1. Decommissioning Plan for Kozloduy Nuclear Power Plant Units 1 & 2 E
Decommissioning Plan for Kozloduy Nuclear Power Plant Units 1 & 2 E. Demireva, O. Yordanova (ENPRO CONSULT LTD )
International Nuclear Forum
BULGARIAN NUCLEAR ENERGY – NATIONAL, REGIONAL AND WORLD SAFETY
BULATOM, May 28-30, 2008, Varna, Bulgaria

2. Background for development of the Decommissioning Plan
Act on the Safe Use of Nuclear Energy, in force since , State Gazette No. 63/ , modifications and amendments in State Gazette No. 70/ ;
Regulation for the procedure for issuing licenses and permits for safe use of nuclear energy, prom. SG No 41/ ;
Regulation for the safety of the decommissioning of nuclear power plants, State Gazette No. 73/
May 28-30, 2008, Varna, Bulgaria
BULATOM

3. Scope of the Decommissioning Plan
The contents of the Decommissioning Plan for Units 1 and 2 of Kozloduy NPP, Plc is in compliance with:
The Requirements of Article 59 of the Regulation for the Procedure for Issuing Licenses and Permits for Safe use of Nuclear Energy;
The BNRA guidelines presented in the “Guidelines for the format and the contents of a Decommissioning Plan;
IAEA guidelines, presented and the “Standard format and contents of the safety related decommissioning documents“, SRS No 45.
The Decommissioning Plan contains 23 chapters.
May 28-30, 2008, Varna, Bulgaria
BULATOM

4. Chapter 1: Short Description of the Basic Elements of the Plan
This chapter contains details of the Kozloduy license holder and the facility and presents a brief description of the basic components of the Decommissioning Plan.
May 28-30, 2008, Varna, Bulgaria
BULATOM

5. Chapter 2: Description of Units 1&2, their site, the special-statute areas and the emergency planning areas
The description of the facility is based of the original design of the units.
The changes are described, as well as the current status of the systems by the moment of issuance of this document.
The description of the special statute areas and these of the emergency planning complies with the areas of the whole site and no changes in them are expected by the beginning of the decommissioning activities.
The applied graphics provide information for the site and the facilities.
May 28-30, 2008, Varna, Bulgaria
BULATOM

6. Chapter 3: Description of the circumstances and events related to decommissioning, which have occurred during the operation of Units 1 and 2; the reasons for decommissioning
This chapter presents a detailed description for all the recorded events, that had occurred during Units 1&2 operation, as well as the for these events consequences for the decommissioning activities.
Events resulting in the radioactive contamination of the civil structures are described.
After the completion of Projects for radiological investigation of Units 1&2, the respective additional information will be added to this chapter of the plan.
May 28-30, 2008, Varna, Bulgaria
BULATOM

7. Chapter 4: List of the standards applied to decommissioning planning
This chapter presents the regulatory frame of the decommissioning process for the units
May 28-30, 2008, Varna, Bulgaria
BULATOM

8. Chapter 5: Radiological criteria applied to decommissioning
The proposed radiological criteria are subject of endorsement by BNRA and they include:
Individual occupational annual effective dose;
The dose intake by the members of the general public;
Limit of gaseous and liquids discharges to the environment;
Free Release Limits;
Limits for solid RAW transportation at Kozloduy NPP site.
May 28-30, 2008, Varna, Bulgaria
BULATOM

9. Chapter 6: Justification for the selected decommissioning option
According to the Continuous Dismantling Strategy, the decommissioning of units 1 and 2 will be done in two stages:
The first stage ( ) – Preparation for Safe Enclosure of RB1, SE Operation and dismantling of equipment outside the Safe Enclosure Area;
The Second Stage ( ) – deferred dismantling inside the Safe Enclosure Area and release of the buildings for reuse for other purposes.
May 28-30, 2008, Varna, Bulgaria
BULATOM

10. Chapter 7: Time-schedule and description of the decommissioning activities
May 28-30, 2008, Varna, Bulgaria
BULATOM

11. Chapter 8: Assessment of the amount, types and locations of the radioactive and other hazardous materials accumulated in the facility, including description of the assessment methods
The available information on the operational RAW is presented (origin, storage facilities, characterization, quantities of RAW) for the burnable, hazardous and conventional waste.
After the completion of Projects for radiological investigation of Units 1&2, the respective additional information will be added to this chapter of the plan.
May 28-30, 2008, Varna, Bulgaria
BULATOM

