6.5.2 Operation and Maintenance
- Up to 508 return trips from vessels may be made per annum throughout the operation and maintenance phase, with up to 31 vessels on site at one time. These numbers are broken down in terms of vessel type in Table 6.4.
Table 6.4: Vessel Numbers During Operation and Maintenance Phase per Vessel Type per Annum
Vessel Type | Maximum Number of Vessels | Maximum Number of Return Trips |
|---|---|---|
Crew Transfer Vessel (CTV) / Service Operation Vessel (SOV) / Workboats | 9 | 117 |
Tug (Anchor Handlers) vessels | 6 | 200 |
Jack-up Vessels | 2 | 5 |
Cable repair vessels (including burial solution) | 2 | 40 |
Construction Support Vessels | 5 | 60 |
Dive Support Vessel (DSV) | 1 | 26 |
Other vessels | 6 | 60 |
Total | 31 | 508 |
- Up to 216 return trips from helicopters may be made throughout the operation and maintenance phase, with up to three helicopters on site at one time.
6.5.3 Decommissioning
- The decommissioning sequence will generally be the reverse of the construction sequence and involve similar types and numbers of vessels (albeit likely in lower numbers).