The RSK discussed its further proceeding regarding the draft modules of the update of the nuclear rules and regulations planned by the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) and the workshop series of the BMU on this issue. The RSK addressed, in particular, the implementation of the RSK comments available so far (K1) in the current draft of Module 1.

The recommendation on loss-of-coolant accident/dead volumes reactor cavity prepared by the RSK Committee on PLANT AND SYSTEMS ENGINEERING (AST) was discussed and adopted with amendments.

The position of the RSK on the resolution proposal of the 59th KTA meeting was defined.

The RSK and the BMU continued their discussion on the revision of the nuclear rules and regulations and the way of assessment of the rules and regulations by the RSK. The RSK working groups presented information about the state of consultations on the draft modules of the rules and regulations.
The RSK prepared the joint discussion with the Commission on Radiological Protection (SSK) on the BMU order to give a statement on the GRS report “Safety requirements on the disposal of high-level radioactive waste in deep geological formations”. For the preparation of a draft statement, a working group of the RSK Committee on FUEL SUPPLY AND WASTE MANAGEMENT was established which also consists of SSK representatives.

At this meeting, the prevailing topic of discussions was the further proceeding regarding the project on update of the nuclear rules and regulations of the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) after its follow-up (module Version B) on the basis of the workshop series. The RSK agreed on a proceeding with five working groups which primarily review different module topics by means of an assessment catalogue. Their results shall be compiled for the RSK. On the basis of the preparatory work of a working group, scope and contents of this assessment were discussed.

In addition to a series of internal topics, such as the preparation of the Quadripartite Meeting in October 2006 in Washington (“International Cooperation”), the RSK dealt with the course of discussions for two orders of the BMU.

One of the orders covered the application of stability hypotheses for the calculation of cylindrical pipes under internal pressure at nuclear power plants. It was to be clarified under which boundary conditions the equivalent stress and shear stress hypothesis are to be applied. The RSK Committee on PRESSURE-RETAINING COMPONENTS AND MATERIALS will start the consultations.

The other order covers the Synthesis Report issued by the Federal Office for Radiation Protection (BfS) “Conceptual and safety-related issues regarding the disposal of radioactive wastes – A comparison of different host rocks” (in German). It is to be assessed, in particular, whether the questions and circumstances relevant according to the state of the art have been taken into account when dealing with the issues raised in the BfS synthesis report adequately. The RSK Committee on FUEL SUPPLY AND WASTE MANAGEMENT will start the consultations.

In light of recent events at the Swedish plant Forsmark 1, RSK had a first discussion. RSK prepared issues on the basis of a GRS report and data and information provided by the BMU which were to be dealt with by the RSK Committee on ELECTRIC INSTALLATIONS with the aim to analyse all disturbing factors and their impacts on the auxiliary or emergency power systems that go beyond issues related to the circuit design.

The RSK discussed and approved the statement “Description of the state of knowledge about the influence of gamma radiation on toughness reduction of ferritic materials of reactor pressure vessels during operation” (in German) prepared by the RSK Committee on PRESSURE-RETAINING COMPONENTS AND MATERIALS and the recommendation “Impact of advanced core loading on the reactivity behaviour of the reactor core and its reactivity control elements” (in German) prepared by a working group of the RSK Committee on REACTOR OPERATION.

The RSK discussed and approved the statement on the "Synthesis Report issued by the Federal Office for Radiation Protection (BfS) ‘Conceptual and safety-related issues regarding the disposal of radioactive wastes – A comparison of different host rocks" (in German) prepared by the RSK Committee on FUEL SUPPLY AND WASTE MANAGEMENT.

The RSK continued the discussions on the event at Forsmark 1. In the total course of events, different aspects were identified for which it was necessary to perform an in-depth analysis with regard to the applicability to German plants. In particular, questions concerning the generic applicability from the event sequences and, if appropriate, on the derivation of potential improvements were to be dealt with and an analysis of transient processes was to be performed in order to identify potentially existing deficiencies. The RSK recommends to also consider past experiences with events due to voltage transients and potentially modification measures in the studies at the German nuclear power plants performed on behalf of the BMU. The RSK Committee on ELECTRIC INSTALLATIONS continues the consultations.

The RSK discussed and passed its vote on the resolution documents on KTA standards to be dealt at the 60th meeting of the Nuclear Safety Standards Commission (KTA).

For the statement on the draft of new revised nuclear rules and regulations, requested by the BMU, the RSK completed its review criteria to be applied by the working groups established in their assessment of the different draft modules (392nd RSK meeting).

Following the previous discussions on analysis and conclusions from the event at the Swedish Forsmark 1 plant, report was given on the draft of a GRS Information Notice which had been dealt with more detailed by the RSK Committee on ELECTRIC INSTALLATIONS.

The RSK discussed and adopted following statements:
Control of loss-of-coolants accidents at PWRs under consideration of dead volumes in the containment - safety management aspects (in German),
Current approach for non-destructive tests performed within the framework of recurrent tests on ferritic-austenitic dissimilar welds (in German), and
Proposal for requirements on decommissioning in the nuclear rules and regulations (in German).

Further, the RSK continued its discussions in connection with the project on update of the nuclear rules and regulations of the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) and, for this purpose, discussed the Modules 2, 7, 8, 10, 11 as well as terms and definitions.

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 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".