12. Chapter 9: Classification of systems and facilities
Category I—systems that are important for nuclear safety and radiation protection;
Category II – systems that are important for the industrial safety;
Category III – systems that are not important, i.e. that can be isolated and/or dismantles.
The systems form the three groups (I, II and III) are classified by four additional criteria:
1. Modification is required;
2. Modification is not required;
3. An unnecessary system;
3a – to be isolated
3b – to be conserved
3c – to be dismantled
New equipment.
May 28-30, 2008, Varna, Bulgaria
BULATOM

13. Chapter 10: Description of the planned modification to the existing systems and the new systems to be needed for the decommissioning stage
This chapter treats the systems that are considered to need changes in the original designs as well as the new investment projects, related to the decommissioning of Kozloduy NPP units, for which exist signed contracts, tender procures pr developed technical specifications.
May 28-30, 2008, Varna, Bulgaria
BULATOM

14. Chapter 10: Description of the decontamination activities, analyzed options and justification of the selection options
Loops/systems:
The hard decontamination option with applying the Cerium regenerative process has been selected.
The decontamination of the six Primary Circuit loops (+the Pressurizer) and the hot portion of SVO-1 will be done by the use of a movable decontamination facility. The hard decontamination will not be done for the auxiliary systems of the Primary Circuit (cold portion of SVO-1, SVO-2 and SVO-4). In case a possibility for a more effective, economically reasonable and practically proven method for decontamination of loops/systems occurs, KNPP will analyze the expedience of the selected option.
May 28-30, 2008, Varna, Bulgaria
BULATOM

15. Chapter 10: Description of the decontamination activities, analyzed options and justification of the selection options
Dismantled equipment:
It is planned to be commissioned by Size reduction and decontamination workshop (SEDW) The decontamination of the dismantled equipment will be done in the respective SRDW areas, as follows:
Area for mechanical decontamination provided with:
A box for decontamination by the use of water jet;
A box for wet abrasive decontamination;
Area for chemical decontamination;
Room for chemical and ultrasonic decontamination;
Room for electro-chemical and ultrasonic decontamination;
Room for Cerium decontamination;
Room for preparation of the chemical solutions.
May 28-30, 2008, Varna, Bulgaria
BULATOM

16. Chapter 12: Description of the available and planned technologies and technical means for dismantling
The below following principles will be followed during the dismantling:
To begin with the clean auxiliary facilities (buildings) and then the process continues with the TH, AB-1 and RB;
The planning is by systems, the performance is by rooms/elevations;
Various off the shelf techniques are used;
The beginning is in the RB and AB-1 and it involves the serviced and continues with the semi-serviced and the non-serviced rooms;
The replacement of large size primary circuit equipment for storage by the use of the respective biological shielding to a “decay storage” facility or storage in the RB-1 without dismantling. KNPP will make the final decision after the completion of the relevant analyses.
Initial in-situ cutting of the equipment to as large as possible parts and the secondary cutting for a size reduction in the specially arranged areas/SRDW for the purpose to make them up to such a length that is compatible with the free release pallets.
May 28-30, 2008, Varna, Bulgaria
BULATOM

17. Chapter 13: Program for RAW management
A description of the sources, the types and the quantities of the radioactive waste is done, whilst a provisional evaluation and a description of the radioactive waste, which will be generated during the decommissioning activities is included.
The RAW streams from Units 1 and 2 are updated where the decommissioning activities and the planned activities for radioactive waste treatment are considered.
RAW management stages are presented.
Criteria for sorting of materials for the purposes of free release and/or for their treatment as radioactive waste are proposed.
The planned methods for RAW treatment, conditioning and storage, the available technologies and facilities are described. Alternatives for treatment and conditioning as well as the justification of the selected option are presented.
The criteria and the options for materials reuse and recycling of are presented, which are based on the good practices in other countries.
Expected discharges of radioactive substances into the environment are assessed .
May 28-30, 2008, Varna, Bulgaria
BULATOM

18. Chapter 14: Safety assessment program for the decommissioning period
The Program is developed in compliance with the current standards, criteria and the international experience for decommissioning of nuclear facilities. An organizational structure and a managerial system will be maintained by the performance of the Program, which ensures highly qualified, well trained and well motivated personnel for the implementation and control of the activities related to:
Safe decommissioning of Units 1 and 2;
Safe management of RAW;
Protection of the environment, the personnel and the population;
Reliability and availability of the equipment.
May 28-30, 2008, Varna, Bulgaria
BULATOM

