been considered. Hydroseparation of highly dispersed soil particles with simultaneous consideration of the soil organic substance contents allows attainment of a purification coefficient of 1.5-2. Further increase of C pur leads to irreversible humus substance loss and depriving the soil of its fertility, in addition the quantity of solid wastes dramatically increases that should be localized. A soil cut has been carried out on an experimental plot. It has been shown that the effectiveness of this method is high in comparison with other appropriate methods. However, with time, the purification rate decreases due to the radionuclides exceeding the bounds of the cutting layer caused by migration. (author)

Cancer incidence in an area contaminated with radionuclides near a nuclear installation

International Nuclear Information System (INIS)

Johnson, C.J.

1981-01-01

Exposures of a large population in the Denver area to plutonium and other radionuclides in the exhaust plumes from the Rocky Flats (nuclear weapons) plant date back to 1953. Anglo cancer incidence in 1969-1971 was evaluated in census tracts with and without contamination in the Denver area (1970 pop. 1 019 130). Cancer incidence in males was 24% higher, and in females, 10% higher in the suburban area(pop. 154 170) with most contamination nearest the plant, compared to the unexposed area (pop. 423 870), also predominantly suburban, which had virtually the same age-adjusted incidence rate for all cancer as the state. Excess cases of cancer were due to more cases than expected of leukemia, lymphoma and myeloma and cancer of the lung, thyroid, breast, esophagus, stomach and colon, a pattern similar to that obs- erved in the survivors of Hiroshima and Nagasaki. The ratio of these cancers to all other cancer was 17.6% higher in males and 11.9% higher in females in the area near the plant. Cancer of the gonads (especially the testes), liver, and, in females, pancreas and brain contributed to the higher incidence of all cancer in areas near the plant. (Auth.)

RAGBEEF: a FORTRAN IV implementation of a time-dependent model for radionuclide contamination of beef

Energy Technology Data Exchange (ETDEWEB)

Pleasant, J C; McDowell-Boyer, L M; Killough, G G

1982-06-01

RAGBEEF is a FORTRAN IV program that calculates radionuclide concentrations in beef as a result of ingestion of contaminated feeds, pasture, and pasture soil by beef cattle. The model implemented by RAGBEEF is dynamic in nature, allowing the user to consider age- and season-dependent aspects of beef cattle management in estimating concentrations in beef. It serves as an auxiliary code to RAGTIME, previously documented by the authors, which calculates radionuclide concentrations in agricultural crops in a dynamic manner, but evaluates concentrations in beef for steady-state conditions only. The time-dependent concentrations in feeds, pasture, and pasture soil generated by RAGTIME are used as input to the RAGBEEF code. RAGBEEF, as presently implemented, calculates radionuclide concentrations in the muscle of age-based cohorts in a beef cattle herd. Concentrations in the milk of lactating cows are also calculated, but are assumed age-dependent as in RAGTIME. Radionuclide concentrations in beef and milk are described in RAGBEEF by a system of ordinary linear differential equations in which the transfer rate of radioactivity between compartments is proportional to the inventory of radioactivity in the source compartment. This system is solved by use of the GEAR package for solution of systems of ordinary differential equations. The accuracy of this solution is monitored at various check points by comparison with explicit solutions of Bateman-type equations. This report describes the age- and season-dependent considerations making up the RAGBEEF model, as well as presenting the equations which describe the model and a documentation of the associated computer code. Listings of the RAGBEEF and updated RAGTIME codes are provided in appendices, as are the results of a sample run of RAGBEEF and a description of recent modifications to RAGTIME.

RAGBEEF: a FORTRAN IV implementation of a time-dependent model for radionuclide contamination of beef

International Nuclear Information System (INIS)

Pleasant, J.C.; McDowell-Boyer, L.M; Killough, G.G.

1982-06-01

RAGBEEF is a FORTRAN IV program that calculates radionuclide concentrations in beef as a result of ingestion of contaminated feeds, pasture, and pasture soil by beef cattle. The model implemented by RAGBEEF is dynamic in nature, allowing the user to consider age- and season-dependent aspects of beef cattle management in estimating concentrations in beef. It serves as an auxiliary code to RAGTIME, previously documented by the authors, which calculates radionuclide concentrations in agricultural crops in a dynamic manner, but evaluates concentrations in beef for steady-state conditions only. The time-dependent concentrations in feeds, pasture, and pasture soil generated by RAGTIME are used as input to the RAGBEEF code. RAGBEEF, as presently implemented, calculates radionuclide concentrations in the muscle of age-based cohorts in a beef cattle herd. Concentrations in the milk of lactating cows are also calculated, but are assumed age-dependent as in RAGTIME. Radionuclide concentrations in beef and milk are described in RAGBEEF by a system of ordinary linear differential equations in which the transfer rate of radioactivity between compartments is proportional to the inventory of radioactivity in the source compartment. This system is solved by use of the GEAR package for solution of systems of ordinary differential equations. The accuracy of this solution is monitored at various check points by comparison with explicit solutions of Bateman-type equations. This report describes the age- and season-dependent considerations making up the RAGBEEF model, as well as presenting the equations which describe the model and a documentation of the associated computer code. Listings of the RAGBEEF and updated RAGTIME codes are provided in appendices, as are the results of a sample run of RAGBEEF and a description of recent modifications to RAGTIME

Residual radioactive contamination from decommissioning: Technical basis for translating contamination levels to annual dose

International Nuclear Information System (INIS)

Kennedy, W.E. Jr.; Peloquin, R.A.

1990-01-01

This document describes the generic modeling of the total effective dose equivalent (TEDE) to an individual in a population from a unit concentration of residual radioactive contamination. Radioactive contamination inside buildings and soil contamination are considered. Unit concentration TEDE factors by radionuclide, exposure pathway, and exposure scenario are calculated. Reference radiation exposure scenarios are used to derive unit concentration TEDE factors for about 200 individual radionuclides and parent-daughter mixtures. For buildings, these unit concentration factors list the annual TEDE for volume and surface contamination situations. For soil, annual TEDE factors are presented for unit concentrations of radionuclides in soil during residential use of contaminated land and the TEDE per unit total inventory for potential use of drinking water from a ground-water source. Because of the generic treatment of potentially complex ground-water systems, the annual TEDE factors for drinking water for a given inventory may only indicate when additional site data or modeling sophistication are warranted. Descriptions are provided of the models, exposure pathways, exposure scenarios, parameter values, and assumptions used. An analysis of the potential annual TEDE resulting from reference mixtures of residual radionuclides is provided to demonstrate application of the TEDE factors. 62 refs., 5 figs., 66 tabs

Manual of bioassay procedures for radionuclides

International Nuclear Information System (INIS)

Pleskach, S.; Petkau, A.

1986-06-01

A monitoring program is described by which atomic radiation workers ar monitored for internal contamination with radionuclides in the workplace. The program involves analytical procedures for measuring alpha, beta and gamma activity in biological specimens, usually urine. Radionuclides are identified by their characteristic radiation using liquid scintillation counting, and alpha, beta and gamma spectrometry. Examples of calculating the minimum detectable activity for specific radionuclides are given and used to derive call-in-criteria in accordance with which the different groups of workers are monitored each month

Contamination monitoring: an overview and its objectives

International Nuclear Information System (INIS)

Mangena, S.

2013-04-01

The study presents and objectively summarises the aspect of contamination monitoring. This envisages reviewing sources of contamination and evaluating the scientific basis for practice specific courses of action for rehabilitation in a bid to restore pristine conditions wherever possible. The practices considered include nuclear medicine, reprocessing plants, fuel production plants, uranium and thorium mining and milling together with near surface disposal facilities (for radioactive waste). It also deals with monitoring sites contaminated as a consequence of past practices. General issues related to the design and operation of monitoring systems during and in the aftermath of a nuclear or radiological accident are also discussed including monitoring for long lived radionuclides widely dispersed in the environment following an accidental release. Thus the above discourse provides a framework for both quantitative and qualitative measures undertaken to enable effective response in the event of radioactive contamination. (au)

Radioactive contamination of the biosphere and consequences for food supply

International Nuclear Information System (INIS)

Wiechen, A.

1989-01-01

The paper deals with all aspects of radioactive contamination of the biosphere and corresponding consequences for food supply. In particular, releases of radioactivity by nuclear weapon tests in the early 60's and nuclear accidents in recent years are discussed. Contamination of food in the Federal Republic of Germany by these events and corresponding ingestion dose are demonstrated using examples. Furthermore diffusion of radionuclides and their transfer through the food chains to man are described. Suitable methods of decontamination at different production steps and their viability are discussed. (orig.) [de

Absorption of radionuclide through wounded skin

International Nuclear Information System (INIS)

Kusama, Tomoko; Ogaki, Kazushi; Yoshizawa, Yasuo

1982-01-01

The translocation and absorption of 58 Co(CoCl 2 ) through a wound was investigated experimentally with mice. Physical and chemical skin damages became the objects of the investigation. Abrasion, puncture and incision were made for types of the physical damage. The chemical damage included both acid and alkaline burns. The absorptions of the radionuclide through the contaminated wounds were measured with both a 2 inches NaI(Tl) scintillation detector and an auto well gamma counter at 15,30 and 60 min after the contamination. The radionuclide was hardly absorbed through an undamaged skin. After 30 min, 20 to 40% of the radionuclide applied on the physically damaged skin was absorbed, but was not absorbed through the chemically damaged skin. The absorption rate through the physically damaged skin reached a maximum at 15 to 60 min after the contamination. The velocity of the absorption through the physically damaged skin was 100 times as much as the chemically damaged skin. The absorption rates through the physically and the chemically damaged skins were expressed by the following formulas: A=a(1-e sup(-bt)) and A=a(e sup(bt)-1), where a and b is constant, respectively. (author)

Direct contamination - seasonality

International Nuclear Information System (INIS)

Aarkrog, A.

1994-01-01

Direct contamination is the primary pathway to terrestrial vegetation in the first period after an activity release to the atmosphere. All radionuclides are able to be transferred via this pathway. Deposition, interception and retention are the three processes involved in direct contamination of crops. Wet deposition is more important than dry deposition in temperature regions. Resuspension and rainsplash both belong to secondary direct deposition and became evident for e.g. radiocaesium after the Chernobyl accident. Seasonality is the varying response to radioactive contamination of crops according to the time of the year when the contamination occurs. Shortlived radionuclides (as 131 I) and those that mainly enter the foodchain by direct contamination (e.g. 137 Cs) are especially important in this connection. In particular, the contamination of cereal crops is influenced by seasonality. As a result of seasonality the impact of the Chernobyl accident on the radioactive contamination of human diet was for the same deposition density higher in southern than in northern Europe. (orig.)

Chernobyl accident. The ground deposition of radionuclides in Padana plain and in Alps Valleys and the radioactive contamination of the Como lake

Energy Technology Data Exchange (ETDEWEB)

Capra, D; Facchini, U; Gianelle, V; Ravasini, G; Ravera, O; Volta, L; Pizzola, A; Bacci, P

1988-01-01

The radioactive cloud released during the Chernobyl accident reached the Padana plain and Lombardy in the night of April 30th 1986; the cloud remained in the northern Italian skies for a few days and then disappeared either dispersed by winds and washed by rains. The evidence in atmosphere of radionuclides as Tellurium, Iodine, Cesium, was promptly observed. The intense rain, in first week of may, washed the radioactivity and fall-out contamined the land, soil, grass. The present work concerns the overall contamination of the Northern Italy territory and in particular the radioactive fall-out in the Lakes region. Samples of soil have been measured at the gamma spectroscope; a correlation is found between the radionuclides concentration in soil samples and the rain intensity, when appropriate deposition models are considered. A number of measurements has been done on the Como'lake ecosystem: sediments, plankton, fishes and the overall fall-out in the area has been investigated.

Restoration strategies for radioactive contaminated ecosystems (RESTORE). Mastering events of the past - Nuclear fission safety programme E.2: restoration of severely contaminated territories. Final report 1996 - 1999

International Nuclear Information System (INIS)

Voigt, G.; Semioschkina, N.

2000-01-01

The RESTORE project has focused on the development of an environmental decision support system (EDSS) applied to areas of the NIS contaminated by radioactive fallout based upon an understanding of such processes. It incorporates spatial variation in radioecological processes which can influence transfer of radionuclides via foodstuffs to man including soil type, ecosystem, food production systems and flooding, such factors are not considered in existing models. Special emphasis has been placed on the identification of key pathways using the knowledge incorporated into the EDSS and developing strategies whereby the dose via these pathways could be effectively reduced, in particular by enabling the population to understand and influence their own exposure. The main objectives of the project were: Identification of major pathways of radiation exposure, resulting from the Chernobyl accident, within different contaminated ecosystems within the NIS; Collation of spatial data to allow, using geographical information systems (GIS), the identification of areas with high radionuclide concentrations in foodstuffs, high fluxes of radionuclides or elevated doses; Development of practical and cost effective countermeasure strategies, targeted at key pathways, which will enable affected populations to understand and influence their own radiation exposures; Assessment of the potential importance of flooding for the redistribution and remobilization of radionuclides into food production systems; Application of this knowledge to develop an environmental decision support system (EDSS) providing a tool to identify vulnerable areas or groups and allow assessment of countermeasure strategies; Independently assess the radiological situation following nuclear weapons tests within the semipalatinsk test site (STS), Kazakhstan which was the most important nuclear weapons testing area within the USSR. (orig.)

Phytoremediation of radionuclides: an emerging alternative

International Nuclear Information System (INIS)

Singh, Shraddha

2013-01-01

Proliferation of nuclear power industry, nuclear weapon testing, dismantling of existing nuclear weapons and occasional accidents have contributed to an enhancement in the level of radionuclides in the environment. The radionuclides due to their long half life and transfer through the food chain effect adversely to normal biological systems. Hence, it is essential to effectively remove the radionuclides from contaminated soils and solutions. Phytoremediation - the use of plants for remediation of toxic metals and radionuclides has been recognized as an aesthetically pleasing, low cost and environment friendly in situ method. Phytoremediation is an umbrella term which covers several plant based approaches. Plants have shown the potential of remediation of these radionuclides from spiked solutions, low level nuclear waste and soil. Various aspects of phytoremediation as well as potential of various plants for remediation of radionuclides will be discussed here. (author)

The applicability of lichens as retrospective biomonitors of the radioactive contamination in a mountain ecosystem

International Nuclear Information System (INIS)

Gastberger, M.; Hofmann, W.; Tuerk, R.

1996-01-01

A number of previous studies have demonstrated that lichens are suitable and inexpensive biological detectors of the local fallout pattern. Lichens are usually highly contaminated and their contamination correlates well with the soil deposition data. One of their major advantages is that samples can easily be collected from quite large areas, thereby getting an average contamination of this area. Especially in mountain ecosystems, lichens could gain great importance as biomonitors, because many lichens grow in this area and, moreover, the collection of soil samples may be very difficult in these elevated regions. On the other hand, particularly in mountainous regions, the deposited radionuclide activities may vary considerably from site to site due to specific local meteorological conditions, which may also affect the growth of lichens and their uptake of radionuclides. Thus the goal of this study was to find out, whether lichens are still suitable biological detectors of the local radioactive contamination pattern several years after the initial deposition event

The development of the American National Standard 'control of radioactive surface contamination on materials equipment and facilities to be released for uncontrolled use'

International Nuclear Information System (INIS)

Shapiro, J.

1980-01-01

A new standard submitted by the Health Physics Society Standards Committee to the American National Standards Institute concerning radioactive surface contamination of materials and equipment is discussed. The chronological events in the development of this standard are given. The standard provides criteria for the release for uncontrolled use of materials, equipment and facilities contaminated or potentially contaminated with radioactivity. Permissible contamination limits are specified for: 1) long lived alpha emitters except natural uranium and thorium, 2) more hazardous beta-gamma emitters, 3) less hazardous beta-gamma emitters and 4) natural uranium and thorium. A contamination reference level of 1000 dpm/100 cm 2 for 90 Sr was set as the basis for assigning limits to radionuclides presenting an ingestion hazard and other radionuclides were grouped based on the values of their maximum permissible concentration (MPC) in water relative to 90 Sr. The contamination limit for 239 Pu was chosen as the basis for assigning limits based on MPC in air to radionuclides presenting an inhalation hazard; a value of 100 dpm/100 cm 2 was adopted in the standard. An upper limit of 5000 dpm/100 cm 2 for surface contamination was selected for the standard. (UK)

Influence of orthopedic reinforced gloves versus double standard gloves on contamination events during small animal orthopedic surgery.

Science.gov (United States)

Hayes, Galina; Singh, Ameet; Gibson, Tom; Moens, Noel; Oblak, Michelle; Ogilvie, Adam; Reynolds, Debbie

2017-10-01

To determine the influence of orthopedic reinforced gloves on contamination events during small animal orthopedic surgery. Prospective randomized controlled trial SAMPLE POPULATION: Two hundred and thirty-seven pairs of orthopedic gloves (474 gloves) and 203 pairs of double standard gloves (812 gloves) worn during 193 orthopedic procedures. Primary and assistant surgeons were randomized to wear either orthopedic reinforced gloves or double gloves. Gloves were leak tested to identify perforations at the end of procedures. Perforations detected intraoperatively or postoperatively were recorded. A contamination event was defined as at least one perforation on either hand for orthopedic reinforced gloves, or a perforation of both the inner and outer glove on the same hand for double gloves. Baseline characteristics between the 2 intervention groups were similar. There was no difference in contamination events between the double-gloved and orthopedic gloved groups (OR = 0.95, 95% CI = 0.49-1.87, P = .89). The same percentage of contamination events (8% glove pairs used) occurred in the double gloved group (17 contamination events) and in the orthopedic gloved group (19 contamination events). The odds of a contamination event increased by 1.02 (95% CI 1.01-1.03, P contamination events in small animal orthopedic procedures. Surgeons reluctant to double glove due to perceptions of decreased dexterity and discomfort may safely opt for wearing orthopedic gloves, which may improve their compliance. © 2017 The American College of Veterinary Surgeons.

Contamination of soil and food with radionuclides from Chernobyl

International Nuclear Information System (INIS)

Bikit, I.; Slivka, J.; Veskovic, M.; Conkic, Lj.; Krmar, M.

2004-01-01

The results of systematic gamma spectroscopic analyses of fission products performed on the territory of SAP Vojvodina after the Chernobyl accident are presented. Samples of soil grass and food were periodically taken at 5 representative locations and the regions of highest activity concentration are identified on the basis of the results obtained. In the controlled chain soil-plants (feeds)-cow's (milk) on three characteristic locations (soil with different physico-chemical and mechanical properties) the activity concentration of fission radionuclides was determined and transfer factors for soil-plants; feed-milk were calculated. At the territory of hunting sites of SAP Vojvodina, artificial radionuclides were determined in meat and bones of fallow-deer, deer, boar and wild hare; and the highest content of radionuclides was found in meat and bones of boar. (author)

Mechanisms of radionuclide transition in natural environment

International Nuclear Information System (INIS)

Pacyna, J.

1974-01-01

Mechanisms of radionuclide transition in various elements of the environment have been dealt with in an ecological aspect. The knowledge of the radionuclide propagation tracks will make possible to ascertain precisely causes and effects of the radiation and to reduce the contamination value. Particular attention has been paid to test methods. (author)

Migration of radionuclides in geologic media: Fundamental research needs

International Nuclear Information System (INIS)

Reed, D.T.; Zachara, J.M.; Wildung, R.E.; Wobber, F.J.

1990-01-01

An assessment of the fundamental research needs in understanding and predicting the migration of radionuclides in the subsurface is provided. Emphasis is on the following three technical areas: (1) aqueous speciation of radionuclides, (2) the interaction of radionuclides with substrates, and (3) intermediate-scale interaction studies. This research relates to important issues associated with environmental restoration and remediation of DOE sites contaminated with mixed radionuclide-organic wastes. 64 refs., 1 fig., 1 tab

Artificial radionuclides in the atmosphere over Lithuania

International Nuclear Information System (INIS)

Lujaniene, G.; Sapolaite, J.; Remeikis, V.; Lujanas, V.; Aninkevicius, V.

2006-01-01

Systematic observations of radionuclide composition and concentration in the atmosphere have been carried out at the Institute of Physics in Vilnius since 1963. An increase in activity concentration of radionuclides in the atmosphere was observed after nuclear weapon tests and the Chernobyl NPP accident. At present the radiation situation in Lithuania is determined by two main sources of radionuclides, forest fire and resuspension products transferred from highly polluted region of the Ukraine and Belarus. During forest fires the increase in activity concentration of 1 37Cs in the atmosphere was registered in many countries and in Lithuania as well. This work summarizes the experimental data on transport of cesium, plutonium, americium from the highly contaminated territories after the Chernobyl accident. The activity concentrations of 1 37Cs were measured in two - three days samples while plutonium and americium in monthly samples. In addition, the analyses of the events of the increase activity concentration, meteorological situation, speciation of radionuclides and mechanisms of formation and transformation of aerosol carriers of radionuclides are presented. Aerosols were sampled on perchlorvinyl filters and the large volume air samplers with a flow rate from 2400 m 3 /h to about 6000 m 3 /h were used. The radiochemical analyses of monthly samples of aerosol ashes (about 30 g) were performed. For separation of Pu isotopes the TOPO/cyclohexane extraction and radiochemical purification using UTEVA resin were performed, Am was separated after TOPO/cyclohexane extraction using TRU and TEVA resins (100-150 μm). 2 42Pu and 2 43Am were used as tracers in the separation procedure. The alpha spectrometry measurements of Pu and Am isotopes deposited on a stainless steel disc were carried out with the Alphaquattro (Silena) spectrometer. 1 37Cs was determined by gamma-ray spectrometry using the high purity HPGe detector (resolution - 1.9 keV/1.33 Mev, efficiency - 42

Mobilization of radionuclides from sediments. Potential sources to Arctic waters

International Nuclear Information System (INIS)

Oughton, D.H.; Boerretzen, P.; Mathisen, B.; Salbu, B.; Tronstad, E.

1995-01-01

Contaminated soils and sediments can act as secondary sources of radionuclides to Arctic waters. In cases where the original source of contamination has ceased or been greatly reduced (e.g., weapons' testing, waste discharges from Mayak and Sellafield) remobilization of radionuclides from preciously contaminated sediments increases in importance. With respect to Arctic waters, potential secondary sources include sediments contaminated by weapons' testing, by discharges from nuclear installations to seawater, e.g., the Irish Sea, or by leakages from dumped waste containers. The major land-based source is run-off from soils and transport from sediments in the catchment areas of the Ob and Yenisey rivers, including those contaminated by Mayak discharges. Remobilization of radionuclides is often described as a secondary source of contamination. Whereas primary sources of man-made radionuclides tend to be point sources, secondary sources are usually more diffuse. Experiments were carried out on marine (Kara Sea, Irish Sea, Stepovogo and Abrosimov Fjords), estuarine (Ob-Yenisey) and dirty ice sediments. Total 137 Cs and 90 Sr concentrations were determined using standard radiochemical techniques. Tracer studies using 134 Cs and 85 Sr were used to investigate the kinetics of radionuclide adsorption and desorption. It is concluded that 90 Sr is much less strongly bound to marine sediments than 137 Cs, and can be chemically mobilized through ion exchange with elements is seawater. Radiocaesium is strongly and rapidly fixed to sediments. Discharges of 137 Cs to surface sediments (i.e., from dumped containers) would be expected to be retained in sediments to a greater extent than discharges to sea-waters. Physical mobilization of sediments, for example resuspension, may be of more importance for transport of 137 Cs than for 90 Sr. 7 refs., 4 figs

Fukushima Daiichi-Derived Radionuclides in the Ocean: Transport, Fate, and Impacts.

Science.gov (United States)

Buesseler, Ken; Dai, Minhan; Aoyama, Michio; Benitez-Nelson, Claudia; Charmasson, Sabine; Higley, Kathryn; Maderich, Vladimir; Masqué, Pere; Morris, Paul J; Oughton, Deborah; Smith, John N

2017-01-03

The events that followed the Tohoku earthquake and tsunami on March 11, 2011, included the loss of power and overheating at the Fukushima Daiichi nuclear power plants, which led to extensive releases of radioactive gases, volatiles, and liquids, particularly to the coastal ocean. The fate of these radionuclides depends in large part on their oceanic geochemistry, physical processes, and biological uptake. Whereas radioactivity on land can be resampled and its distribution mapped, releases to the marine environment are harder to characterize owing to variability in ocean currents and the general challenges of sampling at sea. Five years later, it is appropriate to review what happened in terms of the sources, transport, and fate of these radionuclides in the ocean. In addition to the oceanic behavior of these contaminants, this review considers the potential health effects and societal impacts.

Unintentional drinking-water contamination events of unknown origin: surrogate for terrorism preparedness.

Science.gov (United States)

Winston, Gary; Leventhal, Alex

2008-01-01

Drinking-water is a direct conduit to many human receptors. An intentional attack (e.g. terrorism) on drinking-water systems can shock and disrupt elements of national infrastructures. We report on an unintentional drinking-water contamination event that occurred in Tel Aviv, Israel in July, 2001. Initially of unknown origin, this event involved risk management strategies used by the Ministry of Health for abating a potential public health crisis as might be envisaged of water contamination due to terrorism. In an abrupt event of unknown origin, public health officials need to be responsible for the same level of preparedness and risk communication. This is emphasized by comparison of management strategies between the Tel Aviv event and one of dire consequences that occurred in Camelford, England in 1988. From the onset of the Tel Aviv incident, the public health strategy was to employ the precautionary principle by warning residents of the affected region to not drink tap water, even if boiled. This strategy was in contrast to an earlier crisis that occurred in Camelford, England in 1988. An outcome of this event was heightened awareness that a water crisis can occur in peacetime and not only in association with terrorism. No matter how minor the contamination event or short-term the disruption of delivery of safe drinking-water, psychological, medical and public health impact could be significant.

Natural attenuation of metals and radionuclides: Report from a workshop held by Sandia National Laboratories

International Nuclear Information System (INIS)

Brady, P.V.; Borns, D.J.

1997-11-01

Natural attenuation is increasingly applied to remediate contaminated soils and ground waters. Roughly 25% of Superfund groundwater remedies in 1995 involved some type of monitored natural attenuation, compared to almost none 5 years ago. Remediation by natural attenuation (RNA) requires clear evidence that contaminant levels are decreasing sufficiently over time, a defensible explanation of the attenuation mechanism, long-term monitoring, and a contingency plan at the very least. Although the primary focus of implementation has to date been the biodegradation of organic contaminants, there is a wealth of scientific evidence that natural processes reduce the bioavailability of contaminant metals and radionuclides. Natural attenuation of metals and radionuclides is likely to revolve around sorption, solubility, biologic uptake and dilution controls over contaminant availability. Some of these processes can be applied to actively remediate sites. Others, such as phytoremediation, are likely to be ineffective. RNA of metals and radionuclides is likely to require specialized site characterization to construct contaminant and site-specific conceptual models of contaminant behavior. Ideally, conceptual models should be refined such that contaminant attenuation can be confidently predicted into the future. The technical approach to RNA of metals and radionuclides is explored here

Natural attenuation of metals and radionuclides: Report from a workshop held by Sandia National Laboratories

Energy Technology Data Exchange (ETDEWEB)

Brady, P.V.; Borns, D.J. [Sandia National Labs., Albuquerque, NM (United States). Geochemistry Dept.

1997-11-01

Natural attenuation is increasingly applied to remediate contaminated soils and ground waters. Roughly 25% of Superfund groundwater remedies in 1995 involved some type of monitored natural attenuation, compared to almost none 5 years ago. Remediation by natural attenuation (RNA) requires clear evidence that contaminant levels are decreasing sufficiently over time, a defensible explanation of the attenuation mechanism, long-term monitoring, and a contingency plan at the very least. Although the primary focus of implementation has to date been the biodegradation of organic contaminants, there is a wealth of scientific evidence that natural processes reduce the bioavailability of contaminant metals and radionuclides. Natural attenuation of metals and radionuclides is likely to revolve around sorption, solubility, biologic uptake and dilution controls over contaminant availability. Some of these processes can be applied to actively remediate sites. Others, such as phytoremediation, are likely to be ineffective. RNA of metals and radionuclides is likely to require specialized site characterization to construct contaminant and site-specific conceptual models of contaminant behavior. Ideally, conceptual models should be refined such that contaminant attenuation can be confidently predicted into the future. The technical approach to RNA of metals and radionuclides is explored here.

The radionuclide migration model in river system

International Nuclear Information System (INIS)

Zhukova, O.M.; Shiryaeva, N.M.; Myshkina, M.K.; Shagalova, Eh.D.; Denisova, V.V.; Skurat, V.V.

2001-01-01

It was propose the model of radionuclide migration in river system based on principle of the compartmental model at hydraulically stationary and chemically equilibrium conditions of interaction of radionuclides in system water-dredge, water-sediments. Different conditions of radioactive contamination entry in river system were considered. The model was verified on the data of radiation monitoring of Iput' river

Implementation of the NCRP wound model for interpretation of bioassay data for intake of radionuclides through contaminated wounds

International Nuclear Information System (INIS)

Ishigure, Nobuhito

2009-01-01

Emergency response preparedness for radiological accidents involving wound contamination has become more important, considering the current extending tendency in the nuclear industry related to the nuclear fuel cycle. The US National Council on Radiation Protection and Measurements (NCRP) proposed a biokinetic and dosimetric model for the intake of radionuclides through contaminated wounds in 2007. The present paper describes the implementation of this NCRP wound model for the prediction of systemic behaviour of some important radioactive elements encountered in workplaces related to the nuclear industry. The NCRP wound model was linked to the current ICRP systemic model at each blood compartment and simultaneous differential equations for the content of radioactivity in each compartment and excreta were solved with the Runge-Kutta method. The results of the calculation of wound, whole-body or specific organ retention and daily urinary or faecal excretion rate of some selected elements will be useful for the interpretation of bioassay data and dose assessment for cases of wound contamination. (author)

Proposed training program for construction personnel involved in remedial action work at sites contaminated by naturally occurring radionuclides

International Nuclear Information System (INIS)

Berven, B.A.; Goldsmith, W.A.; Haywood, F.F.; Schiager, K.J.

