Plan, do, check and act
Once the optimal final scenario has been selected by the stakeholders, it needs to be implemented, monitored and reviewed. An implementation plan will need to be developed within the IMS to support the stakeholders in successfully executing the management scenario.
A monitoring programme will need to be developed to control the performance of the management scenario, to fill previously defined monitoring data gaps and define the main site investigation needs for certain scenarios. The information and data that are obtained in this way will be added to the central megasite database. After a certain period an update has to be made of the site description and the management scenarios. This might have consequences for the implementation of the management scenarios: priorities may change or additional measures may have to be taken. Also the timeframe for implementation may change. All these changes have to be discussed with the stakeholders (see figure below).
In the medium and long-term, a review of the IMS process needs to be made. Beside a review of the performance of the management scenario and the possible fall-back scenario, the following changes have to be taken into account:
- Changes in the boundary conditions (legislative framework, political and economic issues, changes in owners and responsible authorities)
- Changes in stakeholder objectives
- Unexpected changes in the megasite situation or conditions (climate change, large-scale groundwater obstruction, catastrophic events)
These changes can seriously affect the general objectives and efficiency of remedial actions, and taking them into account is very important for a successful implementation of the IMS. Contingency plans need to be made to deal with potential changes.
