The Environment Protection Authority (EPA) has received the visual inspection report of the Ocean Monarch mobile offshore drilling unit (MODU), indicating that the rig is unlikely to pose an immediate marine biosecurity risk in the River Derwent.
Diamond Offshore General Company engaged Tasmanian company Biofouling Solutions (BFS) to conduct a representative survey of the submerged surfaces of the Ocean Monarch using a Remotely Operated Vehicle (ROV) to determine the presence of any obvious invasive marine species, with particular focus on the colonial sea squirt, Didemnum perlucidum.
Mr Ford said that the visual survey of the MODU was undertaken on 5 January and according to the report, no obvious invasive marine pests were detected, although three small white-coloured growth-forms resembling the Didemnidae family were found.
“According to BFS, these colonies were not displaying any invasive characteristics and the presence of significant colonies in the inaccessible hull locations was considered unlikely," said Mr Ford.
“Based on the various areas inspected, the nature and extent of the biofouling, including the presence of three morphologically similar growth-forms to the Didemnidae family, the report concluded that Ocean Monarch is unlikely to pose an immediate biosecurity risk to the River's marine environment," said Mr Ford.
The visual inspection of the hull of the MODU was conducted in accordance with the direction given to the company by Mr Ford on 14 December. The company has advised the EPA that the MODU will be departing the Derwent in late January as originally planned.
A copy of the BFS report, ROV Inspection Summary (redacted) for the Ocean Monarch MODU is available here.