1979-01-01

Many sites used during the early days of the US atomic energy program are contaminated with radionuclides of the primordial decay chains (uranium, thorium, and actinium series). This contamination consists of residues resulting from refining and processing uranium and thorium. Preparation of these sites for release to unrestricted private use will involve the assistance of construction workers, many of whom have limited knowledge of the hazards associated with radioactive materials. Therefore, there is a need to educate these workers in the fundamentals of radioactive material handling to minimize exposures and possible spread of contamination. This training should disseminate relevant information at an appropriate educational level and should instill a cautious, common-sense attitude toward the handling of radioactive materials. The training should emphasize basic information concerning environmental radiation within a context of relative risk. A multi-media format, including colorful visual aids, demonstration, and discussion, should be used to maximize motivation and retention. A detailed, proposed training program design is presented

Test and application of a general process-based dynamic coastal mass-balance model for contaminants using data for radionuclides in the Dnieper-Bug estuary

International Nuclear Information System (INIS)

Hakanson, Lars; Lindgren, Dan

2009-01-01

In this work a general, process-based mass-balance model for water contaminants for coastal areas at the ecosystem scale (CoastMab) is presented and for the first time tested for radionuclides. The model is dynamic, based on ordinary differential equations and gives monthly predictions. Connected to the core model there is also a sub-model for contaminant concentrations in fish. CoastMab calculates sedimentation, resuspension, diffusion, mixing, burial and retention of the given contaminant. The model contains both general algorithms, which apply to all contaminants, and substance-specific parts (such as algorithms for the particulate fraction, diffusion, biouptake and biological half-life). CoastMab and the sub-model for fish are simple to apply in practice since all driving variables may be readily accessed from maps or regular monitoring programs. The separation between the surface-water layer and the deep-water layer is not done as in most traditional models from water temperature data but from sedimentological criteria. Previous versions of the models for phosphorus and suspended particulate matter (in the Baltic Sea) have been validated and shown to predict well. This work presents modifications of the model and tests using two tracers, radiocesium and radiostrontium (from the Chernobyl fallout) in the Dnieper-Bug estuary (the Black Sea). Good correlations are shown between modeled and empirical data, except for the month directly after the fallout. We have, e.g., shown that: 1. The conditions in the sea outside the bay are important for the concentrations of the substances in water, sediments and fish within the bay, 2. We have demonstrated 'biological,' 'chemical' and 'water' dilution, 3. That the water chemical conditions in the bay influence biouptake and concentrations in fish of the radionuclides and 4. That the feeding behaviour of the coastal fish is very important for the biouptake of the radionuclides

Disruptive Event Biosphere Doser Conversion Factor Analysis

Energy Technology Data Exchange (ETDEWEB)

M. Wasiolek

2000-12-28

The purpose of this report was to document the process leading to, and the results of, development of radionuclide-, exposure scenario-, and ash thickness-specific Biosphere Dose Conversion Factors (BDCFs) for the postulated postclosure extrusive igneous event (volcanic eruption) at Yucca Mountain. BDCF calculations were done for seventeen radionuclides. The selection of radionuclides included those that may be significant dose contributors during the compliance period of up to 10,000 years, as well as radionuclides of importance for up to 1 million years postclosure. The approach documented in this report takes into account human exposure during three different phases at the time of, and after, volcanic eruption. Calculations of disruptive event BDCFs used the GENII-S computer code in a series of probabilistic realizations to propagate the uncertainties of input parameters into the output. The pathway analysis included consideration of different exposure pathway's contribution to the BDCFs. BDCFs for volcanic eruption, when combined with the concentration of radioactivity deposited by eruption on the soil surface, allow calculation of potential radiation doses to the receptor of interest. Calculation of radioactivity deposition is outside the scope of this report and so is the transport of contaminated ash from the volcano to the location of the receptor. The integration of the biosphere modeling results (BDCFs) with the outcomes of the other component models is accomplished in the Total System Performance Assessment (TSPA), in which doses are calculated to the receptor of interest from radionuclides postulated to be released to the environment from the potential repository at Yucca Mountain.

Vertical soil migration of radionuclide fallout from the Chernobyl' accident

International Nuclear Information System (INIS)

Silant'ev, A.N.; Shkuratova, I.G.; Bobovnikova, T.I.

1989-01-01

The most suitable model for describing the behavior of radionuclide fallout on a soil surface is quasidiffusion transfer with directional transfer taken into account. The parameter values for this have been determined previously and are supplemented by the results of this work. To investigate the initial radionuclide distribution along the soil profile, monolithic soil samples 5 cm thick were taken in June-September 1986 in areas which had been subjected to contamination due to the Chernobyl' accident. The samples taken were cut up into layers. The first layer, 0.5 cm thick, was cut off from the surface of the soil monolith together with the grass. The next layer cut off was also 0.5 cm thick. Then two layers, each 1 cm in thickness, were cut off. The thickness of the last layer was 2 cm. The vertical distribution of radionuclides along the soil profile which was examined may be called the initial distribution, which will then change due to nonimmediate migration of radionuclides in the soil. Based on the research which has been performed, the following conclusions may be drawn. One portion of the radionuclides resulting from fallout is trapped by plant cover, while the other enters immediately into the soil. For a thick plant covering, about 80% of the radionuclide fallout is sorbed by the grass; for sparse cover, about 40%. The radionuclides entering the soil along with rainwater penetrate into the soil depths, producing contamination which falls off exponentially with depth. The exponent index is close to 1 cm -1 . In a forest, the main amount of radionuclide fallout is trapped by litter. Approximately 10% of the contamination fallout penetrates beneath the litter

Direct measurement of homogeneously distributed radioactive air contamination with germanium detectors

International Nuclear Information System (INIS)

Sowa, W.

1990-01-01

Air contamination by γ emitting radionuclides was measured with a vertically arranged germanium detector, laterally shielded by a lead ring, and calibration factors and detection limits of a number of fission products determined. The possibility of measuring simultaneously existing air and soil contamination by measurements with and without lead shield is described. The change of detection limit of air contamination is presented for different soil contamination levels by the same radionuclide. Calibration factors are given to determine the dose rate on the ground due to air contamination by different radionuclides. (author)

Hydrology/Radionuclide Migration Program and related research activities

International Nuclear Information System (INIS)

Jones, M.A.

1992-02-01

This report presents the results of technical studies conducted under the Hydrology/Radionuclide Migration Program (HRMP) at the Nevada Test Site (NTS) for the period of October 1, 1985 through September 30, 1986. The HRMP was initiated in 1973 as the Radionuclide Migration Program to study and better understand the hydrologic systems of the NTS and potential movement and rates of movement of radionuclides and other contaminants injected into these systems by underground nuclear testing

Self-restoration of contaminated territories

International Nuclear Information System (INIS)

Arapis, G.; Sobotovich, E.; Bondarenko, G.; Sadolko, I.; Petrayev, E.; Sokolik, G.

1996-01-01

This paper illustrates the experience gained in the field of natural restoration of contaminated vast ecosystems. Prior to recommending a large-scale application of any rehabilitation technique, it is important to know the medium-and long- term intensity of self-restoration for most of the affected territories. Three main ways express the process of self-restoration: the natural radioactive decay, the transfer of radionuclides out of natural ecosystems and the ability of some pedological components to fixate the contaminants. The first way is a real decontamination process resulting in the removal from the biosphere of significant quantities of radionuclides. Indeed, during the last years the total activity of short-life-isotopes was decreased by a factor of some thousand and actually, the main contaminants are 137 Cs and 90 Sr which are decreasing according to their half-life. The two other ways of self-restoration are closely connected with radionuclides migration (vertical or/and horizontal) in soils. The vertical migration velocities of 137 Cs and 90 St in typical soils of contaminated regions in Ukraine and Belarus were evaluated annually during 9 years since the accident. In most of these soils the migration rate of 90 Sr seems higher than this of 137 Cs and ranges from 0.71 to 1.54 cm/year and 0.10 to 1.16 cm/year respectively. At present time the main part of radionuclides is located in the upper 10 cm layer of soils. The ability of soils components to immobilize the radionuclides was also investigated. From 1989 to 1994 approximately 57% of 137 Cs was converted in fixed forms and for the year 2000 it is expected that this percentage will be 80%. Finally, for total contaminated regions, the obtained results on vertical migration velocity of radionuclides as a function of the soil type, are presented under the form of a map in order to help decision makers to determine the feasibility and the methodology for restoration of areas contaminated by 137 Cs and 90

TERMOD II: an interactive code for analysing intake of radionuclides by man through terrestrial pathways

International Nuclear Information System (INIS)

Zach, R.

1978-11-01

An interactive code, TERMOD II, has been written in FORTRAN IV for the PDP 10. This code allows calculation of the time-dependent input of radionuclides through terrestrial pathways to man following an acute or accidental release. TERMOD II calculates daily input rates of radioactivity and the total intake rate over specified periods. To calculate these rates, TERMOD II uses the TERMOD model developed at Oak Ridge National Laboratory. This model includes three food types which can be contaminated by fallout radionuclides. Food crops and grass can be contaminated by direct foliar deposition and by root uptake. Milk and beef can be contaminated by direct foliar deposition and by root uptake. Milk and beef can be contaminated via ingestion of contaminated grass. The user of TERMOD II can choose from 78 different radionuclides. Additional radionuclides can be added as more data become available. Summaries of intake rates can be displayed at a local terminal or at an auxiliary high-speed printer. (author)

Mathematical simulation of sediment and radionuclide transport in estuaries

International Nuclear Information System (INIS)

Onishi, Y.; Trent, D.S.

1982-11-01

The finite element model LFESCOT (Flow, Energy, Salinity, Sediment and Contaminant Transport Model) was synthesized under this study to simulate radionuclide transport in estuaries to obtain accurate radionuclide distributions which are affected by these factors: time variance, three-dimensional flow, temperature, salinity, and sediments. Because sediment transport and radionuclide adsorption/desorption depend strongly on sizes or types of sediments, FLESCOT simulates sediment and a sediment-sorbed radionuclide for the total of three sediment-size fractions (or sediment types) of both cohesive and noncohesive sediments. It also calculates changes of estuarine bed conditions, including bed elevation changes due to sediment erosion/deposition, and three-dimensional distributions of three bed sediment sizes and sediment-sorbed radionuclides within the bed. Although the model was synthesized for radionuclide transport, it is general enough to also handle other contaminants such as heavy metals, pesticides, or toxic chemicals. The model was checked for its capability for flow, water surface elevation change, salinity, sediment and radionuclide transport under various simple conditions first, confirming the general validity of the model's computational schemes. These tests also revealed that FLESCOT can use large aspect ratios of computational cells, which are necessary in handling long estuarine study areas. After these simple tests, FLESCOT was applied to the Hudson River estuary between Chelsea and the mouth of the river to examine how well the model can predict radionuclide transport through simulating tidally influenced three-dimensional flow, salinity, sediment and radionuclide movements with their interactions

Impact of sensor detection limits on protecting water distribution systems from contamination events

International Nuclear Information System (INIS)

McKenna, Sean Andrew; Hart, David Blaine; Yarrington, Lane

2006-01-01

Real-time water quality sensors are becoming commonplace in water distribution systems. However, field deployable, contaminant-specific sensors are still in the development stage. As development proceeds, the necessary operating parameters of these sensors must be determined to protect consumers from accidental and malevolent contamination events. This objective can be quantified in several different ways including minimization of: the time necessary to detect a contamination event, the population exposed to contaminated water, the extent of the contamination within the network, and others. We examine the ability of a sensor set to meet these objectives as a function of both the detection limit of the sensors and the number of sensors in the network. A moderately sized distribution network is used as an example and different sized sets of randomly placed sensors are considered. For each combination of a certain number of sensors and a detection limit, the mean values of the different objectives across multiple random sensor placements are calculated. The tradeoff between the necessary detection limit in a sensor and the number of sensors is evaluated. Results show that for the example problem examined here, a sensor detection limit of 0.01 of the average source concentration is adequate for maximum protection. Detection of events is dependent on the detection limit of the sensors, but for those events that are detected, the values of the performance measures are not a function of the sensor detection limit. The results of replacing a single sensor in a network with a sensor having a much lower detection limit show that while this replacement can improve results, the majority of the additional events detected had performance measures of relatively low consequence.

A coupled classification - evolutionary optimization model for contamination event detection in water distribution systems.

Science.gov (United States)

Oliker, Nurit; Ostfeld, Avi

2014-03-15

This study describes a decision support system, alerts for contamination events in water distribution systems. The developed model comprises a weighted support vector machine (SVM) for the detection of outliers, and a following sequence analysis for the classification of contamination events. The contribution of this study is an improvement of contamination events detection ability and a multi-dimensional analysis of the data, differing from the parallel one-dimensional analysis conducted so far. The multivariate analysis examines the relationships between water quality parameters and detects changes in their mutual patterns. The weights of the SVM model accomplish two goals: blurring the difference between sizes of the two classes' data sets (as there are much more normal/regular than event time measurements), and adhering the time factor attribute by a time decay coefficient, ascribing higher importance to recent observations when classifying a time step measurement. All model parameters were determined by data driven optimization so the calibration of the model was completely autonomic. The model was trained and tested on a real water distribution system (WDS) data set with randomly simulated events superimposed on the original measurements. The model is prominent in its ability to detect events that were only partly expressed in the data (i.e., affecting only some of the measured parameters). The model showed high accuracy and better detection ability as compared to previous modeling attempts of contamination event detection. Copyright © 2013 Elsevier Ltd. All rights reserved.

Granulometric analysis of sediments containing transuranic radionuclides

International Nuclear Information System (INIS)

Smith, R.M.; Additon, M.K.

1980-11-01

A dry sieving technique using a sonic sifter was selected for the granulometric analysis of sediment samples containing radionuclide contamination. A sieve facility was established in the 234-5Z building for this purpose. Fifty-two contaminated sediment samples from the 216-Z-1A crib were sieved in the facility at a rate of two to four samples per day with no major problems. A comparison of particle size and radionuclide concentration indicated that there is no obvious benefit to particle size separation as a means of sediment decontamination, though an economic analysis will have to be conducted before a final decision can be made

Studies on distribution coefficient (Kd) of naturally occurring radionuclides in geological matrices

International Nuclear Information System (INIS)

Pandit, G.G.

2014-01-01

Accurate prediction of fate and transport of toxic and radioactive metals in the subsurface of uranium tailing pond sites is critical to the assessment of environmental impact and to the development of effective remediation technologies. The mobility of radionuclides and toxic metals is enhanced by acidification of tailings due to sulphide oxidation catalysed by microbial activity. Due to infiltration of water, there is a possibility of leaching of these radionuclides and toxic metals from the tailings pond to the ground water. Sorption onto mineral surfaces is an important mechanism for reducing radionuclide concentrations along ground water flow paths and retarding radionuclide migration to the accessible environment. Reactive transport of ground water contaminants often assume that the reaction governing the retardation of a particular contaminant or radionuclide can be described by simple partitioning constant, K d . This constant is assumed to account for all the reversible sorption processes affecting transport of the contaminant. Experimental determination of site-specific K d values is absolutely essential for the accurate estimation of reactive transport of these contaminants. The results of such studies would be helpful to model migration of these pollutants and to estimate the radiation dose to members of the public through groundwater drinking pathway at different distances from the tailings pond. In the present study it is clearly observed that K d values of most of the radionuclides are strongly dependent on different soil and ground water parameters. The relationships generated between distribution coefficient values of different radionuclides and different soil and ground water parameters can be used to generate look up table. And these relationships can also be used for the prediction of K d values of different radionuclides by using the different physico-chemical parameters of soil and ground water of the particular location

Elimination of effluents and wastes contaminated by radionuclides produced in installations authorized on the account of the Public Health Code - ASN guide nr 18 - Release of the 26/01/2012

International Nuclear Information System (INIS)

2012-01-01

This document aims at specifying the modalities of application of a decision taken by the ASN in January 2008 regarding the technical rules which the elimination of effluents and wastes contaminated by radionuclides must comply with. First, it describes the objective of the 'waste zoning' concept. Then, it addresses the management of contaminated wastes: general rules, wastes contaminated by radionuclides of very short period (less than 100 days) and of period longer than 100 days, and the management of wastes with 'hybrid risks'. It addresses the management of contaminated effluents: radioactive liquid effluent with a period either shorter or longer than 100 days, radioactive gaseous effluents. It addresses the warehousing conditions (premise design, exploitation rules). The other parts deal with the convention between several establishments within a same site (notably in the case of nuclear medicine departments), with the management plan, and with the agenda for the implementation of the ASN decision

MOIRA: a computerised decision support system for the restoration of radionuclide contaminated freshwater ecosystems

International Nuclear Information System (INIS)

Gallego, Eduardo; Brittain, J.E.; Hakanson, Lars; Heling, Rudie; Hofman, Dmitry; Monte, Luigi

2000-01-01

The radiation dose resulting from contamination of freshwater ecosystems due to the release of radioactive substances into the environment may be reduced by applying suitable countermeasures. The options for intervention are wide-ranging and can be broadly grouped into three main categories: chemical, physical and social countermeasures. In some cases, a combination of actions -or even the no action- may be the optimal strategy. Despite their benefits, intervention strategies may have detrimental effects of economic, ecological and social nature. Thus, it is of paramount importance to assess, by objective criteria, the global cost-benefit balance of different options. The MOIRA project (A MOdel based computerised system for management support to Identity optimal remedial strategies for Restoring radionuclide contaminated Aquatic ecosystems, European Commission contract FI4P-CT96-0036) has developed a user-friendly, computerised tool that will allow decision makers to choose optimal intervention strategies for freshwater ecosystems with different contamination scenarios. To achieve that goal, the MOIRA software system -apart from a user-friendly interface- incorporates several innovative aspects: - eographical information system (GIS) and databases to get to get the values of the model parameters at different locations in Europe. - redictive ecosystem models for the behaviour of radionuclides (namely Cs-137 and Sr-90) in catchments, lakes and rivers, complemented with models of the effect of the countermeasures on the environmental contamination levels. These models are based on an extensive use of aggregate parameters' that summarise, in single quantities, the effects of a variety of environmental processes. Methods for critical model testing, sensitivity and uncertainty analyses have been applied to them getting a high reliability. - cosystem index (EI) to handle the influence chemical remedial measures may have on the structure, reproduction and biomass of key

Transfer of radionuclides to man through environmental pathways

International Nuclear Information System (INIS)

Mitchell, N.T.

1974-01-01

The most widely accepted method in current use for the evaluation of environmental impact from releases of radioactivity that may cause human radiation exposure used an environmental pathway model. The more important aspects of the model involve the use of critical pathway techniques to set controls on the releases of radioactive material to the environment and to assess the human radiation exposure arising as a consequence. The basic concepts of the environmental pathway model and its application are discussed. The model depends on achieving an understanding of radionuclide behavior in the environment, from the moment of release up to the time when contamination results in radiation exposure to the public. Exposure may be as a result of contaminated material entering the body-as air, water or a foodstuff; alternatively, it may be due to radiation whose source is external to the body. For each of these types of exposure pathway the sequence of events can be divided up into a number of compartments, between which transfer takes place. Transfer along the pathway is a dynamic process and can be described mathematically in terms of transfer functions between interacting compartments. Alternatively, for the situation of a regular discharge resulting in a steady-state condition the relationship between compartments can be expressed as a 'concentration factor'. The derivation of both of these terms is described and some aspects of their use are discussed. The paper then goes on to discuss the types of environmental pathway that are encountered as a result of release of radionuclides to the atmospheric and aquatic environments. Disposal to the ground is regarded as a special case of release to the aquatic environment. Some ot the literature on the subject is reviewed in discussingthe better known pathways showing what, to date, have been the most important mechanisms of transfer of radionuclides to man. (author)

The flow of radionuclides through the Canadian archipelago

International Nuclear Information System (INIS)

Ellis, K.; Smith, J.N.

1999-01-01

The transport of contaminants to the Canadian Arctic by air and in water and their concentration through the marine food web has lead to enhanced levels of contaminants in several foods of Canadian northern inhabitants. Artificial radionuclides in the marine water can be used to determine water circulation and to trace contaminant transport through the Canadian Archipelago

Influence of climate changes on the migration ability of technogenic radionuclides

International Nuclear Information System (INIS)

Todorov, B.; Kovacheva, P.; Djingova, R.

2011-01-01

Full text: Global warming and climatic changes in the last decade focus the attention of scientists worldwide. Changes in climate variables (winds, precipitation, currents, temperature, etc.) affect the transport, transfer, and deposition of contaminants in the environment. Numerous investigations show the strong impact of climatic parameters like temperature and precipitations on soil characteristics, and especially on soil organic matter, which plays a significant role in the migration behaviour of the contaminants in the environment. This defines the need of special attention on elucidation of the impact of temperature and precipitations on the chemical behaviour of the radionuclides. This work presents initial results of a research project aiming to elucidate the influence of climate changes on the migration and bioaccumulation of natural and technogenic radionuclides in terrestrial ecosystems. Different types of soils were contaminated by technogenic radionuclides ( 241 Am, 137 Cs, and 60 Co) and conditioned under different temperatures and soil humidity, simulating sharp climatic variations. Chemical fractionation of the radionuclides was studied by using two different procedures for sequential extractions, followed by radiation detection by gamma-spectrometry. Evaluation of the chemical behaviour of the investigated radionuclides with respect to soil characteristics, temperature and humidity variations and duration of conditioning was performed. Initial conclusions on the influence of the climate changes on the migration ability of radionuclides of different oxidation states were made

Cardiointervalography investigation of the nervous system of children from the radionuclide contaminated districts

International Nuclear Information System (INIS)

Nedvetskaya, V.V.; Lyalikov, S.A.

1994-01-01

Using cardiointervalography the vegetative status of 177 children living in the supervised Belarus regions (more 15 Ci/km 2 of 137 Cs) and of 1291 children from the areas which are not contaminated with radionuclides is assessed. It is stated that the most characteristic peculiarity common for children living on supervised territories is an increase of the subcortical nervous centers activity, reinforcement of the central regulation stability, bettering of relations between the central and peripheral regulation profiles at rest and damage of these relations under physical load. Changes in the vegetative regulation developing in children from these districts are more pronounced in girls as compared to boys and are characterized by the nervous system sympathetic section tone decrease, by the liability to hyporeactivity accompanied by the parasympathetic section compensatory mechanisms tension. (author). 4 refs., 2 tabs

Long-term assessment of contaminated articles from the Chernobyl reactor.

Science.gov (United States)

Alkhomashi, N; Monged, M H E

2015-06-01

The Chernobyl accident caused a release of radioactive materials from the reactor into the environment. This event contaminated people, their surroundings and their personal property, especially in the zone around the reactor. Among the affected individuals were British students who were studying in Minsk and Kiev at the time of the Chernobyl accident. These students were exposed to external and internal radiation, and the individuals' articles of clothing were contaminated. The primary objective of this study was to analyze a sample of this contaminated clothing 20 years after the accident using three different detectors, namely, a BP4/4C scintillation detector, a Min-Con Geiger-Müller tube detector and a high-purity germanium (HPGe) detector. The clothing articles were initially assessed and found not to be significantly contaminated. However, there were several hot spots of contamination in various regions of the articles. The net count rates for these hot spots were in the range of 10.00 ± 3.16 c/s to 41.00 ± 6.40 c/s when the BP4/4C scintillation detector was used. The HPGe detector was used to identify the radionuclides present in the clothing, and the results indicated that the only active radionuclide was (137)Cs because of this isotope's long half-life. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pollen as indicator of radionuclide pollution

International Nuclear Information System (INIS)

Kirkham, M.B.; Corey, J.C.

1977-01-01

To assess hazards of radioactivity in the environment, agricultural scientists must identify plant and animal species which can be used as biological indicators of radionuclide contamination. In this experiments, the pollen-bee-honey system was chosen to study movement of radioactive elements in the plant-animal-man food chain. Pollen, bees, and honey were collected from different locations at a nuclear facility in South Carolina. They were analyzed for nine radionuclides and 22 stable elements. The results showed that pollen is a more sensitive indicator of pollution than bees or honey. If pollen-monitoring shows that an area has become polluted, hives and other sources of human and animal food should not be placed in the region until it is no longer contaminated. (author)

FOOD II: an interactive code for calculating concentrations of radionuclides in food products

International Nuclear Information System (INIS)

Zach, R.

1978-11-01

An interactive code, FOOD II, has been written in FORTRAN IV for the PDP 10 to allow calculation of concentrations of radionuclides in food products and internal doses to man under chronic release conditions. FOOD II uses models unchanged from a previous code, FOOD, developed at Battelle, Pacific Northwest Laboratories. The new code has different input and output features than FOOD and a number of options have been added to increase flexibility. Data files have also been updated. FOOD II takes into account contamination of vegetation by air and irrigation water containing radionuclides. Contamination can occur simultaneously by air and water. Both direct deposition of radionuclides on leaves, and their uptake from soil are possible. Also, animals may be contaminated by ingestion of vegetation and drinking water containing radionuclides. At present, FOOD II provides selection of 14 food types, 13 diets and numerous radionuclides. Provisions have been made to expand all of these categories. Six additional contaminated food products can also be entered directly into the dose model. Doses may be calculated for the total body and six internal organs. Summaries of concentrations in food products and internal doses to man can be displayed at a local terminal or at an auxiliary high-speed printer. (author)

Sensors and Automated Analyzers for Radionuclides

International Nuclear Information System (INIS)

Grate, Jay W.; Egorov, Oleg B.

2003-01-01

The production of nuclear weapons materials has generated large quantities of nuclear waste and significant environmental contamination. We have developed new, rapid, automated methods for determination of radionuclides using sequential injection methodologies to automate extraction chromatographic separations, with on-line flow-through scintillation counting for real time detection. This work has progressed in two main areas: radionuclide sensors for water monitoring and automated radiochemical analyzers for monitoring nuclear waste processing operations. Radionuclide sensors have been developed that collect and concentrate radionuclides in preconcentrating minicolumns with dual functionality: chemical selectivity for radionuclide capture and scintillation for signal output. These sensors can detect pertechnetate to below regulatory levels and have been engineered into a prototype for field testing. A fully automated process monitor has been developed for total technetium in nuclear waste streams. This instrument performs sample acidification, speciation adjustment, separation and detection in fifteen minutes or less

Modeling the Long-term Transport and Accumulation of Radionuclides in the Landscape for Derivation of Dose Conversion Factors

International Nuclear Information System (INIS)

Avila, Rodolfo Moreno; Ekstroem, Per-Anders; Kautsky, Ulrik

2006-01-01

To evaluate the radiological impact of potential releases to the biosphere from a geological repository for spent nuclear fuel, it is necessary to assess the long-term dynamics of the distribution of radionuclides in the environment. In this paper, we propose an approach for making prognoses of the distribution and fluxes of radionuclides released from the geosphere, in discharges of contaminated groundwater, to an evolving landscape. The biosphere changes during the temperate part (spanning approximately 20,000 years) of an interglacial period are handled by building biosphere models for the projected succession of situations. Radionuclide transport in the landscape is modeled dynamically with a series of interconnected radioecological models of those ecosystem types (sea, lake, running water, mire, agricultural land and forest) that occur at present, and are projected to occur in the future, in a candidate area for a geological repository in Sweden. The transformation between ecosystems is modeled as discrete events occurring every thousand years by substituting one model by another. Examples of predictions of the radionuclide distribution in the landscape are presented for several scenarios with discharge locations varying in time and space. The article also outlines an approach for estimating the exposure of man resulting from all possible reasonable uses of a potentially contaminated landscape, which was used for derivation of Landscape Dose Factors

Combining of radionuclides with constituent materials of marine algae

International Nuclear Information System (INIS)

Nakamura, Ryoichi; Nakahara, Motokazu; Ishii, Toshiaki; Ueda, Taishi; Shimizu, Chiaki.

1979-01-01

The relations between the accumulation-elimination of radionuclides and the constituent materials of marine algae were studied to determine more precisely the mechanism of the radioactive contamination of marine organisms. This will increase the information about the behavior of radionuclides in marine organisms in relation to the environmental conditions (temperature, physico-chemical state of radioisotope, and so on) and the biological conditions (feeding habits, species, and so on). Eisenia contaminated by 137 Cs and 106 Ru- 106 Rh was fractionated by solvent extraction into 6 fractions. The largest portion of 137 Cs was in the boiling water fraction; 106 Ru- 106 Rh was most extracted by 24% KOH solution. Elution patterns by Sephadex G-100 gel-filtration of samples differed largely from each other, both among the 3 kinds of radionuclides and between the 2 species of the algae. Therefore, the accumulation of the radionuclides by the marine algae was proved to be not only due to a physical absorption to the surface of the algae but also to the biological combining of the radionuclides with the constituents of the algae. Furthermore, it was found that radionuclides which combine with a few constituents of alga are not eliminated equally. This is considered to be useful for the physiological analysis of elimination curves. (author)

Guidebook for the treatment of accidental internal radionuclide contamination of workers

Energy Technology Data Exchange (ETDEWEB)

Bhattacharyya, M H [Argonne National Lab., IL (United States); Breitenstein, B D [Brookhaven National Lab., Upton, NY (United States); Metivier, H [CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire; Muggenburg, B A [ITRI, Albuquerque, NM (United States); Stradling, G N [National Radiological Protection Board, Chilton (United Kingdom); Volf, V [Kernforschungszentrum Karlsruhe GmbH (Germany)

1992-01-01

This book is intended as a guide to the treatment of victims following an accident in which radionuclides have entered the body. It is a practical guide based on a review of current treatments to remove radionuclides from the body and prevent radiation-induced disease. This book should be used by occupational physicians, emergency room physicians, health physicists, paramedics and emergency personnel, nurses, and other related medical personnel. It is intended to provide an overview of the subject and practical information for treating and caring for persons exposed to radionuclides. (author).

Radioactive contamination of the Byelorussia and Russia Territories after Chernobylsk accident

International Nuclear Information System (INIS)

Orlov, M.Yu.; Snykov, V.P.; Khvalenskij, Yu.A.; Teslenko, V.P.; Korenev, A.I.

