SUMMARY ......................................................... 1
1. INTRODUCTION ................................................. 3
1.1. Background .............................................. 3
1.2. Objective ............................................... 5
1.3. Scope ................................................... 5
2. MATERIALS ARISING IN LARGE QUANTITIES DURING
DECOMMISSIONING .............................................. 6
2.1. Overview ................................................ 6
2.2. Range of decommissioning materials and wastes ........... 7
2.3. Typical materials arising in the decommissioning of
specific nuclear facilities ............................. 8
2.3.1. Refining and conversion .......................... 8
2.3.2. Enrichment ....................................... 9
2.3.3. Fuel fabrication ................................. 9
2.3.4. Nuclear power plants ............................ 10
2.3.5. Spent fuel reprocessing ......................... 13
2.3.6. Research, institutional and industrial
facilities ...................................... 14
3. STRATEGIES FOR THE DISPOSITION OF LARGE AMOUNTS
OF DECOMMISSIONING MATERIALS ................................ 15
3.1. General considerations ................................. 15
3.2. Potential approaches for the disposition of
decommissioning materials/waste ........................ 17
3.3. Unconditionally released materials for recycling or
reuse .................................................. 19
3.4. Unconditionally released materials for disposal ........ 20
3.5. Radioactive material for conditional recycling/reuse
within the non-nuclear industry ........................ 21
3.6. Radioactive material for conditional recycling/reuse
within the nuclear industry ............................ 22
3.7. LLW disposed of in a dedicated repository or storage
facility ............................................... 24
3.8. VLLW disposed of in an appropriate storage or
disposal facility ...................................... 26
4. FACTORS AND CONSTRAINTS INFLUENCING OPTIONS FOR THE
DISPOSITION OF MATERIALS IN DECOMMISSIONING ................. 29
4.1. Quantities of materials ................................ 30
4.2. Technical feasibility and availability of technology ... 31
4.2.1. Infrastructure .................................. 31
4.2.2. Transportation .................................. 32
4.2.3. Characteristics of radiological contamination ... 32
4.2.4. Dilution with radiologically clean materials .... 33
4.2.5. Melting ......................................... 34
4.2.6. Chemical toxicity of radioactive materials ...... 36
4.3. Cost and economics ..................................... 37
4.4. Radiological factors and the application of clearance
levels ................................................. 39
4.5. National policy, public acceptance and legal
liability .............................................. 40
4.5.1. National policy ................................. 40
4.5.2. Public acceptance ............................... 41
4.5.3. Legal liability ................................. 43
4.6. Final status of decommissioning activities ............. 44
4.6.1. Site end state .................................. 44
4.6.2. Disposal options: Availability and
limitations ..................................... 44
4.6.3. Storage options: Availability and limitations ... 44
4.7. Hazards and risks to people and the environment ........ 45
4.8. QA and documentation ................................... 46
4.9. Environmental and ethical issues ....................... 47
4.9.1. Sustainability .................................. 47
4.9.2. Global optimization: Full cycle impact .......... 48
4.10.Methodology for decision making for selecting
disposition options based on specific influencing
factors ................................................ 49
5. METHODOLOGIES TO EVALUATE AND CHARACTERIZE MATERIALS
AND WASTES FOR DISPOSITION .................................. 51
5.1. Facility/site characterization ......................... 53
5.1.1. Historical information .......................... 53
5.1.2. Calculation methods ............................. 54
5.1.3. Characterization of the survey plan ............. 55
5.1.4. In situ measurements ............................ 55
5.1.5. Sampling and analysis ........................... 57
5.1.6. Data evaluation and verification ................ 59
5.2. Material management strategy ........................... 59
5.3. Monitoring strategy .................................... 62
5.3.1. Scaling factors (vectors) ....................... 63
5.3.2. Conversion of regulatory criteria into
in-field or laboratory measurement .............. 65
5.3.3. Main factors affecting measurement
methodology ..................................... 65
5.3.3.1. Type of material and its
physicochemical composition ............ 66
5.3.3.2. Geometry of the material and
accessibility to remaining
contamination .......................... 66
5.3.3.3. Surface condition ...................... 66
5.3.3.4. Type of contamination .................. 67
5.3.3.5. Homogeneity versus inhomogeneity of
contamination .......................... 67
5.3.3.6. Averaging in monitoring procedures ..... 67
5.3.3.7. Background level of radiation .......... 68
5.3.3.8. Efficiency determination ............... 68
5.3.4. Measurement uncertainties and their
acceptability ................................... 69
5.3.5. Determination of the detection limit ............ 71
5.4. Review of typical monitoring methodologies ............. 71
5.4.1. Direct measurements ............................. 72
5.4.2. Indirect measurements ........................... 76
5.4.3. Factors influencing the quality of monitoring
methodologies ................................... 77
6. CONCLUSIONS ................................................. 79
REFERENCES ..................................................... 81
ANNEX I: NATIONAL AND PROJECT CASE STUDIES .................. 89
ANNEX II: LESSONS LEARNED ................................... 187
GLOSSARY ...................................................... 197
CONTRIBUTORS TO DRAFTING AND REVIEW ........................... 201
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