Organization

A key element in achieving effective decommissioning is having a relevant organizational approach at each stage, in the context of the utility and country concerned. Section 5.2.1.

discusses the range of organizational approaches being applied today by WWER operators preparing for decommissioning. Further generic guidance is provided in an IAEA report under preparation¹ and it is not intended to repeat that here.

5.2.1. Organization during preparation for decommissioning

The organization in the period well in advance of final shutdown does not necessarily need to be large. Assistance will be needed from those with detailed knowledge of the plant, technical experts and planning system specialists. It will also be vital for this team to learn from experience elsewhere so as to be able to consider the full range of options.

The number of people employed in decommissioning preparations by WWER operators ranges up to about 10 people. In each case there is a team leader for decommissioning but additional support is provided by plant personnel either as an extension of their normal duties or by temporary secondment. Such a structure corresponds with generic advice in the literature. Typically the work undertaken covers selection of decommissioning strategy, preparation of decommissioning documents, implementation of legislative requirements, data collection for decommissioning, as well as planning and management of research and development activities and other decommissioning topics.

WWER operators’ decommissioning organizations evolve as work progresses, and the demands change. Furthermore, the organization of multi-unit sites, where operation and decommissioning of units may happen in parallel, is addressed by the operators as well as for units in isolation.

5.2.2. Organization during project execution

The aim of decommissioning is to take the plant from a complex operating state to a much simpler state thereby reducing the hazard and the costs associated with maintaining the remaining systems and site. During operation there is a recurrent cycle, one or two years in period, where similar sequences of events occur through the years. On a decommissioning plant, although there are still repetitive activities, there is a net change taking place that requires an appropriate project organization. A project manager is essential. The organization at the commencement of decommissioning will inevitably be that which ended the operational phase of the plant’s life. The project manager needs to define and evolve the organization to suit the job. Part of the overall planning is to define how the organization, staffing, contractor usage, usage of mobile teams, etc. will be modified and controlled throughout the project.

The organization at a particular decommissioning project will be dependent on local constraints, whilst meeting the overall need for separation of project and operational

1 INTERNATIONAL ATOMIC ENERGY AGENCY, Organization and Management for the Decommissioning of Large Nuclear Facilities (in press).

responsibilities. For example, at Greifswald the structure is based on the pre-existing operations structure but with modifications to recognise new roles in project management and dismantling, and extended roles in areas such as work planning. The structure at Greifswald is given in Fig. 2. The project manager’s department (about 140 persons) plans, specifies and controls the dismantling work to be performed by the Plant Manager’s staff. The latter’s staff currently numbers about 600 plus up to 400 in the new dismantling department. As work progresses the numbers involved on plant operations, maintenance and engineering will fall whilst those in the project management area will remain the same for longer.

For other WWER operators there are no detailed organizations drafted as yet. However, an essential part of costing is to estimate the person-days to be employed and this is done in the context of an organizational model. A cost model for Bulgaria [13] includes a conceptual organization recognising the separation of project and operation derived costs.

5.2.3. Organization during safe enclosure

The safe enclosure phase is characterized by a plant of relative engineering simplicity which may require some operation, inspection, maintenance and monitoring but where the hazards are well defined and controlled.

As the safe enclosure phase is one of stability, there should be no need for any project staff. It is presumed that sufficient work has been performed to allow relaxation of the need for emergency arrangements. The necessary security measures may be able to be reduced and off site environmental monitoring may also be able to be scaled down.

The project phase is implemented to yield a cost optimized safe enclosure phase. The safe enclosure phase may last many decades so that any overmanning could lead to large overall costs. The policies of the country and the operator with respect to the discounting of future costs will have a major impact on what project work is judged economic to perform in order to lower surveillance and maintenance costs.

The size of the safe enclosure phase organization will depend on the level of dismantling and treatment of wastes that has been undertaken. It may even be appropriate to utilise multi-site mobile teams to perform much of the remaining work. A proposed structure is outlined in Fig. 3 and a significant degree of multi-skilling may be achievable in this organization.

Note the role identified related to record maintenance, vital to the successful deferred dismantling (see also Section 5.3.4).

5.2.4. Site clearance and completion organization

The final release of the site will require a simple organization focused on meeting regulator requirements to confirm, by measurement and evaluation as necessary, that the site is fit for controlled or uncontrolled re-use. This will be dependent on arrangements in a country and some guidance on this is provided in the appendices.

FIG. 2. Organizational structure during Greifswald decommissioning project.

Operations Health Physics Inspection and Maintenance

Record Maintenance Plant Supervisor

Fig. 3. Proposed organizational structure during a safe enclosure period.