4. Development Alternatives

Transcription

1 32 Browse FLNG Development Draft Environmental Impact Statement 4. Development Alternatives 4.1 Opportunity Realisation The Opportunity and Project Realisation from Exploration to Production (OPREP) process is Woodside s risk based decision framework for opportunities and projects. OPREP provides a process for assessing and refining potential development options, beginning with the opportunity identification through to the operational phase (Figure 4.1). The OPREP process consists of five phases: Assess: Determine whether there is a business justification to progress the opportunity. Select: Select the best concept and define the development scheme sufficiently to commence FEED. Themes are evaluated across a range of technical, commercial, political, economic, environmental and social perspectives. Develop: Finalise scope, cost, schedule and obtain project funding. This phase culminates with the FID which is where the financial commitment is secured and a concept for the design is clearly defined. Execute: Implement the opportunity consistent with scope, cost and schedule. Operate: Operate and evaluate the asset to ensure performance to specifications. Identify new opportunities. Figure 4.1: OPREP Flowchart

2 Section 4 Development Alternatives Select Phase Background Initial Concept Selection Assessment ( ) Woodside conducted a Select phase for the commercialisation of the Browse reservoirs between 2006 and 2009, during which the following five development concepts were identified: Piping Browse gas to the Kimberley for processing onshore (JPP Concept). Piping Browse gas to the Burrup Peninsula for processing onshore. Piping Browse gas to Darwin for processing onshore. Offshore LNG, where processing would take place on a platform at Scott Reef. FLNG, where processing would take place on a floating The Concept Select phase was informed by three types of analysis to ensure a holistic review and comparison of all aspects and impacts of each of the development themes: 1. Technical, financial and volumes analysis: this provided an assessment of the project economic measures which were supported by appropriate technical definition to develop an understanding of key technical risks and opportunities. 2. ESE evaluation: this study provided the foundation of the sustainability assessment component. The ESE evaluation incorporated previous studies and the initial impact assessments and highlighted the key differentiators between each of the concepts. Importantly, stakeholder and community views were captured as inputs to the assessment. The ESE evaluation assessed the performance of each concept against a wide range of ESE criteria to identify the sustainability profile for each. These criteria were weighted by the study team and stakeholders and were used in multi-criteria analysis which incorporated both semi-quantitative and qualitative assessments. 3. Stakeholder engagement: this provided an in-depth analysis of key stakeholder positions and any significant issues with each of the development concepts. At the time the initial Select phase was completed, FLNG had yet to mature as a viable technology, and the JPP Concept was chosen to be progressed through technical and commercial evaluation Concept Review (2013) In April 2013, Woodside announced that the JPP Concept did not meet the company s commercial requirements for a positive FID. Following this decision, the Browse JV participants began a review which comprised the following concepts: Piping Browse gas to the Burrup Peninsula to processing plant onshore. Piping Browse gas to small processing plant onshore Kimberley (smaller capacity than JPP Concept). Piping Browse gas to near shore processing facility on the Kimberley Coast. FLNG. Based on advances made in FLNG technology and business confidence since the Select process, and supported by the outcomes of the concept review process, Woodside advised the ASX on 2 September 2013 that Browse JV participants had selected the use of FLNG technology as the development concept to be progressed to the Develop phase. A semi-quantitative study carried out by Shell to compare the environmental footprint of FLNG relative to an equivalent onshore LNG plant indicated that overall FLNG technology has a smaller environmental footprint than more traditional onshore development themes. The key to the reduced environmental footprint of the FLNG technology is that it combines the traditional offshore and onshore components of an LNG development into a single, integrated FLNG facility, and in doing so: Avoids the need for installation of a pipeline to shore. Eliminates resultant land and seabed disturbance associated with clearing and seabed dredging. Reduces installation and operational risks in sensitive coastal and nearshore marine environments. Reduces volumes of construction materials required (sum of steel, concrete, asphalt, earth and rock), as well as offering the possibility for the facility itself to be refurbished and re-used at the completion of the project life cycle Concept Selection Assessment Summary A comparative description of development themes, encompassing all concepts assessed to date, key matters of NES and associated impacts, is presented in Table 4.1.

