Radiological protection for nuclear decommissioning in Italy · • Activation Products • Fission Products • Attinoids • Attinoids • Fission Products • Activation Products

Radiological protection for nuclear decommissioning in Italy

Fifth Workshop on Science and Values in Radiological Protection Decision Making

Milan, Italy – 19/09/2018

Roberto Falcone

Classes: Public Use, Internal Use, Controlled Use, Restricted Use Security Class: 2 Public Use

TABLE OF CONTENTS

SOGIN GROUP

RADIOLOGICAL PROTECTION

STAKEHOLDER INVOLVEMENT

RESEARCH AND INNOVATION

Classes: Public Use, Internal Use, Controlled Use, Restricted Use Security Class: 3 Public Use

SOGIN GROUP

Sogin is the Italian State owned company responsible for the decommissioning of Italian nuclear facilities and the management of radioactive waste.

Sogin is also in charge of the siting, design, building and operation of the National Repository.

Classes: Public Use, Internal Use, Controlled Use, Restricted Use Security Class: Roberto Falcone – Milan – 19/09/2018 4 Public Use

SOGIN SITES – RADIONUCLIDES INVENTORIES

Power Plants and

Research Reactors

Fuel reprocessing

Research Plants

Fuel production plants

(research and industrial)

• Activation Products

• Fission Products

• Attinoids

• Attinoids

• Fission Products

• Activation Products

• Attinoids

Trino, Caorso,

Latina, Garigliano

and Ispra

Saluggia, Casaccia

and Rotondella

Bosco Marengo and

Casaccia

SOURCE TERMS

imp

ort

ance


DECOMMISSIONING – RISK EVOLUTION

Lower exposure dose

rates

LOWER RISK No more fissions, neutrons and activation Primary circuit decontamination

Radioactive Decay Lower quantity handling

HIGHER RISK Fuel translation Primary circuit and pool decontamination Primary circuit and pool dismantling

Cells / Glovebox cleaning and dismantling

Higher risk of

contamination spread (internal exposure)

Risk for actinoides could become more important

• Some post shut-down operations lower some exposure sources

• The safety role of many engineered structures, systems and components (SSCs) during

decommissioning will differ significantly from their role, during the operational phase of a facility • Decommissioning involves the breach of containment and other engineered safety barriers

• New barriers, systems and plants have to be designed and built

Classes: Public Use, Internal Use, Controlled Use, Restricted Use Security Class:

SOGIN

ORGANIZATION

Safety Analysis & Assessment of

Operations and Processes

Radiation Protection approach

and optimization

Stakeholder Involvement

Techniques (Innovation)

Roberto Falcone – Milan – 19/09/2018 6 Public Use

INTERNAL ORGANIZATION FOR DECOMMISSIONING ACTIVITIES – CENTRAL AND ON SITE

Site Experts Engineering and Radiation Protection Dept. Research and Innovation

Dept.

Site Experts Engineering and Radiation

Protection Dept. Experts Licensig Dept.

Site Managers Licensig Dept. External Relations Dept.

DECOMMISSIONING

NEW REQUIREMENTS


ETHICS - RP OPTIMIZATION AND MANAGEMENT OF EVENTS

Communication to

Authority

Event recording and

analysis (done by

procedures)

By Events, Anomalies

and Near Miss

Corrective actions

Authority

considerations and

specifications

Report to Authority

ALL

ACTIVITIES

(By RP Feedback)

If optimization

possible


DOSE LIMITS, CONSTRAINTS AND ALARA APPROACH

DOSE LIMITS IN ITALY (Annual Effective Dose)

Public 1 mSv

Workers 20 mSv

Ethical approach of radiation protection suggests optimization and “ALARA”

methodolgy.

Limits and constraints are useful and effective for optimization and ALARA

implementation.


WORKERS DOSE CONSTRAINTS

Annual Individual Effective Dose

Value Comments

15 mSv Decommissioning Operations and

Safe Storage (existing sources)

3 mSv New sources for decommissioning

Individual constraints are considered as upper limits, reachable, E.G. if useful for collective dose

optimization.

DOSE CONSTRAINTS FOR NORMAL OPERATION - WORKERS

Annual Individual Committed Effective Dose

Value Comments

< 0,1 mSv

internal contamination should be avoided

In Decommissioning Operations, Safe Storage

and for New Sources,

0,5 mSv Admissible if justified by optimization

processes

Classes: Public Use, Internal Use, Controlled Use, Restricted Use Security Class: Roberto Falcone – Milan – 19/09/2018

10 Public Use

(*) Apply in normal operation and to events that are expected to happens (Event Category I)

PUBLIC DOSE CONSTRAINTS (*)

Annual Individual Committed Dose

Value Comments

< 0,01 mSv

Below this value, no more optimization is

needed.

Reference value for technical specification

and environment monitoring.

Reference level for “Clearance – Exemption”

DOSE CONSTRAINTS FOR NORMAL OPERATION – PUBLIC


11 Public Use

Risk constraint are given in term of dose related to the probability of a potential exposure.

RISK CONSTRAINTS FOR ANOMALIES AND ACCIDENTS

WORKERS RISK CONSTRAINTS

Workers Individual Effective Dose

Annual probability (Event Category)

Dose limit related to probability Comments

10-2 < P < 1

(II) 20 mSv 40 mSv is the limit in the Italian law, for

«exposures with special authorization»

applying in exceptional situations,

excepted radiological and nuclear

emergency. P <10-2

(III) 20 ÷ 40 mSv


12 Public Use

Risk constraint are given in term of dose related to the probability of a potential exposure.