1992-01-01

From the data on gamma-radiation dose rates, on meteorological data and conditions of atmospheric transfer at the first days following Chernobylsk NPP accident it was shown that soil contamination of Byelorussian and Russian territories with radionuclides was mainly caused by atmospheric precipitations on 28-30 April of 1986. Spatial distribution of radionuclide activity revealed that contamination of Russian territories were similar in isotopic content and radionuclide content considerably differed from contamination of Byelorussian territories

Flotation separation of uranium from contaminated soils

International Nuclear Information System (INIS)

Misra, M.; Mehta, R.; Garcia, H.; Chai, C.D.; Smith, R.W.

1995-01-01

The volume of low-level contaminated soil at the Department of Energy's Nuclear Weapon Sites are in the order of several million tons. Most of the contaminants are uranium, plutonium, other heavy metals and organic compounds. Selected physical separation processes have shown demonstrated potential in concentrating the radionuclides in a small fraction of the soil. Depending upon the size, nature of bonding and distributions of radionuclides, more than 90% of the radionuclide activity can be concentrated in a small volume of fraction of the soil. The physico-chemical separation processes such as flotation in a mechanical and microbubble tall column cell have shown promising applications in cleaning up the high volume contaminated soil

Radionuclide inventories for the F- and H-area seepage basin groundwater plumes

Energy Technology Data Exchange (ETDEWEB)

Hiergesell, Robert A [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kubilius, Walter P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-05-01

Within the General Separations Areas (GSA) at the Savannah River Site (SRS), significant inventories of radionuclides exist within two major groundwater contamination plumes that are emanating from the F- and H-Area seepage basins. These radionuclides are moving slowly with groundwater migration, albeit more slowly due to interaction with the soil and aquifer matrix material. The purpose of this investigation is to quantify the activity of radionuclides associated with the pore water component of the groundwater plumes. The scope of this effort included evaluation of all groundwater sample analyses obtained from the wells that have been established by the Environmental Compliance & Area Completion Projects (EC&ACP) Department at SRS to monitor groundwater contamination emanating from the F- and H-Area Seepage Basins. Using this data, generalized groundwater plume maps for the radionuclides that occur in elevated concentrations (Am-241, Cm-243/244, Cs-137, I-129, Ni-63, Ra-226/228, Sr-90, Tc-99, U-233/234, U-235 and U-238) were generated and utilized to calculate both the volume of contaminated groundwater and the representative concentration of each radionuclide associated with different plume concentration zones.

Exposure of birds to radionuclides and other contaminants in Special Protection Areas (SPAs) in North-West England

International Nuclear Information System (INIS)

Marshall, K.; Watson, S.; McDonald, P.; Copplestone, D.; Watts, S.J.

2010-01-01

There has been a decline in the population of some bird species at Morecambe Bay and the Solway Firth Special Protected Areas in North-West England during the last fifty years. It was suggested that the declines were caused, in part, by contaminants in the food and environment, primarily from the radioactive effluent discharge from the Sellafield Ltd nuclear fuel reprocessing plant in Cumbria. This study analysed bird feathers and tissues, vegetation and sediment for radionuclides, metals and persistent organic compounds. The non-radionuclide results were all low compared to relevant action limits. The ERICA model was used with field data to estimate the radiological dose to birds from exposure to 137 Cs and 241 Am with results between 1.26 to 3.83 μGy h -1 , below the ERICA screening level of 10 μGy h -1 and within the IAEA 40 μGy h -1 guideline value below which potential adverse impacts on biota are unlikely. The study showed no link between bird population decline and anthropogenic discharges to the SPAs.

Behaviour and fate radionuclides in soils. Mathematical modelling and experimental investigations

International Nuclear Information System (INIS)

Rovdan, E.N.

2003-01-01

The uncontrolled release of radionuclides as result of Chernobyl accident has led to contamination of 23% of territory of Republic of Belarus. Soil has high capacity to adsorb radionuclides and their intensive sorption provides the creation of a long-lived radionuclide source in a terrestrial environment. In the management of the contaminated areas and application of a countermeasure strategy it is extremely important to know the environmental mechanisms governing the behaviour of radionuclides in soils. Basic attention in the work is paid to the study of 137 Cs and 90 Sr because they are the main radionuclides from the view point of radioactive danger in polluted areas. The main features and processes that control radionuclide behaviour in soil have been analysed. On the basis of natural researches, lab test and mathematical modelling the impact of physical-chemical factors and the soil component composition changes upon the radionuclides migration and sorption in natural dispersed systems (peat, sand, bentonite, kaolin, sapropel) has been investigated. The investigations done allowed to substantiate the mathematical models of the radionuclides migration in the regions of positive and negative temperatures, to develop methods of experimental identification of main transfer characteristics and to compile a data base for these models. (orig.)

CRITICAL RADIONUCLIDE AND PATHWAY ANALYSIS FOR THE SAVANNAH RIVER SITE

Energy Technology Data Exchange (ETDEWEB)

Jannik, T.

2011-08-30

This report is an update to the analysis, Assessment of SRS Radiological Liquid and Airborne Contaminants and Pathways, that was performed in 1997. An electronic version of this large original report is included in the attached CD to this report. During the operational history (1954 to the present) of the Savannah River Site (SRS), many different radionuclides have been released to the environment from the various production facilities. However, as will be shown by this updated radiological critical contaminant/critical pathway analysis, only a small number of the released radionuclides have been significant contributors to potential doses and risks to offsite people. The analysis covers radiological releases to the atmosphere and to surface waters, the principal media that carry contaminants offsite. These releases potentially result in exposure to offsite people. The groundwater monitoring performed at the site shows that an estimated 5 to 10% of SRS has been contaminated by radionuclides, no evidence exists from the extensive monitoring performed that groundwater contaminated with these constituents has migrated off the site (SRS 2011). Therefore, with the notable exception of radiological source terms originating from shallow surface water migration into site streams, onsite groundwater was not considered as a potential exposure pathway to offsite people. In addition, in response to the Department of Energy's (DOE) Order 435.1, several Performance Assessments (WSRC 2008; LWO 2009; SRR 2010; SRR 2011) and a Comprehensive SRS Composite Analysis (SRNO 2010) have recently been completed at SRS. The critical radionuclides and pathways identified in these extensive reports are discussed and, where applicable, included in this analysis.

Evaluation of radionuclide contamination in the vicinity of the cunha baixa and quinta do bispo old uranium mines

International Nuclear Information System (INIS)

Pereira, A.J.S.C.; Neves, L.J.P.F.; Dias, J.M.M.; Barbosa, S.V.T.

2004-01-01

The Cunha Baixa and Quinta do Bispo uranium mines were some of the most important exploitations in Portugal and shared a common geological setting, composed of metasedimentary enclaves in hercynian porphyritic granites. The exploitation of Cunha Baixa began as an underground mine and later evolved to an open-pit; Quinta do Bispo was exclusively exploited as an open-pit. Heap leaching techniques were used in both mines to recover uranium from low-grade ores (300-500 ppm). The mining activities produced large amounts of waste, currently deposited in several tailings. To evaluate the degree and extension of the contamination of the environment, the radionuclides of the U-chain, as well as other chemical elements, were measure in samples of water (116), stream sediments (8) and soils (26), collected in the mining area and its vicinity. The activity of the radionuclides in the different environmental compartments is highly variable, and the modelling by multivariate techniques based on discriminant analysis, allow to separate the samples with chemical signature changed by the mine workings from those that only contain the variability imposed by geology or other anthropogenic activities. Mining contamination is mainly restricted to the surroundings of the studied mines and the worst environmental situation occurs in soils close to Cunha Baixa mine, as a result of the illegal use for irrigation of water collected in the wastewater treatment plant, as well as from resurgences in the tailings. (author)

A hybrid method for the simulation of radionuclide contaminant plumes in heterogeneous, unsaturated formations

International Nuclear Information System (INIS)

Aquino, J.; Pereira, T.J.; Souto, H.P. Amaral; Francisco, A.S.

2009-01-01

The decision concerning the location of sites for nuclear waste repositories in the subsurface depends upon the long-term containment capabilities of hydrogeological environments. The numerical simulation of the multiphase flow and contaminant transport that take place in this problem is an important tool to help engineers and scientists in selecting appropriate sites. In this paper, we employ a hybrid strategy that combines an Eulerian approximation scheme for the underlying two-phase flow problem with a locally conservative Lagrangian method to approximate the transport of radionuclide. This Lagrangian scheme is computationally efficient and virtually free of numerical diffusion. In order to face unsaturated and heterogeneous problems, four extensions in the Lagrangian scheme are implemented. To show the effectiveness of the improved version we perform a grid refinement study. (author)

Uptake by plants of radionuclides from FUSRAP waste materials

International Nuclear Information System (INIS)

Knight, M.J.

1983-04-01

Radionuclides from FUSRAP wastes potentially may be taken up by plants during remedial action activities and permanent near-surface burial of contaminated materials. In order to better understand the propensity of radionuclides to accumulate in plant tissue, soil and plant factors influencing the uptake and accumulation of radionuclides by plants are reviewed. In addition, data describing the uptake of the principal radionuclides present in FUSRAP wastes (uranium-238, thorium-230, radium-226, lead-210, and polonium-210) are summarized. All five radionuclides can accumulate in plant root tissue to some extent, and there is potential for the translocation and accumulation of these radionuclides in plant shoot tissue. Of these five radionuclides, radium-226 appears to have the greatest potential for translocation and accumulation in plant shoot tissue. 28 references, 1 figure, 3 tables

Uptake by plants of radionuclides from FUSRAP waste materials

Energy Technology Data Exchange (ETDEWEB)

Knight, M.J.

1983-04-01

Radionuclides from FUSRAP wastes potentially may be taken up by plants during remedial action activities and permanent near-surface burial of contaminated materials. In order to better understand the propensity of radionuclides to accumulate in plant tissue, soil and plant factors influencing the uptake and accumulation of radionuclides by plants are reviewed. In addition, data describing the uptake of the principal radionuclides present in FUSRAP wastes (uranium-238, thorium-230, radium-226, lead-210, and polonium-210) are summarized. All five radionuclides can accumulate in plant root tissue to some extent, and there is potential for the translocation and accumulation of these radionuclides in plant shoot tissue. Of these five radionuclides, radium-226 appears to have the greatest potential for translocation and accumulation in plant shoot tissue. 28 references, 1 figure, 3 tables.

Chemical controls on subsurface radionuclide transport

International Nuclear Information System (INIS)

King, K.J.; Killey, R.W.D.

1990-01-01

Chemical and biochemical processes can affect the movement of contaminants in groundwater. Materials can be almost completely removed from circulation by processes such as precipitation and coprecipitation. Organic compounds or contaminants that are hazardous may be degraded or formed during groundwater transport. Studies at the Chalk River Laboratories of AECL have focused on radionuclide transport, although other contaminants have been and are being investigated. This paper summarizes findings from research that extends back more than 30 years. Much of the work on reactive contaminant transport has centered on 90 Sr; other contaminants have also been considered, however, and features of their behaviour are also reviewed. (25 refs., 5 figs., 4 tabs.)

Natural and Synthetic Barriers to Immobilize Radionuclides

International Nuclear Information System (INIS)

Um, W.

2011-01-01

The experiments of weathering of glass waste form and the reacted sediments with simulated glass leachates show that radionuclide sequestration can be significantly enhanced by promoting the formation of secondary precipitates. In addition, synthetic phosphate-bearing nanoporous material exhibits high stability at temperature and has a very high K d value for U(VI) removal. Both natural and synthetic barrier materials can be used as additional efficient adsorbents for retarding transport of radionuclides for various contaminated waste streams and waste forms present at U. S. Department of Energy clean-up sites and the proposed geologic radioactive waste disposal facility. In the radioactive waste repository facility, natural or synthetic materials are planned to be used as a barrier material to immobilize and retard radionuclide release. The getter material can be used to selectively scavenge the radionuclide of interest from a liquid waste stream and subsequently incorporate the loaded getters in a cementitious or various monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides form monolithic waste forms by being emplaced as a backfill barrier material around the wastes or waste form to minimize the potential around the wastes or waste form to minimize the potential hazard of leached radioactive wastes. The barrier material should be highly efficient to sequester radionuclides and possess physical and chemical stability for long-term exposure to severe weathering conditions. Because potential leaching of radionuclides depends on various environmental and weathering conditions of the near-field repository, the barrier materials must be durable and not disintegrate under a range of moisture, temperature, pressure, radiation, Eh, ph. and

Radionuclides: Accumulation and Transport in Plants.

Science.gov (United States)

Gupta, D K; Chatterjee, S; Datta, S; Voronina, A V; Walther, C

Application of radioactive elements or radionuclides for anthropogenic use is a widespread phenomenon nowadays. Radionuclides undergo radioactive decays releasing ionizing radiation like gamma ray(s) and/or alpha or beta particles that can displace electrons in the living matter (like in DNA) and disturb its function. Radionuclides are highly hazardous pollutants of considerable impact on the environment, food chain and human health. Cleaning up of the contaminated environment through plants is a promising technology where the rhizosphere may play an important role. Plants belonging to the families of Brassicaceae, Papilionaceae, Caryophyllaceae, Poaceae, and Asteraceae are most important in this respect and offer the largest potential for heavy metal phytoremediation. Plants like Lactuca sativa L., Silybum marianum Gaertn., Centaurea cyanus L., Carthamus tinctorius L., Helianthus annuus and H. tuberosus are also important plants for heavy metal phytoremediation. However, transfer factors (TF) of radionuclide from soil/water to plant ([Radionuclide]plant/[Radionuclide]soil) vary widely in different plants. Rhizosphere, rhizobacteria and varied metal transporters like NRAMP, ZIP families CDF, ATPases (HMAs) family like P1B-ATPases, are involved in the radio-phytoremediation processes. This review will discuss recent advancements and potential application of plants for radionuclide removal from the environment.

Permissible annual depositions and radionuclide concentrations in air

International Nuclear Information System (INIS)

Belyaev, V.A.; Golovko, M.Yu.

1993-01-01

It is established that it necessary to take into account the other ways of radionuclide intake apart from the inhalation one when determining the standards for radionuclide contamination of the atmospheric air. Whereby it is proposed to standardize annual depositions rather than permissible concentration in the atmospheric air for the ways related to radionuclide releases on the ground surface, which is explained by ambiguity of their dry deposition rate from the air. Formulae and results of calculation of standard characteristics are presented. The permissible radionuclide depositions, related to the intake through food chains are calculated with account for diet diversity, agroclimatic and phenological parameters in different regions of the country

Factors influencing the transfer of radionuclides in agricultural food chains

International Nuclear Information System (INIS)

Vandecasteele, C.M.; Zeevaert, Th.; Kirchmann, R.

1991-01-01

The applications of nuclear energy have led and will continue to lead to routine or accidental discharges of radioactive elements into the atmospheric and/or aquatic environment resulting in the exposure of populations to ionising radiations. The radionuclides released into the atmosphere are transported downwind, dispersed by the atmospheric mixing phenomena and progressively settled by deposition processes. During the passage of the radioactive cloud, people are irradiated externally as well as internally by inhalation. After the passage of the cloud, exposure of the population continues via three main pathways: external irradiation from the radionuclides deposited on the ground, inhalation of resuspended contaminated particles and ingestion of contaminated food products. When discharged into aquatic systems, the radionuclides can be partly removed from the aqueous phase by adsorption on suspended solids and bottom sediments. As the radioactivity disperses, there is a continuing exchange between water and solid phases. The contaminated sediments deposited on the banks of rivers, lakes and coastal area lead to external irradiation of people spending time at these sites. The residual activity in water exposes man internally through the ingestion of drinking water and food products, contaminated by irrigation of vegetation and ingestion of water by livestock. Among the various exposure pathways, the main route of entry of fission products and most other artificial radionuclides into man has been identified as uptake from the diet. Since agricultural products constitute the basic diet of most populations, the fate and behavior of radionuclides in agricultural ecosystems are of primary importance when assessing the exposure risk of man from environmental releases of radioactivity. 69 refs., 4 figs

Idaho radionuclide exposure study: Literature review

International Nuclear Information System (INIS)

Baker, E.G.; Freeman, H.D.; Hartley, J.N.

1987-10-01

Phosphate ores contain elevated levels of natural radioactivity, some of which is released to the environment during processing or use of solid byproducts. The effect of radionuclides from Idaho phosphate processing operations on the local communities has been the subject of much research and study. The literature is reviewed in this report. Two primary radionuclide pathways to the environment have been studied in detail: (1) airborne release of volatile radionuclides, primarily 210 Po, from calciner stacks at the two elemental phosphorus plants; and (2) use of byproduct slag as an aggregate for construction in Soda Springs and Pocatello. Despite the research, there is still no clear understanding of the population dose from radionuclide emissions, effluents, and solid wastes from phosphate processing plants. Two other potential radionuclide pathways to the environment have been identified: radon exhalation from phosphogypsum and ore piles and contamination of surface and ground waters. Recommendations on further study needed to develop a data base for a complete risk assssment are given in the report

Real-time support for precision excavation of radionuclide-contaminated soils

International Nuclear Information System (INIS)

Durham, L. A.; Johnson, R. L.

2003-01-01

Traditional approaches to excavation design for sites with radionuclide-contaminated soils generally involve work plans with fixed excavation footprints and post-excavation verification sampling. Recent advancements in real-time data collection systems, combined with data loggers, location control systems, and secure project-support Web sites, allow for an alternative, more precise approach to excavation design and implementation. In this mode, traditional work plans are replaced with dynamic work plans. Excavation efforts are organized by lift, with real-time dig face screening performed and the data for each lift analyzed, before excavation continues. Rather than specifying excavation footprints, dynamic work plans identify the decision logic that will be used to determine footprints based on real-time data collection. The level of investment in excavation support data collection can be balanced against potential cost savings realized through waste stream minimization. Secure project support Web sites ensure that data sets generated during the remediation process are readily accessible to all who need to see them, whether they are on site or not. These include regulators, program managers, and technical support staff. This type of Web site allows for quick problem resolution, increased transparency in field decision making, and more efficient allocation of expensive technical staff time

Elucidating key factors affecting radionuclide aging in soils

Energy Technology Data Exchange (ETDEWEB)

Roig, M. [Universitat Politecnica Catalunya, Institut de Tecniques Energetiques, Barcelona (Spain); Rigola, A.; Vidal, M.; Rauret, G. [Barcelona Univ., Dept. de Quimica Analitica (Spain)

2004-07-01

Mechanistic studies allow at present to describe the processes governing the short-term interaction of radiostrontium and radiocaesium in soils. The initial sorption step can be described through the estimation of the soil-soil solution distribution coefficient from soil parameters, as cationic exchange capacity, radiocaesium interception potential and concentration of competing ions in the soil solution. After the initial soil-radionuclide interaction, a fraction of radionuclide is no longer available for exchange with the solution, and it remains fixed in the solid fraction. At present, the initial fixed fraction of a radionuclide in a given soil cannot be predicted from soil properties. Besides, little is known about soil and environmental factors (e.g., temperature; hydric regime) provoking the increase in the fixed fraction with time, the so-called aging process. This process is considered to control the reduction of food contamination with time at contaminated scenarios. Therefore, it is crucial to be able to predict the radionuclide aging in the medium and long term for a better risk assessment, especially when a decision has to be made between relying on natural attenuation versus implementing intervention actions. Here we study radiostrontium and radiocaesium aging in a set of soils, covering a wide range of soil types of contrasting properties (e.g., loamy calcareous; podzol; chernozem, organic). Three factors are separately and simultaneously tested: time elapsed since contamination, temperature and hydric regime. Changes in the radionuclide fixed fraction are estimated with a leaching test based on the use of a mild extractant solution. In addition to this, secondary effects on the radiocaesium interception potential in various soils are also considered. (author)

Elaboration of methods for assessment of radio-ecological safety state of objects, situated on the territories contaminated with Chernobyl radionuclides

International Nuclear Information System (INIS)

Saltanov, Eugene; Saltanova, Irina

2008-01-01

The main purpose of assessment of radio-ecological state of object is to elaborate recommendations to reduce both radiation dose and negative action of other contaminators on human organism. The basis of objects' ecological safety assessment is considering complex influence of multiple negative factors, such as radioactive contamination, firstly, and air, water, soil and noise pollution, secondly. The objects of assessments are social, industrial, rural enterprises and their production: school buildings and territories, all kinds of recreational institutions, civil buildings, etc. The described method is embodied in a computer program, which enables calculation of integral indicator of contamination and gives information about object's safety state. The results of the work may be proposed to the corresponding supervisor institutions as a prototype of practical guidance to control ecological state of the objects and territories. Particularly, the proposed methods are necessary to determine the order of measures, normally undertaken to deactivate objects, and to provide unified approach to radio-ecological safety assessment of objects, situated in the territories contaminated with Chernobyl radionuclides. (author)

Experimental studies on decontamination in first aid for contaminated wounds

International Nuclear Information System (INIS)

Kusama, Tomoko; Ogaki, Kazushi; Yoshizawa, Yasuo

1982-01-01

The present study was designed to investigate the decontamination procedures in first aid for wounds contaminated with radionuclides. Abrasion of mouse skin was contaminated with 58 CoCl 2 . Irrigation by decontamination fluids began at 2 min after administration of the radionuclide and continued for 14 min. Tap water, 0.5% Hyamine solution or 10% Ca-DTPA solution were used as the decontamination fluids. Radioactivities of whole body, wounded skin surface and washed solution were measured with an animal counter with 5 cm NaI(Tl) and a well-type auto-gamma-counter. Decontamination effectiveness were expressed as follows: (1) absorption rate of radionuclide through the wound and (2) residual rate of radionuclide on the wound. More than 20% of the radionuclide applied on the wounded skin was absorbed in 15 min after contamination. The absorption rate decreased to 2% by the decontamination procedures. The Ca-DTPA solution reduced the residual rate of radionuclide on the wounds. The results suggested that the decontamination for the contaminated wounds should begin as soon as possible. Irrigation with 0.5% Hyamine solution has been advocated for the decontamination in the first aid. (author)

ITE CHARACTERIZATION TO SUPPORT CONCEPTUAL MODEL DEVELOPMENT FOR SUBSURFACE RADIONUCLIDE TRANSPORT

Science.gov (United States)

Remediation of radionuclide contaminants in ground water often begins with the development of conceptual and analytical models that guide our understanding of the processes controlling radionuclide transport. The reliability of these models is often predicated on the collection o...

Radionuclides, Heavy Metals and Fluoride Contamination in Al Bahira Aquifer, Youssoufia Area, Morocco

Energy Technology Data Exchange (ETDEWEB)

Agma, T. T; Bouchaou, L.; Ettayfi, N.; Lgourna, Z.; Boutaleb, S. [Ibn Zohr University, Applied Geology and Geo-Environment Laboratory, Cite Dakhla, Agadir 80060 (Morocco); Warner, N.; Vengosh, A. [Duke University, Division of Earth and Ocean Sciences, Durham, NC 27708 (United States)

2013-07-15

This study investigates the geochemistry and quantity of trace metals and naturally occurring radionuclides (Ra, U) in the shallow groundwater in the western part of the Al Bahira aquifer (Phosphate Plateau) located in west central Morocco. Groundwater is characterized by a wide salinity range (TDS of 540 to 9286 mg/l) and shows systematic linear relationships between the major dissolved constituents. These relationships suggest that the mixing of a single saline source and fresh water controls the quality of groundwater. Fluoride, uranium, selenium, and arsenic concentrations are also correlated with salinity. The activity concentrations of Radium-226 exceed the US-EPA drinking water standard. Radium-226 activity in the groundwater is not directly related to salinity and might be affected by other factors such as water temperature. The low ratios of the short lived Ra-224 to Ra-223 ({approx}2) indicate that Ra was derived from a uranium rich source with a low Th/U ratio in the rock source, which is consistent with the Urich lithology of the aquifer (e.g., phosphate rocks). The high levels of contaminants found in the shallow groundwater samples have important health implications for the local population, as shallow groundwater is used for drinking water in the rural communities northwest of Marrakech and these contaminants pose potential serious health problems (e.g., dental fluorosis, kidney disease, and bone cancer). (author)

A methodology for determining optimal durations for the use of contaminated crops as fodder following a nuclear accident using a dynamic food-chain model

International Nuclear Information System (INIS)

Hwang, Won Tae; Han, Moon Hee; Cho, Gyuseong

2000-01-01

A methodology for determining optimal durations for the use of contaminated crops as fodder was designed based on cost-benefit analysis. Illustrative results of the application of this methodology to pigs are presented for the hypothetical deposition of radionuclides on August 15 when a number of crops are fully developed in Korean agricultural conditions. For investigating the appropriateness of the use of contaminated crops as fodder, the net benefit from this action was compared with the imposition of a ban on human consumption of contaminated crops without alternative use. The time-dependent radionuclide concentrations in crops and pork after the deposition event were predicted from a dynamic food-chain model DYNACON. The net benefit from the actions was quantitatively evaluated in terms of cost equivalent of the doses incurred or averted and the monetary costs needed to implement the action. The optimal duration for the use of contaminated crops as fodder depended on a number of factors such as radionuclide, variety of crops fed as fodder and duration of the action. Such action was more cost effective for 137 Cs deposition than for 90 Sr or 131 I deposition. The use of contaminated crops as fodder can be an effective response to a public reluctance to consume contaminated crops

Ways of investigating radionuclide migration processes in the lithosphere and hydrosphere

International Nuclear Information System (INIS)

Belousova, A.P.; Shmakov, A.I.; Galaktionova, O.V.

1994-01-01

In Russia, until recently, it was considered that groundwater was protected from surface radioactive contamination by soil and rocks in the zone aeration. Groundwater was not a subject of radiation control. The accident at the Chernobyl Nuclear Power Plant showed, however, that groundwater is vulnerable to radioactive contamination. In this connection, the vulnerability of groundwater to and the problems of protecting groundwater from radioactive contamination became urgent. The assessment of natural protection of groundwater from radioactive contamination is now considered a top priority. The zone of aeration is generally considered to be the zone separating groundwater from surface contamination. In respect to radioactive contamination, soils that may fix a large quantity of radionuclides serve as a protection zone of a higher order. The mapping of protectibility was done for each radionuclide taking into consideration the specific structure of the flow medium and migration properties of a radionuclide. 90 Sr and 137 Cs have different mechanisms of transport; convective transport is characteristic of the former and diffusive transfer of the latter. This is conditioned by different physico-chemical properties of the radionuclides and principally by their sorption capacities. The coefficient of distribution of 90 Sr is in many times less than the coefficient of distribution of 137 Cs. The environmental protection problem in regions with nuclear power plants and in areas subjected to radioactive contamination may be solved using a monitoring, system including interrelated systems of observation and prediction of the lithosphere and the hydrosphere. The problem of mathematical modeling of migration processes is related to the complexities of modeling the processes of flow, mass transfer, and the accompanying physicochemical processes in zones of full and partial saturation, as well as difficulties in mathematical calculations. 4 refs

Detection of water-quality contamination events based on multi-sensor fusion using an extented Dempster–Shafer method

International Nuclear Information System (INIS)

Hou, Dibo; He, Huimei; Huang, Pingjie; Zhang, Guangxin; Loaiciga, Hugo

2013-01-01

This study presents a method for detecting contamination events of sources of drinking water based on the Dempster–Shafer (D-S) evidence theory. The detection method has the purpose of protecting water supply systems against accidental and intentional contamination events. This purpose is achieved by first predicting future water-quality parameters using an autoregressive (AR) model. The AR model predicts future water-quality parameters using recent measurements of these parameters made with automated (on-line) water-quality sensors. Next, a probabilistic method assigns probabilities to the time series of residuals formed by comparing predicted water-quality parameters with threshold values. Finally, the D-S fusion method searches for anomalous probabilities of the residuals and uses the result of that search to determine whether the current water quality is normal (that is, free of pollution) or contaminated. The D-S fusion method is extended and improved in this paper by weighted averaging of water-contamination evidence and by the analysis of the persistence of anomalous probabilities of water-quality parameters. The extended D-S fusion method makes determinations that have a high probability of being correct concerning whether or not a source of drinking water has been contaminated. This paper's method for detecting water-contamination events was tested with water-quality time series from automated (on-line) water quality sensors. In addition, a small-scale, experimental, water-pipe network was tested to detect water-contamination events. The two tests demonstrated that the extended D-S fusion method achieves a low false alarm rate and high probabilities of detecting water contamination events. (paper)

Radionuclides in domestic and imported foods in the United States, 1987-1992

International Nuclear Information System (INIS)

Cunningham, W.C.; Anderson, D.L.; Baratta, E.J.

1994-01-01

Findings from the U.S. Food and Drug Administration's Radionuclides in Foods program are summarized for foods collected between October 1, 1986, and September 30, 1992. Concentrations of radionuclide activity in the Total Diet Study and reactor-survey foods were in Range I or low in Range II of the surveillance and control recommendations of the Federal Radiation Council; no control actions were suggested. Dietary intake of 90 Sr continued the general decline observed since 1961. Approximately 2600 test portions of imported foods were analyzed for contamination associated with the Chernobyl nuclear accident. Concentrations of radionuclide activity were below limits of detection for the vast majority of the imported food test portions but were above the levels of concern for 23 portions. Since 1986, the fraction of imported food test portions having measurable amounts of contamination has steadily declined, as have the average concentrations of radionuclide activity; however, contamination is still occasionally found. Continued monitoring of both domestic and imported foods is planned. 17 refs., 2 figs., 2 tabs

Modelling of radionuclide transport in forests: Review and future perspectives

International Nuclear Information System (INIS)

Shaw, G.; Schell, W.; Linkov, I.

