Impact & Risk

A summary of the aspects of the project which interact with the environment, their potential impacts and risks, and proposed mitigation and management strategies, are outlined below.

To view the full assessment, go to the Offshore Project Proposal document here.

Project aspect

Planned impacts include:

• drilling of the foundation wells with a drilling rig;
• Crux platform, export pipeline and subsea infrastructure;
• presence of project vessels and vessel movements; and,
• seabed disturbance.

Unplanned risks include the collision of a project vessels with marine fauna.

Ensuring all project vessels operating within the project area adhere to the navigation safety requirements at an international and national level.

Maintaining a minimum 1km buffer from shoals within the in-field development area.

Directing project vessels to adhere with national requirements regarding interacting with cetaceans.

Undertaking seabed surveys prior to installation of infrastructure.

For more information visit Section 8.4.1, page 276

Planned impacts include light emissions from platform and vessel navigational, and operational lighting and flaring.

External lighting on offshore facilities/infrastructure will be minimised through design to that required for navigation, and safety of deck operations, except in the case of an emergency.

Flaring during operations will be optimised to enable the safe and economically efficient operation of the facility.

For more information visit Section 8.4.2, page 294

Planned impacts include underwater noise generated by:

• piling;
• vertical seismic profiling;
• ongoing operations; and,
• vessels.

Maintaining a minimum 1km buffer from shoals within the in-field development area.

Managing pile driving activities to ensure adherence to industry standards including:

• safety zones – observation and shutdown zones;
• standard management and mitigation procedures, e.g. pre-start, soft start, normal operation, stand-by and shut-down procedures; and,
• trained crew members as observers.

For more information visit Section 8.4.3, page 308

Atmospheric emissions*

Air emissions will be generated by a number of sources such as combustion engines, flaring, transportation emissions (vessels and helicopters) and fugitive emissions.

Planned impacts include:

• decline in local or regional air quality; and,
• contribution to the incremental build-up of greenhouse gases in the atmosphere.

Complying with international emissions standards requirements.

Completing and submitting annual National Greenhouse and Energy Reporting documents during the operations stage of the project.

Ensuring flaring during operations is optimised to enable the safe and economically efficient operation of the facility.

Ongoing assessment of greenhouse gas reduction opportunities during the life of the Crux project

For more information visit Section 8.4.4, page 328

Planned project activities could introduce or transport invasive marine species to the project area.

Possible methods of introduction include:

• biofouling;
• ballast water discharges; and
• via the flexible riser between the Crux platform and Prelude FLNG facility.

Complying with national and international requirements for ballast water exchange operations.

Ongoing biofouling management for vessels in accordance with guidelines.

Continuing compliance with national biosecurity legislation.

Maintaining a minimum 1 km buffer from shoals within the in-field development area.

For more information visit Section 8.4.5, page 333

A range of activities will result in the generation of waste materials, including recyclable, hazardous, and non-hazardous materials, which will be regularly transported to shore.

The planned management of these wastes will not result in any impacts to the marine environment.

Improper storage and handling may result in the accidental release of hazardous or non-hazardous solid waste to the marine environment.

Ensuring waste from vessels will comply with all relevant requirements. 

Implementing waste management procedures that include steps for waste segregation and storage, safe handling and transport of waste, and appropriate waste classification and disposal.

Ongoing tracking of the disposal of non-hazardous and hazardous wastes to confirm they are disposed of appropriately.

For more information visit Section 8.4.6, page 340

Liquid discharges will be released to the marine environment throughout the life of the project.

Planned impacts include:

• Produced formation water
• wastewater and cooling water;
• hydrotest water; and,
• drilling fluids and cuttings.

Unplanned impacts could result from minor accidental releases of chemicals/hydrocarbons to the environment.

Ensuring all planned discharges from vessels comply with requirements.

Implementing ongoing environmental monitoring program and adaptive management framework for produced formation water. 

Selecting chemicals for planned project activities and operations in accordance with the standard selection processes and environmental assessments. 

Ensuring there is no planned discharge of whole synthetic based muds during development drilling.

For more information visit Section 8.4.7, page 346

Planned activities associated with the Crux Project involve the production and transport of large volumes of gas and condensate, and project vessels will carry large volumes of fuel.

There are several ways in which unplanned events (accidents or emergencies) could result in large-scale releases of hydrocarbons including:

• a well blowout during drilling and operations;
• spillage from the process storage on the platform;
• a leak from the export pipeline; and,
• loss of fuel from a vessel.

Shell has strict policies and procedures to avoid the situations outlined above.

While the modelling and mitigation strategies are based on worst-case scenarios occurring, the majority of unplanned spills are significantly smaller.

Ensuring all planned discharges from vessels comply with requirements.

Implementing ongoing environmental monitoring program and adaptive management framework for produced formation water. 

Selecting chemicals for planned project activities and operations in accordance with the standard selection processes and environmental assessments. 

Ensuring there is no planned discharge of whole synthetic based muds during development drilling.

For more information visit Section 8.4.7, page 346

^{*The majority of emissions are accounted for in the design and operation of the Prelude FLNG facility.}