Decommissioning and Dismantling of Commercial Nuclear Power Plants - Characteristics of Engineering Processing and Constructional Implementation

Following the heavy earthquake in Fukushima in 2011, the Federal Republic of Germany implemented a plan for the final phase-out of nuclear energy generation. Due to this decision, the subject of the decommissioning and dismantling of a large number of nuclear power stations with the related and extensive technical and economic challenges needs to be swiftly addressed. The final shutdown of major nuclear power plants, i.e. the power plants whose main undertaking was the generation of electricity did not play a major technical or commercial role in to date in Germany. These plants which were shut down were either prototypes, in which the technical equipment had not led to the planed power rating, or were plants which due to technical obsolescence, economic inefficiency or requirements from the statutory authorities were in a condition which rendered a further operation unattractive. In any case, it can be noted that these were isolated cases, which, under the protective umbrella of the otherwise profitable industry for the production of nuclear energy, were used to collect experience and test strategies for the future. Now however, eight reactors are more or less pending simultaneously decommissioning and dismantling. By the year 2022, nine further reactors are to be taken off the grid. The decommissioning and dismantling of these seventeen units will then run near to parallel. In addition to this, the plants are large and have had long operation periods. This results in additional characteristics and requirements in relation to the radiological considerations. From a commercial point of view, the development of unified and coordinated decommissioning and dismantling procedure would therefore be advantageous. In a working collaboration, the business units HOCHTIEF Consult IKS and HOCHTIEF Energy Europe have accompanied, both in the planning and in the technical execution, almost all previous decommissioning projects in Germany and as well as some abroad. The experience gained, and in particular the major differences when compared to dismantling of standard industrial plants, are reported on below.