1997-01-01

Ecological modeling is a powerful tool which can be used to synthesize information on the dynamic processes which occur in ecosystems. Models of radionuclide transport in forests were first constructed in the mid-1960's, when the consequences of global fallout from nuclear weapons tests and waste disposal in the environment were of great concern. Such models were developed based on site-specific experimental data and were designed to address local needs. These models had a limited applicability in evaluating distinct ecosystems and deposition scenarios. Given the scarcity of information, the same experimental data sets were often used both for model calibration and validation, an approach which clearly constitutes a methodological error. Even though the carry modeling attempts were far from being faultless, they established a useful conceptual approach in that they tried to capture general processes in ecosystems and thus had a holistic nature. Later, radioecological modeling attempted to reveal ecosystem properties by separating the component parts from the whole system, as an approach to simplification. This method worked well for radionuclide transport in agricultural ecosystems, in which the biogeochemistry of radionuclide cycling is relatively well understood and can be influenced by fertilization. Several models have been successfully developed and applied to human dose evaluation and emergency response to contaminating events in agricultural lands

Body-surface contamination monitoring preparatory to monitoring for internal contamination

International Nuclear Information System (INIS)

Schlueter, W.; Klucke, H.

1980-01-01

Measurements in the whole-body counter of the SAAS are routinely preceded by a thorough inspection of the patients for body-surface contamination to protect the sensitive counting equipment against becoming contaminated and to avoid a falsified indication of incorporated radionuclides. The measuring system employed for these examinations is described. (author)

Radionuclide distributions in phytocenoses elements of the Chernobyl' NPP 30-km zone

International Nuclear Information System (INIS)

Fedotov, I.S.; Mishenkov, N.N.; Arkhipov, N.P.

1989-01-01

In order to estimate the radioecological situation in phytocenoses of the 30-km zone consisting in the main of conifer and conifer-foliage forests, the studies, which give, an opportunity to divide the pine forests into five zones according to degrees of radiation injury character revealing, are made. These zones are characterized by total death, strong injury, intermediate injury, weak injury and stimulation. Radionuclides redistribution in the system including wood fier, forest litter and soil, their accumulation in organs and elements if each cenosis component are studied. The characteristics of experimental sections are given. The data on radionuclide distributions in soil profile of forest tracts, radionuclide concentrations in pine organs, radionuclide contents in mushrooms (conifers), contamination distribution (%) in pines under different levels of soil contamination are given. 6 tabs

Exposure-dose research for radionuclides in natural gas

International Nuclear Information System (INIS)

McNelis, D.N.; Patzer, R.G.

1969-01-01

The fate determination of specific radionuclides in natural gas stimulated by underground engineering applications is being examined. An experimental program, now in its initial stages, is using gas artificially labeled with krypton-85 and tritium under simulated domestic situations. The following topics are being investigated in this study: 1. The concentration of the radionuclides in a gas-heated home. 2. The build-up of contamination on appliances in the kitchen environment. 3. The concentration in foods as a function of radionuclide, food type and preparation. 4. The maximum exposure plausible under specified conditions. (author)

Biokinetics of radionuclides and treatment of accidental intakes

International Nuclear Information System (INIS)

Taylor, D.M.; Stradling, G.N.; Menetrier, F.

2003-01-01

This paper describes the objectives and reviews the progress of EULEP Working Party 5, convened under the auspices of the European Union's Fifth Framework Programme, to 'cluster' two EU-supported contracts, Biokinetics and Dosimetry of Internal Contamination (BIODOS (EU Contract FIS5-1999-00214)) and Radionuclide Biokinetics Database (EULEP) ( RBDATA-EULEP (Concerted Action Contract FIS5-1999-00218), and two non-EU funded projects, Biokinetics of Radionuclides in Human Volunteers (RNHV (non-EU Funded Project) and Treatment of Accidental Intakes of Radionuclides (TAIR (part-funded by EULEP)). (author)

Exposure-dose research for radionuclides in natural gas

Energy Technology Data Exchange (ETDEWEB)

McNelis, D N; Patzer, R G [Southwestern Radiological Health Laboratory, U.S. Public Health Service, Las Vegas, NV (United States)

1969-07-01

The fate determination of specific radionuclides in natural gas stimulated by underground engineering applications is being examined. An experimental program, now in its initial stages, is using gas artificially labeled with krypton-85 and tritium under simulated domestic situations. The following topics are being investigated in this study: 1. The concentration of the radionuclides in a gas-heated home. 2. The build-up of contamination on appliances in the kitchen environment. 3. The concentration in foods as a function of radionuclide, food type and preparation. 4. The maximum exposure plausible under specified conditions. (author)

Skin dose estimation due to a contamination by a radionuclide β emitter: are doses equivalent good estimator of protection quantities?

International Nuclear Information System (INIS)

Bourgois, L.

2011-01-01

When handling radioactive β emitters, measurements in terms of personal dose equivalents H p (0.07) are used to estimate the equivalent dose limit to skin or extremities given by regulations. First of all, analytical expressions for individual dose equivalents H p (0.07) and equivalent doses to the extremities H skin are given for a point source and for contamination with a radionuclide β emitter. Second of all, operational quantities and protection quantities are compared. It is shown that in this case the operational quantities significantly overstate the protection quantities. For a skin contamination the ratio between operational quantities and protection quantities is 2 for a maximum β energy of 3 MeV and 90 for a maximum β energy of 150 keV. (author)

Ferric iron remediation and stabilisation (firs) - developing a new robust electrokinetic remediation technique for heavy metal and radionuclide contaminated sites

International Nuclear Information System (INIS)

Faulkner, D.; Hopkinson, L.; Cundy, A.

2005-01-01

Electrokinetic remediation is an emerging technology that has generated considerable interest as a technique for the in-situ remediation of contaminated clay-rich soils and sediments. Despite promising experimental results, however, at present there is no standardised universal electrokinetic soil/sediment remediation approach. Many of the current technologies are technically complex and energy intensive, and geared towards the removal of 90% or more of specific contaminants, under very specific field or laboratory-based conditions. However, in the real environment a low-tech, low-energy contaminant reduction / containment technique may be more appropriate and realistic. Such a technique, FIRS (Ferric Iron Remediation and Stabilisation), is discussed here. The FIRS technique involves the application of a low magnitude (typically less than 0.2 V/cm) direct electric potential between two or more sacrificial, iron-rich, electrodes emplaced either side of a contaminated soil or sediment. The electric potential is used to generate a strong pH (and Eh) gradient within the soil column (pH 2 - 13), which acts to re-mobilize contaminants in the treated soil, and force the precipitation of an impermeable, sorptive iron-rich barrier or 'pan' in the soil between the electrodes. Geochemical data from bench-scale treatment cells indicate that the FIRS technique can significantly reduce the concentration of a range of heavy metals and radionuclides in contaminated soils, by remobilization of contaminants followed by precipitation on, or around, the iron-rich barrier generated by the technique. In addition, arsenic seems highly amenable to the FIRS treatment, due to its solubility under the high pH conditions generated near to the cathode, and its marked geochemical affinity with the freshly precipitated iron oxides and oxy-hydroxides in the iron barrier. Geotechnical tests indicate that the iron barrier produced by the technique is practically impervious (permeability 10 -9 m

Radionuclide behavior in the environment

International Nuclear Information System (INIS)

Tveten, U.

1991-09-01

The purpose of this report is to document the results of the following task: Review for quality and consistency the available data on measurements of initial ground contamination of Chernobyl radionuclides in various parts of Norway and subsequent concentrations of these radionuclides in various environmental media as functions of time. Utilize the data obtained to verify the existing models, or to improve them, for describing radionuclide behavior in the environment. Some of the processes standard were: migration into soil; weathering; resuspension; food-chain contamination; and loss or reconcentration by run-off. The task performed within this contract has been to use post-Chernobyl data from Norway to verify or find areas for possible improvement in the chronic exposure pathway models utilized in MACCS. Work has consisted mainly of collecting and evaluating post-Chernobyl information from Norway or other countries when relevant; but has also included experimental work performed specifically for the current task. In most connections the data available show the models and data in MACCS to be appropriate. A few areas where the data indicate that the MACCS approach is faulty or inadequate are, however, pointed out in the report. These should be examined carefully, and appropriate modifications should eventually be made. 14 refs., 12 figs., 22 tabs

Modeling Radionuclide Decay Chain Migration Using HYDROGEOCHEM

Science.gov (United States)

Lin, T. C.; Tsai, C. H.; Lai, K. H.; Chen, J. S.

2014-12-01

Nuclear technology has been employed for energy production for several decades. Although people receive many benefits from nuclear energy, there are inevitably environmental pollutions as well as human health threats posed by the radioactive materials releases from nuclear waste disposed in geological repositories or accidental releases of radionuclides from nuclear facilities. Theoretical studies have been undertaken to understand the transport of radionuclides in subsurface environments because that the radionuclide transport in groundwater is one of the main pathway in exposure scenarios for the intake of radionuclides. The radionuclide transport in groundwater can be predicted using analytical solution as well as numerical models. In this study, we simulate the transport of the radionuclide decay chain using HYDROGEOCHEM. The simulated results are verified against the analytical solution available in the literature. Excellent agreements between the numerical simulation and the analytical are observed for a wide spectrum of concentration. HYDROGECHEM is a useful tool assessing the ecological and environmental impact of the accidental radionuclide releases such as the Fukushima nuclear disaster where multiple radionuclides leaked through the reactor, subsequently contaminating the local groundwater and ocean seawater in the vicinity of the nuclear plant.

Consideration for modelling studies of migration of accidentally released radionuclides in a river watershed

International Nuclear Information System (INIS)

Matsunaga, Takeshi; Tsuduki, Katsunori; Yanase, Nobuyuki; Hanzawa, Yukiko; Ueno, Takashi

2004-01-01

Concerning radionuclides that might be released in an event of an accident from a nuclear facility, much attention has been paid to the migration pathways including the atmospheric deposition and subsequent inflow to surface water bodies since the Chernobyl nuclear accident in 1986. In European countries, computer-coded systems for predicting the migration including those pathways and providing scientific supports for decision makers to manage the contamination have been developed. This report is a summary of presentations and discussion made at the occasion of the visit of Dr. Monte in order to have directions related to the current subject of research, development of a mathematical model of the behavior of radionuclides in a river watershed. Those presentations and discussions were made at JAERI and also at prominent universities and institutes of Japan involved in this study field. As a result of these discussions, distinct advantages and key issues in use of a mathematical model for prediction of the migration of radionuclides in a river watershed have been identified and analyzed. It was confirmed that the use of mathematical modeling has distinct advantages. Re-arrangement of the existing experimental knowledge on the environment in an ordered way according to a theory (a mathematical model) will lead to a new angle to consider a problem in that environment, despite several gaps in the data array. A model to assess the radionuclide behaviour in contaminated aquatic ecosystems is a basis of decision analysis tools for helping decision-makers to select the most appropriate intervention strategies for the ecosystems. Practical use of a mathematical model and continuous effort in its validation were recognized as crucial. (author)

Estimated environmental radionuclide transfer and deposition into outdoor swimming pools

International Nuclear Information System (INIS)

Tagami, Kazumi; Nagata, Izumi; Sueki, Keisuke

2014-01-01

In 2011, a large radioactive discharge occurred at the Fukushima Daiichi nuclear power plant. This plant is located within a climatically temperate region where outdoor swimming pools are popular. Although it is relatively easy to decontaminate pools by refilling them with fresh water, it is difficult to maintain safe conditions given highly contaminated diurnal dust falls from the surrounding contaminated ground. Our objectives in this paper were to conduct daily radioactivity measurements, to determine the quantity of radioactive contaminants from the surrounding environment that invade outdoor pools, and to investigate the efficacy of traditional pool cleaners in removing radioactive contaminants. The depositions in the paper filterable particulates ranged from 0 to 62,5 Bq/m 2 /day, with the highest levels found in the southern Tohoku District containing Fukushima Prefecture and in the Kanto District containing Tokyo Metro. They were approximately correlated with the ground contamination. Traditional pool cleaners eliminated 99% of contaminants at the bottom of the pool, reducing the concentration to 41 Bq/m 2 after cleaning. Authors recommended the deposition or the blown radionuclides into outdoor swimming pools must be considered into pool regulations when the environments exactly polluted with radionuclides. - Highlights: • Deposition into outdoor swimming pool in a habitable areas estimated 72 Bq/m 2 /day. • More than 500 Bq/m 2 /day deposition will exceed our national guideline (10 Bq/l) of swimming pool. • Vacuum pool cleaner eliminates 99% radionuclides deposition

NARAC: an emergency response resource for predicting the atmospheric dispersion and assessing the consequences of airborne radionuclides

International Nuclear Information System (INIS)

Bradley, Michael M.

2007-01-01

The National Atmospheric Release Advisory Center (NARAC) serves as a national resource for the United States, providing tools and services to quickly predict the environmental contamination and health effects caused by airborne radionuclides, and to provide scientifically based guidance to emergency managers for the protection of human life. NARAC's scientists have developed a diverse tool kit of numerical modeling capabilities to respond to different types of release events, distance scales (local, regional, continental, and global), and response times

Peculiarities of radionuclide contamination of different Semipalatinsk nuclear test site (SNTS) zones

International Nuclear Information System (INIS)

Kadyrzhanov, K.K.; Khazhekber, S.; Lukashenko, S.N.; Solodukhin, V.P.; Kazachevskij, I.V.; Poznyak, V.L.; Knyazev, B.B.; Rofer, Ch.

2002-01-01

The Semipalatinsk Nuclear Test Site occupies about 18500 km 2 . There are 3 basic test zones in this territory including various test platforms where different character nuclear explosions were carried out. On the test platforms of the 'Opytnoe Pole' zone air and ground tests were performed, including nuclear and hydronuclear (without nuclear reaction) explosions. On the other zones (the Degelen mountains and Balapan valley) the underground tests including camouflaged and excavation nuclear explosions were carried out. Each kind of these tests can be characterised by the quantity and composition of radionuclides which were formed during the nuclear explosion, by the area of their distribution, localisation of the radionuclides at various sites, radionuclide species in soil. Transfer of the products of the air and the ground nuclear explosions by air flows and their sedimentation on the ground surfaces have caused broadband radioactive plumes extending over hundreds of kilometres. As a result of hydronuclear experiments, plenty of alpha-active radionuclides, consisting of a nuclear device is thrown locally out. Besides the ground and the air explosions, radiation conditions of the territory of the SNTS were influenced by excavation explosions with ground throwing out. Such tests resulted in an intensive local pollution. Other zone of an original pollution is the Degelen mountains. Although an basic mass of the nuclear explosion products is obviously concentrated in basin cavities of the tunnels, the radionuclides are taken out on a day time surface together with waters acting in the basin cavity of the tunnels. The results of investigation of radionuclide pollution on the various platforms of the SNTS territory are presented. The results characterise the radionuclide pollution by specificity of spent tests

Radionuclide characterization and associated dose from long-lived radionuclides in close-in fallout delivered to the marine environment at Bikini and Enewetak Atoll

International Nuclear Information System (INIS)

Noshkin, V. E.; Robison, W. L.

1998-01-01

Between June 1946 and October 1958, Enewetak and Bikini Atolls were used by the United States as testing grounds for 66 nuclear devices. The combined explosive yield from these tests was 107 Mt (Mt TNT equivalents). This testing produced close-in fallout debris that was contaminated with quantities of radioactive fission and particle activated products, and unspent radioactive nuclear fuel that entered the aquatic environment of the atolls. Today, the sediments in the lagoons are reservoirs for 10's of TBq of the transuranics and some long-lived fission and activation products. The larger amounts of contamination are associated with fine and coarse sediment material adjacent to the locations of the high yield explosions. Radionuclides are also distributed vertically in the sediment column to various depths in all regions of the lagoons. Concentrations greater than fallout background levels are found in filtered water sampled over several decades from all locations and depths in the lagoons. This is a direct indication that the radionuclides are continuously mobilized to solution from the solid phases. Of particular importance is the fact that the long-lived radionuclides are accumulated to different levels by indigenous aquatic plants and organisms that are used as food by resident people. One might anticipate finding continuous high contamination levels in many of the edible marine organisms from the lagoons, since the radionuclides associated with the sediments are not contained and are available to the different organisms in a relatively shallow water environment. This is not the case. We estimate that the radiological dose from consumption of the edible parts of marine foods at Enewetak and Bikini is presently about 0.05% of the total 50-year integral effective dose from all other exposure pathways that include ingestion of terrestrial foods and drinking water, external exposure and inhalation. The total radiological dose from the marine pathway is dominated by

Assessing potential impacts associated with contamination events in water distribution systems : a sensitivity analysis.

Energy Technology Data Exchange (ETDEWEB)

Davis, M. J.; Janke, R.; Taxon, T. N. (Decision and Information Sciences); ( EVS); (EPA)

2010-11-01

An understanding of the nature of the adverse effects that could be associated with contamination events in water distribution systems is necessary for carrying out vulnerability analyses and designing contamination warning systems. This study examines the adverse effects of contamination events using models for 12 actual water systems that serve populations ranging from about 104 to over 106 persons. The measure of adverse effects that we use is the number of people who are exposed to a contaminant above some dose level due to ingestion of contaminated tap water. For this study the number of such people defines the impact associated with an event. We consider a wide range of dose levels in order to accommodate a wide range of potential contaminants. For a particular contaminant, dose level can be related to a health effects level. For example, a dose level could correspond to the median lethal dose, i.e., the dose that would be fatal to 50% of the exposed population. Highly toxic contaminants may be associated with a particular response at a very low dose level, whereas contaminants with low toxicity may only be associated with the same response at a much higher dose level. This report focuses on the sensitivity of impacts to five factors that either define the nature of a contamination event or involve assumptions that are used in assessing exposure to the contaminant: (1) duration of contaminant injection, (2) time of contaminant injection, (3) quantity or mass of contaminant injected, (4) population distribution in the water distribution system, and (5) the ingestion pattern of the potentially exposed population. For each of these factors, the sensitivities of impacts to injection location and contaminant toxicity are also examined. For all the factors considered, sensitivity tends to increase with dose level (i.e., decreasing toxicity) of the contaminant, with considerable inter-network variability. With the exception of the population distribution (factor 4

The soil-to-plant transfer of radionuclides. Feasibilities and limits of the transfer concept

International Nuclear Information System (INIS)

Gerzabek, M.H.

1993-01-01

The present paper discusses the simple transfer model. After the Chernobyl fallout in Austria field investigations dealt with the behaviour of radionuclides in the soil-plant system. They led to the following conclusions: (1) A single plowing does not result in a homogeneous radionuclide distribution in the A p horizon. (2) Low plant availability of radionuclides (e.g. 137 Cs) led to a higher contribution of outer contamination (resuspension) to concentrations in plants in the first years after the fallout. Differences arose between high and low contamination areas. This was not true for 90 Sr, which exhibited three to ten times higher transfer factors as compared to 137 Cs. (3) The contamination source has a distinct impact on the plant availability of radionuclides. (4) In semi-natural environments radiocaesium can be bound to the biomass to a great extent, which results in significantly higher biological half-lives as compared to agricultural ecosystems. (author)

Determination of key radionuclides and parameters related to dose from the Columbia River pathway

International Nuclear Information System (INIS)

Napier, B.A.

1993-03-01

A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. These scoping calculations may include some radionuclides and pathways that were included in the Phase 1 Columbia River pathway dose evaluations, as well as other potential exposure pathways being evaluated for possible inclusion in future Hanford Environmental Dose Reconstruction Project (HEDR) modeling efforts. This scoping calculation (Calculation 009) examines the contributions of numerous radionuclides to dose via environmental exposures and accumulation in water, fish, and other aquatic biota. Addressed in these calculations are the contributions to effective dose from (1) external exposure to contaminated river water, ( 2) ingestion of contaminated drinking water, and (3) ingestion of contaminated resident Columbia River fish. Additional information on contamination of anadromous fish and waterfowl is provided

Rehabilitation of radioactive contaminated forests

International Nuclear Information System (INIS)

Panfilov, A.V.; Uspenskaya, E.Ju.

2002-01-01

As a result of radiation accidents and nuclear-weapon tests at the territory of the former USSR a part of the Forest Fund of 23 subjects of the Russian Federation has been contaminated by radionuclides. The contaminated forests, which are included in a structure of more than 130 forest management units (leskhozes) and more then 330 local forest management units, as a rule, are located in highly inhabited regions with traditionally intensive forestry management and high level of forest resources use. To provide radiologically safe forest management in the contaminated areas, the Federal Forest Service has developed and validated a special system of countermeasures. Use of this system makes it possible to diminish significantly the dose to personnel, to exclude the use of forest products with contamination exceeding radiological standards and to provide protection of the forest as a biogeochemical barrier to radionuclide migration from contaminated areas to human habitat. (author)

Adaptation and impairment of DNA repair function in pollen of Betula verrucosa and seeds of Oenothera biennis from differently radionuclide-contaminated sites of Chernobyl.

Science.gov (United States)

Boubriak, I I; Grodzinsky, D M; Polischuk, V P; Naumenko, V D; Gushcha, N P; Micheev, A N; McCready, S J; Osborne, D J

2008-01-01

The plants that have remained in the contaminated areas around Chernobyl since 1986 encapsulate the effects of radiation. Such plants are chronically exposed to radionuclides that they have accumulated internally as well as to alpha-, beta- and gamma-emitting radionuclides from external sources and from the soil. This radiation leads to genetic damage that can be countered by DNA repair systems. The objective of this study is to follow DNA repair and adaptation in haploid cells (birch pollen) and diploid cells (seed embryos of the evening primrose) from plants that have been growing in situ in different radionuclide fall-out sites in monitored regions surrounding the Chernobyl explosion of 1986. Radionuclide levels in soil were detected using gamma-spectroscopy and radiochemistry. DNA repair assays included measurement of unscheduled DNA synthesis, electrophoretic determination of single-strand DNA breaks and image analysis of rDNA repeats after repair intervals. Nucleosome levels were established using an ELISA kit. Birch pollen collected in 1987 failed to perform unscheduled DNA synthesis, but pollen at gamma/beta-emitter sites has now recovered this ability. At a site with high levels of combined alpha- and gamma/beta-emitters, pollen still exhibits hidden damage, as shown by reduced unscheduled DNA synthesis and failure to repair lesions in rDNA repeats properly. Evening primrose seed embryos generated on plants at the same gamma/beta-emitter sites now show an improved DNA repair capacity and ability to germinate under abiotic stresses (salinity and accelerated ageing). Again those from combined alpha- and gamma/beta-contaminated site do not show this improvement. Chronic irradiation at gamma/beta-emitter sites has provided opportunities for plant cells (both pollen and embryo cells) to adapt to ionizing irradiation and other environmental stresses. This may be explained by facilitation of DNA repair function.

Beta Autoradiography. An analytical technique to investigate radionuclides contamination on surface

International Nuclear Information System (INIS)

Ficher, P.; Goutelard, F.; Siitari-Kauppi, M.

2012-01-01

In decommissioning of old buildings and after disposal of nuclear facilities (materials, glove boxes,...), the inventory of the radioactive contamination of various building materials needs to be obtained in order to fix the working condition for dismantling. The challenge of this study was to classify different building materials of a whole research laboratory that was dedicated to research on organic molecules labeled with H-3 and C-14. The problem of waste classification is essential for safety treatment of waste and also for its cost. The analytical technique of beta autoradiography particularly well known for biological researches has been tested to investigate radionuclides contamination on surface. This technique is mainly interesting for beta and alpha emitters but also sensitive to gamma radiation. The first step of this technique is the deposit of a film on the surface of material to be analyzed. Films can be deposited on the ground or also fixed on the walls or even on the ceiling. The film is a plastic sheet covered with an emulsion containing photostimulable crystals and Eu that is activated when the film is exposed on radioactive source. The exposed films are then scanned with the Cyclone Plus equipment to get a digitized image. This image represents the radioactivity of the surface studied. The possibility to re-use the films is very important to investigate a large area. This autoradiography technique has retained our attention for its sensitivity and moreover the possibility of 2-dimensional investigation has been found as a real advantage. However it remains now as a qualitative technique and new studies must be launched to prove its quantitative potentialities. The high spatial resolution was not as important as in biological observation, and the mm resolution is totally sufficient

[The distribution of artificial radionuclides in the biomass of macrophytes of the Yenisei River].

Science.gov (United States)

Zotina, T A

2009-01-01

The Yenisei River is contaminated with artificial radionuclides due to the operation of the Mining-and-Chemical Combine (MCC), Rosatom, producing weapon grade plutonium for several decades. Artificial radionuclides including activation isotopes and transuranics, are detected in the biomass of submerged aquatic plants of the river. We investigated the distribution of artificial radionuclides in the biomass of macrophytes from radioactively contaminated part of the Yenisei River with chemical fractionation techniques. Artificial radionuclides were detected in extracellular and intracellular compartments of the macrophytes. The distribution of radionuclides among the biomass fractions differed essentially. 54Mn was preferably in mobile, exchangeable form compared to other isotopes. Essential portion of 137Cs was in non exchangeable form. Significant activity of artificial radionuclides was detected in the particles of suspended matter of the river, attached to the plant surfaces. Radioactive isotopes were distributed among biomass fractions similar to stable isotopes. The distribution of potassium and 137Cs differed essentially. On the basis of the results obtained the assumptions on the further migration of radionuclides accumulated by aquatic macrophytes in the Yenisei River have been done.

Effect of Concrete Waste Form Properties on Radionuclide Migration

International Nuclear Information System (INIS)

Mattigod, Shas V.; Bovaird, Chase C.; Wellman, Dawn M.; Skinner, De'Chauna J.; Cordova, Elsa A.; Wood, Marcus I.

2009-01-01

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation) the mechanism of contaminant release, the significance of contaminant release pathways, how waste form performance is affected by the full range of environmental conditions within the disposal facility, the process of waste form aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility, the effect of waste form aging on chemical, physical, and radiological properties and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the waste forms come in contact with groundwater. Numerous sets of tests were initiated in fiscal years (FY) 2006-2009 to evaluate (1) diffusion of iodine (I) and technetium (Tc) from concrete into uncontaminated soil after 1 and 2 years, (2) I and rhenium (Re) diffusion from contaminated soil into fractured concrete, (3) I and Re (set 1) and Tc (set 2) diffusion from fractured concrete into uncontaminated soil, (4) evaluate the moisture distribution profile within the sediment half-cell, (5) the reactivity and speciation of uranium (VI) (U(VI)) compounds in concrete porewaters, (6) the rate of dissolution of concrete monoliths, and (7) the diffusion of simulated tank waste into concrete.

Radionuclides in house dust

CERN Document Server

Fry, F A; Green, N; Hammond, D J

1985-01-01

Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, alt...

Feasibility study on application of bio-accumulation radionuclides as a countermeasure to restoration of contaminated environments

Energy Technology Data Exchange (ETDEWEB)

Watabe, Teruhisa; Hirano, Shigeki; Nakamura, Ryoichi [National Inst. of Radiological Sciences, Hitachinaka, Ibaraki (Japan). Lab. for Radioecology] [and others

2001-12-01

Phenomena of bio-accumulation of radionuclides was reviewed in order to know whether or not it was useful and effective to apply as a countermeasure to restoration of contaminated area, and to examine the extent of removal of radioactive contaminants from the environment. Special attention was directed to the technique, ''phytoremediation'' in which plants that hyperaccumulated heavy metals were cultivated on the contaminated lands for removing them. Plant species recognized as ''hyperaccumulator'' were searched in the literature and listed for providing a botanical and taxonomical prospect. On the other hand, a screening analysis was carried out for determining the elemental concentrations in sea weeds in order to find species with a high affinity for the specific elements. Of 30 species of sea weeds, the highest concentration of iron, iodine, strontium, and uranium was observed in Ulva sp., Laminaria sp., Corallina sp. and Undaria sp., respectively, although there were no species having the elemental concentration 100 times higher than those for so called ''reference plant''. Brown algae generally showed relatively higher concentrations for almost all elements of interest. It could be concluded that brown algae might be effective to use for phytoremediation because of their high affinity for many elements along with their high biomass in a possible case of radioactive contamination in the marine environment. Phytoremediation would be more advantageous not only from an economical viewpoint, but from the viewpoint of preservation of the environments than other possible remedial procedures, such as acid leaching of contaminants, excavation and storage of the soil, physical separation of the pollutants, and so on. This technique has been put into practical use and would gain much more support of the public in the future, however it needs more detailed information to establish as a sound and reliable

Feasibility study on application of bio-accumulation radionuclides as a countermeasure to restoration of contaminated environments

International Nuclear Information System (INIS)

Watabe, Teruhisa; Hirano, Shigeki; Nakamura, Ryoichi

2001-01-01

Phenomena of bio-accumulation of radionuclides was reviewed in order to know whether or not it was useful and effective to apply as a countermeasure to restoration of contaminated area, and to examine the extent of removal of radioactive contaminants from the environment. Special attention was directed to the technique, ''phytoremediation'' in which plants that hyperaccumulated heavy metals were cultivated on the contaminated lands for removing them. Plant species recognized as ''hyperaccumulator'' were searched in the literature and listed for providing a botanical and taxonomical prospect. On the other hand, a screening analysis was carried out for determining the elemental concentrations in sea weeds in order to find species with a high affinity for the specific elements. Of 30 species of sea weeds, the highest concentration of iron, iodine, strontium, and uranium was observed in Ulva sp., Laminaria sp., Corallina sp. and Undaria sp., respectively, although there were no species having the elemental concentration 100 times higher than those for so called ''reference plant''. Brown algae generally showed relatively higher concentrations for almost all elements of interest. It could be concluded that brown algae might be effective to use for phytoremediation because of their high affinity for many elements along with their high biomass in a possible case of radioactive contamination in the marine environment. Phytoremediation would be more advantageous not only from an economical viewpoint, but from the viewpoint of preservation of the environments than other possible remedial procedures, such as acid leaching of contaminants, excavation and storage of the soil, physical separation of the pollutants, and so on. This technique has been put into practical use and would gain much more support of the public in the future, however it needs more detailed information to establish as a sound and reliable methodology. (author)

Radionuclide containment in soil by phosphate treatment

International Nuclear Information System (INIS)

Lee, S.Y.; Francis, C.W.; Timpson, M.E.; Elless, M.P.

