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Możliwości zastosowania uranowych wód kopalnianych jako alternatywnego źródła surowców i energii

Babka O., Harat A.

Archiwum Gospodarki Odpadami i Ochrony Środowiska

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2011

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Vol. 13, nr 3

29-36

PL

Wydobycie uranu było aż do połowy lat dziewięćdziesiątych ubiegłego wieku było jedną z najważniejszych gałęzi przemysłu byłej Czechosłowacji. Czechosłowację klasyfikowano wówczas pod względem wytwarzania koncentratu uranowego na 7 miejscu na świecie. W okresie od 1945 roku do połowy lat dziewięćdziesiątych XX wieku wydobyto łącznie 110 000 t uranu. W chwili obecnej podziemne wydobycie uranu prowadzone jest tylko ze złoża Rozna. Z eksploatację złóż związany jest napływ do wyrobisk górniczych wód kopalnianych. Ponad 10 lat po zakończeniu eksploatacji reżim hydrogeologiczny panujący w tych złożach stał się stabilny, a przeprowadzone analizy wykazały, iż wody kopalniane stanowić mogą źródło pozyskiwania surowców, ze względu na dużą ilość i znaczne stężenia substancji rozpuszczonych (np. Uran). Na terenach górniczych panują idealne warunki środowiskowe dla wód ciepłych, które znajdują się wystarczająco głęboko aby zapewnić ich ilościową i jakościową stabilność. Duże stężenie substancji rozpuszczonych sprawia, iż wody kopalniane mogą stanowić dodatkowe źródło uranu i innych substancji, jak również mogą być zastosowane jako alternatywne źródło energii.

EN

Uranium mining was one of the most important industry branches in the former Czechoslovak Republic up to the mid 1990's. The Czechoslovak Republic was ranked the 7th in the world in production of uranium concentrate. Overall, there were 110 000 tons of uranium extracted during period from 1945 to the mid 1990's. Currently, the underground mining of uranium is carried out only in the uranium mine Rozna. Exploitation of minerals is accompanied by the outflow of underground waters into mine excavations. The hydro geological regime of these deposits has become stable more than 10 years after the exploitation end and the results gained by the hydro geological surveys have shown that the waters in flooded mines may present a significant secondary source of raw materials due to their volume and concentrations of dissolved substances (e.g., uranium). Mining areas are also an ideal retention environment for warm water as they are deep enough to ensure the water qualitative and quantitative stability. This paper deals with the mines in which the use of mined water, as a secondary source of uranium, of other minerals, or their energy or balneology use would be possible.

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Radon levels after restoration of the U-mine disposal site

Križman M. J., Rojc J., Jovanovič P.

Nukleonika

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2010

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Vol. 55, No. 4

523-527

EN

After cessation of the underground mining of uranium ore and production of uranium concentrate at Žirovski Vrh (Slovenia) in the period 1985–1990, two permanent surface disposal sites remained, namely, tailings pile and mine waste rock pile. Both disposal sites were of equal size of 4 hectares and were significant sources of radon. Their final restoration was designed in compliance with the condition of dose constraint for the public and authorized limits for radon exhalation from the remediated piles. In the late summer of 2008, a restoration of the mine waste pile was finished. Radon releases were reduced significantly by constructing an effective radon barrier of well compacted clayey material and a thick complex protective cover layer constructed over it. Radon exhalation rate from the mine waste area was lowered from primary level of 0.7 Bq/m2źs to natural levels (0.01 Bq/m2źs), and consequently, ambient radon levels also decreased on the site and nearby environment. The average radon contribution from the remaining U-mine sources was estimated on the basis of the environmental measurements of radon concentrations; they dropped from initial 7–9 Bq/m3 to approximately 3 Bq/m3. Further reduction of outdoor radon concentrations is expected after 2010, since the restoration of another disposal site will have been completed by the end of this year. Public exposure due to industrial radon after the first phase of restoration satisfactorily meets the dose constraint level of 0.3 mSv/y, since it decreased to less than 0.1 mSv/y.

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Radon events in the U-mine environment and related radiation exposure

Križman M. J., Rojc J., Peter J. E.

Nukleonika

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2010

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Vol. 55, No. 4

529-533

EN

The term �gradon event�h indicates here a sudden appearance of enhanced radon concentrations, observed like well expressed peaks in time series of radon concentrations. The peaks are superimposed on normal diurnal periodical curves. The characteristics of radon events are high peak values, a rather short duration and a low radon equilibrium factor. Since radon events appear only in the environment near significant radon emission sources, they were investigated in more detail in the case of the former .irovski Vrh uranium mine (Slovenia), using the existing network of continuous radon progeny measuring devices. Eight different types of radon events were identified in the vicinity of the U-mine disposal sites, lasting for some hours and with the range of their peak levels of equilibrium equivalent concentrations (EEC) of radon from a few Bq�Em.3 to over 200 Bq�Em.3. Exposures to radon events in units of Bq�Eh�Em.3 were estimated for adult individuals of the reference group. They resulted in relatively high effective doses of the range 1.5 �ĘSv per a single event, thus exceeding, e.g. the total effective dose for the public due to radioactive discharges from most nuclear facilities during the whole year.

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Bioaccumulation of 226Ra in the plants growing near uranium facilities

Tykva R., Podracká E.

Nukleonika

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2005

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Vol. 50,suppl.1

25-27

EN

Radiopollution of soils in the close neighbourhood of a uranium mine and a uranium mill was characterized using measurement of specific 226Ra activity by gamma spectrometry. It was found that it ranged from values lower than the admissible limit of 0.2 Bq.g 1 of soil (averaged over the first 15 cm below the ground surface) to values more than one hundred times higher. Bioaccumulation of 226Ra from the measured soils in plant species which were naturally growing on the analysed sites was analysed. The specific 226Ra activity of aboveground dry plant parts ranged within two orders of magnitude. Currently occurring and simply collected Mentha piperita was found to be useful for biomonitoring of soils.