Transcript SIXTH GENERAL RADIOACTIVE WASTE PLAN (6th GRWP)

ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
2008 ISOE EUROPEAN SYMPOSIUM
ALARA in the Dismantling of Nuclear Facilities
Alejandro Rodríguez (ENRESA)
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In 1984, the Spanish Parliament took the decision to create a public company to
undertake the management of the radioactive wastes generated in Spain and the
dismantling of nuclear power plants. As a result the Empresa Nacional de Residuos
Radiactivos, S.A. (ENRESA) was set up.
This is a public non profit-making company whose shareholders are the Centre
for Energy-related, Environmental and Technological Research (CIEMAT) and the State
Industrial Holding Company SEPI.
The main missions of ENRESA may be summarized as follows:
•
Removal, transport, treatment, storage and disposal and control of the
radioactive wastes generated in Spain.
•
Dismantling of disused nuclear and radioactive facilities.
•
Environmental restoration of uranium mines.
•
Research and development.
ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
“Closing the circle” Feedback in ALARA Process
PLANNING
• ALARA Forecasting
Feedback
• Contractor/Performer
OPERATING
EXPERIENCE
• RP&S Service
SUBSEQUENT REVIEW
PREPARATORY PHASE
•
Verification of Criteria
• Lessons learned
•
Preliminary data
• Comparison with Forecasts
•
Compilation of information
•
Specific training
•
ALARA Study
•
ALARA Group Meeting
CONTROL in PERFORMANCE
• Work Supervision
• ALARA Group Meeting
• Final ALARA Report
• Radiological Surveillance
• Dose evolution tracking
• ALARA Group Meetings
• Corrective actions
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
ENRESA ALARA ORGANISATION
ALARA COMMISSION (Management Level)
CHAIRMAN
enresa
TECHNICAL
DIVISION
OTHER
DIVISIONS
FUNCTIONS and RESPONSIBILITIES
ALARA
COMMISSION
Management Level
Director
El Cabril
Facility
Director
Vandellós NPP
Installation
Safety
Department
Decommissioning and Projects
Department
RP&S Serv. Manager
RP&S Serv. Manager
RPTU Manager
LMRW
Department
–
Promotion of ALARA culture
–
Approval and backing for Objectives
–
Provision of resources
–
Meets twice at year
–
Reports to MANAGEMENT Committee
Special Activities
Department
Implicit to the concept of ALARA is the need for strong support from the Management in its widest sense, as well as its direct participation in the
Programme implemented. The Management is responsible for ensuring compliance with the requirements of the competent authority, and in so doing
may delegate certain functions to its subordinates, acting via the hierarchical framework.
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Spanish Decommissioning Experience
Decommissioning of Uranium Mines & Mills
•
Andújar uranium mill, since March 1995 in Surveillance Period, with a minimum duration of 10 years
•
Works period: from 1991 to 1995
•
Budget: 24 M€
•
M3 Restored: 361.000
Initial situation
Final situation
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Spanish Decommissioning Experience
Decommissioning of NPP´s: Vandellós-I Project
•
Works Period: from 1998 to 2003
•
Budget: 94.605.769 €
•
Materials Involved: 300.000 t
•
Radwastes: 2.000 t
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Spanish Decommissioning Experience
Decommissioning of Research Facilities
CIEMAT (Spanish Centre for Energy related, Environmental
and Technological Research)
*
Research Reactor
*
Pilot Reprocessing Plant
*
Conditioning and Storage Plant for Liquid Waste
*
Dismantling works start in 2006 and will be
completed by 2009
*
Budget: 22.145.702 €
*
Material Involved: 7.000 t
*
Radwastes: 460 t
REACTOR JEN-1
Research
IN-01
IN-03
Reactor
Liquid
IN-07
Radioactive
Waste Storage
Liquid
Radioactive
Waste
Conditioning
Plant
IR-16
PLANTA M-1
Reprocessing
IR-18
Plant
EDIF. 55
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Spanish Decommissioning Experience
General Data
•
Reactor Type: PWR
•
Westinghouse One Loop
•
Gross Electrical Power:160 MWe
•
Containment Type: Dry
•
Containment Construction: Reinforced Concrete with steel dome
•
Spent Fuel Pool: Inside Containment
•
Works Period Expected: from 2009 to 2015
•
Budget: 135 M€
•
Material Involved: 101.031 t.
•
Radwastes: 4031 t.
Decommissioning of NPP´s: Zorita Project
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
ALARA in Decommissioning
The application of the ALARA principle and the Radiation Protection in decommissioning do not imply any significant novelty with respect to the
way it is applied at other operating facilities. Although in practice several differences arise:
•
The organization should be adapted to the new objectives of the project .
•
The physical configuration of the facility is modified continuously:
•
-
Loss of structural confinements (loss of isolation)
-
Modification of the systems (Effluents, radiation surveillance, etc)
The radiological status of the facility is continuously modified, and the radiological risks too
-
Modification of the routes for personnel and materials
-
Variation of the control areas
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. Evolution of Radiological Controlled Areas
WHITE LEVEL
GREY LEVEL
GREEN LEVEL
100%
RADIOLOGICAL LEVEL
70%
18%
154
19%
200
6%
4%
29%
180
6%
2%
160
140
31%
120
10%
50%
99
55%
85
40%
100
82%
79%
66%
49%
54%
20%
80
60
48
40
8%
10%
0%
TOTAL RADIOLOGICAL ZONES
2%
12%
60%
30%
1%
3%
173
80%
RED LEVEL
20
13%
4%
5%
1998
1999
ZONES
90%
ORANGE LEVEL
2%
5%
5%
9%
16%
YELLOW LEVEL
3
2000
2001
2002
0
2003
TIME
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. ALARA Organization (1)
FUNCTIONS and RESPONSIBILITIES
V1-NPP ALARA ORGANISATION
Manager
Vandellós-1