1995-01-01

Radionuclide transport from a contaminant source to groundwater and surface water is a common problem faced by most US Department of Energy (DOE) facilities. Containment of the radionuclide plume, including strontium-90 and uranium, is possible using phosphate treatment as a chemical stabilizer. Such a chemical process occurs in soils under natural environmental conditions. Therefore, the concept of phosphate amendment for radiostrontium and uranium immobilization is already a proven principle. In this presentation, results of bench-scale experiments and the concept of a field-scale demonstration are discussed. The phosphate treatment is possible at the source or near the advancing contaminant plume. Cleanup is still the ideal concept; however, containment through stabilization is a more practical and costeffective concept that should be examined by DOE Environmental Restoration programs

Calibration and verification of surface contamination meters --- Procedures and techniques

International Nuclear Information System (INIS)

Schuler, C; Butterweck, G.; Wernli, C.; Bochud, F.; Valley, J.-F.

2007-03-01

A standardised measurement procedure for surface contamination meters (SCM) is presented. The procedure aims at rendering surface contamination measurements to be simply and safely interpretable. Essential for the approach is the introduction and common use of the radionuclide specific quantity 'guideline value' specified in the Swiss Radiation Protection Ordinance as unit for the measurement of surface activity. The according radionuclide specific 'guideline value count rate' can be summarized as verification reference value for a group of radionuclides ('basis guideline value count rate'). The concept can be generalized for SCM of the same type or for SCM of different types using he same principle of detection. A SCM multi source calibration technique is applied for the determination of the instrument efficiency. Four different electron radiation energy regions, four different photon radiation energy regions and an alpha radiation energy region are represented by a set of calibration sources built according to ISO standard 8769-2. A guideline value count rate representing the activity per unit area of a surface contamination of one guideline value can be calculated for any radionuclide using instrument efficiency, radionuclide decay data, contamination source efficiency, guideline value averaging area (100 cm 2 ), and radionuclide specific guideline value. n this way, instrument responses for the evaluation of surface contaminations are obtained for radionuclides without available calibration sources as well as for short-Iived radionuclides, for which the continuous replacement of certified calibration sources can lead to unreasonable costs. SCM verification is based on surface emission rates of reference sources with an active area of 100 cm 2 . The verification for a given list of radionuclides is based on the radionuclide specific quantity guideline value count rate. Guideline value count rates for groups of radionuclides can be represented within the maximum

Radioactivity: radionuclides in foods

International Nuclear Information System (INIS)

Simpson, R.E.; Baratta, E.J.; Jelinek, C.F.

1977-01-01

The results are summarized of the analysis for strontium-90, cesium-137, iodine-131, ruthenium-106, and potassium-40, a naturally occurring radionuclide, in samples of total diet and selected import commodities in the foods compliance program of the Food and Drug Administration. On the basis of the radionuclide intake guidelines established by the Federal Radiation Council (FRC), the low content of radionuclides found in the total diet samples for fiscal years 1973 and 1974 demonstrates the need for surveillance only at the present level. The low levels of radionuclides found in a limited number of edible imported commodities indicate that their contribution to the total diet would not increase the levels of these radionuclides above those recommended for only periodic surveillance by the FRC. The potassium levels, determined from potassium-40 activity, found in meats and fish agree with the value for normal muscle tissue for the reference man reported by the International Commission on Radiation Protection. Of the other commodities, nuts contained the highest levels, while sugar, beverages, and processed foods contained the lowest levels of potassium. Although cesium and potassium are chemical analogs with similar metabolic properties, because of their variable content in some leafy samples as a result of surface contamination, a correlation between cesium-137 levels and the cesium-137-to-potassium ratio was inconclusive

Assessment of reproductive capacity of seeds sampled from natural populations of plants from a territory contaminated with radionuclides and heavy metals

Energy Technology Data Exchange (ETDEWEB)

Vakhusheva, O.; Evseeva, T. [Institute of biology Komi SC Ural Branch of RAS (Russian Federation)

2014-07-01

}=0.92, p<0.001) on soil radioactive contamination level and phosphates concentration. We suppose that mobile phosphates might reduce effects of radionuclide and metal toxicity on C. setosum and might facilitate formation of higher quality seeds. F. ulmariawas found to be the most resistant specie: no significant relationships were identified between radioactive and chemical contamination and the plant reproductive capacity. Germination of seeds sampled from contaminated sites was more than 3 times higher than values obtained for the reference site. The plant seed quality was found to be linearly dependent on soil organic matter content (R{sup 2}=0.88, p<0.0001). Thus, we observed that plant populations had different strategies of adaptation for living on soils contaminated with radionuclides and toxic metals. Moreover, the analyzed factors had a significant effect on the reproductive capacity of plants. Document available in abstract form only. (authors)

Radionuclides in sewage sludge and problems of use and disposal

International Nuclear Information System (INIS)

Schneider, P.; Tiefenbrunner, F.; Dierich, M.P.; Brunner, P.

1987-01-01

In a sewage plant with radioactive contaminated sewage an accumulation of radionuclide in the sewage sludge was to be found. The specific activities are in inverse proportion to the water content of the sewage sludge, the dehydrated sewage sludge shows the highest specific activities. These enriched radionuclides seem to be absorbed from the sludge. Yet they can be utilized by plants. This was demonstrated in experiments with Trifolium repens and Secale cereale, where the rate of absorption amounted 15-33% (inCi/kg dry weight plant:nCi/kg dry weight soil X 100) (transfer factors). This is why fertilization with radioactive contaminated sewage sludge seems to cause problems. In further experiments an extraction of radionuclides from ashed sewage sludge was shown. By acidifying the mobile phasis an increase in radioactivity in the eluated fractions was achieved. (orig./HP) [de

Point source attribution of ambient contamination events near unconventional oil and gas development.

Science.gov (United States)

Hildenbrand, Zacariah L; Mach, Phillip M; McBride, Ethan M; Dorreyatim, M Navid; Taylor, Josh T; Carlton, Doug D; Meik, Jesse M; Fontenot, Brian E; Wright, Kenneth C; Schug, Kevin A; Verbeck, Guido F

2016-12-15

We present an analysis of ambient benzene, toluene, and xylene isomers in the Eagle Ford shale region of southern Texas. In situ air quality measurements using membrane inlet mobile mass spectrometry revealed ambient benzene and toluene concentrations as high as 1000 and 5000 parts-per-billion, respectively, originating from specific sub-processes on unconventional oil and gas well pad sites. The detection of highly variant contamination events attributable to natural gas flaring units, condensate tanks, compressor units, and hydrogen sulfide scavengers indicates that mechanical inefficiencies, and not necessarily the inherent nature of the extraction process as a whole, result in the release of these compounds into the environment. This awareness of ongoing contamination events contributes to an enhanced knowledge of ambient volatile organic compounds on a regional scale. While these reconnaissance measurements on their own do not fully characterize the fluctuations of ambient BTEX concentrations that likely exist in the atmosphere of the Eagle Ford Shale region, they do suggest that contamination events from unconventional oil and gas development can be monitored, controlled, and reduced. Copyright © 2016 Elsevier B.V. All rights reserved.

Radionuclide sources in the Barents and Kara Seas

International Nuclear Information System (INIS)

Smith, J.N.; Ellis, K.M.; Forman, S.; Polyak, L.; Ivanov, G.; Matishov, D.; Kilius, L.

1995-01-01

A study of radionuclide distributions in the Barents Sea sediments was carried out in 1992. The conclusions of the study are as follows: 1) Elevated levels of artificial radionuclides as great as 15,000 Bq/kg for 239,240 Pu, 250 Bq/kg for 137 Cs and 100 Bq/kg for 60 Co were measured in sediments in Chermaya Bay which have been contaminated by several nuclear tests conducted in the 1950s. 2) Sediment-depth distributions of 239,240 Pu and other artificial radionuclides are consistent with results from biodiffusion models that are constrained by 210 Pb sediment-depth distributions. These results indicate that sedimentation rates in Chernaya Bay are low ( 249 Pu/ 239 Pu and 241 Pu/ 239 Pu atom ratios of 0.030 and 0.0012, respectively and a 241 Am/ 239,240 Pu activity ratio of 0.05 (compared to 0.3 in fallout) which provides a method for tracking its dispersion over distances of 100 km into the Barents Sea. 4) Artificial radionuclide levels in sediments and seawater near a sunken barge loaded with radioactive wastes in the Novaya Zemlya trough are similar to background fallout levels in the Kara Sea and provide little evidence for the release of radioactive contaminants from the dumpsite. 7 refs., 4 figs

RADIONUCLIDE INVENTORY AND DISTRIBUTION: FOURMILE BRANCH, PEN BRANCH, AND STEEL CREEK IOUS

Energy Technology Data Exchange (ETDEWEB)

Hiergesell, R.; Phifer, M.

2014-04-29

As a condition to the Department of Energy (DOE) Low Level Waste Disposal Federal Facility Review Group (LFRG) review team approving the Savannah River Site (SRS) Composite Analysis (CA), SRS agreed to follow up on a secondary issue, which consisted of the consolidation of several observations that the team concluded, when evaluated collectively, could potentially impact the integration of the CA results. This report addresses secondary issue observations 4 and 21, which identify the need to improve the CA sensitivity and uncertainty analysis specifically by improving the CA inventory and the estimate of its uncertainty. The purpose of the work described herein was to be responsive to these secondary issue observations by re-examining the radionuclide inventories of the Integrator Operable Units (IOUs), as documented in ERD 2001 and Hiergesell, et. al. 2008. The LFRG concern has been partially addressed already for the Lower Three Runs (LTR) IOU (Hiergesell and Phifer, 2012). The work described in this investigation is a continuation of the effort to address the LFRG concerns by re-examining the radionuclide inventories associated with Fourmile Branch (FMB) IOU, Pen Branch (PB) IOU and Steel Creek (SC) IOU. The overall approach to computing radionuclide inventories for each of the IOUs involved the following components: • Defining contaminated reaches of sediments along the IOU waterways • Identifying separate segments within each IOU waterway to evaluate individually • Computing the volume and mass of contaminated soil associated with each segment, or “compartment” • Obtaining the available and appropriate Sediment and Sediment/Soil analytical results associated with each IOU • Standardizing all radionuclide activity by decay-correcting all sample analytical results from sample date to the current point in time, • Computing representative concentrations for all radionuclides associated with each compartment in each of the IOUs • Computing the

Processes governing the transfer of radionuclides into crops following the Chernobyl accident

International Nuclear Information System (INIS)

Grebenshchikova, N.V.; Firsakova, S.K.; Timofeyev, S.F.; Novik, A.A.; Palekshanova, G.I.

1991-01-01

Given that the Chernobyl accident contaminated large areas of Byelorussia, we studied the processes governing - and the quantitative features of - radionuclide accumulation in meadow herbage and staple agricultural crops grown by farms in the Gomel Region. The fields are situated on soddy-podzolic sandy and sandy-loam soils where radiocaesium contamination varied between 15 and 80 Ci/km 2 . The quantitative features detected in radionuclide accumulation levels in crops (depending on soil composition and plant biological properties) confirmed the previously established basic mechanisms governing the transfer of radionuclides from soil to plants. Proportionality coefficients were determined for prediction purposes, and in 1987 these were (expressed in units of 10 -9 Ci/kg per Ci/km 2 ) 0.24 for grains of winter rye, 0.19 for barley and 0.65 for oats, 0.16 for potato tubers, 0.10 for beetroot and 0.23 for silage maize. These values were a factor of 4-5 lower in 1989. Depending on meadow type and soil properties, contamination levels in meadow herbage differed by up to two orders of magnitude. When the contaminated turf was reploughed or disc-harrowed and lime and potassium phosphate fertilizers added, contamination levels in the cultivated herbage fell by a factor of 4-7. (author)

Subsurface Contaminants Focus Area annual report 1997

International Nuclear Information System (INIS)

1997-01-01

In support of its vision for technological excellence, the Subsurface Contaminants Focus Area (SCFA) has identified three strategic goals. The three goals of the SCFA are: Contain and/or stabilize contamination sources that pose an imminent threat to surface and ground waters; Delineate DNAPL contamination in the subsurface and remediate DNAPL-contaminated soils and ground water; and Remove a full range of metal and radionuclide contamination in soils and ground water. To meet the challenges of remediating subsurface contaminants in soils and ground water, SCFA funded more than 40 technologies in fiscal year 1997. These technologies are grouped according to the following product lines: Dense Nonaqueous-Phase Liquids; Metals and Radionuclides; Source Term Containment; and Source Term Remediation. This report briefly describes the SCFA 1997 technologies and showcases a few key technologies in each product line

Characterization of calculation of in-situ retardation factors of contaminant transport using naturally-radionuclides and rock/water interaction occurring U-Series disequilibria timescales. 1997 annual progress report

International Nuclear Information System (INIS)

Goldstein, S.; Ku, T.L.; Luo, S.; Murrel, M.; Roback, R.

1997-01-01

'The research is directed toward a quantitative assessment of contaminant transport rates in fracture-rock systems using uranium-series radionuclides. Naturally occurring uranium-and thorium-series radioactive disequilibria will provide information on the rates of adsorption-desorption and transport of radioactive contaminants as well as on fluid transport and rock dissolution in a natural setting. This study will also provide an improved characterization of preferential flow and contaminant transport at the Idaho Environmental and Engineering Lab. (INEEL) site. To a lesser extent, the study will include rocks in the unsaturated zone. The authors will produce a realistic model of radionuclide migration under unsaturated and saturated field conditions at the INEEL site, taking into account the retardation processes involved in the rock/water interaction. The major tasks are to (1) determine the natural distribution of U, Th, Pa and Ra isotopes in rock minerals. sorbed phases on the rocks, and in fluids from both saturated and unsaturated zones at the site, and (2) study rock/water interaction processes using U/Th series disequilibrium and a statistical analysis-based model for the Geologic heterogeneity plays an important role in transporting contaminants in fractured rocks. Preferential flow paths in the fractured rocks act as a major pathway for transport of radioactive contaminants in groundwaters. The weathering/dissolution of rock by groundwater also influences contaminant mobility. Thus, it is important to understand the hydrogeologic features of the site and their impact on the migration of radioactive contaminants. In this regard, quantification of the rock weathering/dissolution rate and fluid residence time from the observed decay-series disequilibria will be valuable. By mapping the spatial distribution of the residence time of groundwater in fractured rocks, the subsurface preferential flow paths (with high rock permeability and short fluid residence

Unclassified Source Term and Radionuclide Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0

Energy Technology Data Exchange (ETDEWEB)

McCord, John

2004-08-01

This report documents the evaluation of the information and data available on the unclassified source term and radionuclide contamination for Central and Western Pahute Mesa: Corrective Action Units (CAUs) 101 and 102.

Possibilities of using Eisenia Andrei earthworms as bioindicators of radioactive soil contamination

International Nuclear Information System (INIS)

Galanda, D.; Strisovska, J.; Lacenova, A.

2017-01-01

Eisenia Andrei is known under various generic names such as Californian daisy, red daisy, tiger worm etc. It is a species of earthworm that is physiologically adapted to life in a medium containing organic matter. Staining (vermiremedia technology) of soils contaminated with heavy metals belongs among innovative and efficient techniques. According to published works, this technology is easy to apply. Dandelions are used for soil rehabilitation, rejuvenation and mineral enrichment in the soil. In the soil environment, the effect of the sunsets is known as the drilosphere of the system, that is, the soil is under their direct influence. The aim of the present paper was to verify the possibility of application and subsequent use of Eisenia Andrei sunflowers as bioindicators in soil contaminated by radionuclides "2"3"9Pu and "2"4"1Am, which are significant anthropogenic radionuclides emitting alpha particles. Another circle of radionuclides were anthropogenic radionuclides "6"0Co and "1"3"7Cs emitting gamma rays. Based on the radionuclides used, two groups of target-contaminated samples were subjected to experimentation and spectrometric analysis alone. The first group of experimental subjects was made up of earthworms living in alpha radionuclide-enriched soils, and in the second group of gamma-radionuclides. Radiochemical analysis of alpha radionuclides was performed by a separation method of extraction chromatography using commercial sorbents from Triskem-TEVA Resin and DGA Resin. The preparation of specimens for the spectroscopic analysis of the emitted alpha configuration was performed by co-precipitation with NdCl_3. The measurement itself was performed with the ORTEC 576A Alpha Spectrometer with the GammaVision software. The activity of gamma radionuclides in a sample of animals devoid of possible surface contamination from the nutrient medium of the contaminated soil was measured using the Ortec gamma spectrometer. (authors)

Species diversity of plant communities from territories with natural origin radionuclides contamination

Energy Technology Data Exchange (ETDEWEB)

Kaneva, A.V.; Belykh, E.S.; Maystrenko, T.A.; Grusdev, B.I.; Zainullin, V.G.; Vakhrusheva, O.M. [Institute of Biology, Komi Scientific Center, Ural Division of RAS, Syktyvkar, 167982 (Russian Federation); Oughton, D. [Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Aas (Norway)

2014-07-01

Since plants dominate every landscape, the impact of any environmental stressor on plants can directly affect the structure and function of an ecosystem, resulting in decreased primary productivity and degradation of wildlife habitat. The investigation goal of the present research was to study how vascular plant species' composition at a former radium mining site could be related to i) soil contamination with heavy metals and uranium and thorium decay chain radionuclides and ii) soil agrochemical properties. Between the 1930's and 1950's, the commercial extraction of radium, storage of the uranium mill tailings and radium production wastes, together with deactivation of the site with a mixture of sand and gravel completely destroyed plant communities in the vicinity of Vodny settlement (Komi Republic, Russia). The plant cover recovery started more than 60 years ago, and resulted in overgrowing with common grassland plant species. Three meadow sites were investigated, one with low contamination (on the territory of former radium production plant), one with high contamination (waste storage cell) and a reference sites out of the radiochemical plant zone of influence, but with similar natural conditions. Geo-botanical descriptions revealed 134 vascular plant species from 34 families in the meadow communities studied. The greatest richness was seen for Poaceae, Asteraceae, Rosaceae and Fabaceae families; others had 1-5 species. The highest richness in diversity was seen at reference sites with 95 vascular plant species. 87 species were registered on low contaminated sites and 75 species on high contaminated. Perennial herbs were the dominant life form on all the studied meadow communities. Arboreal species expansion in vegetation was noted at both experimental and reference sites. Shannon index calculations indicated a significant (p<0.05) decrease in species diversity on sample areas of the highly contaminated radioactive waste storage cell. Mean values

Stochastic analysis of contaminant transport in porous media: analysis of a two-member radionuclide chain

International Nuclear Information System (INIS)

Bonano, E.J.; Shipers, L.R.

1987-01-01

In this study the authors extend previous stochastic analyses of contaminant transport in geologic media for a single species to a chain of two species. The authors particular application is the quantification of uncertainties due to lack of characterization of the spatial variability of hydrologic parameters on transport of radionuclides from a high-level waste repository to the biosphere. Radionuclide chains can have a significant impact on demonstrating compliance (or violation) of standards regulating the release to the environment accessible to humans. Two approaches for determining the cross-covariance terms in the mean concentration equations are presented. One uses a Taylor expansion to obtain the cross-covariance between the velocity and concentration fluctuations, while the other is based on a Fourier-Laplace double transform method. For the conditions of interest here, the difference between these two approaches are expected to be small. In addition, the variances are calculated in a unique way by solving another associated partial differential equation. A parametric study is carried out to examine the sensitivity of the mean concentration of the two species and their corresponding variances and cross-covariance on the parameters associated with the structure of the stochastic velocity field. It is found that the dependent variables are most sensitive to the intensity and correlation length of the velocity fluctuations. The magnitude of the variances and cross-covariance of the concentrations are proportional to the magnitude of the mean concentrations which depend on inlet concentration boundary conditions

Migration of heavy natural radionuclides in a humid climatic zone

International Nuclear Information System (INIS)

Titaeva, N.A.; Alexakhin, R.M.; Taskaev, A.I.; Maslov, V.I.

1980-01-01

Regularities and biochemical peculiarities of the migrations of heavy natural radionuclides in the environment are examined, with special reference to two regions in a humid climatic zone representing natural patterns of radionuclide distribution and to four plots artificially contaminated with high levels of natural radioactivity more than 20 years previously. It was determined that the migration of thorium, uranium, and radium isotopes through the rock-water-soil-plant system is dependent on many physiochemical properties of these radionuclides, their compounds, and the local environment. Isotopic activity ratios provide a useful tool for studying the direction of radionuclide migration and its influence on observed distribution patterns

Chemical fractionation of radionuclides and stable elements in aquatic plants of the Yenisei River.

Science.gov (United States)

Bolsunovsky, Alexander

2011-09-01

The Yenisei River is contaminated with artificial radionuclides released by one of the Russian nuclear plants. The aquatic plants growing in the radioactively contaminated parts of the river contain artificial radionuclides. The aim of the study was to investigate accumulation of artificial radionuclides and stable elements by submerged plants of the Yenisei River and estimate the strength of their binding to plant biomass by using a new sequential extraction scheme. The aquatic plants sampled were: Potamogeton lucens, Fontinalis antipyretica, and Batrachium kauffmanii. Gamma-spectrometric analysis of the samples of aquatic plants has revealed more than 20 radionuclides. We also investigated the chemical fractionation of radionuclides and stable elements in the biomass and rated radionuclides and stable elements based on their distribution in biomass. The greatest number of radionuclides strongly bound to biomass cell structures was found for Potamogeton lucens and the smallest for Batrachium kauffmanii. For Fontinalis antipyretica, the number of distribution patterns that were similar for both radioactive isotopes and their stable counterparts was greater than for the other studied species. The transuranic elements (239)Np and (241)Am were found in the intracellular fraction of the biomass, and this suggested their active accumulation by the plants.

Methodological guide for risk assessment and management of industrial sites contaminated with radionuclides

International Nuclear Information System (INIS)

Oudiz, A.; Brenot, J.; Cessac, B.; Charbonneau, P.; Maigne, J.P.; Santucci, P.

2000-01-01

At the request of the French ministries of health and environment, IPSN was asked to elaborate a methodological guide for risk assessment and management of industrial sites contaminated with radionuclides. This guide is devoted to local administration, technical organisms and more generally to all the relevant stakeholders involved with the choice of a rehabilitation strategy, according to the future use of the site. The methodology to be presented is designed to fit with the different types of 'risk governance', according to circumstances: - when an industrial site is relatively small, with rather restricted zones of contamination, and no specific social concern, management may rely essentially upon radiological expertise, using generic reference levels, - when the site is larger, with spread out contamination, risk assessment and management of the site may become more controversial, namely because uncertainties remain about the effective magnitude of the contamination and no low cost solution appears to exist in view of rehabilitation. In this case, an open procedure is required, which combines technical expertise and involvement of stakeholders, in view of improving the risk assessment process as well as trying to get a better understanding of the benefits and drawbacks of different rehabilitation strategies. The methodology consists of six main steps : - Initiating the process, Pre-diagnosis, Initial diagnosis, Simplified risk assessment, Detailed risk assessment, Decision aiding in view of letting the stakeholders defining the solution appropriate to the local context. The paper will present how the risk assessment and management process can be aportionated to the importance of the problem to be solved. As far as possible, simplified risk assessment should provide information allowing the definition of the appropriate strategy. In this case, stakeholders involvement is mainly devoted to determine: - whether the site can be affected to a given use without

Radionuclide characterization and associated dose from long-lived radionuclides in close-in fallout delivered to the marine environment at Bikini and Enewetak Atolls

International Nuclear Information System (INIS)

Robison, W.L.; Noshkin, V.E.

1999-01-01

Between June 1946 and October 1958, Enewetak and Bikini Atolls were used by the US as testing grounds for 66 nuclear devices. The combined explosive yield from these tests was 107 million t (million t TNT equivalents). This testing produced close-in fallout debris that was contaminated with quantities of radioactive fission and particle activated products, and unspent radioactive nuclear fuel that entered the aquatic environment of the atolls. Today, the sediments in the lagoons are reservoirs for tens of TBq of the transuranics and some long-lived fission and activation products. The larger amounts of contamination are associated with fine and coarse sediment material adjacent to the locations of the high yield explosions. Radionuclides are also distributed vertically in the sediment column to various depths in all regions of the lagoons. Concentrations greater than fallout background levels are found in filtered water sampled over several decades from all locations and depths in the lagoons. This is a direct indication that the radionuclides are continuously mobilized to solution from the solid phases. Of particular importance is the fact that the long-lived radionuclides are accumulated to different levels by indigenous aquatic plants and organisms that are used as food by resident people. One might anticipate finding continuous high contamination levels in many of the edible marine organisms from the lagoons, since the radionuclides associated with the sediments are not contained and are available to the different organisms in a relatively shallow water environment. This is not the case. We estimate that the radiological dose from consumption of the edible parts of marine foods at Enewetak and Bikini is presently approximately 0.05% of the total 50-year integral effective dose from all other exposure pathways that include ingestion of terrestrial foods and drinking water, external exposure and inhalation. The total radiological dose from the marine pathway is

Colloid-Facilitated Transport of Radionuclides Through The Vadose Zone

International Nuclear Information System (INIS)

Markus Flury; James B. Harsh; John F. McCarthy' Peter C. Lichtner; John M. Zachara

2007-01-01

The main purpose of this project was to advance the basic scientific understanding of colloid and colloid-facilitated Cs transport of radionuclides in the vadose zone. We focused our research on the hydrological and geochemical conditions beneath the leaking waste tanks at the USDOE Hanford reservation. Specific objectives were (1) to determine the lability and thermodynamic stability of colloidal materials, which form after reacting Hanford sediments with simulated Hanford Tank Waste, (2) to characterize the interactions between colloidal particles and contaminants, i.e., Cs and Eu, (3) to determine the potential of Hanford sediments for in situ mobilization of colloids, (4) to evaluate colloid-facilitated radionuclide transport through sediments under unsaturated flow, (5) to implement colloid-facilitated contaminant transport mechanisms into a transport model, and (6) to improve conceptual characterization of colloid-contaminant-soil interactions and colloid-facilitated transport for clean-up procedures and long-term risk assessment

Transfer of Chernobyl radionuclides in the aquatic systems

International Nuclear Information System (INIS)

Zhukova, O.; Shiryaeva, N.; Shagalova, E.; Bakarykava, Zh.

2003-01-01

The data on radioecology of the rivers of Belarus, which catchment area is completely or partly situated in Russia and the Ukraine (the Sozh, the Iput, the Besed, the Braginka) are given. The radioactive contamination of lakes are represent. The article demonstrates, that nowadays Chernobyl radionuclides content in surface water depends on wash-off from contaminated territories, groundwater leakage, and composition of bottom sediments. Wash out by rain and melted water is considered to be the most permanent and hazardous. The accumulation of radioactive sediments before dams, in stagnant zones of rivers and reservoirs creates moving local cites of increased concentration. Today and for forthcoming decades the main input into water contamination will be Cs-137, Sr-90 and for the nearest Chernobyl PP zone - isotopes of plutonium as well as Am-241. The migration of radionuclides on the experimental watershed of the Iput river was investigated. The studies have shown that the contamination of the Iput river in the territory of Belarus was influenced by the transboundary transfer of radionuclides from the territory of Russia during first years after Chernobyl accident. According to our estimates, at the end of 1986, this contribution amounted to 30% for Cs-137 and 96% for Sr-90; as of-now, it is 86% and 65% for Cs-137 and Sr-90, respectively. The concentration of Cs-137 in bottom sediments on some sites in the Braginka river (12940 - 49760 Bq/kg), the Revuchee lake (10345 - 18260 Bq/kg) and the Svyatskoe lake (11618 - 16430 Bq/kg) are so great, that they can be attributed to low-level waste storage facilities (9630 Bq/kg). Such high levels of radioactive contamination of bottom sediments are secondary sources of pollution of surface water. (authors)

Extrapolation of experimental data on late effects of low-dose radionuclides in man

International Nuclear Information System (INIS)

Kalistratova, V.S.; Nisimov, P.G.

1997-01-01

The situation of living of population on radionuclide contamination areas was simulated in the experimental study using white strainless rats of different ages. The significance of age for late stochastic effects of internal radionuclide contamination with low doses of 131 I, 137 Cs, 144 Ce and 106 Ru was studied. Some common regularities and differences in late effects formation depending on age were found. Results of the study showed that the number of tumors developed increased in groups of animals exposed at the youngest age. The younger animal at the moment of internal radionuclide contamination, the higher percentage of malignant tumors appeared. It was especially so for tumors of endocrine glands (pituitary, suprarenal,- and thyroid). Differences in late effects formation related to different type of radionuclide distribution within the body were estimated. On the base of extrapolation the conclusion was made that human organism being exposed at early postnatal or pubertal period could be the most radiosensitive (1.5-2.0 or sometimes even 3-5 times higher than adults). Data confirmed the opinion that children are the most critical part of population even in case of low dose radiation exposure. (author)

Removal of contaminated asphalt layers by using heat generating powder metallic systems

International Nuclear Information System (INIS)

Barinov, A.S.; Karlina, O.K.; Ojovan, M.I.

1996-01-01

Heat generating systems on the base of powder metallic fuel were used for the removal of contaminated asphalt layers. Decontamination of spots which had complex geometric form was performed. Asphalt layers with deep contamination were removed essentially all radionuclides being retained in asphalt residue. Only a small part (1 - 2 %) of radionuclides could pass to combustion slag. No radionuclides were detected in aerosol-gas phase during decontamination process

Using on based molecular biology approaches to assess plant elusive responses mechanisms to chronic ionizing radiation in radionuclide contaminated Chernobyl zone

International Nuclear Information System (INIS)

Rashydov, N.; Hajduch, M.

2014-01-01

Full text : It is well known that the Chernobyl accident released large amounts of radioactive isotopes into the environment. As a consequence, the vicinity of Chernobyl Nuclear power Plant remains contaminated with long-lived radionuclide such as 137Cs, 90Sr and several transuranic isotopes. There have been a few molecular analyses of plants grown in the radio-contaminated Chernobyl area, but there is as yet no broad understanding of the mechanisms that underlie their survival or success. Much research has addressed the nature of mutation sites in DNA, changes in signaling networks, epigenetic changes, changes at the transcription level, protein level. All of these must be considered when designing a global strategy for understanding the far discovering elusive of resistance and adaptive mechanisms of plants to chronic ionizing radiation

Radionuclides in air, water, and biota

International Nuclear Information System (INIS)

Seymour, A.H.; Nelson, V.A.

