Site Investigation Strategy
Check out our default site investigation strategy that might be applied throughout the typical offshore wind project life cycle.
Geowynd can support you to develop your own site investigation strategy specific to your project and ensure that each element is specified and delivered at the right compromise between quality, schedule and cost.
Any available data
Conduct a thorough search for any available data at the site using historical records, publicly available resources or the results of past survey and site investigation works.
Conduct an offshore geophysical survey to map seabed sediment type and habitats. Ground truth this using geotechnical data usually GRAB samples.
Baseline Geophysical Survey
Conduct a relatively low resolution offshore geophysical survey covering the entire planned development area to determine the geology of the site, map surface features, characterise soil stratigraphy and identify ground risks in general.
Baseline Geotechnical Investigation
Conduct a geotechnical site investigation representative of the entire planned development area to measure in-situ soil properties and to acquire samples for laboratory testing.
Site Specific Geophysical Survey
Conduct a detailed geophysical survey at high resolution covering the planned WTG locations and cable routes.
Site Specific Geotechnical Investigation
Conduct a detailed geotechnical site investigation at the target WTG locations and on the planned cable routes including sampling, CPT and VC as necessary.
UXO Inspection Campaign
Conduct a detailed UXO inspection by ROV of the discriminated potential UXO target list to positively identify the target as a UXO or to positively rule this out.
Explosive Ordnance Disposal Campaign
Conduct an EOD campaign to neutralise or remove the positively identified UXO where relevant to the planned installation.
Planned Monitoring Survey
Conduct geophysical survey as part of planned monitoring to regularly inspect your assets through operations and ensure these remain healthy.
Planned Maintenance Survey
Conduct geophysical survey as part of planned maintenance to de-risk the planned maintenance works and ensure this is completed safely. Use these state-of-the-assets results to decide on any further works required as part of an observation method.
Unplanned Surveys and Site Investigation
Conduct further geophysical survey and / or geotechnical site investigation to support unplanned works in the field and ensure this is completed safely.
Cloud Based Ground Model and Geo Database
A database comprising all the soils data relevant to the site including geophysical and geotechnical data. The ground model represents the best of the knowledge of the site with all datasets being used to appraise and reappraise others to create the best possible site characterisation in the context of the planned development. The ground model is used to identify constraints and risks to the planned development and to make key decisions about the project.
Geoscience Desktop Study
Necessary for any project development, the geoscience desk study summarises anything that is known about the site to identify headline geo-risks early on and inform the approach for the overall project. A UXO strategy may also be developed at this stage to identify a minimum threat item for the site.
The environmental impact assessment is a necessary pre-cursor to any project development in order to understand and mitigate the unfavourable effects of the project on the environment or indeed identify ways to enhance the environment through the project development.
Site Constraints Register
The site constraints register identifies clearly all of the constraints relevant to the future development of the project including environmental, technical, aerial etc. and of course geological. Several site constraints maps are developed to clearly illustrate the site constraints affecting the development.
A preliminary foundation design is performed to appraise the technical and financial aspects of the project development with respect to the proposed founding solution.
Geotechnical Interpretive Reporting
A robust geotechnical interpretive report including static and cyclic aspects of the soils is completed. The GIR demonstrates the within-site calibration model for each of the relevant soil units and outlines the basis for the turbine specific selection of all strength and stiffness parameters required for input to advanced constitutive soil modelling as part of detailed design.
Installation feasibility and analyses is completed which might include pile driving analyses, penetration analyses for suction installed caissons or determining the ultimate holding capacity of a drag embedment anchor to a mooring line. Installation often has a big impact on the overall foundation design.
UXO ALARP Certificates
Before any operation requiring contact with the seabed is carried out, UXO ALARP certificates must be provided to cover the proposed operations in the relevant area of the site.
Geoscience Deliverables Data
An inventory of all of the geo-data and associated reporting comprising the ground model is compiled in a meaningful way for input to the HOTO list to ensure that all of the site data available is transferred from the development team to the operations & maintenance team.
Dependent on Maintenance Works
– UXO ALARP Certificates
– Jack-Up Leg Penetration Analyses
– Unplanned Reporting
During the 25 to 30+ years operations intervention works are almost inevitable. Several deliverables may be required to support the intervention works and to ensure that these are completed safely.
Foundation Concept Feasibility
A foundation feasibility assessment is completed which explores various foundation solutions that might be available or likely to be at the right technology readiness level according to the project schedule and identifies relative risks and costs in the context of the project under development.
Consent for Development
A consent for the proposed development must be granted by the relevant authorities in order for the project development phase to continue.
Final Layout (not micro-sited)
A final layout is developed in order to satisfy the site constraints register and to maximise the energy yield (and hence revenue) for the project development. Spare turbine locations may be introduced to include some redundancy in the case that a planned turbine location is not buildable.
Front End Engineering Design Foundation
A FEED is completed to develop all aspects of the foundation design as accurately as possible and with cognisance of all of the work completed so far as part of the project development.
Detailed Foundation & Cable Design
A turbine specific foundation design is produced unique to each planned turbine location and optimised through integrated load analyses to consider the soil-structure-load system particular to the location. Detailed cable design is also undertaken to consider thermal effects and other factors.
The final layout including turbines and cables is locally varied or ‘micro-sited’ as necessary to avoid known hazards. Spare turbine locations and associated inter-array cables, included in the planning so far, are confirmed or rejected as part of the final layout for installation.
Foundation Installation + Others
Foundations, scour protection and cables installation works are undertaken at the site. All as-built records, in & out survey data and all installation records shall be specified in detail and delivered to the end client to inform the future management of the assets through operation and to inform end-of-life extension and decommissioning.
Hand Over and Take Over List
An inventory of all of the data and associated reporting comprising the installed assets is compiled in a meaningful way for input to the HOTO list to ensure that all of the project data available is transferred from the development team to the operations & maintenance team.
Planned Maintenance Works
Planned maintenance works including cable reburial, reinstatement of scour protection and turbine maintenance etc. are completed to ensure the continued performance of the operational assets.
Unplanned Maintenance Work
Unplanned maintenance works relating to unexpected issues which threaten the performance or survival of the operational assets are completed to ensure the continued performance of the operational assets.
End-of-life Extension or Decommissioning
Towards the end of the planned design life of the project development, decisions are made as to end-of-life extension and ultimately the decommissioning of the assets in light of all that is known from the beginning of the project life cycle.