Estimation of doses received in a dry-contaminated residential area in the Bryansk region, Russia, since the Chernobyl accident

Title: Estimation of doses received in a dry-contaminated residential area in the Bryansk region, Russia, since the Chernobyl accident

Author: K.G. Andersson, J. Roed

Reference: Journal of Environmental Radioactivity, Volume 85, Issues 2–3, 2006, Pages 228-240

DOI: http://dx.doi.org/10.1016/j.jenvrad.2004.08.019

Keywords: Radiation dose; Radiocaesium; Urban; Chernobyl; Preparedness; Dry deposition

Abstract: In nuclear preparedness, an essential requirement is the ability to adequately predict the likely consequences of a major accident situation. In this context it is very important to evaluate which contributions to dose are important, and which are not likely to have significance. As an example of this type of evaluation, a case study has been conducted to estimate the doses received over the first 17 years after the Chernobyl accident in a dry-contaminated residential area in the Bryansk region in Russia. Methodologies for estimation of doses received through nine different pathways, including contamination of streets, roofs, exterior walls, and landscape, are established, and best estimates are given for each of the dose contributions. Generally, contaminated soil areas were estimated to have given the highest dose contribution, but a number of other contributions to dose, e.g., from contaminated roofs and inhalation of contaminants during the passage of the contaminated plume, were of the same order of magnitude.

URL: http://www.sciencedirect.com/science/article/pii/S0265931X05002183

The use of weather radar in assessing deposition of radioactivity from chernobyl across England and Wales

Title: The use of weather radar in assessing deposition of radioactivity from chernobyl across England and Wales

Author: H.M. ApSimon, K.L. Simms, C.G. Collier

Reference: Atmospheric Environment (1967), Volume 22, Issue 9, 1988, Pages 1895-1900

DOI: http://dx.doi.org/10.1016/0004-6981(88)90078-9

Keywords: Wet deposition; weather radar; Chernobyl; nuclear accidents; ¹³⁷Cs

Abstract: Deposition of radionuclides from the Chernobyl accident depended critically on patterns of precipitation intercepting the material. This paper describes the use of the RAINPATCH model to calculate wet deposition of ¹³⁷Cs over England and Wales. This puff-based model makes direct use of precipitation data measured by weather radar to determine the scavenging of airborne material. The detailed spatial and temporal resolution of when and where material was scavenged provides good agreement with measurements. Since all the data used could potentially have been available at the time, such methods could usefully be applied in real time in the event of any future accident releasing such radionuclides.

URL: http://www.sciencedirect.com/science/article/pii/0004698188900789

Transfer of radiocesium from uncultivated soils to grass after the Chernobyl accident

Title: Transfer of radiocesium from uncultivated soils to grass after the Chernobyl accident

Author: Z. Pietrzak-Flis, P. Krajewski, G. Krajewska, N.R. Sunderland

Reference: Science of The Total Environment, Volume 141, Issues 1–3, 25 January 1994, Pages 147-153

DOI: http://dx.doi.org/10.1016/0048-9697(94)90024-8

Keywords: Radiocesium; Grass; Soil; Transfer factor; Chernobyl

Abstract: Transfer of radiocesium from uncultivated peat, loam and two sandy soils to grass in northeastern Poland was evaluated. Samples of grass and soil were collected from the same area of about 100 m² in the period from June 1988 to November 1991 twice a year. Grass was sampled from 1 m × 1 m squares by cutting to the plant base. Afterwards core samples of soil were taken from an area of 132.73 cm². ¹³⁴Cs, ¹³⁷Cs and ⁴⁰K were determined by gamma spectrometry. The average concentration of ¹³⁷Cs (to 10 cm depth) in the studied areas was in the range from 22.8 ± 2.5 Bq kg⁻¹ to 154.3 ± 13.7 Bq kg⁻¹. The average concentration of this radionuclide in grass varied from 6.76 ± 0.99 Bq kg⁻¹ dry weight (dry wt.) to 152.6 ± 37.4 Bq kg⁻¹ dry wt and depended upon the type of soil. The transfer of radiocesium to grass in the studied soils decreased in the following order: Sand I > peat > Sand II > loam. The results indicated that apart from soil, other parameters also influenced the transfer of radiocesium to grass. It has been found that ¹³⁴Cs from Chernobyl is more available to grass than ¹³⁷Cs from nuclear weapon tests.