1977-01-01

Air, water, and biological samples collected before and after the 1965, 1969, and 1971 underground nuclear detonations at Amchitka Island were analyzed for natural and fallout radionuclides by gamma spectrometry. Selected samples were also analyzed for tritium, 55 Fe, and 90 Sr. The objectives were to search for and identify radionuclides of Amchitka origin in the samples and to contribute to the general knowledge of the distribution of radionuclides in the environment. The studies showed that there has been no escape of radionuclides from the underground sites of the three nuclear detonations at Amchitka Island except for trace quantities of radionuclides, principally tritium, in water and soil gas samples from the immediate vicinity of the surface ground zero for the 1965 event. Two naturally occurring radionuclides, 40 K and 7 Be, were the most abundant radionuclides in the samples, usually by a factor of 10 or more, except for 137 Cs in lichen samples. All levels were well below applicable Radiation Protction Guides, often being near the statistical limit of detection

Evaluation of data on the transfer of radionuclides in the food chain post-Chernobyl action

International Nuclear Information System (INIS)

Desmet, G.; Sinnaeve, J.

1992-01-01

During the accident at Chernobyl large amounts of radioactive materials were released into the atmosphere and distributed all over Europe. Depending on the trajectories of the radioactive clouds and the large variation of rainfall during its passage through, large local and regional differences in deposition were observed, leading to an enhanced contamination of soil and plants. Consequently, the radionuclides entered the foodchain by several pathways. The radiological consequences of radionuclides discharged from nuclear installations usually are evaluated using doses assessment models. In these models the passage from one compartment into another, e.g. the transfer from soil into plants, from plants into milk or meat is defined by transfer factors, which are influenced by various parameters. From the long term point of view only the long-lived nuclides like 134/137 Cs are important for long term radiation risk assessment after the Chernobyl accident. In this accident the release of radioactive materials took place over a longer time period and varied in rate and radionuclide composition. Some regions of Europe were contaminated several times. To improve radiation dose prediction the CEC has initiated the Post-Chernobyl radiation protection programme 'Evaluation of Data on the Transfer of Radionuclides in the Foodchain' including five main items to be studied by different laboratories: 1. Impact of chemical speciation on the radionuclide transfer in terrestrial ecosystems after a core disruptive accident, especially in soils and plants. 2. Transfer paths of radionuclides in seminatural and natural ecosystems and their role in contaminating the foodchain. 3. Validation of soil-to-plant parameters. 4. Transfer of radionuclides to animals and animal products. 5. Transfer paths in aquatic systems and their importance for the contamination of the foodchain

137Cs absorption factors (AFs) from contaminated cooking water to some vegetable and protein samples

International Nuclear Information System (INIS)

Malek, M.A.

2006-01-01

The radionuclide in contaminated freshwater may directly gain access to the human body through two major routes: drinking and cooking food with fresh water. During cooking, the radionuclide present in the water may be transferred to the various ingredients of the cooked food. The degree of contamination of food during cooking depends both on absorption power of the individual ingredients and the level of radionuclide present in the water. The ratio of the concentration of the radionuclide absorbed in the individual ingredients to the concentration in the cooking water can be designated as 'Absorption factor' (AF). AF can be used to predict the radionuclide absorbed by the ingredients cooked with contaminated water, to assess the internal radiation dose to the consumer and radionuclide transfer from the cooking water to the ingredients. A better understanding of the variables that affect the AF in various ingredients during cooking is central to deriving the contamination level of the ingredients. 10 kinds of greens and vegetable and 3 kinds of animal protein were boiled with 37 Cs contaminated freshwater and corresponding AFs were determined in both hot and cooled condition

Wide Area Recovery and Resiliency Program (WARRP) Interim Clearance Strategy for Environments Contaminated with Hazardous Chemicals

Science.gov (United States)

2012-07-01

imperative that the community address the range of values, and have agreement, before a disaster strikes. Pre-event clearance level concurrence is...on the cleanup of specific sites: those containing only cesium-137 (Goiania) and those containing 137Cs and other radionuclides ( Chernobyl ...targets and consider initiatives to enhance the quality of life of the residents of the contaminated areas. Recovery experience from the Chernobyl

Radioactive contamination of the Balchug (Upper Yenisey) floodplain, Russia in relation to sedimentation processes and geomorphology.

Science.gov (United States)

Linnik, V G; Brown, J E; Dowdall, M; Potapov, V N; Surkov, V V; Korobova, E M; Volosov, A G; Vakulovsky, S M; Tertyshnik, E G

2005-03-01

The radioactive contamination of a riverine floodplain, heavily influenced by discharges from Krasnoyarsk-26, has been studied with respect to sedimentation processes and the geomorphology of the Upper Yenisey floodplain. The study was effected by implementation of a regime of in situ observations and measurements, sampling, and the interpretation of satellite images. The results of the study indicate that on the Balchug Bypass Floodplain, radionuclide contamination is primarily influenced by the thickness of the deposited sediments, and the area can be considered as two depositional environments. The Balchug floodplain area was contaminated due to sedimentation of radionuclide-contaminated alluvium, whose depositional regime significantly changed after the construction of a hydroelectric power station in 1967. Contamination levels are lower on the upstream part of the floodplain where sediment depth is less than 0.2-0.3 m, and this contamination started to accumulate in 1967, while the downstream part of the floodplain, exhibiting deeper deposits, displays higher levels of radionuclide contamination because radionuclides began to deposit here in 1958 when the Krasnoyarsk-26 Mining and Chemical Combine (KMCC) commenced operation. Radionuclide contamination of the floodplain is also related to the elevation of the floodplain, higher regions of the floodplain typically having lower contamination than low-lying areas, which tend to be frequently inundated with sediments being deposited during such inundations. Local relief, its orientation, and vegetation cover have also combined to form sediment traps with significantly higher radionuclide contamination. Lithological analysis combined with radiometric assay indicates a total 137Cs floodplain inventory of 33.7 GBq.

Radioactive contamination of the Balchug (Upper Yenisey) floodplain, Russia, in relation to sedimentation processes and geomorphology

International Nuclear Information System (INIS)

Linnik, V.G.; Korobova, E.M.; Volosov, A.G.; Brown, J.E.; Dowdall, M.; Potapov, V.N.; Surkov, V.V.; Vakulovsky, S.M.; Tertyshnik, E.G.

2005-01-01

The radioactive contamination of a riverine floodplain, heavily influenced by discharges from Krasnoyarsk-26, has been studied with respect to sedimentation processes and the geomorphology of the Upper Yenisey floodplain. The study was effected by implementation of a regime of in situ observations and measurements, sampling, and the interpretation of satellite images. The results of the study indicate that on the Balchug Bypass Floodplain, radionuclide contamination is primarily influenced by the thickness of the deposited sediments, and the area can be considered as two depositional environments. The Balchug floodplain area was contaminated due to sedimentation of radionuclide-contaminated alluvium, whose depositional regime significantly changed after the construction of a hydroelectric power station in 1967. Contamination levels are lower on the upstream part of the floodplain where sediment depth is less than 0.2-0.3 m, and this contamination started to accumulate in 1967, while the downstream part of the floodplain, exhibiting deeper deposits, displays higher levels of radionuclide contamination because radionuclides began to deposit here in 1958 when the Krasnoyarsk-26 Mining and Chemical Combine (KMCC) commenced operation. Radionuclide contamination of the floodplain is also related to the elevation of the floodplain, higher regions of the floodplain typically having lower contamination than low-lying areas, which tend to be frequently inundated with sediments being deposited during such inundations. Local relief, its orientation, and vegetation cover have also combined to form sediment traps with significantly higher radionuclide contamination. Lithological analysis combined with radiometric assay indicates a total 137 Cs floodplain inventory of 33.7 GBq

Radionuclide contaminant analysis of small mammals at Area G, Technical Area 54, 1996 (with cumulative summary for 1994--1996)

International Nuclear Information System (INIS)

Biggs, J.R.; Bennett, K.D.; Fresquez, P.R.

1997-07-01

Small mammals were sampled at two waste burial sites at Area G, Technical Area (TA) 54 and a control site within the proposed Area G expansion area in 1996 to (1) identify radionuclides that are present within rodent tissues at waste burial sites, (2) to compare the amount of radionuclide uptake by small mammals at waste burial sites to a control site, and (3) to identify the primary mode of contamination to small mammals, either through surface contact or ingestion/inhalation. Three composite samples of approximately five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. Samples were analyzed for 241 Am, 90 Sr, 238 Pu, 239 Pu, total U, 137 Cs, and 3 H. Higher levels of total U, 241 Am, 238 Pu, and 239 Pu were detected in pelts as compared to the carcasses of small mammals at TA-54. Concentrations of other measured radionuclides in carcasses were nearly equal to or exceeded the mean concentrations in the pelts. Due to low sample sizes in total number of animals captured, statistical analysis to compare site to site could not be conducted. However, mean concentrations of total U, 238 Pu, 239 Pu, and 137 Cs in rodent carcasses were higher at Site 1 than site 2 or the Control Site and 241 Am was higher at Site 2 than Site 1 or the Control Site

Radionuclide migration in soil within the estrangement zone of ChNPP

International Nuclear Information System (INIS)

Mikhalkin, G.S.; Arkhipov, A.N.; Arkhipov, N.P.; Sukhoruchkin, A.K.

1992-01-01

The problems of the radionuclide migration and redistribution in soil within the estrangement zone of ChNPP have been discussed. It has been demonstrated that the surface radioactive contamination of soil that has been represented principally by the particles of the waste nuclear fuel eventually migrates into soil depth. In this case the radionuclides remain principally the fuel matrix components, the fuel matrix decomposing gradually and releasing the radionuclides. The mechanisms of the radionuclide migration can be described with the quasi-diffusion migration model in most cases. On the 5th year since the accident the major portion of the radionuclides (95-99%) is still kept within 0-5 cm layer of soil. 3 figs.; 7 tabs

Development of emergency response tools for accidental radiological contamination of French coastal areas

International Nuclear Information System (INIS)

Duffa, Céline; Bailly du Bois, Pascal; Caillaud, Matthieu; Charmasson, Sabine; Couvez, Céline; Didier, Damien; Dumas, Franck; Fievet, Bruno; Morillon, Mehdi; Renaud, Philippe

2016-01-01

The Fukushima nuclear accident resulted in the largest ever accidental release of artificial radionuclides in coastal waters. This accident has shown the importance of marine assessment capabilities for emergency response and the need to develop tools for adequately predicting the evolution and potential impact of radioactive releases to the marine environment. The French Institute for Radiological Protection and Nuclear Safety (IRSN) equips its emergency response centre with operational tools to assist experts and decision makers in the event of accidental atmospheric releases and contamination of the terrestrial environment. The on-going project aims to develop tools for the management of marine contamination events in French coastal areas. This should allow us to evaluate and anticipate post-accident conditions, including potential contamination sites, contamination levels and potential consequences. In order to achieve this goal, two complementary tools are developed: site-specific marine data sheets and a dedicated simulation tool (STERNE, Simulation du Transport et du transfert d’Eléments Radioactifs dans l'environNEment marin). Marine data sheets are used to summarize the marine environment characteristics of the various sites considered, and to identify vulnerable areas requiring implementation of population protection measures, such as aquaculture areas, beaches or industrial water intakes, as well as areas of major ecological interest. Local climatological data (dominant sea currents as a function of meteorological or tidal conditions) serving as the basis for an initial environmental sampling strategy is provided whenever possible, along with a list of possible local contacts for operational management purposes. The STERNE simulation tool is designed to predict radionuclide dispersion and contamination in seawater and marine species by incorporating spatio-temporal data. 3D hydrodynamic forecasts are used as input data. Direct discharge points or

Trends in radionuclide concentrations for wildlife and food products near Hanford for the period 1971 through 1988

International Nuclear Information System (INIS)

Eberhardt, L.E.; Cadwell, L.L.; Price, K.R.; Carlile, D.W.

1989-10-01

The objective of this summary investigation was to identify trends in radionuclide concentrations for wildlife and food products sampled from 1971 through 1988 as part of the Hanford Site Environmental Monitoring Program. No upward trends in radionuclide concentrations were detected for any wildlife or food products. Several sample types demonstrated significantly declining radionuclide concentrations. Three factors appeared to be responsible for the trends. First, the cessation of atmospheric testing by the United States and Soviet Union in 1971 contributed to the decline of radionuclides in some samples. Second, contaminants discharged to the Columbia River were reduced subsequent to the 1971 shutdown of the last Hanford nuclear reactor that used a once-through cooling water design. The reactor closing resulted in declines in activation products in oysters from Willapa Bay and in whitefish from the Hanford Reach of the Columbia River. Third, reductions in radionuclide concentrations in Hanford wildlife suggested a decreasing availability of environmental contaminants to wildlife. Remediation of areas having environmental surface contaminants on the Hanford Site was identified as a probable cause. 5 refs., 4 figs., 2 tabs

Characterization of residual radionuclide contamination within and around commercial nuclear power plants

International Nuclear Information System (INIS)

Robertson, D.E.; Abel, K.H.; Thomas, C.W.; Lepel, E.A.; Evans, J.C.; Thomas, W.V.; Carrick, L.C.; Leale, M.W.

1985-07-01

To provide a statistically valid data base for the residual radionuclide inventories in nuclear power stations, Pacific Northwest Laboratory (PNL) was contracted to conduct an extensive sampling and measurements program at a number of nuclear power plants. This paper summarizes the results of the radionuclide characterization studies conducted at seven nuclear power stations from a decommissioning assessment viewpoint

Ecological risk assessment for radiological and chemical contaminants at a site with historical contamination

International Nuclear Information System (INIS)

Garisto, N.C.; Janes, A.; Peters, R.

2010-01-01

An Ecological Risk Assessment was carried out for a uranium conversion facility in Ontario, located on a site with a history of contamination. The ERA assessed risk to aquatic and terrestrial biota from exposure to radionuclides and non-radionuclides in soil and groundwater associated with the site. The results indicated no undue risk to aquatic biota from radionuclides. Small potential risks were identified for terrestrial biota at limited locations associated with this industrial site. Recommendations are provided for follow-up risk-informed activities. (author)

Study on the immunological and genetic effects induced by internal exposure to radionuclides

International Nuclear Information System (INIS)

Zhu Shoupeng; Wang Liuyi; Luan Meiling

1995-02-01

The immune system is the important part of defense mechanism in organism. Studies have demonstrated the high radiosensitivity of the immunocytes to internal radionuclide exposure. It is evident that serious functional disturbances and morphological changes of immune organs are induced by internal contamination of radionuclides, including suppression of division and proliferation of immunocytes, induction of irreversible sequelae, leading to injurious effects on both central and peripheral immune organs. In order to study the consequences of the injuries of genetic material caused by internal contamination of radionuclides, researches have developed from the harmful effects on parental generation to those on the offspring. The present paper reports the study on the genetic injuries of somatic and germ cells induced by internal radionuclide exposure. Emphasis is placed on the molecular basis of radio-genetic effect and the relations of the molecular basis of DNA injury to gene mutation and chromosome aberration

Radionuclide migration in the unsaturated zone with a variable hydrology

International Nuclear Information System (INIS)

Elert, M.; Collin, M.; Andersson, Birgitta; Lindgren, M.

1990-01-01

Radionuclide transport from contaminated ground water to the root zone of a soil has been modelled considering a variable hydrology. Hydrological calculations have been coupled with radionuclide transport calculations in order to study the influence of variations in flow rate and saturation, dispersion, and sorption. For non-sorbing radionuclides important seasonal variations in the root zone concentration were found. The dispersivity parameter proved to be very important for both sorbing and non-sorbing nuclides. In addition, some comparison calculations were made with a simple steady-state compartment model. (au)

Radionuclides in an arctic terrestrial ecosystem affected by atmospheric release from the Kraton-3 accidental underground nuclear explosion. 2001-2002

International Nuclear Information System (INIS)

Ramzaev, V.; Golikov, V.; Mishine, A.; Kaduka, M.; Burtcev, I.; Gedeonov, A.; Bulatenkov, Y.U.; Strand, P.; Brown, J.

2004-01-01

Current distributions of artificial radionuclides (ARN) were studied in the main compartments of a larch-tree forest lethally affected by a radioactive release from the Kraton-3 peaceful underground nuclear explosion (65.9 deg N, 112.3 deg E; Yakutia, Russia; 1978). Samples of soil, fungi, lichens, mosses, grasses, shrubs and trees were obtained at points belonging to four zones categorised by the severity of the ecosystem damage. Sampling was supplemented by dose rate measurements in air and mapping. The area of forest characterised by 100% lethality to adult larches (Larix gmelinii) and with partial, visually-detectable damage of other more radio-resistance species (e.g. lichens, mosses) covers a territory of approximately 1.2 km 2 . Elevated levels of long-lived ARN were found at all sampling sites. Maximum registered levels of the ground contamination with radionuclides of Cs, Sr and Pu were three orders of magnitude higher than those expected from global fallout. The ratios of 137 Cs to some other significant radionuclides in the ground contamination were as follows [mean (range)]: 90 Sr - 0.57(0.02-0.93); 239,240 Pu 44(25-72); 60 Co 470(220-760). Twenty-three years after a discrete contamination event, 90-95% of the total deposited radiocesium and plutonium has still remained in the lichen-moss on-ground cover and in the top 5 cm organic soil layer. At the same time, vertical and horizontal migrations of 90 Sr in soil were more pronounced. Strong surface contamination with 137 Cs, 90 Sr and plutonium was detected at the twigs and bark of the dead larches. The young larches that grew at the contaminated area following the initial destruction of the forest demonstrated a substantial ability to accumulate 137 Cs, 90 Sr and plutonium via roots, while the bushes selectively accumulated mainly radiostrontium. In contrast, some fungi concentrated mostly radiocesium. The levels of gamma dose rate in air and the environmental contamination with 137 Cs were found to

Decontamination of radionuclides in food

Energy Technology Data Exchange (ETDEWEB)

Ohmomo, Yoichiro [Institute for Environmental Sciences, Aomori (Japan)

1994-03-01

The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author).

Decontamination of radionuclides in food

International Nuclear Information System (INIS)

Ohmomo, Yoichiro

1994-01-01

The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author)

[Decorporation agents for internal radioactive contamination].

Science.gov (United States)

Ohmachi, Yasushi

2015-01-01

When radionuclides are accidentally ingested or inhaled, blood circulation or tissue/organ deposition of the radionuclides causes systemic or local radiation effects. In such cases, decorporation therapy is used to reduce the health risks due to their intake. Decorporation therapy includes reduction and/or inhibition of absorption from the gastrointestinal tract, isotopic dilution, and the use of diuretics, adsorbents, and chelating agents. For example, penicillamine is recommended as a chelating agent for copper contamination, and diethylene triamine pentaacetic acid is approved for the treatment of internal contamination with plutonium. During chelation therapy, the removal effect of the drugs should be monitored using a whole-body counter and/or bioassay. Some authorities, such as the National Council on Radiation Protection and Measurements and International Atomic Energy Agency, have reported recommended decorporation agents for each radionuclide. However, few drugs are approved by the US Food and Drug Administration, and many are off-label-use agents. Because many decontamination agents are drugs that have been available for a long time and have limited efficacy, the development of new, higher-efficacy drugs has been carried out mainly in the USA and France. In this article, in addition to an outline of decorporation agents for internal radioactive contamination, an outline of our research on decorporation agents for actinide (uranium and plutonium) contamination and for radio-cesium contamination is also presented.

The behaviour of long-lived redox sensitive radionuclides in soil-plant system during the process of climate change

Energy Technology Data Exchange (ETDEWEB)

Semioshkina, N.; Staudt, C.; Kaiser, C. [Helmhotz Zetrum Muenchen (Germany); Proehl, G. [International Atomic Energy Agency - IAEA (International Atomic Energy Agency (IAEA)); Noseck, U.; Fahrenholz, C. [Gesellschaft fuer Anlagen- und Reaktorsicherheit - GRS (Germany)

2014-07-01

One important aspect of climate changes for the long-term safety assessment of radioactive waste repositories is its impact on exposure pathways for humans in the future, which are dependent on the environmental characteristics mentioned. It is conceivable that effects or processes occurring during climate changes lead to an increased accumulation and/or release of radionuclides in the biosphere resulting in higher doses compared to that calculated for discrete climate states. In order to shed light on this question key processes are identified which might lead to such an increased accumulation and/or release of radionuclides. The transition from one climate to another can cause changes in the physicochemical composition of radionuclides: some of them may become more available for plant uptake and due to this, their activity concentration in the plants increases. Other radionuclides maybe stronger bound to soil and their activity concentration in plants decreases. Such changes might also cause remobilization of radionuclides from localised areas with contaminated sediments, their re-suspension and transfer to the surrounding areas. A suitable illustration of the processes related to the changes of the redox potential is the examination of a dry lake or fen bed for agricultural purposes as pasture or ameliorated pasture. In these cases the accumulation of radionuclides in the lake or fen sediment is followed by their release and increasing mobility after agricultural processing of the dry bed of lake or fen. Ploughing of the soil leads to increased supply of oxygen to previous anoxic soil layers causing an increase in redox potential. The presented model describes a scenario, where the land is initially very humid and very low Eh-values cause high sorption and accumulation of radionuclides in soil particles. Then this land is dried out, the redox potential increases and redox sensitive radionuclides change their speciation and their behaviour. Such processes might

Sources of anthropogenic radionuclides in the environment: a review

International Nuclear Information System (INIS)

Hu Qinhong; Weng Jianqing; Wang Jinsheng

2010-01-01

Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview on sources of anthropogenic radionuclides in the environment, as well as a brief discussion of salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current developments that have lead, or could potentially contribute, to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) uranium mining and milling; (5) commercial fuel reprocessing; (6) geological repository of high-level nuclear wastes that include radionuclides might be released in the future, and (7) nuclear accidents. Then, we briefly summarize the inventory of radionuclides 99 Tc and 129 I, as well as geochemical behavior for radionuclides 99 Tc, 129 I, and 237 Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment; biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

{sup 137}Cs, {sup 90}Sr, {sup 241}Am and {sup 239+240}Pu radionuclides speciation in soils of the former Semipalatinsk test site

Energy Technology Data Exchange (ETDEWEB)

Kabdyrakova, A.M.; Kunduzbaeva, A.Y.; Lukashenko, S.N.; Magasheva, R.Y. [Institute of radiation safety and ecology (Kazakhstan)

2014-07-01

The paper presents results of studies into {sup 137}Cs and {sup 90}Sr, {sup 241}Am and {sup 239+240}Pu techno-genic radionuclides speciation in soils of ecosystems at different topography of the Semipalatinsk Test Site (STS), exposed to different nuclear testing. The data were obtained for radionuclides speciation in soils of the following STS ecosystems: - grassland ecosystems within near-portal areas of tunnels - horizontal adits constructed for nuclear testing, affected by radioactive-contaminated water flows from the tunnels of Degelen Site; - steppe ecosystems, exposed to ground radioactive contamination resulted from above-ground and aerial nuclear testing of different yield, as well as simulation (hydrodynamic and hydro-nuclear) experiments at 'Experimental Field' testing site. - steppe ecosystems, exposed to ground radioactive contamination caused by testing of liquid and powdery radiological warfare weapon (RWW) at Site '4 a'; - 'Northern' and 'Western' areas of STS, where concentration level of artificial radionuclides in soil is comparable with the level of global fall-outs ('background' areas). To study the radionuclides speciation, method of sequential extraction was applied, and water-soluble, exchange, organic mobile and tightly bound forms were separated. Feature of the studied grassland ecosystems is that they are developed solely along the bed of water streams flowing from tunnels and are located at small area of 1-2 m{sup 2}. Radioactive contamination of soil is caused by radioactive contaminant sorption by sediments. Despite the significant space limitation of the ecosystems content of radionuclides speciation in soil greatly varies, particularly readily-soluble and mobile forms. The variation may be explained by high humidity which makes possible both sorption and desorption processes. If basic radionuclides contributing to radioactive contamination of grassland soils at Degelen Site are {sup

The biological transport of radionuclides in grassland and freshwater ecosystems

International Nuclear Information System (INIS)

Rudge, S.A.

1989-12-01

This thesis examines the biological transport of radionuclides through terrestrial and aquatic ecosystems, with particular reference to radiocaesium. The semi-natural grassland habitat was located at Drigg, W. Cumbria, contaminated primarily by radioactive fallout, from several sources over the past decade. Advantage was made of the deposition of radionuclides from the Chernobyl reactor incident, which occurred during the early stages of the investigation. The study examined the distribution of radiocaesium for the major components of the grassland ecosystem, within the soil-plant-invertebrate-small mammal food chain. Data concerning temporal fluctuation of radionuclide transfer factors between food chain components are presented. The final section examines the spatial distribution of radiocaesium in sediment and the freshwater eel (Anguilla anguilla) in a small stream contaminated by radioactive effluent. The relationship between activity levels in eels and the sediments in which they rest and forage was investigated. Factors influencing uptake of radiocaesium in freshwater fish were also examined. (author)

Radioactive contamination of the Shagan river ecosystem components with artificial radionuclides

International Nuclear Information System (INIS)

Subbotin, S.B.; Lukashenko, S.N.; Larionova, N.V.; Yakovenko, Yu.Yu.

2008-01-01

90 Sr distribution in water, it was established that the radionuclides have absolutely different sources. Whereas the nature of tritium presence in the water is quite understandable, the source of 90 Sr has not been studied yet. To determine the reasons for noticeable increase of the 90 Sr concentration in water and the ways of its proliferation into the river, additional investigations are necessary. Possible mechanisms for 90 Sr proliferation into the river may be its inflow with ground waters, plane washing off, washing out of 90 Sr from contaminated man-made soils of Atomic Lake by atmospheric precipitations. The present-day situation is complicated by active development of pasture cattle breeding and stocking of fodder crops within the bank zone of the shagan river. High tritium concentration, up to 24000 Bq/l, was also registered in the vegetation of the river-bank zone. The presence of tritium was detected in animal products produced by farms situated on the banks of the Shagan river. Tritium concentration in milk samples reaches 5.0*10 3 Bq/l, which does not exceed maximal permissible values but requires thorough investigation of the problem as tritium concentration in the Shagan waters may vary in a wide range

Design and manufacturing of nuclear non destructive measurement systems and coupled metrology in order to quantify the radionuclides contaminating the wastes and the processes of the nuclear industry

International Nuclear Information System (INIS)

Saurel, N.

2013-01-01

The non-destructive nuclear measurement has to provide responses for the main challenges of the nuclear industry such as nuclear facility safety, health, environmental impact, performance, reliability and cost control. The goal of the non-destructive nuclear measurement is to characterize, without any deterioration, an object contaminated by one or more radionuclides. The passive or active nuclear measurement are utilized for quantifying the radionuclides in the effluents, the liquid and solid wastes and the nuclear material hold-up. It is also deployed for the process control. In this case, it is a standard production control but, the most of the time, it controls the validity of the safety domain of the production unit. The results of these measurements are used to establish the radiological inventory or the nuclear material balance. The radiological inventory is needed for the nuclear wastes outlets while the nuclear material balance is needed to follow through with the criticality units. The most important objective is to give the quantitative and/or qualitative value and its uncertainty are confident of the radionuclides contaminating the object. This contaminated object might be of different geometrical shapes, sizes or physico-chemical compositions. In order to be efficient, the non-destructive nuclear measurement has to include the apparatus, the measurement actions, the settings and the use of the coupled methodologies. I relate, in this memoir, my main research and development works that I drove or in which I took part for achieving these goals. These works are about the metrology of nuclear radiations and are used in three main types of measurement which are the gamma spectrometry, the alpha spectrometry and the passive or active neutron counting. (author) [fr

Understanding transfer modes of radionuclides to plants

International Nuclear Information System (INIS)

Hurtevent, P.

2010-01-01

This article briefly comments recent works performed by the IRSN in order to better quantify the transfer of radionuclides from the environment to plants. Three major processes have been studied: root transfer or uptake, translocation, and organic matter recycling (or contamination recycling). The first one depends on the plant and on the soil where it grows. As far as translocation is concerned, the aerial contamination penetrates the plant through the leaves. The third one occurs when broken branches and leaves which have been contaminated, fall on the ground. Some measurements performed in forests near Chernobyl are evoked

Nuclear contamination of water resources

International Nuclear Information System (INIS)

1990-01-01

In the wake of the Chernobyl accident, the vulnerability of the water cycle to radionuclide contamination has been an issue of great concern. The impact of the event throughout Europe has been highly variable and wide-ranging, and has demonstrated the need to evaluate the potential risk to drinking water supplies, soilwater and the food chain. This book provides information on radiological standards as they exist at present, on the methods of monitoring, and on concepts in design to minimize risk and to highlight the possible consequences of a nuclear event. With contributions from engineers and scientists from eight countries, this book is a unique source of information about present radiological standards and monitoring requirements. It also includes comprehensive coverage of the effects on water resources of, and deals with the development of management strategies designed to cope with, a nuclear event. There are 19 papers all indexed separately. These are divided into sections -introduction, present radiological standards relating to drinking water, radiological monitoring requirements, the consequences of a nuclear event on water resources and water resource management strategy. The discussion at the end of each section is recorded. (author)

A basis for the forest economy conception in the condition of the radioactive contamination

International Nuclear Information System (INIS)

Sidorov, V.I.; Chilimov, A.I.; Tikhomirov, F.A.; Shcheglov, A.I.; Panfilov, A.V.

1992-01-01

On the basis of data on radiation conditions in fores biogeocenoses, the radionuclide migration and the radionuclide content in forest economy products and the dose commitments to various catego rives the forest economy workers, the main theses are presented to keep it in conditions of the radioactive contamination. The base for the theses are done: about radionuclide migration (Cs-137, Ru-106, Cr-144) through the main components of the forest biogeocinoses; about the Cs-137 distribution of the zoofund lands; about the zone radionuclide contamination; about radionuclide content in the forest economy production about a wood plant radiosensitivity. 8 refs.; 6 tabs

The problem of radioactive contamination inhomogeneity and simulation of the transport of radionuclides through agroecosystems

International Nuclear Information System (INIS)

Girij, V.A.; Shpinar, L.I.; Yaskovets, I.I.; Zaitov, V.R.; Hille, R.

