EP Summary Fugro Geophysical Technical Gorgon Expansion

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    Gorgon Gas Development Fourth Train Expansion Project, Geophysical and Geotechnical Site Survey   Page 1 Environment Plan Public Summary

    GEOPHYSICAL AND GEOTECHNICAL SITE SURVEYGORGON GAS DEVELOPMENT FOURTH TRAIN EXPANSION PROJECT

    ENVIRONMENT PLAN: PUBLIC SUMMARY

    This summary of the Environment Plan for the Gorgon Gas Development Fourth Train Expansion ProjectGeophysical and Geotechnical Site Survey, which will be acquired on the North West Shelf (NWS) offshorefrom Western Australia (WA), has been submitted to the National Offshore Petroleum Safety andEnvironmental Management Authority (NOPSEMA), to comply with Regulations 11(7) and 11(8) of theOffshore Petroleum and Greenhouse Gas Storage (Environment) Regulations 2009.

    INTRODUCTION

    The geophysical and geotechnical survey company Fugro Survey Pty Ltd proposes to undertake ageophysical and geotechnical site survey (Geophysical and Geotechnical Site Survey, Gorgon GasDevelopment Fourth Train Expansion Project), on the NWS offshore from WA. The proposed geophysicaland geotechnical site survey comprise both shallow and deep water components in Commonwealth watersoffshore from Barrow Island (Figure 1), and will be conducted to support marine aspects of Chevron’sGorgon Gas Development Fourth Train Expansion Project. The key objective of the site survey is to gathersufficient geophysical and geotechnical information to provide Chevron with detailed data for the design andlocation of subsea structures and pipelines.

    The geophysical and geotechnical site survey is scheduled to occur in the period between November 2012and April 2013, with expected durations of approximately eight weeks for the geophysical fieldwork and 12weeks for the geotechnical fieldwork.

    COORDINATES OF THE PROPOSED ACTIVITY

    The proposed geophysical and geotechnical site survey will take place within a number of areas associatedwith the Gorgon Gas Development Fourth Train Expansion Project in Commonwealth waters on the NWS,offshore from Barrow Island, WA. This will include both shallow water (water depth range 25-200 m) anddeep-water (water depth range 200-1,397 m) components (Figure 1). Data acquisition will take place in anoperational area that covers ~7,180 km

    2, which overlaps parts of 35 petroleum titles. Boundary coordinates

    for the operational area polygon, which encompasses all of the proposed site survey areas (Figure 2), areprovided in Table 1 below.

    Table 1: Geophysical and geotechnical site survey operational area  – boundary coordinates

    PointLatitude (S) Longitude (E)

    Degrees Minutes Seconds Degrees Minutes Seconds

     A 19 46 36.01 114 05 02.95B 19 46 36.01 114 02 09.59

    C 19 32 46.39 114 03 12.34

    D 19 31 09.25 114 07 14.08

    E 19 30 38.22 114 10 55.72

    F 19 35 21.82 114 30 04.17

    G 19 58 10.57 115 11 22.77

    H 20 40 14.11 115 20 56.38

    I 20 41 58.54 115 12 26.84

    J 20 38 13.24 115 07 28.03

    K 20 11 18.58 114 41 20.16Datum: WGS84

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    Figure 1: Location map  – geophysical and geotechnical site survey, Gorgon Gas DevelopmentFourth Train Expansion Project

     At the closest point (Point H  –  see Figure 1), the geophysical and geotechnical site operational area is

    situated at a minimum distance of approximately 1.2 km from the WA State waters boundary, andapproximately 7.3 km from the west coast of Barrow Island. All components of the operational area arelocated in Commonwealth waters. At the closest point, the inshore components of the operational area

    located approximately 6.5 km from the northern boundary of the Barrow Island Marine Park, andapproximately 1.2 km from the boundary of the Barrow Island Marine Management Area. Water depths in theoperational area range from ~25-1,397 m. There are no emergent features or shallow shoals or banks withinthe operational area (Figure 1).

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    Figure 2: Geophysical and geotechnical survey components

    DESCRIPTION OF THE PROPOSED ACTIVITY

    The geophysical and geotechnical site survey is scheduled to occur in the period between November 2012and April 2013, with expected durations of approximately eight weeks for the geophysical fieldwork and 12weeks for the geotechnical fieldwork. Timing of commencement of the geophysical and geotechnicalfieldwork is dependent on fair sea state conditions suitable for data acquisition, the availability of the surveyvessel for conducting the survey, and granting of approvals from the appropriate government bodies.

    The site survey proposed is a typical geophysical and geotechnical survey similar to most others conductedin Australian marine waters (in terms of technical methods and procedures). No unique or unusualequipment or operations are proposed.

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    Geophysical ComponentThe geophysical site survey will use both vessel-based and autonomous underwater vehicle (AUV)-basedsurvey sensors (multi-beam echo sounder, sub-bottom profiler; sidescan sonar) to acquire and process datato provide the following:

      Bathymetry: Accurate bathymetry (water depth measurements) via the acquisition of echo sounderand multi-beam echo-sounder data in conjunction with speed or sound in water measurements.

