Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, 2006 Final Meeting of the contracts TW3-TSW-001 and -002 and TW4-TSW-001 and -002 ENEA part of the Art.5.1.a. task, and reminder of former results and reports L.Di Pace ENEA CR Frascati Garching, January 17 th, 2006

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Outline Status of decommissioning Decommissioning waste management Metal recycling market Radioactive scrap metal recycling & reuse Clearance & recycling standards and regulations Radioactivity measurement techniques and strategies Fusion industry implications Conclusions

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Status of decommissioning An entire generation of nuclear plants are ending the operating life; Hundreds of thousand of t/a will be produced by nuclear plants decommissioning within next 40 years; Only a limited volumetric fraction will contain the most of the activity. (99% of radioactivity concentrated in 1% volume). (Spent fuel is excluded) Time distribution for generation of slightly radioactive solid material from USA power reactor decommissioning

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Decommissioning waste management 3 options are envisaged for the radioactive waste: a.Clearance, (unconditional, unrestricted release); b.Conditional clearance: recycle, reuse in specified application and subject to regulatory control; c.No release from regulatory control, (management as radwaste). Each option has economic impacts due to the associate pricing for handling and disposal. –(average disposal cost in Europe in existing shallow land repositories is ~3000 €/m 3 ) –disposing of slightly radioactive metal from decommissioning in USA could range from 3100 to US$ /m 3 (depending from the repository)

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Metal recycling market #1 Steel is gold World population growth, ~ 9B within 2050, will require resources (including financial capital) to be used efficiently and effectively; Wastefulness will not be tolerated. The three Rs of Waste Management (Reduce, Reuse & Recycle) will become the basis of a new world philosophy; Metal, plastic and glass are recycled today in large quantities; Increase in the consume of recycled metal (~900·10 6 t/a for steel in 2002). (70% of steel produced in USA in 2003 are from recycling); Recycling allows great energy savings (60-75% for steel, ~95% for aluminium); And we avail of it

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Metal recycling market #2 The usual way of recycling steel is by re-melting scraps in basic oxygen furnace (1) with pig iron from blast furnaces, or solely in electric arc furnaces (2). (1) (2)

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Radioactive scrap metal recycling #1 Issue already in the agenda in 80s –90s; OECD-NEA study (1996) on 25 decommissioning projects in 9 different countries showed the following shortcomings: –clearance approach on a “case-by-case” basis; –absence of consistent international release criteria or national clearance standards. Few thousands of tons of metals are generated from the dismantling of a power reactor (non-radioactive or recyclable fraction  50-70%); Recycling of metals by re-melting ( in electrical induction heating and electric arc furnaces ); Mixing with non-contaminated scrap metal up to ~ 20% wt; Concrete debris are mostly non-contaminated and will pose no health risks.

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Radioactive scrap metal recycling #2 Radioactive Scrap Metal melting allows: –A large reduction in the radioactivity of the final ingot due to dilution and nuclides separation (in the slag and in the off-gas system); –Activity homogenisation and volume reduction; –Stabilised product suitable for final disposal.

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, International studies [ OECD-NEA e ANL (USA) ] showed advantages of the option recycle/reuse over dispose/replace as far as: –Worker and public health (radiological risk much lower than conventional ones - fatalities and disabling injuries from workplace and road accidents) ; –Energy and valuable natural resources savings; –Reduced environmental impact. Radioactive scrap metal recycling #3

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Radioactive scrap metal recycling #4 From the public acceptability perspective both options have problems at the moment. A portal truck monitoring system commonly used by steel mills to intercept incoming scrap metal

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Clearance & Recycling standards and regulations #1 Council Directive 96/29/Euratom [ Basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiation, [OJ no. 159, , p ];OJ no. 159, , p DisposalDisposal, recycling and reuse of material containing radioactive substances is subject to prior authorization; Any practice involving radioactivity requires justification; If yes: reporting and prior authorization or exemption if linked radiological risks are sufficiently low; Clearance is the removal of radioactive materials or radioactive objects within authorized practices from any further regulatory control by the regulatory body, The clearance levels are the recommended nuclide specific limits below which authorities could authorize clearance. They are based on radioprotection criteria.