URL: http://www.sciencedirect.com/science/article/pii/0048969794900248

Radiocesium in muscle tissue of reindeer and pike from northern Sweden before and after the Chernobyl accident. A retrospective study on tissue samples from the Swedish Environmental Specimen Bank

Title: Radiocesium in muscle tissue of reindeer and pike from northern Sweden before and after the Chernobyl accident. A retrospective study on tissue samples from the Swedish Environmental Specimen Bank

Author: Sevald Forberg, Tjelvar Odsjö, Mats Olsson

Reference: Science of The Total Environment, Volume 115, Issue 3, 30 April 1992, Pages 179-189

DOI: http://dx.doi.org/10.1016/0048-9697(92)90328-P

Keywords: radiocesium; reindeer; pike; Chernobyl; environmental specimen bank

Abstract: After the Chernobyl accident in April 1986, considerable deposition of radionuclides occurred regionally in eastern, central and northwestern Sweden. Locally, the fallout of radiocesium exceeded the remainder from atmospheric nuclear weapons tests by several magnitudes. Since the end of the 1960s samples of organs from various plant and animal species, annually collected at different localities, have been preserved in the Swedish Environmental Specimen Bank (ESB). In this work samples from the ESB have been used for retrospective studies of radioactive pollution. The activities of Cs-134 and Cs-137 in muscle tissues from reindeer, Rangifer tarandus, and pike, Esox lucius, preserved in the ESB, were measured. The samples were collected annually; the reindeer at three localities in northern Sweden and the pike at one of them. In material collected prior to the Chernobyl accident, the levels of Cs-137 were 57–180 Bq/kg in reindeer and 14–24 Bq/kg in pike, fresh weight basis. These levels relate to earlier nuclear bomb tests. A significant decrease was found in pike during the pre-Chernobyl period (1971–1986). In post-Chernobyl samples the burden of Cs-137 varied from amounts equal to the former levels in the northernmost locality and up to 80 times higher for the maximum values in the southernmost locality. The highest value recorded was 18 425 Bq/kg in reindeer. The geographic variations in reindeer from Chernobyl fallout were in accordance with the pattern of deposition estimated by aircraft surveys performed in May 1986. The ratio between ‘new’ and ‘old’ radiocesium burdens in pike, caught in 1987, approached the corresponding ratio for reindeer grazing in the precipitation area of the lake; 33 and 19, respectively.

URL: http://www.sciencedirect.com/science/article/pii/004896979290328P

The transport and fluvial redistribution of Chernobyl-derived radiocaesium within the River Wye basin, UK

title: The transport and fluvial redistribution of Chernobyl-derived radiocaesium within the River Wye basin, UK

Author: J.S. Rowan, D.E. Walling

Reference: Science of The Total Environment, Volume 121, 30 June 1992, Pages 109-131

DOI: http://dx.doi.org/10.1016/0048-9697(92)90310-O

Keywords: Wye; Chernobyl; radiocaesium; sediment-associated; redistribution

Abstract: Relatively little attention has been given to the long term prospect of fluvial transport processes redistributing Chernobyl-derived radiocaesium within the UK. Work undertaken within the Wye basin, central Wales, demonstrates a complex distribution of fallout at the catchment scale, with the bulk of the deposition concentrated in a narrow north-south band, situated in the west central areas of the basin, which contained in excess of 1500 Bq m⁻² of ¹³⁴Cs. Fluvial transport and redistribution of this material was demonstrated by river sampling during the winter of 1988/89, when the radiocaesium content of suspended sediment transported by the River Wye (≈ 30–50 mBq g⁻¹ of ¹³⁷Cs) remained 3–5-times higher than pre-Chernobyl levels. Floodplain reaches displayed variable levels of secondary contamination, dependent upon the upstream supply of radiocaesium and local morphological controls. Accordingly, the highest ¹³⁴Cs inventories within the basin (> 6000 Bq m⁻²) were associated with rapidly accreting floodplain sites. A number of these sites experienced only limited amounts of direct atmospheric fallout. The importance of fluvial redistribution as a secondary contamination mechanism is thus highlighted.