3 34 Browse FLNG Development Draft Environmental Impact Statement Table 4.1: Comparative Assessment of Development Themes Presence of Infrastructure FLNG Theme FLNG facility mooring systems, subsea drill centres, wellheads and flowlines located predominantly offshore, away from Scott Reef (closest FLNG facility approximately 8 km). Minimal onshore footprint limited to support infrastructure (marine and aviation). Olive ridley turtle Antarctic mink whale Irrawaddy dolphin Shortfin mako Longfin mako Three migratory bird species including the little tern Infield facilities away from Scott Reef (approximately 6 km) with interfield pipelines connecting these facilities to a Central Processing Facility (CPF) on the continental shelf. Export pipelines connecting the CPF to an onshore/nearshore processing and export Onshore/nearshore facilities including gas processing, accommodation, wastewater treatment and marine facilities. Dugong Indo-pacific humpback whale Australian snubfin dolphin Spotted bottle nose dolphin (Arafura/Timor Sea population) Three sawfish species including freshwater sawfish Three shark species including northern river shark and whale shark Golden bandicoot Greater bilby Golden backed tree-rat Australian painted snipe Masked owl Salt water crocodile Sixty-seven migratory bird species including the little tern Two Ramsar wetlands: Eightymile Beach and Roebuck Bay Commonwealth Marine Area Commonwealth threatened ecological community monsoon vine thicket Offshore LNG Central gas processing complex on Scott Reef (south-east corner of the south Scott Reef lagoon) and infield platforms and interfield pipelines in close proximity to Scott Reef. Minimal onshore footprint limited to support infrastructure (marine and aviation). The risk of environmental impact from the presence of infrastructure is low due to: Torosa facilities (closest to sensitive receptors) located approximately 30 km east of a green turtle nesting/aggregation area (Sandy Islet) and away from pygmy blue whales migration route and humpback whale migration corridor. No infrastructure located on Scott Reef. Seabed footprint required for subsea infrastructure and mooring systems represent approximately 67 ha. Areas of potentially impacted seabed are in deep waters, and are well represented in the region with losses representing a very small fraction of the widespread available habitat. Development infrastructure locations and operational activities minimises impacts to Australian commercial fisheries and Indonesian fishing activities. Risk of environmental impact associated with proximity of the Torosa infield facility to Sandy Islet and pygmy blue whale migration route is similar to FLNG theme. Smaller and fewer facilities are required at the Torosa reservoir but overall increase in infrastructure footprint (additional footprint required for facility gravity boxes, interfield pipelines, CPF and export pipelines). Benthic habitats and associated biota potentially impacted by the placement of infrastructure and stabilisation techniques are similarly well represented in the region. Additional risk of environmental impact, including environmental impacts to sensitive species (e.g. migrating humpback whales), associated with nearshore activities such establishment of a port for onshore concept (i.e. dredging) and/ or gravity boxes for nearshore concept, and installation of pipeline to processing Additional risk of environmental impact to marine and terrestrial flora and fauna and their habitats (including a Commonwealth threatened ecological community monsoon vine thicket) from development footprint associated with onshore facilities, dredging and clearing of approximately 1,500 ha of native vegetation. Additional risk of environmental impact from interaction with other users in nearshore areas due to interfield and export pipelines passing through established Australian commercial fishing areas. Similar risk of impact to Indonesian fishing activities. Additional risk of environmental impact to sensitive nearshore habitats associated with elevated suspended sediment levels resulting from pipeline trenching and port dredging activities. Additional risk of impact to visual amenity in nearshore/onshore environment, including to the Broome community. Additional risk of environmental impact due to facilities being wholly located immediately adjacent to Sandy Islet (green turtle nesting/aggregation area). Similar risk of interaction with cetacean species due to distance from pygmy blue whale and humpback whale migration corridors. Additional development footprint associated with infrastructure location on Scott Reef, resulting in direct loss of coral habitat, not widely represented in the region (only found at other coral atolls such as Seringapatam Reef, Rowley Shoals). Additional exclusion zone around facilities on Scott Reef restricting access to the reef area to Indonesian fishermen during all phases of the development. Additional temporary exclusion zones in place during construction will exclude Australian commercial fishing vessels from a small proportion of their current fishing areas. Additional risk of seabed disturbance impacts due to subsea infrastructure being located on Scott Reef, which has a higher productivity and ecological significance than deep water areas. The distance from key migration routes and turtle nesting/aggregation areas. Small footprint of seabed disturbance offshore. No nearshore component and no infrastructure on Scott Reef. Low risk of impact on commercial fisheries and Indonesian fishers during operations. Areas of seabed at potential risk of environmental impact are well represented in the wider region. Limited onshore footprint (related only to supply chain and logistics support).

