Once all sources of energy have been isolated, the topsides can be prepared for removal. The ‘topsides’ refer to the facilities which sit on top of an installation, typically including drilling, processing and living quarters. Preparatory activities include the separation of process equipment from the wells and pipelines as well as module separation. Any activities to upgrade the facilities are also included in this part of the scope. This may include power upgrades to the installation to meet the decommissioning requirements. If a structure is to be left in place for any period of time, navigational aids may be installed during this phase.