ROV Jobs in Decommissioning: What New Pilots Can Expect on These Projects

Decommissioning is one of the fastest-growing sectors for ROV work worldwide. As aging offshore platforms and subsea infrastructure reach end of life, ROV teams are essential for the complex, multi-phase process of safely removing or making safe these assets. Decommissioning work is diverse, technically demanding, and often involves working on structures that have been in the water for decades. This guide covers the major ROV roles in decommissioning projects.

Pre-Decommissioning Surveys

• General visual inspection (GVI) of the entire structure to assess current condition
• Close visual inspection (CVI) of critical lift points and structural nodes
• Marine growth profiling to determine cleaning requirements before rigging
• Debris surveys of the seabed around the structure
• Identification of any unexpected items (fishing gear, abandoned equipment, marine life)
• CP survey to establish the corrosion state before cutting operations

Platform Removal Support

During platform removal, ROVs provide real-time subsea observation and support for heavy lift operations. This includes monitoring cutting operations, observing rigging and sling positioning, confirming that structures are free to lift, and watching for dropped objects or unexpected movement. ROV pilots working on heavy lift operations must maintain excellent situational awareness and communicate clearly with the crane operator and project team. These are high-consequence operations where a missed observation can have serious safety implications.

Pipeline Flushing and Cleaning

• Confirm pipeline isolation before flushing operations begin
• Monitor discharge points for flow confirmation and contamination indicators
• Inspect pipeline ends after cutting for residual contents
• Document the condition of pipeline coatings and any damage observed
• Verify that all plugging and capping is completed to the required standard
• Record all flushing operations in the dive log with volumes and durations

Mattress and Protection Recovery

• Locate and survey all concrete mattresses, grout bags, and rock dump areas
• Assess the condition and recoverability of each protection item
• Rig mattresses for crane recovery using ROV-deployed lift lines or hooks
• Monitor mattress lifts subsea to confirm clean separation from the seabed
• Document any mattresses deemed unrecoverable with photographic evidence
• Record all recovery operations and remaining items in the decommissioning log

Post-Decommissioning Surveys

After removal operations are complete, regulators require post-decommissioning surveys to confirm that the seabed has been cleared to the agreed standard. ROVs conduct systematic grid surveys of the former site, documenting any remaining debris, seabed disturbance, and the condition of any items left in place by agreement. These surveys are typically compared against the pre-decommissioning baseline to demonstrate that the operator has met their obligations.

Documentation Requirements

Decommissioning projects generate extensive documentation requirements. Every inspection, cutting operation, recovery, and survey must be logged with video evidence, still photographs, and structured data. ThrusterLog provides a centralized platform for recording all decommissioning dive activities, making it straightforward to compile the comprehensive records that regulators and clients require for project close-out.