VALUES – RISK CONSTRAINTS FOR ANOMALIES AND ACCIDENTS

(BDBA: Beyond Design Basis Accident)

PUBLIC RISK CONSTRAINTS

Individual Effective Dose

Annual probability (Event Category)

Dose limit related to probability Comments

10-2 < P < 1

(II) 0,001 ÷ 0,1 mSv Cumulated limit must be < 0,01mSv/year

10-4< P<10-2

(III) 0,1 ÷ 1 mSv

Over 1 mSv, dispositions for intervention

on nuclear emergency are applied

Special External Events

and BDBA

P < 10-4

1 ÷ 10 mSv


13 Public Use


• 3 fundamental drivers for Sogin’s relationship with stakeholders

• Stakeholder involvement strategies

1. Providing information and accessible tools (like websites, RE.MO. Project or Sustainability Report)

2. Keeping national and local stakeholders informed

3. Providing complete transparency on data and activities

4. Engaging each relevant stakeholder in a direct relationship

Information Transparency Involvement


14 Public Use

INFORMATION

• 3 WEBSITES

Sogin.it – corporate info

Nucleco.it – business oriented

Depositonazionale.it – dedicated to stakeholders

• MEDIA RELATIONS


• Invitation by Regional administration (host)

• Participation of multistakeholder panel (local institutions, environmental associations, Regulatory Authority)

• Sogin, as installations’ operator, illustrates the dismantling and securing activities related to the nuclear site and provides documents and analyses on a technical basis.

TRANSPARENCY ROUNDTABLES

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The report, published every year, is a tool that resumes all relevant information for stakeholders

It is aimed to:

• Collect and update any significant information inside the company

• inform every stakeholder about company’s core data and activities

• Illustrate economic, social and environmental performances

• Promote a more sustainable profile among the relevant stakeholders

• To be a part, as a public operator, of the sustainibility culture among the stakeholders

SUSTAINABILITY REPORT

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17 Public Use

ENVIRONMENTAL MONITORING

RE.MO. Project

• Sogin developed a cartographic portal named “RE.MO. – REte di MOnitoraggio” (Monitoring network) which collects data on conventional and radiological environmental monitoring of nuclear facilities, as well as information on the progress of decommissioning projects.

• It can be accessed on any device, and has one main graphic interface that give users access to information, with links that users can click if they want to know more.

• Each nuclear site contains four sections, regularly updated:

- Activity Status

- Conventional Environmental Monitoring

- Radiological Environmental Monitoring

- Monitoring of Functioning Sites


In 2015 and in 2017 Sogin opened simultaneously the nuclear sites for a weekend.

Both times it has been successful in terms of participation and satisfaction among visitors.

High lights 2017 edition

5 nuclear sites opened

3.000 visitors

100 journalists

450 press reports (on newspapers, TV and web)

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Open Gate


19 Public Use

RESEARCH & INNOVATION - Prototypes Most of the R&I activities are aimed to processes and produce prototypes. All these

have concerns with Radiation Protection and are aimed to dose and environment impact reducing.

Robotic Scarifier Tool for Dismantling of Contaminated

Stack at Garigliano NPP

Handling / removal Equipment

Latina graphite piles

Waste Management Casaccia GB Cem for Alpha Active Liquid Waste

(Patent Appl.)


20 Public Use

RESEARCH & INNOVATION – Contamination monitoring

Granulometry of contaminants gives information on their inhalability and on doses in case of

accidents

In radiation protection for decommissioning, contamination monitoring for workers, public and

environment, both in accident or in low dose exposure situations, is important.

Low level dose assessment needs high sensibility measures that often are influenced by natural or

artificial background (E.G.: natural uranium in food and water, plutonium by nuclear tests fall-out

or nuclear accidents or legacies)


21 Public Use

RESEARCH & INNOVATION – Uranium

AMS Characterization for 236U/23XU determination on some plants

Natural uranium in food and water creates an oscillating background

in escreta which will give strong interferences in case of uranium

inhalation or spreading, in case of enriched uranium too

Irradiated uranium has a high content of 236U, fairly

not present in natural matrices Accelerator Mass

Spectrometry is a sensitive analysis techniques able

to measure very low concentration of 236U


22 Public Use

RESEARCH & INNOVATION – Uranium

Garigliano NPP: 236U/23XU Map

• Characterization of ratio 236U/23XU of the plant can help to distinguish artificial from natural contribute to the activity.

• Characterization already done in Garigliano NPP.

• Now Sogin is working on Casaccia plant (for radiotoxicological applications).

(Collaboration with Campania University )


23 Public Use

RESEARCH & INNOVATION - Plutonium

Sampling and Analysis methodologies for combined

NT and SEM chacterization

Plutonium and MOX (Mixed OXide) powders have strong variability in granulometry, U/Pu activity ratio and chemical composition.

Nuclear Tracks (NT) methods can individuate and measure activity of single alpha emitting powder particles.

Scanning Electron Microscopy (SEM) can easily individuate high Z powder particles,

take pictures and analyse elemental composition.


24 Public Use

RESEARCH & INNOVATION

Nasal mucus sample

(accidents)

Alpha tracks on CR39 slab

CR39 slab on Samples of

contamination

Plutonium particles on a smear

X spectrum of the particle

(Collaboration with ENEA)

We protect the present

We guarantee the future

Documents

Radiological protection for nuclear decommissioning in Italy · • Activation Products • Fission Products • Attinoids • Attinoids • Fission Products • Activation Products