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Clearance & Recycling standards and regulations #2

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Clearance & Recycling standards and regulations #3 Individual doses of some tens of µSv/a are considered trivial. To take into account multiple exposures: –Individual dose  <10 µSv/a per practice; –Collective dose  < 1 pers·Sv/a per practice. Radiological model to derive clearance limits of the single nuclide have to take into account all possible exposure scenarios: ingestion ( direct and indirect ), inhalation, and external  - radiation &  -skin-irradiation.

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Clearance & Recycling standards and regulations #3

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Clearance & Recycling standards and regulations #4 Documentation issued by international bodies ( IAEA, EC, NEA-OECD e US NRC ) related to “clearance” criteria and limits: –IAEA: TECDOC-855 [ TECDOC-855] and SAFETY GUIDE No. RS-G-1.7 [SAFETY GUIDE No. RS-G-1.7], TECDOC-855SAFETY GUIDE No. RS-G-1.7 –EC : RP89 [ RP 89 ] RP113, RP114, RP117, RP122 [RP 122] RP 89RP 122 –NEA-OECD [NEA-1996]NEA-1996 –US NRC : NUREG-1640 [ NUREG-1640 ] NUREG-1640 EC RP 134 [ RP134 ] – relative to the evaluation of the application of the concepts of exemption and clearance for practices according to title III of Council Directive 96/29/Euratom. RP134

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Table from EC RP 134: Need for harmonisation of Cls Case of tritium: from 0.4 Bq/g in UK up to 1.0E+6 Bq/g in the Netherlands Clearance & Recycling standards and regulations #5

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Radioactivity measurement techniques and strategies #1 Aim: ascertain the absence of radioactivity and/or the compliance with proposed limits; Direct measurement on material or on representative samples, or by other means retained sufficient by the competent national authority; The objective of keeping individual dose <10 µSv/a entails that dose rates to be measured are a small portion of natural background; need to operate at the lower boundaries of instruments detection; For nuclides difficult to measure it could be possible to link them to other nuclides.

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Radioactivity measurement techniques and strategies #2 Specify the mass or surface on which average the measurement ( distribution not homogenous ); Surfaces of few dm 2 and mass of few hundreds of kg (max. 1 m 2 and 1 t) may be considered as appropriate for averaging the measurement; Minimum No. of measurements defined by the regulatory authority ( i.e.: wall surface radioactivity ); When measuring the surface activity, it should be considered the “total activity” (removable + fixed surface activity) as well as that penetrated into the material from the surface ( i.e.: due to corrosion ).

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Radioactivity measurement techniques and strategies #3 Chances to measure  rays from the bulk; Limitation of the surface activity involves that of the bulk, by simply measuring the  radiation on the surface; For low energy  -rays or for  - and  -emitters the opposite problem might occur; they can go undetected if they are located under rust, corrosion or surface coatings; Other problems are: the geometrical complexity, the influence of the natural background, the accessibility of the item including their surfaces, and the sensitivity of the instrument relative to the criteria to be met; At any rate the state of the art in measuring of radioactivity is sufficiently developed to cope with the challenge.

Associazione EURATOM ENEA sulla FUSIONE Final Meeting of the contracts TW5- TSW-001 and -002 Garching. January 17 th, Conclusions The experience of decommissioning of an entire generation of nuclear facilities will be exploited by future fusion industry, (i.e. for recycling, reuse or disposal). The real waste management problem in fusion will be relative to the in-vessel components (IVCs). The fusion industry would have the advantage of being able to use activated metal, as it would be employed in a controlled environment, (radiation fields will be monitored). It seems more important to demonstrate the feasibility of IVCs recycling from the technical point of view, rather than to perform an economic assessment with the present-day terms. It would be greatly more important to concentrate the future activities on: 1.the study of the fusion material and equipment cycle and; 2.on the regulatory framework, within which recycling of fusion material could be performed.