Taoufik Naamoun

Hydrogeochemical and Radiometric Investigation of the Uranium Tailings Schneckenstein - Text
(Text.PhDThesis)

Autor:	Naamoun, Taoufik
Geburtsdatum:	1965-01-25
Geburtsort:	Monastir / Tunesien
Email Adresse:	naamoun@hotmail.com
Titel der Dissertation in Deutsch:	Hydrogeochemical and Radiometric Investigation of the Uranium Tailings Schneckenstein - Text
Betreuer:	Prof. Broder Merkel
Betreuer:	Prof. Werner Stolz
Betreuer:	Prof. Detlef Hebert
Gutachter:	Prof. Broder Merkel
Gutachter:	Prof. Werner Stolz
Gutachter:	Prof. Detlef Hebert
Gutachter:	Prof. Peter Udluft
Gutachter:
Sprache der Dissertation:	ENG
Fileformat der Dissertation:	application/pdf
Filegrösse (MB):	159.58
Tag der Antragstellung:	2002-07-05
Tag der mündlichen Prüfung:	2002-12-18
Schlüsselwörter in Deutsch:	Uranium Tailings
AbstractURL:	GeowissenschaftenNaamounTaoufik663273.html
DissURL:	GeowissenschaftenNaamounTaoufik663273.pdf
Abstract:	The main goal of this thesis is the evaluation of the environmental contamination risk from the tailings materials. In order to achieve this task, hydrogeological, mineralogical, geochemical, hydrochemical, and isotope studies were conducted at the uranium tailings Schneckenstein. Four cores were taken at the tailing sites by drilling to different depths. Two borings were located in each tailing respectively. Samples were collected at an interval of 1 m. From the study, the cover layers has a coefficient of permeability of approximately 10-5 m/s, whereas for the tailings material, it ranges between 10-8 and 10-7 m/s except the last two intervals of the fourth borehole. The dry density is very low, whereas the grain density exceed 2.7 g/cm³ in almost all the materials. The total porosity is very high exceeding 30 % in almost all tailings. In addition, the infiltration rate in the tailings is low with a mean value approximately 8.8 cm/a. Muscovite and quartz dominate the mineralogy of the tailing sediments. For the analysed elements, the non residual fraction is in association with the iron and manganese oxides. Hence, the decrease of the oxygen contents in the environment will increase their solubility. Assuming an equilibrium between most of the radionuclides in the uranium chain before the ore processing and assuming that radium has not left the system e.g. as solute in water, not more than about 70 % of the total uranium content was removed during the ore processing. Also, the presence of organic matter and sulphur in the tailings material are the major factors controlling the solubility of elements in the areas. The hydrochemical model PHREEQC shows high solubility of most of elements. It also shows the change in chemical conditions between the heap materials and the tailing sediments which is characterised by a decrease of the Eh values with depth. This indicates the change of the medium to post aerobic or anaerobic conditions.
MD5-Prüfsumme:	a085ffe547d40a8d26d37c7e19304a5c

huringischer Einheiten (Lausitz, Elbe-Zone, Schwarzburger Sattel) korrelieren. Ein Vergleich der neoproterozoisch-frühpaläozoischen Entwicklung der saxothuringischen Einheiten mit anderen Segmenten des Böhmischen Massivs und des cadomischen Orogengürtels zeigt z.T. auffallende Ähnlichkeiten (insbesondere mit dem Mancellian Terrane des Armorikanischen Massivs) aber auch signifikante Unterschiede auf, die in der Arbeit diskutiert werden.