URL: http://www.sciencedirect.com/science/article/pii/004896979290310O

Transfer of radiocaesium in sensitive agricultural environments after the Chernobyl fallout in Sweden: III. County of Västernorrland

Title: Transfer of radiocaesium in sensitive agricultural environments after the Chernobyl fallout in Sweden: III. County of Västernorrland

Author: K. Rosén, E. Haak, Å. Eriksson

Reference: Science of The Total Environment, Volume 209, Issues 2–3, 19 January 1998, Pages 91-105

DOI: http://dx.doi.org/10.1016/S0048-9697(98)80100-9

Keywords: Radiocaesium; Radioiodine; Chernobyl; Nuclear fallout; Grass; Cereals

Abstract: In 1986 a large number of farms in the Chernobyl-affected area in the county of Västernorrland in northern Sweden were investigated for radiocaesium transfer to grass and cereal grain. The soil surface layer (0–5 cm) in 1986 and the crop products in 1986–1996 were analysed. The aim was to study the impact of soil and crop rotation on sensitivity of ¹³⁷Cs transfer in a short and long term perspective. In the fallout year 1986 the transfer to grass was usually much higher than to cereal grain. In this year the transfer to grass was usually much higher in the first cut rather than the second cut. The reduction in transfer with year was large but variable with site and with crop sequence. Ploughing was effective in decreasing the transfer of ¹³⁷Cs to crops. On arable sites in 1986 the transfer to cereal straw was larger at late stem elongation (LSE) than at the maturing stage. Unexpectedly, there was no clear relationship between transfer of ¹³⁷Cs to the crops and any of the soil characteristics. In 1986 the transfer of ¹³¹I to grass and cereals was also investigated on some of the farms. The results are compared with the transfer of ¹³⁷Cs, 2 months after the Chernobyl fallout.

URL: http://www.sciencedirect.com/science/article/pii/S0048969798801009

Transfer of radiocaesium in sensitive agricultural environments after the Chernobyl fallout in Sweden. II. Marginal and seminatural areas in the county of Jämtland

Title: Transfer of radiocaesium in sensitive agricultural environments after the Chernobyl fallout in Sweden. II. Marginal and seminatural areas in the county of Jämtland
Author: Klas Rosén
Reference: Science of The Total Environment, Volume 182, Issues 1–3, 5 April 1996, Pages 135-145

DOI: http://dx.doi.org/10.1016/0048-9697(95)05059-0

Keywords: Radiocaesium; Grass; Fallout; Chernobyl; Contamination

Abstract: In 1986, two Chernobyl-affected areas in the county of Jämtland, a mountain area and a river valley area, were investigated as to radiocaesium behaviour and transfer to grass. The soil surface layer (0–10 cm) in 1986 and 1989 and grass samples in 1986–1994 were analysed on 9 temporary grassland sites and 8 permanent pasture sites, described individually. The aim of this investigation was to study the sensitivity of different soil types and the influence of normal farming practices, ploughing and K-fertilization on the caesium transfer, in short- and long-term perspectives after the Chernobyl fallout. As expected, the transfer of ¹³⁷Cs to grass was usually higher on permanent pasture than on temporary grassland. For both types of grassland, however, there was a considerable but different change of transfer with years. The transfer to grass in the year of the fallout, 1986, depended to a large extent on the thickness and interception capacity of the grass sward. In the following years, it also depended on the caesium-fixing capacity to clay minerals, on K-fertilization and the reverse process of K removal by plant uptake. Ploughing down the contaminated surface layer and the mixing of caesium with mineral soil were effective in reducing the transfer. During the period 1986–1994, the transfer was reduced considerably, showing a range of (0.1–177.3 m²/kg d.w.) × 10⁻³. The calculated annual reduction halftime, T_ar, increased with years after fallout. It is clearly shown that both countermeasures, ploughing and K-fertilization, are of potential value to decrease grass contamination. Where both measures were employed a reduction in the range of 78%–95% was recorded in the year after ploughing.