4 Section 4 Development Alternatives 35 Vessel Movements FLNG Theme Drill rig and installation and support vessel movements during drilling and installation, and LNG carriers and condensate tankers for export from offshore facilities during operations, occurring in offshore, deep waters, away from Scott Reef. Drilling, construction, installation and supply vessels related to development at the gas reservoirs. Pipelay and associated vessels to install the export and interfield pipelines. Nearshore construction and supply vessels for the onshore LNG facility and associated port facilities. LNG tankers nearshore for export from the onshore Offshore LNG Drilling, construction installation and supply vessels related to development at the gas reservoirs. LNG facility located offshore during operation. LNG tankers for export from the offshore Antarctic mink whale Irrawaddy dolphin Shortfin mako Longfin mako Three migratory bird species including the little tern Dugong Indo-pacific humpback whale Australian snubfin dolphin Spotted bottle nose dolphin (Arafura/Timor Sea population) Three sawfish species including freshwater sawfish and dwarf sawfish Three shark species including northern river shark and whale shark Salt water crocodile Sixty-seven migratory bird species including the little tern Two Ramsar wetlands: Eightymile Beach and Roebuck Bay Commonwealth threatened ecological community monsoon vine thicket The risk of environmental impact from vessel movements is low due to: Little interaction with other vessels as nearshore LNG/condensate tanker movements not required and offshore operations outside of main shipping routes. No routine drilling, installation or operational activities within Scott Reef lagoon. Temporary exclusion zone in place around drill rig will exclude Australian commercial fishing vessels from a small proportion of their current fishing areas. Movements away from key migration routes and turtle aggregation areas. Additional risk of environmental impact due to increased vessel movements in nearshore waters resulting in interactions with listed species (e.g. migrating humpback whales) during operation. Additional risk of impact to Australian commercial fishing activities due to temporary exclusion zones in place during construction in particular during pipelay activities due to their extent. Additional risk of environmental impact associated with construction activities nearshore (jetties, ports and extensive pipelay) including vegetation clearing of a Commonwealth threatened ecological community monsoon vine thicket. Additional risk of environmental impact due to increased vessel movements around Scott Reef and within the Scott Reef lagoon during all phases of the development. The distance from key migration routes and turtle nesting/ aggregation areas. Distance from main shipping routes. No tanker movements inshore/ nearshore. No inshore/nearshore exclusion zones. No routine drilling, installation or operational activities within Scott Reef lagoon. Risk of minor, temporary impacts on commercial fisheries and Indonesian fishers during drilling and installation.