19. Chapter 15: Radiation protection concept
The main objective of the Radiation Protection Concept is to be followed all the radiation protection principles, requirements and limits during the implementation of all the decommissioning activities. These are achieved by:
Definition of the radiation and dosimetric criteria that have to be applied during all stage of the Decommissioning Plan (Chapter 5 of the Decommissioning Plan);
Development of programs and procedures, that have to be applied during all stage of the Decommissioning Plan (Chapter 16 of the Decommissioning Plan);
Define the applicable optimized radiation protection ways and place them in their logical dependence.
The developed monitoring programs, instructions and rules achieve and allow for following the Radiation Protection Concept.
May 28-30, 2008, Varna, Bulgaria
BULATOM

20. Chapter 16: Programs for radiation monitoring of the nuclear facility site and the special statute areas
The radiation monitoring programs are an integral part of the entire documentation that rules the radiation protection during a nuclear facility decommissioning and follow the radiological criteria as accepted in Chapter 5 of the Decommissioning Plan.
The individual occupational dose intake program documents are additionally included into the radiation monitoring programs. It has been identified, which governing documents, programs, instructions and documents are effective and no changes are expected for them as well as these that must be developed or updated during different stages of the Decommissioning Process.
May 28-30, 2008, Varna, Bulgaria
BULATOM

21. Chapter 17: Description of the organization and responsibilities of the personnel engaged in decommissioning activities specifying the personnel necessary for each decommissioning stage, evidences for the qualification of the personnel, as well as the measures taken and measures planned for maintaining and improvement of the personnel qualification
The available information for the administrative organization, functions and responsibilities of the personnel who performs the activities is presented.
The evaluation of the necessary personnel and the required qualification is done for units 1-4, based on the availability of a large number of common infrastructural projects.
May 28-30, 2008, Varna, Bulgaria
BULATOM

22. Chapter 18: Quality Assurance Program for the decommissioning stage
The Quality Assurance Program (QAP) describes the organization of the Quality Assurance management of activities related to the KNPP Units 1 and 2 decommissioning.
The QAP for decommissioning is consistent with the requirements of ISO 9001, IAEA and the relevant Bulgarian regulations.
May 28-30, 2008, Varna, Bulgaria
BULATOM

23. Chapter 19: On-site emergency plan for the decommissioning stage
The On-site Emergency Plan of Kozloduy NPP, Plc is developed in compliance with the requirements of the Risk Categories I, II and III, which also include Units 5 and 6 and it is a general plan for Kozloduy NPP site, where Units 1 and 2 are located.
The change of Units 1 and 2 statutes does not impose a change in the On-site Emergency Plan of Kozloduy NPP, Plc.
May 28-30, 2008, Varna, Bulgaria
BULATOM

24. Chapter 20: Documents defining physical security measures and, if necessary, measures for the physical separation of the decommissioned facility from the facilities in operation
Units 1&2 are located at EP-1 site and these are an integral part of the protected area of Kozloduy NPP, Plc.
Projects 3a and 3b were implemented after the final shut-down of Units 1&2, and the nature of these projects is the physical separation of Units 1&2 from Units 3&4, hardware and software changes and adaptation of the existing access control systems as well as modification of the existing communicational systems. Thus an effective system for physical protection has been implemented allowing achieving a balance in the protection, minimum consequences from single components failures, prioritizing of the protection according to the significance of the potential consequences, assurance of the required controlled access of individuals and MDV.
A security lane is planned to be constructed in 2008, aiming for the physical separation of EP-1 (Units 1-4) from EP-1 (Units 5&6).
May 28-30, 2008, Varna, Bulgaria
BULATOM

25. Chapter 21: Assessments of the financial resources necessary for the decommissioning stage and indication of the financing sources
May 28-30, 2008, Varna, Bulgaria
BULATOM

26. Chapter 22: Description of the monitoring programs, methods and means of site investigation after completion of the decommissioning activities aiming at exemption from regulatory control under the SUNEA of the site and the facilities
The methods and the technical means for investigation during decommissioning of materials and buildings of KNPP units 1 and 2 are described.
Details from events resulted in considerable deviations from the radiological status and the respective corrective actions will be recorded during the decommissioning process.
A Final Radiological Inventory will be done at the end of Stage 2, aiming to release the site and the on-site remaining structures, systems and components from the regulatory control under the SUNEA.
May 28-30, 2008, Varna, Bulgaria
BULATOM

27. Chapter 23: Time-schedule for reporting intermediate and final results connected with decommissioning process to the BNRA
A quality procedure “Completion of measures, activities or stages of the Decommissioning Plan fro Units 1 and 2” is planned to be developed. The Procedure has to be prepared not later than The activities for which completion will be submitted reports to BNRA have been defined
May 28-30, 2008, Varna, Bulgaria
BULATOM