URL: http://www.sciencedirect.com/science/article/pii/0048969795050590

Transfer of radiocaesium in sensitive agricultural environments after the Chernobyl fallout in Sweden. I. County of Gävleborg

Title: Transfer of radiocaesium in sensitive agricultural environments after the Chernobyl fallout in Sweden. I. County of Gävleborg

Author: Klas Rosén, Åke Eriksson, Enok Haak

Reference: Science of The Total Environment, Volume 182, Issues 1–3, 5 April 1996, Pages 117-133

DOI: http://dx.doi.org/10.1016/0048-9697(95)05056-6

Keywords: Radiocaesium; Chernobyl; Nuclear fallout; Cereals; Grass

Abstract: In 1986, 15 farms in the Chernobyl-affected area of the county of Gävleborg were investigated for radiocaesium transfer to grass and cereal grain. The soil surface layer (0–5 cm) in 1986 and the crop products in 1986–1994 were analysed. The aim was to study the impact of site and soil characteristics on sensitivity of ¹³⁷Cs transfer in a long-term perspective. The transfer was much higher to grass than to cereal grain. For both crop products, however, there was a considerable annual reduction. For grass, and especially in the fallout year 1986, the transfer depended on interception capacity of the stubble and grass sward, on soil fertility and K-fertilization as well as on dilution by crop growth. In the following years, the annual reduction in transfer to grass was reduced by a factor of 2 to 100. Both ploughing through the surface layer and the mixing of radiocaesium with soil contributed to a decreased transfer of radiocaesium to crops. Thick stubble and grass sward on the grassland sites was the main reason for a lag period of high persistent transfer. The annual reduction was less on organic than on mineral soils. Measures to decrease the transfer to crops are discussed in relation to a new concept to evaluate the long-term behaviour of ¹³⁷Cs in agricultural environments

URL: http://www.sciencedirect.com/science/article/pii/0048969795050566

Time-dependent behaviour of radiocaesium: A new method to compare the mobility of weapons test and Chernobyl derived fallout

Title: Time-dependent behaviour of radiocaesium: A new method to compare the mobility of weapons test and Chernobyl derived fallout

Author: J.T Smith, R.T Clarke, R Saxén

Reference: Journal of Environmental Radioactivity, Volume 49, Issue 1, May 2000, Pages 65-83

DOI: http://dx.doi.org/10.1016/S0265-931X(99)00088-0

Keywords: Radiocaesium; Kinetics; Chernobyl; Rivers; Mobility

Abstract: Environmental radiocaesium ( ) originates primarily from two sources, atmospheric nuclear weapons testing, and the Chernobyl accident. It has not, to our knowledge, previously been possible statistically to compare changes in the environmental mobility of from these two sources since the weapons test fallout varied in a complex manner over a number of years. A novel technique is presented for curve-fitting measurements with a time-dependent input function such as that for weapons test fallout. Different models were fitted to measurements of both pre- and post-Chernobyl activity concentrations in five major Finnish rivers. It was shown that there was no significant difference in the temporal changes in mobility from these two sources during the years after fallout. Transport parameters derived from weapons test measurements gave good predictions of the long-term contamination of these rivers by Chernobyl fallout. Changes in activity concentrations in rivers after Chernobyl have previously been shown to decline as a result of slow sorption to clay minerals in catchment soils. It is shown that weapons test fallout also exhibited this slow decline over time. Rates of decline in activity concentrations 10 years after fallout correspond to effective ecological half-lives (Teff) in the range 10–30 years. Removal of activity from the catchment was found to have no significant effect on the long-term decline in activity concentrations in these rivers.

Radiocaesium removal from European lakes and reservoirs: key processes determined from 16 Chernobyl-contaminated lakes

• Title: Radiocaesium removal from European lakes and reservoirs: key processes determined from 16 Chernobyl-contaminated lakes

Author: Smith, J.T. / Comans, R.N.J. / Elder, D.G.

Reference: Water Research, 33 (18), p.3762-3774, Dec 1999               

doi: 10.1016/S0043-1354(99)00087-1

Keywords: Chernobyl; radiocaesium; lake; distribution coefficient

Abstract: A study based on information from the scientific literature was carried out to identify the key processes which determine the initial radiocaesium activity concentration and its rate of removal in 16 different European lakes after the Chernobyl accident. Analysis and modelling of these data showed that a simple model, incorporating only dilution, lake flushing and settling of suspended particles, can explain 97% of the variation in initial activity concentrations in lakewater and 79% of the variation in ¹³⁷Cs removal rates.

URL: http://www.sciencedirect.com/science/article/pii/S0043135499000871