RADON EXHALATION OF THE URANIUM TAILINGS DUMP DIGMAI, TAJIKISTAN
M. Schläger, Kh. Murtazaev, B. Rakhmatuloev, P. Zoriy, B. Heuel-Fabianek
Received: 29 FEB 2016,
Received revised: 20 APR 2016,
Accepted: 26 APR 2016,
Published online: 26 DEC 2016
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In a joint project of Forschungszentrum Jülich and the Khujand State University, a radioecological survey of the Digmai uranium tailings dump was carried out in the period from 2012 to 2014. In order to investigate the seasonal variation of the radon emission, automatic long-term measurements of the radon exhalation rate were performed at one location using a new device developed at Forschungszentrum Jülich. Area-wide measurements in 90 places showed the local variation of the exhalation rate all over the dump surface. In addition to exhalation meas¬ure¬ments carried out on the horizontal tailings surface, measurements were also per¬formed on the vertical walls of desiccation cracks where the radon exhalation rate was found to be significantly higher. The total annual radon emission of the tailings dump can be estimated at approximately 250 TBq. Beside the radon measurements, area-wide dose rate measure¬ments were carried out on the surface of the tailings and in tailings samples the Ra-226 activity concentration was measured by means of gamma-ray spectrometry.
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