At this meeting, the RSK concluded its discussions on its recommendation on the "Management of ageing processes at nuclear power plants". The RSK statement of 10.01.2002, which generally deals with this topic, was revised and included in this recommendation (Chapter 1 of the recommendation) specified by technical requirements for the areas of mechanical components, electrical components, I&C components, structural components, operating supplies, integrated operation management systems, documentation, maintenance of personnel competence, state of the art with regard to the ageing of concepts and technology (Chapter 2 of the recommendation). The new recommendations resolved replace the former statement.

Regarding the "Requirements for the demonstration of the effective emergency core cooling during loss-of-coolant accidents involving the release of insulation material and other substances", the RSK adopted a statement prepared by the Committee on PLANT AND SYSTEMS ENGINEERING (AST) which represents the state of the art in science and technology under consideration of recent studies. This statement is an update of the RSK statement "Effectiveness of the emergency core cooling systems during loss-of-coolant accidents involving the release of insulation material" of the 320th meeting of the RSK on 16.09.1998.
 

The RSK discussed the draft of the guideline on the probabilistic safety analysis submitted by the m BMU, including the appendant method volumes and the data volume. In future, these regulations shall be the basis for the safety reviews of the nuclear power plants in accordance with Section 19 a of the Atomic Energy Act (AtG). The discussion of the RSK did not lead to any general safety concerns regarding the drafts submitted. The BMU received particular information with regard to amendments, supplements and reviews for its further proceeding.
Further, the RSK dealt with two other topics within the framework of the revision of the nuclear rules and regulations (summary report of the 368th RSK Meeting on 11.12.2003). It discussed the classification of the existing safety requirements of the nuclear rules and regulations according to the different safety levels and the further development of the requirements on accident management. The results on the two topics will be considered in the revision of the RSK guidelines.

The RSK discussed the nuclear-specific safety-related questions of a capacity increase of the uranium enrichment facility in Gronau applied for especially regarding the question to which extent the technical and organisational measures provided are in compliance with the state of the art in science and technology. On this issue, a draft of a statement was available which included the review results of the Committee on SUPPLY AND WASTE HANDLING (VE) and gave answers to the questions posed by the BMU. In its discussion, the RSK arrived at the result that with the capacity increase the requirements on the safety-related design and safe operation to be applied in accordance with the state of the art in science and technology are fulfilled; this conclusion of the der RSK provided that the recommendations made by the RSK in the statement (in German) will be implemented.

The RSK adopted another statement (in German) in which the RSK Committees on PRESSURE-RETAINING COMPONENTS AND MATERIALS (DKW) and REACTOR OPERATION (RB) analysed the causes for a fuel assembly drop at the Biblis Nuclear Power Plant, Unit B and checked the applicability to other nuclear power plants.

The RSK discussed and adopted the following statements:

Project SR 2318 of the BMU "Assessment of the informational value of ultra-sonic and eddy-current examinations of austenitic RPV cladding" (in German),
"Safety aspects of the use of high burn-up fuel elements under reactivity-initiated accident (RIA) conditions", and
Gases in a repository (in German).

The RSK discussed the further proceeding regarding its review and assessment of the drafts for the revision of the nuclear rules and regulations performed on behalf of the BMU (http://regelwerk.grs.de).

The RSK discussed and adopted a statement on safety-related aspects of conceptual questions on the final disposal of irradiated fuel elements using canisters emplaced in bore holes by means of a comparison with the concept of drift emplacement of thick-walled containers (in German). The RSK is of the opinion that the further development of repository concepts such that the waste characteristics, the host rock conditions and the requirements regarding the safety during handling, operation and the post-operational phase is taken into consideration is an essential contribution to the realisation of safe final disposal. In the judgement of the RSK, not enough attention has been paid to this work in the past years and considers it to be required to resume the discussion on the further development of repository concept under consideration of different host rock formations. For this purpose, its statement compiles the safety-related boundary conditions for concepts for the final disposal of canisters in bore holes in different host rocks and points out differences compared to final disposal in massive metallic containers in drifts.

In the course of the meeting, the RSK prepared its comments regarding Module 1 of the revision of the nuclear rules and regulations performed on behalf of the BMU (http://regelwerk.grs.de).

This meeting concentrated on the formation of opinion of the RSK on the topics/modules of the revision of the nuclear rules and regulations performed on behalf of the BMU (http://regelwerk.grs.de).
At the meeting, the RSK concluded its comments on Module 1. It discussed the interim results of a working group regarding requirements on the in-depth safety concept. The requirements on precautionary measures such that further event analyses will no longer be necessary were compiled. With regard to digital I&C, postulated breaks, man-technology-organisation and radiation protection, the RSK discussed the respective assessment criteria on which the modules are to be bases.

The draft of the statement of the Committee on PRESSURE-RETAINING COMPONENTS AND MATERIALS (DKW) - "'Use of thermoelements for measuring the temperature of pipe walls in nuclear power plants within the framework of the fatigue analysis' and consideration of the medium influence in fatigue analyses according to the KTA safety standards" (in German) - was adopted.

At the 383rd meeting on 02.06.2005, the RSK discussed safety-relevant questions related to the decommissioning and dismantling of the Stade nuclear power plant and adopted a respective statement (in German) prepared by its Committees on SUPPLY AND WASTE HANDLING (VE) and on REACTOR OPERATION (RB).
Another focal point of the meeting was the continuation of the discussions of the RSK on the topic areas/modules of the new nuclear rules and regulations planned by the BMU.

At the 384th meeting on 07.07.2005, the RSK discussed and adopted the statements prepared by its Committee on
PLANT- AND SYSTEMS-ENGINEERING (AST) - "Switch-off of the main coolant pumps during ATWS events at nuclear power plants with pressurised water reactor" (in German) which includes some new stipulations compared to the statement "ATWS events" (of the RSK of 03.05.2001, 340th meeting),
REACTOR OPERATION (RB) - "Eddy current indications at control elements - reportable events 02/2003 at the Brokdorf nuclear power plant, 02/2004 at the Neckarwestheim nuclear power plant, Unit 2, and 08/2004 at the Emsland nuclear power plant" (in German).

The RSK dealt with the requirements for safety analyses on loss-of-coolant accidents; a corresponding recommendation is being prepared. Within the framework of the amendment of the nuclear rules and regulations, the RSK prepared its comments on Module 3 "Events to be considered at pressurised and boiling water reactors".

At the 385th meeting on 20./21.07.2005, the RSK adopted the recommendation "Requirements for safety analyses on loss-of-coolant accidents".
It continued its discussion on text modules for the amendment of the nuclear rules and regulations and prepared its comments on the Module 4 (Requirements for the integrity of pressure-retaining components and the confinement), Module 5 (Part 1: Instrumentation & Control, Part 2: Requirements for electric power supply, ..., control room), Module 6 (Requirements for safety assessments) and Module 9 (Radiation protection requirements).

At this meeting, the RSK discussed first of all internal issues. This was followed by an in-depth discussion of further chapters of the RSK recommendation on ageing management at nuclear power plants, which is at issue. The discussions on this recommendation shall be concluded at the 374th meeting. Regarding the requirements on the verification of the effective emergency core cooling during loss-of-coolant accidents involving the release of insulation material, the RSK discussed the currently available results of its Committee on PLANT AND SYSTEMS ENGINEERING (AST). Also in this case, a conclusion of the discussions and adoption of a statement is expected in the near future.