1997-01-01

The analyses of the measurement data on the territory of the Ukrainian Polesie region carried out by the Research Centre Juelich and the Ukrainian Institute of Radioecology shows that there is a high degree of inhomogeneity for the contamination pattern, they transfer from soil to the biosphere and for the food consumption. Therefore, a deterministic environmental assessment model may not be convenient because most processes are not known in detailed. In this situation a probabilistic approach seems to be more promising. In this report presented a dynamic model for the transfer of radioactivity in terrestrial food chains that fit to the regionally conditions and agricultural practice. The living organism will be treated as dynamic system subject to random action of radioactivity. This system is described by stochastic differential equations of Langevene's type. Starting from this base we calculated a distribution function of radionuclide body burdens for inhabitant ensembles under the assumptions that entering of activity into organisms is a random temporary function that can be approximated by certain impulse Poison processes. A comparison of calculated distribution function is carried out with measurement results of internal body burden. It shown a satisfactory description of the real situation found for four investigated villages of Ukrainian Polesie region (Olevsk, Narodichi, Vezhitsa and Stare Selo) that were characterized by different degree of contamination and different degree of inhomogeneity

Aspects of radiation exposure amongst the population after release of radionuclides from terminal stores

International Nuclear Information System (INIS)

Proehl, G.; Mueller, H.; Paretzke, H.G.

1989-08-01

The release of radionuclides from terminal stores may lead to the contamination of ground water lying close to the surface, after the radionuclides have migrated within the covering rock. Use of this water can result in radiation exposure for human beings along many exposure pathways. In order to assess the radiation exposure from these exposure pathways the model ECOSYS-87-B was developed, as an extension of ECOSYS (Jacobi et al. 1985). On the basis of a standardized contamination of the ground water, the potential radiation exposure of a one-year-old and an adult are calculated, under the assumption that the entire food supply of these persons was produced using radioactively contaminated water. Special questions on the transfer of radionuclides in food chains are discussed, and, in particular, the mineral content of the water and the influence of the chemical form of the radionuclides dissolved in the ground water on their transfer within the food chain are explained. There is also a study of the extent to which various physiologically-based nutritional habits influence the radiation exposure of a human being. Various criteria for the evaluation of radiation exposure are discussed. (orig./HP) [de

PATHWAY: a simulation model of radionuclide-transport through agricultural food chains

International Nuclear Information System (INIS)

Kirchner, T.B.; Whicker, F.W.; Otis, M.D.

1982-01-01

PATHWAY simulates the transport of radionuclides from fallout through an agricultural ecosystem. The agro-ecosystem is subdivided into several land management units, each of which is used either for grazing animals, for growing hay, or for growing food crops. The model simulates the transport of radionuclides by both discrete events and continuous, time-dependent processes. The discrete events include tillage of soil, harvest and storage of crops,and deposition of fallout. The continuous processes include the transport of radionuclides due to resuspension, weathering, rain splash, percolation, leaching, adsorption and desorption of radionuclides in the soil, root uptake, foliar absorption, growth and senescence of vegetation, and the ingestion assimilation, and excretion of radionuclides by animals. Preliminary validation studies indicate that the model dynamics and simulated values of radionuclide concentrations in several agricultural products agree well with measured values when the model is driven with site specific data on deposition from world-wide fallout

Technical note: Efficient online source identification algorithm for integration within a contamination event management system

Science.gov (United States)

Deuerlein, Jochen; Meyer-Harries, Lea; Guth, Nicolai

2017-07-01

Drinking water distribution networks are part of critical infrastructures and are exposed to a number of different risks. One of them is the risk of unintended or deliberate contamination of the drinking water within the pipe network. Over the past decade research has focused on the development of new sensors that are able to detect malicious substances in the network and early warning systems for contamination. In addition to the optimal placement of sensors, the automatic identification of the source of a contamination is an important component of an early warning and event management system for security enhancement of water supply networks. Many publications deal with the algorithmic development; however, only little information exists about the integration within a comprehensive real-time event detection and management system. In the following the analytical solution and the software implementation of a real-time source identification module and its integration within a web-based event management system are described. The development was part of the SAFEWATER project, which was funded under FP 7 of the European Commission.

Radionuclides in food

International Nuclear Information System (INIS)

Fernandez Gomez, Isis Maria

2008-01-01

The sources of the presence of radionuclides in food are presented: natural radiation and artificial radiation. The transfer of radionuclides through food chains, intakes of radionuclides to the body with its partners effective doses and typical consumption of basic foods of a rural adult population are exposed as main topics. Also the radiation doses from natural sources and exposure to man by ingestion of contaminated food with radionuclides of artificial origin are shown. The contribution of the food ingestion to the man exposure depends on: characteristics of radionuclide, natural conditions, farming practices and eating habits of the population. The principal international organizations in charge of setting guide levels for radionuclides in food are mentioned: standards, rules and the monitoring. It establishes that a guide is necessary for the food monitoring; the alone CODEX ALIMENTARIUS is applicable to emergency situations and the generic action levels proposed by the CODEX not satisfy all needs (no guiding international levels for planned or existing situations such as NORM). There are handled mainly socio-economic and political aspects. Among the actions to be taken are: to assure a public comprehensive information over the risk evaluation in food; to reinforce the collaboration among the different international organizations (WHO, IAEA, ICRP, EC) in relation with the food of set; to give follow-up to the control of the drinkable water and NORM's presence in the food. In addition, it is possible to create the necessary mechanisms to reduce the number of irrelevant measures and bureaucratic useless steps (certificates); to promote the exchange between the different institutions involved in the topic of the food, with relation to the acquired experiences and learned lessons. Likewise, it might examine the possibility of a multidisciplinary approximation (radioactive and not radioactive pollutants); to elaborate a technical guide to assure the

Radionuclide characterization of environmental air around nuclear facilities

International Nuclear Information System (INIS)

Gede Sutresna Wijaya; Anung Muharini

2015-01-01

Air is an important environmental component in human life. Presence of air pollutants or contaminants will have a negative impact on human health. According to the existence of a nuclear facility in Yogyakarta, the characterization of radionuclides in the air is absolutely necessary to ensure the safety of people and the environment and also to supervise the safe operation of the facility. In this research the characterization of radionuclides in the air was carried through the air sampling by using High Volume Air Sampler equipped with filter TFA 2133, followed by analysis using combination of a gamma and alpha spectrometers. The concentration of radioactivity in the air fluctuates depending on the time and duration of sampling. Characterization of gamma emitting radionuclides in the air is dominated by radon progeny radionuclides such as 214 Pb, 214 Bi with activity 20.09 ± 1.23 until 32.91 ± 4.87 Bq/m 3 and 31.22 ± 1.76 until 44.25 ± 4.91 Bq/m 3 . Alpha emitter radionuclide was dominated by 214 Po (7.69 MeV) which is also radon progeny and a primordial radionuclides. It can be concluded that the presence of radionuclides in the environmental air not as a product resulting from the operation of nuclear facilities in Yogyakarta. (author)

The results of artificial radionuclides monitoring in the Baltic sea

International Nuclear Information System (INIS)

Astrauskiene, N.; Lukinskiene, M; Zemaitiene, G.

1994-01-01

Long-term radionuclides volume activity (v.a.) monitoring (1976-1990) data showed that measurement results obtained in steady observation station give reliable information of the coastal area of the Baltic sea radioactive equilibrium between atmosphere and surface water was observed in the coastal zone. Chernobyl Power Plant accident influenced upon the Baltic sea coastal water by radionuclides 137 Cs and 144 Ce. Radionuclide 90 Sr volume activity was practically unchangerable. The mechanism of radionuclides fallout from atmosphere are various. lt can be illustrated by 137 Cs and 144 Ce a.v. structure field variations in open sea and coastal zone near Juodkrante. The Baltic sea inhomogeneous contamination by radionuclide 137 Cs in 1988-1990 leads to equalization of 137 Cs v.a. in the surface waters and it causes v.a. increase in coastal waters. (author)

Implementation guide of internal contamination control

International Nuclear Information System (INIS)

Balter, Henia; Savio, Eduardo; Souto, Beatriz

1994-01-01

A review of current methods of contamination control for radioisotopes 131I, 125I and 99mTc, periodic control of personnel exposed to radiation.Maximum permissible body burden (Mpbb) for each radionuclide,radiotoxicity as danger of internal contamination directly related with Let, type of radiation,Ali values for various radionuclides and external irradiation as an opposed factor.Effective half life,examples, 99mTc in urine,iodine in thyroid caption, 99m Tc absorption by skin and mouth. Procedure of control and calculation by measurement of urine samples in a gamma spectrometer. Iodine thyroid caption by monitoring of thyroid with a solid NaI(TI)scintillator taking as background radiation the activity of upper leg muscle. Standard solutions are prepared to fill a thyroid phantoms.Results must not be higher than Mpbb of corresponding radionuclide.Bibliography

PABLM: a computer program to calculate accumulated radiation doses from radionuclides in the environment

Energy Technology Data Exchange (ETDEWEB)

Napier, B.A.; Kennedy, W.E. Jr.; Soldat, J.K.

1980-03-01

A computer program, PABLM, was written to facilitate the calculation of internal radiation doses to man from radionuclides in food products and external radiation doses from radionuclides in the environment. This report contains details of mathematical models used and calculational procedures required to run the computer program. Radiation doses from radionuclides in the environment may be calculated from deposition on the soil or plants during an atmospheric or liquid release, or from exposure to residual radionuclides in the environment after the releases have ended. Radioactive decay is considered during the release of radionuclides, after they are deposited on the plants or ground, and during holdup of food after harvest. The radiation dose models consider several exposure pathways. Doses may be calculated for either a maximum-exposed individual or for a population group. The doses calculated are accumulated doses from continuous chronic exposure. A first-year committed dose is calculated as well as an integrated dose for a selected number of years. The equations for calculating internal radiation doses are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and MPC's of each radionuclide. The radiation doses from external exposure to contaminated water and soil are calculated using the basic assumption that the contaminated medium is large enough to be considered an infinite volume or plane relative to the range of the emitted radiations. The equations for calculations of the radiation dose from external exposure to shoreline sediments include a correction for the finite width of the contaminated beach.

PABLM: a computer program to calculate accumulated radiation doses from radionuclides in the environment

International Nuclear Information System (INIS)

Napier, B.A.; Kennedy, W.E. Jr.; Soldat, J.K.

1980-03-01

A computer program, PABLM, was written to facilitate the calculation of internal radiation doses to man from radionuclides in food products and external radiation doses from radionuclides in the environment. This report contains details of mathematical models used and calculational procedures required to run the computer program. Radiation doses from radionuclides in the environment may be calculated from deposition on the soil or plants during an atmospheric or liquid release, or from exposure to residual radionuclides in the environment after the releases have ended. Radioactive decay is considered during the release of radionuclides, after they are deposited on the plants or ground, and during holdup of food after harvest. The radiation dose models consider several exposure pathways. Doses may be calculated for either a maximum-exposed individual or for a population group. The doses calculated are accumulated doses from continuous chronic exposure. A first-year committed dose is calculated as well as an integrated dose for a selected number of years. The equations for calculating internal radiation doses are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and MPC's of each radionuclide. The radiation doses from external exposure to contaminated water and soil are calculated using the basic assumption that the contaminated medium is large enough to be considered an infinite volume or plane relative to the range of the emitted radiations. The equations for calculations of the radiation dose from external exposure to shoreline sediments include a correction for the finite width of the contaminated beach

Trends in radionuclide concentrations for wildlife and food products near Hanford for the period 1971-1988

International Nuclear Information System (INIS)

Cadwell, L.L.; Eberhardt, L.E.; Price, K.R.; Carlile, D.W.

1990-01-01

We evaluated the Hanford environmental data base for trends in radionuclide concentrations in wildlife and food products sampled from 1971 through 1988 on or near the U.S. Department of Energy's Hanford Site in southeastern Washington. Although statistical analyses showed short-term changes, no upward trends in radionuclide concentrations were detected. Many samples showed a significant decline in some radionuclides, particularly for 137 Cs. Concentrations of 65 Zn also showed a downward trend in many samples. Cessation of atmospheric testing by the United States and the USSR in 1971 contributed to the decline in radionuclide levels in some samples. Contaminants discharged to the Columbia River at Hanford were reduced after shutdown of the last once-through cooling-water reactor in 1971. A decline in concentrations of 65 Zn in oysters from Willapa Bay and 60 Co and 65 Zn in mountain whitefish from the Hanford Reach of the Columbia River are attributable to reactor closure. There was also an apparent reduction in availability of radiological contamination to Hanford wildlife after decommissioning of waste-water disposal ponds and remediation of contaminated terrestrial sites

Contaminant Boundary at the Faultless Underground Nuclear Test

International Nuclear Information System (INIS)

Greg Pohll; Karl Pohlmann; Jeff Daniels; Ahmed Hassan; Jenny Chapman

2003-01-01

The U.S. Department of Energy (DOE) and the Nevada Division of Environmental Protection (NDEP) have reached agreement on a corrective action strategy applicable to address the extent and potential impact of radionuclide contamination of groundwater at underground nuclear test locations. This strategy is described in detail in the Federal Facility Agreement and Consent Order (FFACO, 2000). As part of the corrective action strategy, the nuclear detonations that occurred underground were identified as geographically distinct corrective action units (CAUs). The strategic objective for each CAU is to estimate over a 1,000-yr time period, with uncertainty quantified, the three-dimensional extent of groundwater contamination that would be considered unsafe for domestic and municipal use. Two types of boundaries (contaminant and compliance) are discussed in the FFACO that will map the three-dimensional extent of radionuclide contamination. The contaminant boundary will identify the region wi th 95 percent certainty that contaminants do not exist above a threshold value. It will be prepared by the DOE and presented to NDEP. The compliance boundary will be produced as a result of negotiation between the DOE and NDEP, and can be coincident with, or differ from, the contaminant boundary. Two different thresholds are considered for the contaminant boundary. One is based on the enforceable National Primary Drinking Water Regulations for radionuclides, which were developed as a requirement of the Safe Drinking Water Act. The other is a risk-based threshold considering applicable lifetime excess cancer-risk-based criteria The contaminant boundary for the Faultless underground nuclear test at the Central Nevada Test Area (CNTA) is calculated using a newly developed groundwater flow and radionuclide transport model that incorporates aspects of both the original three-dimensional model (Pohlmann et al., 1999) and the two-dimensional model developed for the Faultless data decision

Doses in various parts of the biosphere due to long-lived radionuclides originating from deep geological repositories

International Nuclear Information System (INIS)

Bergstroem, U.; Karlsson, Sara; Nordlinder, S.

1999-01-01

Turnover of radionuclides and resulting doses to man were modelled for various parts of the biosphere. This was made for different scenarios of leakage of radionuclides from a deep geological repository for spent nuclear fuel and other waste. In previous studies, the emphasis was on doses from contaminated ground water represented by a well or various surface waters. This was because radionuclides were assumed to be released directly to surface water, the use of which subsequently formed the major pathway for radionuclides to agricultural areas. In the present study, radionuclides were considered to reach lakes, running waters, coastal areas, agricultural areas and peat areas. The inflow of radionuclides to agricultural areas was supposed to be from below. Doses due to direct use of contaminated ground water from a well were also considered. Altogether 44 radionuclides contained in the waste were assumed to be released during 10,000 years, with a rate of 1 Bq/year of each radionuclide, to each of the above mentioned biospheric parts. During that time, the biospheric conditions were assumed to be the same as they are today. Doses to the critical group were calculated by exposure pathways specific for each entry-point All calculations were performed with estimation of confidence due to time-dependent parameter variation and uncertainty in input values. The results indicate that drinking water from wells is not a critical exposure pathway for all studied radionuclides. Instead, inflow of contaminated water to soil and peat bogs may be crucial for illustration of doses for geological high-level waste disposal. Improved knowledge of processes at the geosphere-biosphere interface is therefore important

Bioremediation of Metals and Radionuclides: What It Is and How It Works (2nd Edition)

Energy Technology Data Exchange (ETDEWEB)

Palmisano, Anna; Hazen, Terry

2003-09-30

This primer is intended for people interested in environmental problems of the U.S. Department of Energy (DOE) and in their potential solutions. It will specifically look at some of the more hazardous metal and radionuclide contaminants found on DOE lands and at the possibilities for using bioremediation technology to clean up these contaminants. The second edition of the primer incorporates recent findings by researchers in DOE's Natural and Accelerated Bioremediation Research (NABIR) Program. Bioremediation is a technology that can be used to reduce, eliminate, or contain hazardous waste. Over the past two decades, it has become widely accepted that microorganisms, and to a lesser extent plants, can transform and degrade many types of contaminants. These transformation and degradation processes vary, depending on the physical-chemical environment, microbial communities, and nature of the contaminant. This technology includes intrinsic bioremediation, which relies on naturally occurring processes, and accelerated bioremediation, which enhances microbial degradation or transformation through the addition of nutrients (biostimulation) or inoculation with microorganisms (bioaugmentation). Over the past few years, interest in bioremediation has increased. It has become clear that many organic contaminants such as hydrocarbon fuels can be degraded to relatively harmless products such as CO{sub 2} (the end result of the degradation process). Waste water managers and scientists have also found that microorganisms can interact with metals and convert them from one chemical form to another. Laboratory tests and ex situ bioremediation applications have shown that microorganisms can change the valence, or oxidation state, of some heavy metals (e.g., chromium and mercury) and radionuclides (e.g., uranium) by using them as electron acceptors. In some cases, the solubility of the altered species decreases and the contaminant is immobilized in situ, i.e., precipitated into

Radionuclides and the birds at Ravenglass

International Nuclear Information System (INIS)

Lowe, V.P.W.

1991-01-01

Since 1983 concern has been expressed about the apparent decline in numbers of birds in the Ravenglass estuary in west Cumbria, particularly of the black-headed gull colony on the Drigg dunes, and suggestions have been made that this decline might be due to excessive radiation in the birds' food and their general environment. Twelve species of marine invertebrates from Ravenglass, known to be important foods for birds, were analysed, and further samples were taken from sites along the west Cumbrian coast. None of these samples showed excessive contamination with any of the radionuclides analysed. Analysis of a sample of bird carcasses from the area showed oystercatchers (Haematopus ostralegus) and shelduck (Tadorna tadorna) to have some of the highest concentrations of 137 Cs in their tissues; yet their breeding success and populations were not affected. Black-headed gulls were found to be feeding mainly inland, and were the least contaminated with radionuclides of all the birds at Ravenglass, yet this species and its breeding success were in decline. Calculations of the total dose equivalent rate to the whole body of the most contaminated black-headed gull amounted to 9.8 x 10 -4 mSv h -1 (∼ 8.4 x 10 -4 mGy h -1 , whole-body absorbed dose rate), and the background exposure dose was of the order of 8.3 x 10 -4 mGy h -1 . As a minimum chronic dose of 1000 mGy day -1 has been found necessary to retard growth of nestling birds, and 9600 mGy over 20 days of incubation to cause the death of 50% of embryos in black-headed gulls' eggs, the concentrations of radionuclides in the foods, body tissues and general environment were at least three orders of magnitude too low to have had any effects. (author)

A numerical investigation of vapor intrusion--the dynamic response of contaminant vapors to rainfall events.

Science.gov (United States)

Shen, Rui; Pennell, Kelly G; Suuberg, Eric M

2012-10-15

The U.S. government and various agencies have published guidelines for field investigation of vapor intrusion, most of which suggest soil gas sampling as an integral part of the investigation. Contaminant soil gas data are often relatively more stable than indoor air vapor concentration measurements, but meteorological conditions might influence soil gas values. Although a few field and numerical studies have considered some temporal effects on soil gas vapor transport, a full explanation of the contaminant vapor concentration response to rainfall events is not available. This manuscript seeks to demonstrate the effects on soil vapor transport during and after different rainfall events, by applying a coupled numerical model of fluid flow and vapor transport. Both a single rainfall event and seasonal rainfall events were modeled. For the single rainfall event models, the vapor response process could be divided into three steps: namely, infiltration, water redistribution, and establishment of a water lens atop the groundwater source. In the infiltration step, rainfall intensity was found to determine the speed of the wetting front and wash-out effect on the vapor. The passage of the wetting front led to an increase of the vapor concentration in both the infiltration and water redistribution steps and this effect is noted at soil probes located 1m below the ground surface. When the mixing of groundwater with infiltrated water was not allowed, a clean water lens accumulated above the groundwater source and led to a capping effect which can reduce diffusion rates of contaminant from the source. Seasonal rainfall with short time intervals involved superposition of the individual rainfall events. This modeling results indicated that for relatively deeper soil that the infiltration wetting front could not flood, the effects were damped out in less than a month after rain; while in the long term (years), possible formation of a water lens played a larger role in determining

Proceedings from the Workshop on Phytoremediation of Inorganic Contaminants

International Nuclear Information System (INIS)

Brown, J.T.; Matthern, G.; Glenn, A.; Kauffman, J.; Rock, S.; Kuperberg, M.; Ainsworth, C.; Waugh, J.

2000-01-01

The Metals and Radionuclides Product Line of the US Department of Energy (DOE) Subsurface Contaminants Focus Area (SCFA) is responsible for the development of technologies and systems that reduce the risk and cost of remediation of radionuclide and hazardous metal contamination in soils and groundwater. The rapid and efficient remediation of these sites and the areas surrounding them represents a technological challenge. Phytoremediation, the use of living plants to cleanup contaminated soils, sediments, surface water and groundwater, is an emerging technology that may be applicable to the problem. The use of phytoremediation to cleanup organic contamination is widely accepted and is being implemented at numerous sites. This workshop was held to initiate a discussion in the scientific community about whether phytoremediation is applicable to inorganic contaminants, such as metals and radionuclides, across the DOE complex. The Workshop on Phytoremediation of Inorganic Contaminants was held at Argonne National Laboratory from November 30 through December 2, 1999. The purpose of the workshop was to provide SCFA and the DOE Environmental Restoration Program with an understanding of the status of phytoremediation as a potential remediation technology for DOE sites. The workshop was expected to identify data gaps, technologies ready for demonstration and deployment, and to provide a set of recommendations for the further development of these technologies

Proceedings from the Workshop on Phytoremediation of Inorganic Contaminants

Energy Technology Data Exchange (ETDEWEB)

J. T. Brown; G. Matthern; A. Glenn (INEEL); J. Kauffman (EnviroIssues); S. Rock (USEPA); M. Kuperberg (Florida State U); C. Ainsworth (PNNL); J. Waugh (Roy F. Weston Assoc.)

2000-02-01

The Metals and Radionuclides Product Line of the US Department of Energy (DOE) Subsurface Contaminants Focus Area (SCFA) is responsible for the development of technologies and systems that reduce the risk and cost of remediation of radionuclide and hazardous metal contamination in soils and groundwater. The rapid and efficient remediation of these sites and the areas surrounding them represents a technological challenge. Phytoremediation, the use of living plants to cleanup contaminated soils, sediments, surface water and groundwater, is an emerging technology that may be applicable to the problem. The use of phytoremediation to cleanup organic contamination is widely accepted and is being implemented at numerous sites. This workshop was held to initiate a discussion in the scientific community about whether phytoremediation is applicable to inorganic contaminants, such as metals and radionuclides, across the DOE complex. The Workshop on Phytoremediation of Inorganic Contaminants was held at Argonne National Laboratory from November 30 through December 2, 1999. The purpose of the workshop was to provide SCFA and the DOE Environmental Restoration Program with an understanding of the status of phytoremediation as a potential remediation technology for DOE sites. The workshop was expected to identify data gaps, technologies ready for demonstration and deployment, and to provide a set of recommendations for the further development of these technologies.

Effect of industrial pollution on behaviour of radionuclides in forest ecosystems

International Nuclear Information System (INIS)

Outola, I.

2009-01-01

To investigate how and to what extent industrial pollution affects the behaviour of radionuclides in forest ecosystems, studies were conducted in the vicinity of two Cu-Ni smelters: one in a pine forest at Harjavalta, Finland, and the other in a spruce forest at Monchegorsk, Russia. Industrial pollution had significant effects on the distribution of radionuclides in soil horizons. With the increase in pollution towards the smelter, radionuclides were accumulated more in the litter layer because the conversion of litter into organic material was diminished due to inhibited microbial activity. As a result, the organic layer contained less radionuclides towards the smelter. The effect of industrial pollution on soil-to-plant transfer was complex. The effect varied with radionuclide, plant species and also on forest type. For 137 Cs, soil-to-plant transfer decreased significantly as industrial pollution increased in pine forest, whereas the decrease was less pronounced in spruce forest. Root uptake of 239,240 Pu by plants is extremely small, and plant contamination by resuspended soil is an important factor in considering the soil-to-plant transfer of this radionuclide. In spruce forest, more plutonium was transferred into plants when pollution load increased due to resuspension of litter particles, which contained higher concentrations of plutonium in the vicinity of the smelter. Soil-to-plant transfer of plutonium was much less affected in pine forests contaminated with industrial pollution. This research clearly indicates the sensitivity of the northern forest ecosystem to inorganic pollutants. Prediction of the soil-to-plant transfer of radionuclides in industrially polluted forest ecosystems requires detailed information on the total deposition, vertical distribution of radionuclides in soil, soil microbiological factors, other soil parameters as well as the rooting depths of the plants. (LN)

Forestry on the contamination territories

International Nuclear Information System (INIS)

Stavrov, A.I.; Kovalev, S.D.; Zhukovskaya, O.V.; Drobyshevskaya, N.M.

1995-01-01

The common characteristic of a contamination of the Belarus' forests by radionuclides after the Chernobyl accident is indicated. The recommendations for population about the picking up the mushrooms, berries, juices, medicinal herbs, preparation of forages, wood and other production in the contaminated forests are given. The information about the using of forests in depending on a level of the soil contamination is given. 5 refs., 1 tab., 4 figs

Contamination Event Detection with Multivariate Time-Series Data in Agricultural Water Monitoring

Directory of Open Access Journals (Sweden)

Yingchi Mao

2017-12-01

Full Text Available Time series data of multiple water quality parameters are obtained from the water sensor networks deployed in the agricultural water supply network. The accurate and efficient detection and warning of contamination events to prevent pollution from spreading is one of the most important issues when pollution occurs. In order to comprehensively reduce the event detection deviation, a spatial–temporal-based event detection approach with multivariate time-series data for water quality monitoring (M-STED was proposed. The M-STED approach includes three parts. The first part is that M-STED adopts a Rule K algorithm to select backbone nodes as the nodes in the CDS, and forward the sensed data of multiple water parameters. The second part is to determine the state of each backbone node with back propagation neural network models and the sequential Bayesian analysis in the current timestamp. The third part is to establish a spatial model with Bayesian networks to estimate the state of the backbones in the next timestamp and trace the “outlier” node to its neighborhoods to detect a contamination event. The experimental results indicate that the average detection rate is more than 80% with M-STED and the false detection rate is lower than 9%, respectively. The M-STED approach can improve the rate of detection by about 40% and reduce the false alarm rate by about 45%, compared with the event detection with a single water parameter algorithm, S-STED. Moreover, the proposed M-STED can exhibit better performance in terms of detection delay and scalability.

An assessment on the environmental contamination caused by the Fukushima accident.

Science.gov (United States)

Song, Jin Ho

2018-01-15

The radiological releases from the damaged fuel to the atmosphere and into the cooling water in the Fukushima Daiich Nuclear Power Plant (FDNPP) accident are investigated. Atmospheric releases to the land and ocean mostly occurred during the first week after the accident whereas continuous release from the damaged fuel into the cooling water resulted in an accumulation of contaminated water in the plant during last six years. An evaluation of measurement data and analytical model for the release of radionuclides indicated that atmospheric releases were mainly governed by the volatility of the radionuclides. Using the measurement data on the contaminated water, the mechanism for the release of long-lived radionuclides into the cooling water was analyzed. It was found that the radioactivity concentrations of 90 Sr in the contaminated water in the Primary Containment Vessel (PCV) of unit 2 and unit 3 were consistently higher than that of 137 Cs and the radioactivity concentration of 90 Sr in the turbine building of unit 1 in year 2015 was higher than that in year 2011. It was also observed that the radioactivity concentration of long-lived radionuclides in the contaminated water in the FDNPP is still high even in year 2015. The activity ratio of 238 Pu/ 239+240 Pu for the contaminated water was in the range of 1.7-5.4, which was significantly different from the ratios from the soil samples representing the atmospheric releases of FDNPP. It is concluded that the release mechanisms into the atmosphere and cooling water are clearly different and there has been significant amount of long-lived radionuclides released into the contaminated water. Copyright © 2017 Elsevier Ltd. All rights reserved.

Individual monitoring program for occupational exposures to radionuclides by inhalation

International Nuclear Information System (INIS)

Piechowski, J.; Menoux, B.

1985-01-01

Individual monitoring of exposure to radioactive products is carried out when there is a risk of significant internal contamination. In its publications 26 and 35 the International Commission on Radiological Protection has given recommendations on the monitoring programs. Besides, the metabolic models developed in publication 30 have allowed to establish retention and excretion functions for some radionuclides after intake by inhalation in the adult man. These have been published in the report CEA-R--5266. Considering these data and taking into account the practical problems that occur in the course of surveillance of workers, programs of individual monitoring for contamination by inhalation are proposed. These programs for routine and special monitoring have been developed for the most common radionuclides involved in the nuclear industry [fr

Sellafield waste radionuclides in Irish sea intertidal and salt marsh sediments.