5 36 Browse FLNG Development Draft Environmental Impact Statement Table 4.1 continued: Comparative Assessment of Development Themes Artificial Light FLNG Theme Functional and navigational lighting for vessels, drill rig and FLNG facilities during installation and operation. Flaring from drill rig and FLNG facilities during drilling and installation and periodically in operations. Antarctic mink whale Irrawaddy dolphin Shortfin mako Longfin mako Three migratory bird species including the little tern Functional and navigational lighting for vessels, drill rig, infield platforms and CPF during construction and operation. Flaring from drill rig, infield platforms and CPF during construction and operation. Onshore facilities will also require functional lighting during construction and operation. Flaring induced lighting will also occur. Dugong Indo-pacific humpback whale Australian snubfin dolphin Spotted bottle nose dolphin (Arafura/Timor Sea population) Three sawfish species including freshwater sawfish and dwarf sawfish Three shark species including northern river shark and whale shark Golden bandicoot Greater bilby Golden backed tree-rat Australian painted snipe Masked owl Salt water crocodile Sixty-seven migratory bird species including the little tern Two Ramsar wetlands: Eightymile Beach and Roebuck Bay Offshore LNG Functional and navigational lighting for vessels, drill rig, infield platforms and the Scott Reef central gas processing complex during construction and operation. Little tern Streaked shearwater Flaring from drill rig, infield platforms and Scott Reef central gas processing complex during construction and operation. The risk of environmental impact from artificial light is low due to: Risk of localised behavioural disturbance to fish, seabirds, migratory shorebirds and/or turtles expected during temporary activities required in proximity to Sandy Islet, e.g. drilling. Low risk of environmental impact to sensitive receptors from routine light emissions associated with operation of FLNG facilities due to distance from Scott Reef and Sandy Islet (approx. 30 km). Similar risk of environmental impact to seabirds or migratory shorebirds and fish from light emissions from rigs, platforms and vessels during construction and operation. Additional risk of lighting impacts on population centres associated with processing facilities and vessel movements in nearshore/onshore environments. Additional risk of lighting impacts from infrastructure in close proximity to sensitive marine receptors (i.e. Sandy Islet) at all stages of the development due to the facility being located on Scott Reef. Distance from Scott Reef and Sandy Islet. Isolation from population centres.

6 Section 4 Development Alternatives 37 Noise Emissions FLNG Theme Drilling of production wells. Installation and commissioning activities, drill rig, vessel and helicopter movements mostly in offshore waters. Operational FLNG facilities, LNG carriers and condensate tankers and subsea infrastructure in offshore waters. Construction and commissioning activities, drilling, seabed preparation activities and vessel and helicopter movements in offshore and nearshore waters. Operational infield platforms, continental shelf CPF and subsea infrastructure in offshore waters. Onshore processing Offshore LNG Construction and commissioning activities, drilling, seabed preparation activities, and vessel and helicopter movements. Operational infield platforms, the Scott Reef central gas processing complex and subsea infrastructure at gas reservoirs. Antarctic mink whale Irrawaddy dolphin Shortfin mako Longfin mako Three migratory bird species including the little tern Pygmy blue whale Dugong Indo-pacific humpback whale Australian snubfin dolphin Spotted bottle nose dolphin (Arafura/Timor Sea population) Three sawfish species including freshwater sawfish and dwarf sawfish Three shark species including northern river shark and whale shark Golden bandicoot Greater bilby Golden backed tree-rat Australian painted snipe Masked owl Salt water crocodile Sixty-seven migratory bird species including the little tern Two Ramsar wetlands: Eightymile Beach and Roebuck Bay Little tern Streaked shearwater The risk of environmental impact from noise emissions is low due to: Low risk associated with minor behavioural impacts on receptors such as cetaceans, fish and turtles from underwater noise emissions during operation due to distance of FLNG facilities and associated vessel movements (e.g. tankers) from sensitive habitat (e.g. Scott Reef, Sandy islet). Low risk associated with temporary and localised effects on seabirds from helicopter movements. Majority of installation activities away from Scott Reef. No extensive pipelay activities between offshore infrastructure and the mainland. No development activities in nearshore waters or onshore. Similar risk of environmental impact to marine fauna from underwater noise generated by drilling, installation and operation activities in offshore waters. Similar risk of environmental impact to birds from helicopter movements. Additional risk of environmental impact from underwater noise to sensitive species (e.g. cetaceans) associated with nearshore construction activities required to lay the export pipeline and establish a port (e.g. piling) in support of onshore processing Additional risk of impact associated with construction and operation of onshore processing Additional risk of environmental impacts associated with underwater noise generated by additional noise sources (e.g. pipeline, drilling, construction, and operating facilities) on Scott Reef, in closer proximity to sensitive marine receptors (e.g. turtles and cetaceans). Operational underwater noise emissions resulting in a risk of localised and minor impacts on marine fauna. Isolation from population centres and nearshore migratory routes.

