Study for Danish competence and innovation center reveals that it is hard to generalise about environmental concerns in relation to the decommissioning of offshore oil- and gas structures.
Offshore Center Danmark is the official national competence and innovation center for the Danish offshore industry. The Center commissioned Ramboll to carry out a study with the purpose of providing an overview of possible issues of environmental concern involved in future decommissioning projects in the Danish sector of the North Sea. The scope of the study included decommissioning of production facilities with particular focus on the waste typically generated during removal operations.
At present no decommissioning projects have been executed in the Danish sector. In turn, the study utilised data from the Norwegian sector of the North Sea, which were correlated towards the size of production at the Danish Dan field used as a test case. To assess possible environmental issues related to decommissioning, the following topics were reviewed:
- Hazardous waste generated during production
- Hazardous waste described in decommissioning programmes
- Usage of production chemicals
The study concluded that there are many environmental topics to be taken into account throughout the process of each decommissioning project, e.g. planning, shutdown of operations, cleaning and preparation offshore, waste handling onshore etc. It was found that environmental challenges may vary markedly between different installations. Therefore, the validity of generalising environmental concerns connected to decommissioning was deemed questionable.