      Seabed topography: Multi-beam bathymetry data will provide a topographic map over the operationalarea outlining areas of differing water depth.

      Seabed heterogeneity:o  side scan sonar data will be used to determine areas of the seabed with contrasting acoustic

    properties that relate to different seabed sediment composition, sedimentary features androck outcrops; and

    o  such features often are associated with changes in seabed depth and so the multi-beamderived topographic map will be used to augment interpretation.

      Seabed/shallow sub-surface mechanical properties: Sediment samples acquired via drop core orgrab-sampler are required to ‘ground-truth’ the various seabed sediment types identified by the side -

    scan sonar to understand the nature of contrasting seabed types.  Seabed obstruction/contact map: The side scan sonar will locate any significant seabed anomaly

    present within the operational area such as geological features or manmade debris.

      To map the shallow subsurface geology: The chirp and boomer or sparker sub-bottom profilingsystems will identify any subsurface geological feature that may provide impediments to proposedconstruction activities. Maps will be created to chart the location of these features.

    Geotechnical ComponentThe purpose of the geotechnical site survey is to gather sufficient site-specific geotechnical data for thedesign and installation of subsea production equipment (wellheads, manifolds, umbilicals, flowlines, exportpipelines) during the front end engineering design (FEED) phase of the Gorgon Gas Development FourthTrain Expansion Project. The geotechnical site survey will incorporate: cone penetration testing; T-bartesting; drilling and sampling; rock coring; piston coring; and box coring.

    The work scope for the geotechnical site survey is divided into two operations: shallow geotechnicalinvestigation; and deep geotechnical investigation. Both field investigations will be performed from adedicated geotechnical survey vessel.

    The shallow geotechnical investigation encompasses all of the pipeline routes locations as well as thegeohazard study and a portion of the scarp crossing. The deep geotechnical investigation encompasses thepiezo cone penetrometers tests (PCPT) and boreholes up to 40 m below the seabed at the subsea structurelocations, pipeline crossings and scarp crossing.

    Survey VesselFugro proposes to conduct the geophysical and geotechnical site survey using a purpose-built geotechnicalsurvey vessel, the MV Fugro Synergy , which is a dynamically positioned (DP), multi-purpose drilling, well

    intervention and geotechnical vessel. The Fugro Synergy  has all necessary certification/registration and isfully compliant with all relevant MARPOL and SOLAS convention requirements for a vessel of this size andpurpose, including a Shipboard Oil Pollution Emergency Plan (SOPEP) in accordance with Regulation 37 of

     Annex I of MARPOL 73/78. During the survey, the Fugro Synergy  will be refuelled in port in Dampier. No atsea refuelling will take place during the survey. All crew changes and resupply of the vessel will take place inport.

    DESCRIPTION OF THE RECEIVING ENVIRONMENT

    The operational area for the proposed geophysical and geotechnical site survey is located in the CarnarvonBasin on the NWS (Figures 1 and 2), approximately 150 km west of Dampier. The NWS is scattered withislands, the largest of which is Barrow Island. The operational area is situated within the North-west MarineRegion (NWMR), and overlaps parts of three key ecological features (KEF) for the NWMR:

      Ancient coastline at 125 m depth contour.

      Continental Slope Demersal Fish Communities.

      Exmouth Plateau.

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    Physical EnvironmentThe Pilbara Region is characterised by two seasons: summer (September  – April) and winter (May – August).The southern portion of the NWS region, including Barrow Island, is characterised by an arid, subtropicalclimate. In summer, mean daily temperatures range between 20°C and 34°C. During winter, mean daily

    temperatures range between 17°C and 26°C. Relative humidity at Barrow Island ranges from 61% in thewinter months (September) to 70% in the summer (February).

    Meteorological records from Barrow Island are detailed and are likely to be indicative for the region. Given itsposition in relation to the operational area, meteorological conditions on Barrow Island are considered toprovide a good proxy for conditions likely to be encountered in the operational area. Rainfall on BarrowIsland varies significantly each year and is dependent on rain-bearing low-pressure systems, thunderstormactivity, and the passage of tropical cyclones (which generally occur from November to April). Averageannual rainfall at Barrow Island is 306 mm with most rain (85%) occurring between January and July. Themean ambient wind speed around Barrow Island during summer is 6.6 m/s, and the maximum summer windspeed is 16.2 m/s. The dominant wind directions during summer are from the south-west and west. Duringwinter, winds approach from the east, south, and south-west and have a mean speed of 5.8 m/s and amaximum speed of 19.4 m/s.