Science.gov (United States)

Mackenzie, A B; Scott, R D

1993-09-01

Low level liquid radioactive waste discharges from the Sellafield nuclear fuel reprocessing plant in north west England had generated environmental inventories of about 3 × 10(16) Bq of(137)Cs, 6.8 × 10(14) Bq of(239,240)Pu and 8.9 × 10(14) Bq of(241)Am by 1990. Most of the(239,240)Pu and(241)Am and about 10% of the(137)Cs has been retained in a deposit of fine marine sediment close to the discharge point. The quantities of radionuclides discharged annually from Sellafield decreased by two orders of magnitude from the mid-1970s to 1990 but estimated critical group internal and external exposure decreased by less than one order of magnitude over this period. This indicates that during the period of reduced discharges, radionuclides already in the environment from previous releases continued to contribute to the critical group exposure and highlights the need to understand processes controlling the environmental distribution of the radionuclides.Redistribution of the contaminated marine sediment is potentially of major significance in this context, in particular if it results in transport of radionuclides to intertidal areas, where contact with the human population is relatively likely.A review is presented of published work relating to Sellafield waste radionuclides in Irish Sea sediments. Data on temporal and spatial trends in radionuclide concentrations and activity ratios are collated from a number of sources to show that the dominant mechanism of radionuclide supply to intertidal areas is by redistribution of the contaminated marine sediment. The implications of this mechanism of supply for trends in critical group radiation exposure are considered.

Ecological Role of Soils upon Radioactive Contamination

Science.gov (United States)

Tsvetnov, Evgeny; Shcheglov, Alexei; Tsvenova, Olga

2016-04-01

The ecological role of soils upon radioactive contamination is clearly manifested in the system of notions about ecosystems services, i.e., benefits gained by humans from ecosystems and their components, including soils (Millennium Ecosystem Assessment, 2005). For the soils, these services are considered on the basis of soil functions in the biosphere that belong to the protective ecosystem functions within the group of soil functions known under the names of "Buffer and protective biogeocenotic shield" (at the level of particular biogeocenoses) and "Protective shield of the biosphere" (at the global biospheric level) (according to Dobrovol'skii & Nikitin, 2005). With respect to radionuclides, this group includes (1) the depositing function, i.e., the accumulation and long-term sequestration of radioactive substances by the soil after atmospheric fallout; (2) the geochemical function, i.e., the regulation of horizontal and vertical fluxes of radionuclides in the system of geochemically conjugated landscapes and in the soil-groundwater and soil-plant systems; and (3) the dose-forming function that is manifested by the shielding capacity of the soil with respect to the external ionizing radiation (lowering of the dose from external radiation) and by the regulation of the migration of radionuclides in the trophic chain (lowering of the dose from internal radiation). The depositing and geochemical functions of the soils are interrelated, which is seen from quantitative estimates of the dynamics of the fluxes of radionuclides in the considered systems (soil-plant, soil-groundwater, etc.). The downward migration of radionuclides into the lower soil layers proceeds very slowly: for decades, more than 90% of the pool of radionuclides is stored in the topmost 10 cm of the soil profile. In the first 3-5 years after the fallout, the downward migration of radionuclides with infiltrating water flows decreases from several percent to decimals and hundredths of percent from the

Peace programme for evaluating the impact of accidents contaminating the environment

Energy Technology Data Exchange (ETDEWEB)

Brechignac, F.; Vallejo, R.; Sauras, T.; Casadesus, J.; Thiry, Y.; Waegeneers, N.; Forsberg, S.; Shaw, G.; Madoz-Escande, C.; Gonze, M.A. [CEA/Fontenay-aux-Roses, Inst. de Protection et de Surete Nucleaire, IPSN, 92 (France)

2000-07-01

The Chernobyl accident, which led to substantial release of radioactive materials in the atmosphere, demonstrated that large environmental areas may be contaminated by fall-out deposition of radioactivity. In particular, contamination by Cs and Sr of agro-ecosystems where food production is taking place is most susceptible to contribute to population radiation dose. Nuclear safety analysis shows that, although very small, the probability of an accident occurring on a pressurized water reactor (PWR) cannot be completely set aside. In such a situation, decision making and management of the contaminated agricultural surfaces largely depend on our ability to predict how, and to which extent, the initial contamination may lead to polluted foodstuffs. Furthermore, the efficiency of the prediction models relies on our level of understanding of the mechanisms governing the transfer of radionuclides in the soil-plant system. Unraveling these mechanisms from in situ observations of environmental areas contaminated by past events is difficult due to the lack of control on both, the contamination itself, which happened in a critical situation, and the natural environment, which is highly variable, temporally and spatially. Such conditions prevent a clear identification of the most relevant parameters influencing the radionuclides transfer and thereby the prediction goal. In particular, current transfer factors introduced in prediction models suffer from unresolved and poorly documented variabilities. This is why IPSN developed a unique research facility capable of generating, in closed and controlled environmental conditions, a mini-accident with release of radioactive aerosols on small-scale, but realistic, samples of crops. These crops are conducted on undisturbed soil monoliths, featuring several soil types from various European countries, managed in lysimeters with advanced water movement control, and placed in greenhouses where three typical climates can be reproduced

Peace programme for evaluating the impact of accidents contaminating the environment

International Nuclear Information System (INIS)

Brechignac, F.; Vallejo, R.; Sauras, T.; Casadesus, J.; Thiry, Y.; Waegeneers, N.; Forsberg, S.; Shaw, G.; Madoz-Escande, C.; Gonze, M.A.

2000-01-01

The Chernobyl accident, which led to substantial release of radioactive materials in the atmosphere, demonstrated that large environmental areas may be contaminated by fall-out deposition of radioactivity. In particular, contamination by Cs and Sr of agro-ecosystems where food production is taking place is most susceptible to contribute to population radiation dose. Nuclear safety analysis shows that, although very small, the probability of an accident occurring on a pressurized water reactor (PWR) cannot be completely set aside. In such a situation, decision making and management of the contaminated agricultural surfaces largely depend on our ability to predict how, and to which extent, the initial contamination may lead to polluted foodstuffs. Furthermore, the efficiency of the prediction models relies on our level of understanding of the mechanisms governing the transfer of radionuclides in the soil-plant system. Unraveling these mechanisms from in situ observations of environmental areas contaminated by past events is difficult due to the lack of control on both, the contamination itself, which happened in a critical situation, and the natural environment, which is highly variable, temporally and spatially. Such conditions prevent a clear identification of the most relevant parameters influencing the radionuclides transfer and thereby the prediction goal. In particular, current transfer factors introduced in prediction models suffer from unresolved and poorly documented variabilities. This is why IPSN developed a unique research facility capable of generating, in closed and controlled environmental conditions, a mini-accident with release of radioactive aerosols on small-scale, but realistic, samples of crops. These crops are conducted on undisturbed soil monoliths, featuring several soil types from various European countries, managed in lysimeters with advanced water movement control, and placed in greenhouses where three typical climates can be reproduced

Mobility of Source Zone Heavy Metals and Radionuclides: The Mixed Roles of Fermentative Activity on Fate and Transport of U and Cr. Final Report

Energy Technology Data Exchange (ETDEWEB)

Gerlach, Robin [Montana State Univ., Bozeman, MT (United States); Peyton, Brent M. [Montana State Univ., Bozeman, MT (United States); Apel, William A. [Idaho National Lab., Idaho Falls, ID (United States)

2014-01-29

Various U. S. Department of Energy (DOE) low and medium-level radioactive waste sites contain mixtures of heavy metals, radionuclides and assorted organic materials. In addition, there are numerous sites around the world that are contaminated with a mixture of organic and inorganic contaminants. In most sites, over time, water infiltrates the wastes, and releases metals, radionuclides and other contaminants causing transport into the surrounding environment. We investigated the role of fermentative microorganisms in such sites that may control metal, radionuclide and organics migration from source zones. The project was initiated based on the following overarching hypothesis: Metals, radionuclides and other contaminants can be mobilized by infiltration of water into waste storage sites. Microbial communities of lignocellulose degrading and fermenting microorganisms present in the subsurface of contaminated DOE sites can significantly impact migration by directly reducing and immobilizing metals and radionuclides while degrading complex organic matter to low molecular weight organic compounds. These low molecular weight organic acids and alcohols can increase metal and radionuclide mobility by chelation (i.e., certain organic acids) or decrease mobility by stimulating respiratory metal reducing microorganisms. We demonstrated that fermentative organisms capable of affecting the fate of Cr6+, U6+ and trinitrotoluene can be isolated from organic-rich low level waste sites as well as from less organic rich subsurface environments. The mechanisms, pathways and extent of contaminant transformation depend on a variety of factors related to the type of organisms present, the aqueous chemistry as well as the geochemistry and mineralogy. This work provides observations and quantitative data across multiple scales that identify and predict the coupled effects of fermentative carbon and electron flow on the transport of radionuclides, heavy metals and organic contaminants in

Mobility of Source Zone Heavy Metals and Radionuclides: The Mixed Roles of Fermentative Activity on Fate and Transport of U and Cr. Final Report

International Nuclear Information System (INIS)

Gerlach, Robin; Peyton, Brent M.; Apel, William A.

2014-01-01

Various U. S. Department of Energy (DOE) low and medium-level radioactive waste sites contain mixtures of heavy metals, radionuclides and assorted organic materials. In addition, there are numerous sites around the world that are contaminated with a mixture of organic and inorganic contaminants. In most sites, over time, water infiltrates the wastes, and releases metals, radionuclides and other contaminants causing transport into the surrounding environment. We investigated the role of fermentative microorganisms in such sites that may control metal, radionuclide and organics migration from source zones. The project was initiated based on the following overarching hypothesis: Metals, radionuclides and other contaminants can be mobilized by infiltration of water into waste storage sites. Microbial communities of lignocellulose degrading and fermenting microorganisms present in the subsurface of contaminated DOE sites can significantly impact migration by directly reducing and immobilizing metals and radionuclides while degrading complex organic matter to low molecular weight organic compounds. These low molecular weight organic acids and alcohols can increase metal and radionuclide mobility by chelation (i.e., certain organic acids) or decrease mobility by stimulating respiratory metal reducing microorganisms. We demonstrated that fermentative organisms capable of affecting the fate of Cr6+, U6+ and trinitrotoluene can be isolated from organic-rich low level waste sites as well as from less organic rich subsurface environments. The mechanisms, pathways and extent of contaminant transformation depend on a variety of factors related to the type of organisms present, the aqueous chemistry as well as the geochemistry and mineralogy. This work provides observations and quantitative data across multiple scales that identify and predict the coupled effects of fermentative carbon and electron flow on the transport of radionuclides, heavy metals and organic contaminants in

The effects of the marine biosphere and hydrosphere upon the specific activity of contaminant radionuclides

International Nuclear Information System (INIS)

Lowman, F.G.

1969-01-01

Fusion and fission products as well as neutron induced radionuclides will be produced by the use of nuclear explosives for excavation. Stable elements from the geological matrix which are vaporized at the time of detonation will be vented in the same form as the radionuclides and will dilute the radionuclides to different specific activities depending upon the yield and design of the explosive, the neutron flux, neutron cross-sections for the stable elements and the homogeneity of the rock. Radionuclides in the cloud and fallout may be further diluted by pulverized rock on which they plate although the chemical forms may or may not be the same. This fallout material may be deposited into the sea and will react with sea water and its contained salts to precipitate or co-precipitate some radionuclides and release others as colloids or solutes where they will be subject to further dilution by the stable elements in sea water. The radionuclides will be subjected to varying amounts of physical and chemical dilution according to the physical environmental parameters. In some estuarine and upwelling areas of high biological productivity, the radionuclides and corresponding stable elements may become incorporated into cycles involving the biosphere, hydrosphere and bottom sediments in which the added material will remain in the area for longer periods of time than that expected from physical mixing and dilution. (author)

The effects of the marine biosphere and hydrosphere upon the specific activity of contaminant radionuclides

Energy Technology Data Exchange (ETDEWEB)

Lowman, F G [Puerto Rico Nuclear Center, Mayaguez (Puerto Rico)

1969-07-01

Fusion and fission products as well as neutron induced radionuclides will be produced by the use of nuclear explosives for excavation. Stable elements from the geological matrix which are vaporized at the time of detonation will be vented in the same form as the radionuclides and will dilute the radionuclides to different specific activities depending upon the yield and design of the explosive, the neutron flux, neutron cross-sections for the stable elements and the homogeneity of the rock. Radionuclides in the cloud and fallout may be further diluted by pulverized rock on which they plate although the chemical forms may or may not be the same. This fallout material may be deposited into the sea and will react with sea water and its contained salts to precipitate or co-precipitate some radionuclides and release others as colloids or solutes where they will be subject to further dilution by the stable elements in sea water. The radionuclides will be subjected to varying amounts of physical and chemical dilution according to the physical environmental parameters. In some estuarine and upwelling areas of high biological productivity, the radionuclides and corresponding stable elements may become incorporated into cycles involving the biosphere, hydrosphere and bottom sediments in which the added material will remain in the area for longer periods of time than that expected from physical mixing and dilution. (author)

Recent research involving the transfer of radionuclides to milk

International Nuclear Information System (INIS)

Ward, G.M.

1989-01-01

The radionuclides in milk, which result from exposure of dairy cows to radioactive fallout, are a major factor in assessment of internal radiation of humans. To evaluate the radionuclide intake of people from fallout-contaminated milk requires information about feed sources and milk distribution. Pasture intake and the shelf-life of milk are important factors in the case of a short-lived radionuclide like 131 I. Large-scale human radiation assessment studies are underway, all of which consider the dairy food chain as a critical component. These include retrospective studies of fallout from nuclear weapons testing at the Nevada site in the 1950s and the impact of the Chernobyl accident on April 26, 1986

Fluvial export of radionuclides: impact on sediment storages of the Rhone River and fluxes towards the Mediterranean Sea

International Nuclear Information System (INIS)

Rolland, B.

2006-02-01

This study deals with the behaviour of trace contaminants originating from chronic liquid releases within fluvial aquatic systems. It focuses on some particle reactive artificial radionuclides that were released by the Marcoule nuclear fuel reprocessing plant during several years mainly prior the end of the nineties and that are still detected in the lower Rhone river. It underlines the decrease of 137 Cs, 238 Pu and 239+240 Pu fluxes to the Mediterranean Sea in relation with the variations in the chronic liquid releases from Marcoule. The role of flood events on radionuclides exports processes is particularly considered. Over the years 2002 to 2004, floods contributed for 67%, 55%, 68%, 49% and 56% of the mean annual fluxes of 137 Cs, 238 Pu and 239+240 Pu and natural 7 Be et 210 Pbxs, although these events only represented 5% of time. The removal, during floods, of sediments contaminated by the Marcoule releases contributes on the average for 19%, 44% and 22% of the annual exports of 137 Cs, 238 Pu and 239+240 Pu towards the Sea. Thus, such sedimentary stocks act as a delayed source term of artificial radioactivity that is currently significant. Determination of the sediments residence times before removal allows to evaluate the Rhone capacity to clear its contaminated stocks. Residence times of 200 years, 100 years and 900 years are estimated to be necessary to totally remove the accumulated 137 Cs, 238 Pu and 239+240 Pu, respectively. The location typologies of sediment storages within fluvial systems are also specified. These location are represented on one hand by dams, and on the other hand by river banks and oxbow lakes. Stocks accumulated in dams seem to be removed more easily than those trapped in banks. (author)

Microbial Mineral Transformations at the Fe(II)/Fe(III) Redox Boundary for Solid Phase Capture of Strontium and Other Metal/Radionuclide Contaminants

International Nuclear Information System (INIS)

Ferris, F.G.; Roden, E.E.

2000-01-01

The migration of 90 Sr in groundwater is a significant environmental concern at former nuclear weapons production sites in the US and abroad. Although retardation of 90 Sr transport relative to mean groundwater velocity is known to occur in contaminated aquifers, Sr 2+ does not sorb as strongly to iron oxides and other mineral phases as do other metal-radionuclides contaminants. Thus, some potential exists for extensive 90 Sr migration from sources of contamination. Chemical or biological processes capable of retarding or immobilizing Sr 2+ in groundwater environments are of interest from the standpoint of understanding controls on subsurface Sr 2+ migration. In addition, it may be possible to exploit such processes for remediation of subsurface Sr contamination. In this study the authors examined the potential for the solid phase sorption and incorporation of Sr 2+ into carbonate minerals formed during microbial Fe(III) oxide reduction as a first step toward evaluating whether this process could be used to promote retardation of 90 Sr migrations in anaerobic subsurface environments. The demonstration of Sr 2+ capture in carbonate mineral phases formed during bacterial HFO reduction and urea hydrolysis suggests that microbial carbonate mineral formation could contribute to Sr 2+ retardation in groundwater environments. This process may also provide a mechanism for subsurface remediation of Sr 2+ and other divalent metal contaminants that form insoluble carbonate precipitates

Accumulation of 137Cs and 90Sr radionuclides by leguminous plants of various species and varieties

International Nuclear Information System (INIS)

Zhdanovich, V.P.; Podolyak, A.G.; Arastovich, T.V.; Demidovich, S.A.; Odintsova, L.E.; Ivashkova, I.I.; Polovkov, N.N.

2005-01-01

Decision of protein problem on territories contaminated with radionuclides as a result of the accident at the Chernobyl NPP is not possible without extension of lands under cultivation of leguminous plants (peas, lupine and soybean). All lupine varieties show high indices of radionuclides accumulation and are restrictedly acceptable for production on contaminated territories. The following varieties of yellow forage lupine are the most acceptable for cultivation on the contaminated territories: Zhemchug, Rannij, Adradzhenne, Mitan. Introduction of varieties with the low level of radionuclides accumulation (peas — Aist, Agat, Gomelskaya; soybean — Mageva, Pina, Severnaya zvezda) into agricultural production will make to possible to obtain agricultural products meeting the requirements of the “Republican permissible levels of 137Cs and 90Sr content in agricultural raw materials and forages” on arable lands with the higher density of radioactive contamination: 137Cs — 925—1110 kBq/m2 (25-30 Ci/km2) and 90Sr 15—18 kBq/m2 (0.40-0.50 Ci/km2)

Maximum values and classifications of radionuclides

International Nuclear Information System (INIS)

1993-01-01

The primary means of controlling the use of radiation are safety license procedure and the monitoring of radiation exposure and working conditions at places of radiation use. In Section 17 of the Finnish Radiation Act (592/91) certain operations are exempted from the safety license. The exemption limits for the licensing of radioactive materials, the radiotoxicity classification of radionuclides related to such exemption limits, the annual limits on intake of radionuclides to be followed when monitoring internal radiation dose, as well as concentration limits in the breathing air are specified in the guide. Also the surface contamination limits which must be followed when monitoring working conditions at places of radiation use are presented. (4 refs., 6 tabs.)

Differential survival of mosquitofish exposed to radionuclides is dependent on RAPD genotype

International Nuclear Information System (INIS)

Theodorakis, C.W.; Shugart, L.R.

1995-01-01

In previous studies, it was found that certain RAPD (Randomly Amplified Polymorphic DNA) markers were present at higher frequencies in radionuclide-contaminated mosquitofish (Gambusia affinis) populations than in reference populations. These markers will be referred to as contaminant specific markers. In the present study, fish with and without these markers were collected from non-contaminated populations and exposed in situ to radionuclides by caging them in one of the contaminated sites. Forty fish were exposed for 1--6 weeks, after which the survivors were collected and DNA was extracted for genotypic analysis. In one experiment, the frequencies of contaminant specific markers in the survivors were compared to the frequencies of these markers in the native contaminated and uncontaminated (the source of the caged fish) populations. It was found that the genotypic distributions were more similar to the native contaminated population. In another experiment, samples of caudal fin tissue were collected for DNA extraction before and after placing fish in the cages, in order to compare survival rates of different genotypes. It was found that fish with the contaminant indicative bands had higher percent survival than the other fish. Experiments are underway or are being planned in order to determine the molecular identity of these bands and the ecological significance of altered band frequencies in hopes of developing population-level biomarkers of contaminant exposure and ecological affects

Intercomparison measurements of surface soil contamination with in-situ gamma ray spectrometry. Pt.1. Artificial radionuclides

International Nuclear Information System (INIS)

Winkelmann, I.

1994-01-01

This intercomparison program was performed by the Federal Office of Radiation Protection in October 1993. It includes seven laboratory teams from five countries and is applied on a pasture in southern Germany having an undisturbed soil profile. The location was chosen because of its relatively high 137 Cs-soil contamination caused by the Chernobyl accident - up to 50 kBq/m 2 . The deposition of 134 Cs and 137 Cs was determined. The comparison demonstrated a good agreement between results from different labs. Additionally, the dose rate at all marked locations was measured and compared to the dose rate of individual radionuclides calculated from the measured spectra. A relatively good agreement was obtained. It is shown that the main contribution to the total dose rate of 70 nSv/h is made by 137 Cs with a value of 5 nSv/h. 4 figs., 2 tabs., 3 refs. (orig.)

Fluxes of radionuclides in the agricultural production after a nuclear accident: countermeasures and decontamination techniques

International Nuclear Information System (INIS)

Jouve, A.

1997-01-01

This thesis deals with the radiological consequences of a nuclear accident through the radioactive contamination of the food chain and the subsequent countermeasures for decreasing the fluxes of radionuclides and decontaminating agricultural lands. After a brief summary of the radioprotection ground and context in case of a nuclear accident, this work surveys existing data on the fluxes of radionuclides in soils and from soil to plants. The research work focuses on both the prediction of the fluxes of radionuclides and possible countermeasures: the measurement of the bioavailability of radionuclides in the soil solution, its use in a mathematical expression to quantify the soil-to-plant transfer of caesium and strontium, and the perspectives of an innovative technique of soil decontamination. The obtained results show that based on 4 coefficients, it is possible to predict crop contamination within a 3 % confidence interval: the fluid solid distribution coefficient of radionuclides kd, the amount of chemical analogues of caesium and strontium, i.e. potassium and calcium, respectively, soil pH and a constant characterising the plant species that is concerned. However, it generally appears from soil to plant transfer studies that the reduction of the fluxes of radionuclides is not a promising way of radiological exposure mitigation after a nuclear accident. The work performed shows that it is more efficient to tackle the source of the contamination, i.e. decontaminate the soil. The proposed technique of soil scraping using a turf harvester appears to be the most advantageous among the tested options, for the decontamination of peat-bog meadows. (author)

Radionuclides contribution of emergency NPP 'Fukushima-1' in the contamination of the Sakhalin Island soils

Energy Technology Data Exchange (ETDEWEB)

Molchanova, I.V.; Mikhailovskaya, L.N.; Pozolotina, V.N.; Antonova, E.V. [Institute of Plant and Animal Ecology, Ural Division, Russian Academy of Sciences (Russian Federation); Zhuravlev, Yu.N.; Timofeeva, Ya.O.; Burdukovskii, M.L. [Institute of Biology and Soil Science, Far East Branch, Russian Academy of Sciences (Russian Federation)

2014-07-01

The Russian Far East is of special interest for radioecology because of the Fukushima-1 NPP accident occurred in close vicinity of this region. We evaluated the contents of man-made radionuclides, heavy metals and the contribution of the accident fallouts of {sup 137}Cs into contamination of the soil-plant covers in the coastal zone of the Myravyov-Amyrsky Peninsula and the territory of the Island Sakhalin. This contribution was assessed with use specific activity of {sup 134}Cs and ratio {sup 134}Cs/{sup 137}Cs. The generally-accepted methods of the radioecological investigations were used for sampling. The leaf fall, forest litters, and soils were sampling from the profile cuts of layer by layer, up to 20 cm. The artificial radionuclides ({sup 90}Sr, {sup 134,137}Cs and {sup 239,240}Pu), heavy metals and microelements (Co, Cu, Zn, Pb and Mn) contents in the prepared samples were determined. Analysis of samples has shown that the contents of {sup 90}Sr and {sup 137}Cs in 0-20 cm layer of the soils of test plots doesn't depend from the place of their situated and vary from 300 to 1500 Bk/m{sup 2} for {sup 90}Sr and from 500 to 4000 Bk/m{sup 2} for {sup 137}Cs. The presence in investigated samples of {sup 134}Cs indicates to contribution of accidental fallout of Fukushima-1 into contamination of the components of the natural ecosystems. Taking into account the contents of {sup 134}Cs and the {sup 134}Cs/{sup 137}Cs ratio in the gas-aerosol fallout (at the time of the accident it was almost equal) we calculated amounts of {sup 137}Cs that contaminated the different areas of Far-Eastern region. The results are in the range 70-300 Bq/m{sup 2}, which is higher than that at the Urals and Siberia territories (1.0-40.0 Bq/m{sup 2}). The contents of {sup 239,240}Pu in samples collected in the coastal zone of the Myravyov-Amyrsky Peninsula vary from 20 to 60 Bq/m{sup 2} and the ratio {sup 238}Pu/{sup 239,240}Pu is on the average 0.04. Similar levels of contamination

Influence of radioactive contamination to agricultural products due to dry and wet deposition processes during a nuclear emergency

International Nuclear Information System (INIS)

Hwang, Won Tae; Kim, Eun Han; Suh, Kyung Suk; Han, Moon Hee; Choi, Yong Ho; Lee, Chang Woo

2002-01-01

Combined with deposition model onto the ground of radionuclides, the influence of radioactive contamination to agricultural products was analyzed due to wet deposition as well as dry deposition from radioactive air concentration during a nuclear emergency. The previous dynamic food chain model, in which initial input parameter is only radionuclide concentrations on the ground, was improved for the evaluating of radioactive contamination to agricultural products from either radionuclide concentrations in air or radionuclide concentrations on the ground. As the results, in case of deposition onto the ground, wet deposition was more dominant process than dry deposition. While the contamination levels of agricultural products were dependent on the a variety of factors such as radionuclides and rainfall rate. It means that the contamination levels of agricultural products are determined from which is more dominant process between deposition on the ground and interception onto agricultural plants

A model for evaluating the radioactive contamination in the urban environment

International Nuclear Information System (INIS)

Hwang, Won Tae; Kim, Eun Han; Jeong, Hyo Joon; Suh, Kyung Suk; Han, Moon Hee

2005-01-01

A model for evaluating radioactive contamination in the urban environment, named METRO-K, was developed as a basic step for accident consequence analysis in case of an accidental release. The three kind of radionuclides ( 137 Cs, 106 Ru, 131 I) and the different chemical forms of iodine (particulate, organic and elemental forms) are considered in the model. The radioactive concentrations are evaluated for the five types of surface (roof, paved road, wall, lawn/soil, tree) as a function of time. Using the model, the contaminative impacts of the surfaces were intensively investigated with respect to with and without precipitation during the measurement periods of radionuclides in air. In addition, a practical application study was conducted using 137 Cs concentration in air and precipitation measured in an European country at the Chernobyl accident. As a result, precipitation was an influential factor in surface contamination. The degree of contamination was strongly dependent on the types of radionuclide and surface. Precipitation was more influential in contamination of 137 Cs than that of 131 I (elemental form)

Problems of dynamics radionuclides behavior in environment of Belarus

International Nuclear Information System (INIS)

Basharin, A.V.; Matveev, S.A.; Pushkareva, T.L.; Sharovarov, G.A.

2003-01-01

The experience of various methods application for radionuclide contaminated objects after the Chernobyl accident is considered. Methods useful to different objects, including kindergartens, are defined as a result of analysis. Methods of observation and control 134,137 Cs, 90 Sr and 238-240 Pu behavior in various environments are described. Value of the second air pollution after extraordinary situation at contaminated territories and object 'Ukryttia' is given. Dates of post-Chernobyl contamination of rivers and soils with radiocesium and radiostrontium, as well as deactivation of social objects are generalized

Multimedia contaminant environmental exposure assessment methodology as applied to Los Alamos, New Mexico

International Nuclear Information System (INIS)

Whelan, G.; Thompson, F.L.; Yabusaki, S.B.

1983-02-01

The MCEA (Multimedia Contaminant Environmental Exposure Assessment) methodology assesses exposures to air, water, soil, and plants from contaminants released into the environment by simulating dominant mechanisms of contaminant migration and fate. The methodology encompasses five different pathways (i.e., atmospheric, terrestrial, overland, subsurface, and surface water) and combines them into a highly flexible tool. The flexibility of the MCEA methodology is demonstrated by encompassing two of the pathways (i.e., overland and surface water) into an effective tool for simulating the migration and fate of radionuclides released into the Los Alamos, New Mexico region. The study revealed that: (a) the 239 Pu inventory in lower Los Alamos Canyon increased by approximately 1.1 times for the 50-y flood event; (b) the average contaminant 239 Pu concentrations (i.e., weighted according to the depth of the respective bed layer) in lower Los Alamos Canyon for the 50-y flood event decreased by 5.4%; (c) approx. 27% of the total 239 Pu contamination resuspended from the entire bed (based on the assumed cross sections) for the 50-y flood event originated from lower Pueblo Canyon; (d) an increase in the 239 Pu contamination of the bed followed the general deposition patterns experienced by the sediment in Pueblo-lower Los Alamos Canyon; likewise, a decrease in the 239 Pu contamination of the bed followed general sediment resuspension patterns in the canyon; (e) 55% of the 239 Pu reaching the San Ildefonso Pueblo in lower Los Alamos Canyon originated from lower Los Alamos Canyon; and (f) 56% of the 239 Pu contamination reaching the San Ildefonso Pueblo in lower Los Alamos Canyon was carried through towards the Rio Grande. 47 references, 41 figures, 29 tables

Characterization of freshwater mosses as indicators of radioactive contamination; Caracterisation de mousses dulcaquicoles comme indicateurs de contamination radioactive

Energy Technology Data Exchange (ETDEWEB)

Beaugelin-Seiller, K

1994-12-16

The necessity of indicators of freshwater contamination has developed the interest for aquatic mosses. From a fundamental point of view, studying the influence of some biotic and abiotic factors has permitted to better know the mechanisms of radionuclides accumulation by these bryophytes. From a radioecological point of view, simulating real cases of water contamination has allowed to give results a very interesting representativeness. The use of mosses as bio-indicators was applied for two in situ experiments, the results of which have been interpreted from those obtained in laboratory. Finally, an approach by a mathematical model has showed that it is possible to have, in a middle term, an evaluation tool of freshwater contamination, based on the radionuclides concentrations measured in aquatic mosses. (author). refs., 57 figs., 24 tabs.