Legasea offer services to remove marine growth from subsea structures, following decommissioning or recovery of equipment for storage or refurbishment.

 

Following submersion subsea, structures are colonised by opportunistic marine organisms that adhere to the structure. These start to grow on platform legs and other subsea structures after they have been in the sea for only a few months, and the quantity is much larger after many years in the sea.

Mussels, barnacles, benthic algae and sea cucumbers quickly colonise installations, followed by soft corals and after some years colony-forming stony corals. The species that colonise a particular installation will depend on a number of factors such as water temperature, currents, water depth, distance from land, latitude and the season in which the structure was installed.

 

These are defined as marine growth, and these can consist of a range of different species on each single structure. Following recovery, and transport to shore, this marine growth must be managed.

 

In the UK, the Environmental Protection Act (1990) defines marine growth as a 'Controlled Waste', and this definition applies as soon as the structures arrive onshore. As a SEPA licenced Waste Management contractor, Legasea can offer cleaning services to remove the marine growth, ensuring that it is responsibly segregated and transferred to an authorised third party for disposal, prior to equipment being reused or placed in storage.