7 38 Browse FLNG Development Draft Environmental Impact Statement Table 4.1 continued: Comparative Assessment of Development Themes Invasive Species FLNG Theme Movements and ballast water exchange from vessels and FLNG facilities offshore. The risk of environmental impact from invasive species is medium due to: FLNG facility and associated vessel operations approximately 8 km from Scott Reef. No installation activity required in nearshore waters of mainland. Routine vessel movements during operation in deep waters away from Scott Reef. No tanker movements entering nearshore waters of mainland during routine operations. Movements and ballast water exchange from vessels and rigs offshore, in the South Scott Reef lagoon and in coastal areas. Onshore processing State threatened marine ecological community Two Ramsar wetlands: Eighty-mile Beach and Roebuck Bay Additional risk of environmental impact from IMS due to offloading operations and increased offshore construction effort, in closer proximity to Scott Reef. Additional risk of environmental impact from IMS introduction in the vicinity of the onshore processing facility due to nearshore construction required to establish a port and increased vessel movements entering coastal waters. Offshore LNG Movements and ballast water exchange from vessels and rigs in close proximity to Scott Reef. Additional risk of environmental impact from invasive marine species (IMS) due to increased vessel movement and development activities at Scott Reef. Liquid and Solid Discharges and Wastes FLNG Theme FLNG facilities and vessels during all phases of the development, largely in offshore waters. The risk of environmental impact from liquid and solid discharges and wastes is low due to: Routine sewage discharge volumes associated with offshore manned FLNG facilities away from Scott Reef. Cooling water and PW discharge approximately 8 km away from Scott Reef. No routine offshore disposal of solid waste generated on FLNG facilities. Infrastructure and vessels during all phases of the development, in offshore and nearshore waters. Extensive pipeline hydrotesting. Onshore processing Commonwealth threatened ecological community monsoon vine thicket Two Ramsar wetlands: Eighty-mile Beach and Roebuck Bay Additional risk of environmental impact associated with larger volumes of produced water (PW) discharged at infield platforms in closer proximity to Scott Reef. Similar risk of environmental impact associated with lower sewage discharges (due to fewer personnel) from operating facilities, in closer proximity (approximately 2 km) to Scott Reef. Similar risk of environmental impact associated with lower cooling water discharge volumes at infield platforms, but in closer proximity to Scott Reef. Additional risk of environmental impact to water quality associated with larger hydrotest and PW discharge volumes. Offshore LNG Facilities and vessels at Scott Reef during all phases of the development. Additional risk of environmental impacts associated with wastes and discharges due to discharge locations in close proximity to Scott Reef. Lack of nearshore construction effort. Location of FLNG facilities and vessel movements of export carriers in deep water away from Scott Reef. Export carriers not entering mainland coastal waters. Discharges occurring in deep offshore waters, away from Scott Reef. No discharges in nearshore and onshore environments. Smaller pipeline network results in lower hydrotest discharge volumes.

8 Section 4 Development Alternatives 39 Atmospheric Emissions FLNG Theme Drill rig, installation vessels and support vessels during drilling and installation. FLNG facilities, LNG carriers and condensate tankers and support vessels during operations. Drill rig, construction and support vessels during drilling and construction. CPF, interfield and export pipelines and support vessels during operations. Onshore processing Offshore LNG Drill rig, construction and support vessels during drilling and construction. Scott Reef central gas processing complex at Scott Reef, interfield pipelines and support vessels during operations. The risk of environmental impact from atmospheric emissions is low due to: Low risk of environmental impact to regional air quality from air emissions associated with the FLNG facilities and support vessels. Majority of air emissions will be offshore, away from population centres. By locating all infrastructure over the reservoir, a long pipeline to shore is avoided which reduces the transport compression requirements and associated greenhouse emissions. Similar risk of environmental impact to regional air quality from air emissions associated with the offshore infrastructure and support vessels. Additional risk of environmental impact associated with air emissions in proximity to population centres. Locating several LNG trains in a single location allows sharing of utilities (e.g. power generation) across trains, thus improving plant greenhouse efficiency compared to FLNG theme. Higher greenhouse efficiency gas turbine power generation due to proven operation onshore. Similar risk of environmental impact to regional air quality from air emissions associated with the processing facility and support vessels. Majority of air emissions will be offshore, away from population centres. Sharing of utilities (e.g. power generation) across trains in one location results in improved greenhouse efficiency compared to FLNG theme. Compression related greenhouse emissions associated with supporting long flowlines from Brecknock/Calliance to the Scott Reef processing theme due to the isolation of the facility from population centres and proximity to reservoirs.

