OMV New Zealand recently announced a Maari Joint Venture project to undertake a further refurbishment on the mooring system of the field's floating production station, the Raroa.

AMOG has played a key role in assisting OMV with the previous work undertaken on the Raroa and will continue to do so during this next phase.

Background

In September 2012, AMOG was contracted by OMV New Zealand Ltd (OMV) to provide inspection and integrity advice for assets in the Maari Field in Cook Strait, New Zealand. During the subsea inspection campaign in early 2013, a number of anomalies were found on the wire rope and connections in the mooring of the FPSO Raroa. The progression of these anomalies led to a failure of Leg Two June 2013, following which a Short Term Remediation (STR) of the mooring system was conducted in order to replace Leg Two to improve the integrity of the mooring system whilst the Mid-Term Repair (MTR) was being engineered.

Subsequent developments in the project required that the vessel be disconnected from its STP Buoy ahead of the original MTR schedule. This necessitated a revision to the MTR design and planning, with the offshore refurbishment operations taking place during October and November 2013.

AMOG was extensively involved in this inspection and remediation project. Our scope of work included the engineering activities associated with the original inspection, the engineering of the both the STR and MTR mooring system designs (including approval by ABS), and the offshore support to OMV of the mooring system MTR refurbishment activities on board the Skandi Hercules.

As a result of these projects, in late November 2013, right on schedule, the FPSO Raroa returned to its position at the Maari field.

Next Phase

As OMV moves to complete the refurbishment of the mooring of the FPSO Raroa, AMOG's focus has shifted accordingly. AMOG is using its extensive expertise in mooring design, mooring integrity management and offshore construction to assist OMV in returning the mooring back to the condition required for the hostile environment of the Cook Strait. Modifications to both the mooring design and components in the mooring have been specified by AMOG to minimise the risk of further interventions in the future. These will best place the mooring to meet the intended design life.

At this stage, the project involves remediation work on all eight mooring lines. Work is expected to be carried our between February and April 2016. The investment in the system upgrade, including engineering, equipment and construction, is estimated to be approximately NZ$60 million ($A56 million).

All of the work is to be carried out in accordance with New Zealand regulations and international certification bodies.