Luis Yagüe Deputy General Director Asociación Nuclear Ascó Vandellós Colonia, 30/05/06

1. Action Plan to improve systems and organizational performance as a result of the Essential Service Water System Incident in Vandellós II NPP. Luis Yagüe Deputy General Director Asociación Nuclear Ascó Vandellós Colonia, 30/05/06

2. Garoña Vandellós II Ascó I & II Trillo I J. Cabrera Almaraz I & II Cofrentes Vandellós II site

3. Vandellós II site

4. Vandellós II performance data • Vandellós II Year Comercial Operation 1988 • Reactor Type W PWR 1087 Mwe • GROSS ELECTRICAL PRODUCTION (GWh)

5. Vandellós II performance data • CAPABILITY FACTOR

6. The Incident & the System

7. What happened?

8. What happened? On August 25, 2004 at 5:25 a.m. Vandellós II suffered a circumferential break on a manhole neck (EF-18-I) when starting-up pump EF P01 C

9. Impulsion train B D.G. B D.G. A Return train B Control Impulsion and Return train A Auxiliar Component Cooling B Cont. Spent fuel Turbine A C B The Incident & the System ESWS layout. Supports Component cooling, Essential Diesel Generators cooling, and Chilled water cooling. External piping: Buried BONNA pipe. Inside buildings: Carbon steel with epoxi liner >3”. SS or Monel <3”.

10. The Incident & the System Chest elevation, piping and man-hole of ESWS Lateral view, piping and man-hole of ESWS After identifying external corrosion in the presence of chlorides as the cause for rupture of the neck, all the remaining necks were inspected except the symmetric ones on the other train that had already been repaired. To a different extent all necks had degraded painting and corrosion. (In no case was the remaining neck wall thickness less than 2mm).

11. The Incident & the System Corroded zone Repair done in the two lower necks located downstream from the pumps on each train.

12. The Incident & the System Afterwards, and due to the presence of humidity on some necks, temporary repairs were performed on all of them. This was carried out by reinforcing such with bars welded to the neck flanges and reinforced concrete.

13. The Incident & the System The same corrosion mechanism was found on the transitions of buried to aerial piping in the entrance to the building or outside. During the refueling outage, external corrosion was seen on some zones of the internal carbon steel watertight piping close to the manhole facilities. This stretch of piping was completely replaced to the extent needed to bear material in good conditions. Afterwards, Extent of the cause was applied on all buried BONNA piping (on this system and also on the fire protection system). On other carbon steel piping outside buildings susceptible to corrosion due to seawater conditions inspections were performed such as many sample excavations, tests and studies. A hydraulic test was performed on all the BONNA systems.

14. The Incident & the System . Inmediate corrective actions • General:The cathodic protection, although it has not been 100% efficient, has minimized internal corrosion (maximum localized loss measured of 0.85 mm which is 10 times higher than the generalized corrosion). Therefore the main problem in Vandellós II is external corrosion despite it can be caused in some cases by welding defects. • Zone 1 Boxes: The most affected zone due to external seawater conditions. All this zone is replaced during the refueling. • Zone 2.1 Buried pipe except unions: Very small degradation observed. Good soil and concrete protection. Calculations show that pipe can support design loads with a complete loss equivalent to a hole of 60 cm in diameter of liner and rebar. • Zone 2.2 Buried pipe unions: As there are no reinforcing bars in this zone, such is the most critical part. Generalized corrosion of a maximum of 1mm and local corrosion between 2 to 3.5 mm has also been observed in this zone. Calculations show that these unions can support design loads with a generalized loss up to 1.5 mm remaining, and a local loss up to 2mm remaining in an area of 400 mm2. • Hydro tests: It was analyzed that a hole of 0.5 mm diameter in the unions would result in a leak of 17 l/h during a 6 bar pressure hydro test. The maximum values measured during test were 2.1 l/h. Main insights from the analysis performed by ANAV with the support of IET, CIEMAT, OXAND and IDOM:

15. The Incident & the System . Inmediate corrective actions • Main Conclusions: • After the repairs and hydro tests performed: there are sufficient safety margins to assure the structural integrity under all design transients. • Considering the different hypothesis and analysis performed: the current system can operate conservatively during a period of more than 5 years. • A hydro test will be performed every refueling until the replacement of the current system.

16. The Incident & the System . Main projects to upgrade the system • Addition of a new ESW safety class system that will add diversity with respect to the final heat sink (Forced circulation cooling towers) in two cycles. • Independent cooling systems for Diesel Generators and Chilled Water System through the addition of an air cooler specific for each system. • Replacement of all fire protection system - buried pipe also in the next two cycles. As future important physical actions identified in the Action Plan to improve Safety Management committed with CSN are:

17. Safety Management

18. Safety Management . Events analysis • Details on the sequence of events and on the root causes resulting from the internal root cause analysis performed by ANAV and the MORT (Management Oversight Risk Tree) analysis performed by an IAEA team with support from Conger&Elsea can be found in: • EAR PAR 05-039 posted June 29 2005 on the WANO web. • Thus the rest of the presentation will focus on ANAV Management insights and on the Action Plan to improve Safety Management accepted by the CSN (Spanish Regulatory Body). Note: In Spain the CSN is applying the SISC based on the NRC’s ROP (reactor Oversight Process). Thus regulator actions are in accordance with those taken at a U.S. plant with a red category in one cornerstone.

