IAEA-TECDOC-447 RADIOACTIVE WASTE MANAGEMENT GLOSSARY. Second Edition

Transcription

1 IAEA-TECDOC-447 RADIOACTIVE WASTE MANAGEMENT GLOSSARY Second Edition A TECHNICAL DOCUMENT ISSUED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1988

2 RADIOACTIVE WASTE MANAGEMENT GLOSSARY, SECOND EDITION IAEA, VIENNA, 1988 IAEA-TECDOC-447 Printed

3 PLEASE BE AWARE THAT ALL OF THE MISSING PAGES IN THIS DOCUMENT WERE ORIGINALLY BLANK

4 The IAEA does not normally maintain stocks of reports in this series. However, microfiche copies of these reports can be obtained from

5 FOREWORD

6 ACKNOWLEDGEMENT The assistance of Dr. John A. Stone of the Savannah River Laboratory, Aiken, SC, USA in preparing and reviewing this report is gratefully acknowledged.

7 MAJOR SOURCES

8 RADIOACTIVE WASTE MANAGEMENT GLOSSARY absorption Incorporation within

9 activation product, neutron An element made radioactive by bombardment with neutrons. activity

10 alpha-bearing waste Waste containing

11 argillaceous Applied

12 basalt A dark-coloured Igneous rock, commonly extrusive, composed primarily of calcic plagioclase and pyroxene; the fine-grained equivalent of gabbro. Basalt is considered to be a possible host medium for high-level waste repositories. becquerel (Bq) The SI unit of radioactivity, equivalent to 1 disintegration per second (approx.

13 natural mineral waxes,

14 buffer zone A controlled area surrounding a nuclear installation (e.g. a waste repository) established to ensure an adequate distance between the installation and places used by or accessible to the public. burial ground An area of land that has been dedicated for the shallow disposal of low or medium level waste. Access by the public as well as future use of the land will probably be restricted. calcine To heat a substance to a temperature below its melting point, in air, to bring about

15 handling. Properties

16 environment from radioactive material produced during irradiation. For 11TR fuel particles, the multi-layer protective claddings are known as coatings. cladding waste Radioactive waste comprised

17 complexation A chemical term that refers to complex formation, in which a central metal ion is chemically bonded to atoms surrounding it. Depending on the circumstances, complexation

18 prevention

19 corrosion

20 waste forms based upon depletion

21 de minimis Part

22 devitrification The spontaneous change of a glass, in which the atoms display no long range order

23 domal

24

25 environment

26 far-field Rock formations outside

27 charges and allowing the neutralized particles to agglomerate and settle out.

28 geohydrology (or groundwater hydrology) A science that

29 granite Broadly applied,

30 The time necessary for a radioactive material in a living organism to be reduced to one-half of its initial value by a combination of biological elimination and radioactive decay is termed effective half-life. heat generating waste Waste which

31 human environment Those portions

32 ICRP limit A primary dose equivalent limit recommended by the ICRP. Dosimetric models may be used to derive the annual limit on intake (ALI) and derived I

33 interim storage (storage) Storage

34 leachability The susceptibility of a solid material to having its soluble, sorbed and/or suspendable constituents removed by the dissolving or erosive action

35 long-lived waste Waste that will not decay to an acceptable activity level in a period of time during which administrative controls

36 milling Operation

37 MPC

38 off-gas o

39 overpack Secondary

40 performance confirmation Tests carried out at a repository, usually after waste emplacement but prior to license termination, to confirm that the repository is performing as anticipated when emplacement of wastes was authorized. permeability

41 porous media Material that contains pores or cracks through which water or gas can flow. Often

42 Q quality assurance Planned

43 radioactive source term An expression used to denote information about the actual or potential release

44 radwaste See: radioactive waste. reactor waste Waste arising from

45 retrievability

46 safety analysis The analysis and calculation of the hazards (risks) associated with the implementation

47 scrubbing system

48 shallow-ground disposal (e.g. shallow-ground burial) Disposal

49 site

50 Sorption A broad term referring to reactions taking place within pores or on the surfaces of a solid. Its use avoids the problem of technical distinction between absorption

51 static leach test

52 tailings See: mill tailings. tailored ceramic A ceramic material whose composition

53 transuranic (TRU) waste Waste containing quantities

54 validation Validation

55 volume reduction

56 water table

57 validation Validation is a process carried out by comparison of model predictions with independent field observations and experimental measurements. A model cannot be considered validated until sufficient testing has been performed to ensure an acceptable level of predictive accuracy. (Note that the acceptable level of accuracy is judgmental

58 volume reduction A treatment that decreases the physical volume of a waste. Volume reduction is used to facilitate subsequent handling, storage, transportation or disposal of the waste. Typical treatments are mechanical compaction, incineration, or evaporation. Volume reduction results in a corresponding increase in radionuclide concentration. volume reduction factor (VRF) The ratio of the volumes of radioactive waste prior to and following treatment. In concentration processes the VRF is greater than one; in dilution systems,

59 water table (ii) (i) The upper surface of the groundwater;