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1

Optimization of 210Po determination in soil

Szaciłowski Grzegorz, Dymecka Małgorzata, Prusińska Maria, Rzemek Katarzyna, Ośko Jakub, Mądry Magdalena, Kostecka Michalina, Araszkiewicz Agnieszka

Nukleonika

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2021

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Vol. 66, No. 2

75--79

EN

In recent years, naturally occurring radioactive materials (NORM) have become an important topic from the perspective of environmental protection. The list of isotopes that should be monitored in the environment is constantly growing as new amendments to international legislation are introduced. One of the often studied NORM elements is 210Po. In this study, a process of elaborating of a new method of 210Po determination in soil was presented. In the proposed method, several analytical aspects, like the influence of silica decomposition or optimization of an electrode material, were revised. The obtained procedure allows performance of complete radiochemical analysis in a single day, with the chemical efficiency of over 85% and great reduction of costs. Further, the influence of the use of phosphate fertilizers on polonium concentration in soil was also confirmed.

2

Natural radionuclides (NORM) in a Moroccan river affected by former conventional metal mining activities

Manjón Guillermo, Mantero Juan, Vioque Ignacio, Díaz-Francés Inmaculada, Galván José Antonio, Chakiri Said, Choukri Abdelmajid, García-Tenorio Rafael

Journal of Sustainable Mining

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2019

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Vol. 18, iss. 1

45--51

EN

The main aim of this work was to determine the levels of multiple natural radionuclides in an aquatic system (Moulouya river, Morocco) impacted by multiple abandoned Zinc and Lead mines. 238U, 234U, 232Th, 230Th and 210Po were determined by alpha-particle spectrometry in water and sediment samples collected along the river and in samples from three pit lakes of abandoned mines, located in the Upper Moulouya catchment area. The results enabled the analysis of the different levels of impact of former mining activities, depending on the natural radionuclides. While the activity concentration of U-isotopes in Moulouya river water was slightly elevated in the vicinity of abandoned mine wastes, other natural radionuclides (Th-isotopes and 210Po) levels were typical of a natural environment. This fact is clearly reflected in the magnitude and range observed in the distribution coefficients for the different radionuclides analyzed.

3

Long-term prediction of non-processed waste radioactivity of a niobium mine in Brazil

El Hajj Thammiris Mohamad, Gandolla Mauro Pietro Angelo, da Silva Paulo Sergio Cardoso, Torquato Henrique, Delboni Homero Junior

Journal of Sustainable Mining

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2019

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Vol. 18, iss. 3

142--149

EN

This work analyzed samples from a niobium mine in Brazil which produces massive quantities of non-processed waste (NPW) each year. Due to concerns about the environmental impact of stacking up this material in the long-term, investigations have had been made to evaluate its re-use options. Nevertheless, there are no regulations from the Brazilian National Commission of Nuclear Energy about commercializing this sub-product which has highly variable radiological activity because of the different lithologies present in the mine. Thus, the activity concentrations of 238U, 232Th, 226Ra, 228Ra, 228Th and 40K of the naturally radioactive ore (53 boreholes) and of the NPW (8 samples) were measured. Radiological hazard indices, radium equivalent, internal and external hazard and their equivalent doses were also calculated. Moreover, the X-ray diffraction, depth and coordinates of all samples were used to identify radioactive prone areas in the mine. For the NPW samples, the activity concentrations (in Bq/kg) were, on average, 64.9 of 238U, 104.8 of 226Ra, 1813.9 of 232Th, 1292.2 of 228Th, 1224.3 of 228Ra and 1184.2 of 40K. The analysis showed great variability between samples and the results can be used to evaluate possible uses such as building materials or foundation for roadbeds.

4

Discharges of dust from NORM facilities: Key parameters to assess effective doses for public exposure

Kunze Christian, Schulz Hartmut, Ettenhuber Eckard, Schellenberger Astrid, Dilling Jorg

Journal of Sustainable Mining

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2019

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Vol. 18, iss. 1

31--37

EN

In transposing Directive 2013/59/Euratom (European Basic Safety Standards or EU BSS) into national law, it was necessary to identify industrial sectors which involve naturally occurring radioactive materials (NORM) which may lead to public exposure that cannot be disregarded from a radiation protection point of view. A research project was implemented that resulted in a comprehensive survey of all potentially relevant industrial sectors operating in Germany. Major efforts were made to determine source terms of airborne discharges, atmospheric dispersion models, and dose calculations. The study arrived at the conclusion that the discharge and the settlement of dust in agricultural and horticultural areas is the most relevant dispersion and exposure pathway, while discharges of radon are of minor importance. The original study used a number of rather complex models that may distract from the fact that very few key parameters and assumptions determine the effective dose of members of the public. This paper revisits the study and identifies those parameters and assumptions and provides a simplified, generic, yet sufficiently reliable and robust assessment methodology to determine the radiological relevance of dust discharges from NORM industries under the typical geographical and meteorological conditions of Germany. This paper provides examples of dose estimates for members of the public for selected industries operating in Germany. Due to its simplicity and robustness, the methodology can also be used to assess effective doses resulting from discharges in other industries in Germany, and it can be adapted to conditions in other countries in a straightforward way.

5

The presence and dosimetry of radon and thoron in a historical, underground metalliferous mine

Kleinschmidt R., Watson D., Janik M., Gillmore G.

Journal of Sustainable Mining

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2018

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Vol. 17, iss. 3

120--130

EN

A combination of long term passive, and short term active radon-222, radon-220 and respective progeny measurements were conducted in both traverse and longitudinal axes of a historical metalliferous underground mine in North Queensland, Australia. While the passive monitor results provided average radon and thoron air concentrations over periods of 70-90 days, active measurements over a four day period provided significantly more detail into the dynamics of radon and progeny concentrations in the naturally ventilated mine environment. Passive monitor concentrations for radon and thoron ranged between 60 and 390 Bq m-3 (mean: 140 ±55 Bq m-3) and 140 and 2600 Bq m-3 (mean: 1070 ±510 Bq m-3) respectively, with passive thoron progeny monitors providing a mean concentration of 9 ±5 Bq m-3EEC. Active measurement mean concentrations for radon, thoron, radon progeny and thoron progeny in the centre of the mine drive were 130 ±90 Bq m-3, 300 ±100 Bq m-3, 20 ±20 Bq m-3EEC and 10 ±10 Bq m-3EEC respectively. It was identified that thoron passive detector placement is critical in establishing reliable monitoring data, and is the reason for the discrepancy between the active and passive thoron results in this study. Site specific progeny measurements are required for the accurate estimation of dose to persons entering the mine. Based on short term active measurements and passive thoron progeny monitor results, the dose contribution from thoron and progeny in the mine was observed to contribute up to 80% of the total radon/thoron inhalation dose, and therefore should not be underestimated in monitoring programs under similar conditions.

6

The radiological impact of NORM industries in the UK

Smith K., Warner Jones S., Oatway W., Jones J., Harvey M., Shaw P., Mobbs S.

Prace Naukowe GIG. Górnictwo i Środowisko / Główny Instytut Górnictwa

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2004

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nr 1

85-86

7

The inventory of Italian NORM concerned work activities in the frame of environment protection