19. Safety Management . External independent evaluation • Group 1: Independent analysis of all aspects before and after the incident. Group 2: Nuclear Safety oversightmechanisms. Group 3: Evaluation of other recent events to evaluate common causes. Group 4: Safety culture evaluation. Group 5: Relationship between the Regulatory Body and the Plant Operator. As a part of the analysis, ANAV and CSN agreed to create the so called GAE (External Advisory Group) with 5 working groups:

20. Safety Management . ANAV Management diagnosis Main contributors identified by ANAV : • Deficiencies in some Safety culture attributesand conservative decision making focused on operation. • Responsibilities were not fully defined and understood in some cases and sometimes there is a lack of accountability (the “others” have the problem)”. This along with some lack of ownership is perceived as an indicator of leadership deficiencies. • Long and medium term planning,including resource allocation , needing improvements as well as clear and practical prioritization guidelines. • Lack or not use of the internal operating experience learning mechanisms. • Insufficient presence of the management in the field and deficiencies in the supervision both by the line and by the quality organization as well as the oversight mechanisms. • Vertical and horizontal internal Communication deficiencies as well as externally with the CSN. This deficiency is considered to have caused a deterioration in the relationship between both organizations.

21. Safety Management . Action Plan • As a result of all previous work done, the recommendations from these groups and a WANO Corporate Review, a final • Action Plan to improve Safety Management • was agreed and committed with the CSN. • This plan is currently in revision 3.

22. Action Plan to Improve Safety Management • Main Purposes: • - To improve safety culture and the safety conscious work environment. • Improve the system physical status and performance. • Regain confidence of CSN and main stakeholders. Schedule: - All actions implemented before the end of 2008 (6 month after 2008 refueling outage). Scope: - It considers 36 actions distributed in 5 Programs. Leaders create culture. It is their responsibility to change it”. Columbia Accident Investigation Board (CAIB) Report.

23. Action Plan to Improve Safety Management • EFR-01 Organization Mission, Vision and Values communication at all levels with entire support of Senior Management. • EFR-02 Management and leadership abilities development Plan, strengthening the self assessment and job performance evaluation. • EFR-03 Strengthening of Plan and Objectives development by all the organizational units. • EFR-04 Strengthening of the On Field Supervision Program. • EFR-34 Analysis of the results of the evaluation of other recent incidents in Vandellós II and definition of additional actions if needed. Management and Leadership Program (5)

24. Leadership for safety is clear Safety Culture Characteristics Action Plan to Improve Safety Management Management and Leadership

25. Accountability for safety is clear Safety Culture Characteristics Action Plan to Improve Safety Management • EFR-05 Revision of the “Reglamento de Funcionamiento” (Organization Manual that requires approval by Regulatory Body ) and the Organization Minimum Capacities Document . • EFR-06 Revision of Quality Assurance and Quality Committee functions. • EFR-07 Improvement of the performance of the Nuclear Safety Committees ( CSNC Plant and CSNE Corporate). Organization Program (3)

26. Safety is a clearly recognized value Safety Culture Characteristics Safety is integrated into all activities Action Plan to Improve Safety Management Management Systems Program (9) • EFR-08Work management improvement. • EFR-09Maintenance planning improvement. • EFR-10Change Management procedure reanalysis and implementation. • EFR-11Safety Culture Plan implementation. • EFR-12 Integrated Safety Management Manual development and implementation. • EFR-13Corrective Actions Program implementation. • EFR-14 Incidents analysis and evaluation process improvement. • EFR-15Design Change procedures revision. • EFR-16Operating Experience evaluation and use improvement.

27. Action Plan to Improve Safety Management EFR-17Use of communication as a tool for people integration and participation. Establish a Communication Strategy and a General Communication Plan with responsibilities, channels, frequencies and messages. EFR-18Interdepartmental Cooperation improvement. • EFR-19Improvement of the communication with CSN. Communication Program (3)

28. Action Plan to Improve Safety Management Communication Dr. John Carroll of MIT • Institutionalize surveys and dialogs with workers • Establish criteria for culture performance • The survey itself is almost irrelevant, it’s the conversations around the survey and the actions based on those conversations that are important

29. Action Plan to Improve Safety Management • The most important are: • EFR-23Revision of all Inspection Manuals • EFR-24Extended cause analysis to Ascó I and II systems. • EFR-27Life Management Plan definition and implementation through • Equipment Reliability Process. • EFR-29New diverse system for ESW in 2 cycles. • EFR-30Independent system for Essential Diesel Generators and Chillers • cooling. • EFR-31Fire protection buried piping replacement. • EFR-36Non Essential Service Water System buried pipe replacement Design, Inspection & Surveillance Improvements Program (16)

30. HT HT Train A LT LT EFTA EG EG EFTB Train B KJ - M 01 - A Action Plan to Improve Safety Management Design, Inspection & Surveillance Improvements Program (16) Diesel cooling System new ESWS Chilled Water System

31. Action Plan to Improve Safety Management Design, Inspection & Surveillance Improvements Program (16)

32. Action Plan to Improve Safety Management Design, Inspection & Surveillance Improvements Program (16)

33. Safety Culture Characteristics Safety is learning driven

34. Safety is a clearly recognized value Leadership for safety is clear Accountability for safety is clear Safety Culture Characteristics Safety is integrated into all activities Safety is learning driven

35. In the way to achieve the excelence

36. In the way to achieve the excelence • What fool you are. You vanished of learn from your own errors , when de best is to learn from the others. • Von Bismarck

37. In the way to achieve the excelence • Thanks • for your attention