SCOPE OF WORK
Pipeline Reconnaissance Survey
Lighthouse was entrusted by Customer to perform a pipeline reconnaissance with the scope to gather bathymetric, stratigraphic and seabed sediment information within a pre-defined corridor in order to establish the route feasibility. Two pipeline routes were proposed, the first one was the base scope of this survey and the second one was exercised as an option, depending on the feasibility of first route.
The Pipeline Reconnaissance Survey was performed according to the following steps:
- Pre-survey route centreline survey
- Post-survey route centreline and two wing lines 500m offset each side of centreline survey
- Pre-defined corridor survey
- Pipeline routes geotechnical characterization by means of box corer, piston corer and laboratory analysis
- Data processing, final charting and reporting
The project consisted in pipeline route 112km long survey and a pre-defined corridor 2220km2 wide survey by means of MBES, SBP and Mini Air Gun.
- The pre-survey route centreline was investigated by means of MBES and SBP in order to detect any possible hazard for the future pipeline lay. All the needed information was provided to Customer few hours after data acquisition in order to give him the possibility to modify the route. Once the post-survey route was defined, the survey was extended to cover a wider area. Then, the geophysical survey continued to complete the pre-defined corridor area.
- The last phase of the project consisted into the geotechnical survey with box corers and piston corers
Quality, Health, Safety and Environment
Personnel were following the guidelines of Company HSSE Management System, bridged with Customerâ€™s requirements by project-specific HSE Plan, Emergency Response Plan and a Risk Assessment, that identified potential project risks and ensured that the level of exposure is kept ALARP. No violations were recorded. In general, every attempt was made to comply with industryâ€™s best practice.
The offshore phase of the project lasted 1 month and a half, from December 2015 to January 2016 for the geophysical survey and March 2016 for the geotechnical one. This included the Survey preparation and mobilisation of the vessels.
The onshore final data charting and reporting, which included geotechnical samples analysis results lasted from January to May 2016 for the geophysical results (from Field to Final issues) and from March to August 2016 for the geotechnical results.
The Geophysical phase of this Pipeline Reconnaissance Survey was performed on board R/V Odin Finder, a 50 m long research vessel, owned by Lighthouse since 2001.
Equipment on board R/V Odin Finder
- Primary Positioning system: DGPS C-Nav 3050
- Secondary Positioning system: DGPS C-Nav 1010R
- Underwater Positioning: Sonardyne Ranger 2 6G
- Transponders (Beacon): Sonardyne WSM 8170 6G
- Gyrocompass/Motion Reference Unit: GEM Polaris FOG-200
- Gyrocompass/ Motion Reference Unit: Teledyne TSS MAHRS
- SVP Probes: Valeport Mini SVP â€“ Mini SVS
- Navigation Software: QPS QINSy 8.0
- Bathymetric System: L3 ELAC Nautik Seabeam 3030
- Sub-bottom Profiler System: Teledyne Benthos Chirp III
- Mini air gun: Sercel 20cu.inch
- Seabed Sampling Systems: 1000cmq Box Corer Nioz P.A.M. (Passive Acoustic Monitoring) System: TLS MK2 P.A.M.