9 40 Browse FLNG Development Draft Environmental Impact Statement Table 4.1 continued: Comparative Assessment of Development Themes Accidental Spills FLNG Theme Drilling of production wells. Infield Development with Onshore/ Nearshore Processing Offshore LNG Transfer, handling, storage or use of chemicals on vessels and FLNG facilities. Use and/or production and storage of hydrocarbons on FLNG facilities. Transfer, handling, storage or use of chemicals on vessels and platforms in both offshore and nearshore environments and at onshore processing Use and/or production of hydrocarbons at gas reservoir infrastructure/platforms and continental shelf CPF and at onshore processing Transfer, handling, storage or use of chemicals on vessels and platforms. Use and/or production of hydrocarbons at gas reservoir infrastructure Scott Reef central gas processing complex. Antarctic mink whale Dugong Indo-pacific humpback whale Australian snubfin dolphin Spotted bottle nose dolphin (Arafura/Timor Sea population) Irrawaddy dolphin Shortfin mako Longfin mako Three migratory bird species including the little tern Three sawfish species including freshwater sawfish and dwarf sawfish Three shark species including northern river shark and whale shark Salt water crocodile Sixty-seven migratory bird species including the little tern Two Ramsar wetlands: Eighty-mile Beach and Roebuck Bay Commonwealth threatened ecological community monsoon vine thicket Little tern Streaked shearwater The risk of environmental impact from accidental spills is medium to high due to: High risk of environmental impact in the event of a loss of well control during drilling due to proximity to Scott Reef. Medium risk of environmental impact in offshore environment associated with loss of containment during offloading, refuelling and vessel collision. No risk of environmental impact from a spill associated with export pipelines to shore. No risk of environmental impact from a spill associated with hydrocarbon loading/ offloading and transport in nearshore environment. Medium risk of environmental impact from loss of containment during condensate offtake/transport in offshore waters. Similar risk of environmental impact associated with loss of well control during drilling. Additional risk of environmental impact from a spill in the nearshore environment associated with loss of containment from export pipelines and during loading from onshore processing Additional risk of nearshore loss of containment during condensate offtake/ transport. Similar risk of environmental impact associated with loss of well control during drilling. Additional risk of environmental impact anticipated due to increased hydrocarbon related processes and infrastructure located on Scott Reef, as well as offloading adjacent to the reef. Similar risk of environmental impact from a spill in nearshore environment due to lack of pipeline to onshore processing facility and reduced vessel movements. Overall Assessment FLNG assessed as most favourable Reduced risk of environmental impact associated with hydrocarbon storage nearshore. Reduced risk of environmental impact associated with hydrocarbon export in pipelines. Segregated condensate storage rather than single inventory that cannot be isolated in export pipeline.

10 Section 4 Development Alternatives Browse FLNG Development Alternatives Do Nothing or Partial Development Alternative The Browse JV participants, as titleholders of the retention leases covering the Browse FLNG Development, are required to undertake activities required to achieve the earliest commercialisation of the Browse resources. Consistent with this, Woodside is nearing finalisation of the BOD phase for the Browse FLNG Development and targeting completion of FEED 12 months post-bod completion. As Scott Reef is directly above part of the Torosa reservoir, the subsea layout has been optimised to balance the risk of environmental impact and efficient hydrocarbon extraction. This has been achieved by locating drill centres within the channel between North and South Scott Reef and utilising horizontally deviating wells to reach locations in the reservoir that would otherwise require on-reef development. The development theme proposed in the Draft EIS, utilising FLNG technology to extract hydrocarbon resources at all three reservoirs (Brecknock, Calliance and Torosa) is therefore currently considered to be the most likely commercially viable option for the development of the Browse gas reservoirs. Partial development of the resources would affect the commercial viability of the project Alternatives for Assessment As part of the approval process under the EPBC Act, there are no alternatives to the FLNG Development theme being proposed for detailed assessment. In addition, there is no concept alternative proposed to be assessed other than using up to three FLNG facilities to develop hydrocarbon resources at Brecknock, Calliance and Torosa.