Dose objective proposals (V1-NPP)

Periodically informed on:
 practices,
ALARA
ALARA
COMMITTEE
 ALARA studies, and
 Training Programmes,
Managers
ENG+PO+PERF
Other
Services
and Areas
RP&S
Service
Technical
Manager
ALARA
COORDINATOR
ALARA
AREA
ALARA
Technician

Analysis of results obtained

Corrective actions

Reporting to ALARA Commission

Coordination V1-NPP Organisation

Approval of indicators

Participation and attendance in Training

Meets (4 times/year)
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. ALARA Organization (2)
V1-NPP ALARA ORGANISATION
FUNCTIONS and RESPONSIBILITIES
RP&S
SERVICE
ALARA
GROUP
ALARA
COORDINATOR
ALARA
AREA
ALARA
TECHNICIAN
OTHER
SERVICES
and
AREAS

Set up through meeting,

Proposals for improvements to be implemented,

Reports to V1-NPP Management,

Coordination of activities,

Analysis of specific activities and

Planning of specific tasks,

Performance of the following:
 work tracking, and
CONTRACTOR
COMPANIES
 results analysis,

Proposals for necessary improvements.
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. Criteria
CRITERIA for identification of work subject to
specific ALARA Tracking
CONCEPT/CRITERION
VALUE
OBSERVATIONS
1.- Collective dose (mSvm)
10
Total Per RWP
2.- Maximum individual dose (mSv)
2
Total Per RWP
3.- Dose Rate (mSv/h)
1
In Area
4.- Removal superficial contamination
Work Zones
4.1.- Beta-Gamma (Bq/cm2)
200
Accessible
4.2.- Alpha (Bq/cm2)
20
Surfaces
5.- Air-borne contamination (LDCA)
10
6.- Zone Classification
7.- Duration of work (H-p)
Red Zone
1.200
Total Per RWP/WAR limited occupation zone
8.- On request by RP&S Service
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. Results
ALARA Meetings during the project
Year
ALARA COMMITEE
1998
1999
2000
2001
2002
2003
Total
N/A
4
4
5
4
2
19
3
12
22
32
16
8
93
ALARA GROUP
ALARA Meetings during the project
•
30 Studies have been performed
ALARA Dose
•
Total collective dose of the project
552,95 m. mSv
•
Total collective dose of the dismantling activities
354,67 m. mSv
•
Collective dose regulated under ALARA studies
261,67 m. mSv
The 74% of the dose of dismantling operations has been controlled under the ALARA studies
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. Results
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. Cumulated Collective Dose
700
603,391
600
TOTAL PLANNED DOSE PDC
552,152
TOTAL PDC (CONTRACTORS)
TOTAL DOSE-DLD (CONTRACTORS+STAFF)
500
TOTAL DOSE-DLD (STAFF)
428,200
400
354,674
300
200
197,478
TIME
2008 ISOE
2003-T4
2003-T3
2003-T2
2003-T1
2002-T4
2002-T3
2002-T2
2002-T1
2001-T4
2001-T3
2001-T2
2001-T1
2000-T4
2000-T3
2000-T2
2000-T1
1999-T4
1999-T3
1999-T2
1999-T1
1998-T4
1998-T3
0
1998-T2
100
1998-T1
man.mSv
TOTAL DOSE-TLD
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
Vandellós I NPP Decommissioning Case. Lessons Learned
•
RP CONTROLS and STANDARDS
•
TRAINING and QUALIFICATION
•
STEPWISE CONFIGURATION AND DEPRESSURE SYSTEMS
•
VENTILATION
•
STAGES OF UNDRESSING
•
HERMETIC SEALING OF WORK AREAS
•
EQUIPMENT AND SYSTEMS FOR CONTINUOUS SURVEILLANCE
•
CONTROL BY BIOANALYSIS AND NASAL SMEARS
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ALARA IN THE DISMANTLING OF NUCLEAR FACILITIES
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