Uranium in mining waters of kaolin open pit in Zarow (Lower Silesia); methodology of determination and genetic remarks

In this paper, a method of determination of uranium 238 and 234 in mining w aters of Andrzej kaolin open pit in Zarow (Lower Silesia) is presented. The method is based on independent measurements of alpha and beta radiation in tensities by means of a liquid scintillation spectrometer alpha/beta. The i nitial volume of water sample was 3 dm(3), then it was diminished by chemic al preparation to 6 cm(3), and then 12 cm(3) of scintillator was added. The lower limit of detection (for the measurement time of 8 h) for both U-234 and U-238 amounted to 0.02 Bq/dm(3). For determination of the uranium conte nt in ferruginous sediments precipitating from mining waters of the above-m entioned open pit, gamma ray spectrometry was used. The obtained results ma y be viewed as a contribution to studies on anomalous uranium concentration within this kaolin deposit. The elevated uranium content, in comparison wi th its average concentration in the Earth crust, is characteristic for pare nt rocks of Andrzej kaolin deposit, which are granitoids of Strzegom-Sobotk a massif. In connection with it, the high uranium content can be observed n ot only in kaolin and weakly kaolinised granitoids from the deposit in ques tion, but also in mining waters genetically related with them. (C) 1999 Els evier Science Ltd. All rights reserved.