     An average of five tropical cyclones per year occur in the Pilbara Region, with an average of two per yearpassing through the Barrow Island area. According to the Bureau of Meteorology, the Australian tropicalcyclone season runs from 1 November to 30 April, with cyclones most common between December andMarch. Tropical cyclones are unpredictable in occurrence, intensity, and behaviour and can generateextreme seas and swell. Large increases in precipitation are associated with cyclones, and the Bureau ofMeteorology reports that rainfall totals greater than 100 mm are common with tropical lows that move overland.

    In the deep waters of the operational area, water temperatures at depths greater than 500 m range from asummer peak of approximately 10°C to a winter low of about 4°C. The mean temperature for depthsbetween 200 and 250 m is approximately 10°C. Surface water temperatures offshore range betweenapproximately 20°C in winter and 31°C in summer. Water circulation in the region is influenced by the

    southward-flowing Leeuwin Current and the Indonesian Throughflow. Currents in the operational area areprincipally driven by semidiurnal tidal forcing. The direction of tidal currents is a flood flow towards the south-west and an ebb flow towards the north-east. Local winds can influence water circulation, more so in theupper 200 m of the water column. Maximum current speeds in upper regions of the water column (surface to100 m deep) near the operational area are predicted to range from 0.33 to 0.8 m/s in non-cyclonic conditionsand may occasionally approach 1.1 m/s under extreme storm conditions.

    The region typically experiences a persistent winter swell of around 2 m, generated by low-pressure systemsin southern latitudes. During winter, strong easterly winds can also generate 2 m seas. Both swell and seastend to be smaller during summer. Astronomical tides on the NWS are semidiurnal and generally quite large,ranging from 0.95 m near Exmouth to more than 3 m on the inner shelf near Broome. Maximum spring tideamplitudes range from just over 2 m at Exmouth, 2.5 m at Onslow, 4.5 m at Dampier, to nearly 6 m at PortHedland.

    The continental slope (the scarp), extends from 300 m to 1,200 m water depth and is divided into an upper,middle and lower slope based on distinctive changes in the seabed gradient and morphology. At the base ofthe scarp, maximum seabed slopes of up to 80° can be found. Average slopes in the upper scarp are 4° to5°, while the average slope of the middle and lower scarp is more benign (2° to 5°).

    Biological EnvironmentThe operational area for the geophysical and geotechnical site survey includes deep-water environments (upto 1,397 m deep) at the most north-easterly point in the adjacent to the Io/Jansz gas field and, closer toBarrow Island, shallow water marine habitats in water as shallow as 25 m.

    The deep-water habitats of the operational area are generally depauperate and typical of the low abundance,richness and diversity observed in other deep areas of the NWS. However, there are areas of increased

    infaunal abundance in deeper water depths, as evidenced by areas of heavily bioturbated sediments,indicating an active infaunal assemblage (see below). Benthic surveys conducted in depths ranging from 212m to more than 1,300 m, showed that no epifauna (i.e. fauna living on the seabed) were recorded from themajority of samples (63%) and infauna, where present, were in low abundance, with low richness and

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    diversity. Surveys conducted in the scarp region found that the soft sediment in the area was often markedby burrow holes made by unidentified organisms (thought to be small fish or crustaceans); these softsediments supported some benthic life, including solitary sea pens, holothurians, and hydroids. Soft coralswere present and were found to be most abundant at depths between approximately 550 and 700 m, with

     Alcyonian soft corals being the most common taxa identified. At these sites, the soft corals were found inmixed communities with bryozoans, sponges, and hydroids.

    The benthic habitats in State waters off the west coast of Barrow Island largely comprise unvegetated orbare sand, or alternatively, sand covering a gently sloping limestone pavement. Macroalgae coverrepresents the dominant ecological element and the dominant habitat assemblage in the shallow StateWaters off the west coast of Barrow Island, with macroalgal taxa common within the local area and thePilbara Region. Corals in the area are present in low abundances and only sparsely scattered colonies ofspecies such as the hard coral Turbinaria spp. were recorded. Coral reefs are limited to the southern andcentral parts of the west coast. Biggada Reef on the central west coast of Barrow Island is an extensive,largely intertidal coral reef that extends to the subtidal zone.

    Two rocky reef sections occur approximately 25 km and 12 km from Barrow Island, in 50 –55 m and 40 m

    water depths, respectively. The inner platform reef supports scattered corals and sponges, although the areais too deep to support well-developed benthic primary producer assemblages. The outer reef supportsencrusting sponges and scattered deep water coral. Small, sparse patches of seagrass occur on sandveneers at a few locations in shallow waters on the west coast of Barrow Island and at low levels ofpercentage cover, growing in mixed assemblages with macroalgae and occasionally benthicmacroinvertebrates. No mangroves were recorded on the west coast of Barrow Island.

    Small pelagic fish are believed to comprise a significant proportion of the fish biomass throughout the region,feeding on pelagic phytoplankton and zooplankton and providing a food source for a wide variety ofpredators including large pelagic fish, sharks, seabirds, and marine mammals. Fish species of the inner shelfinclude lizardfish, goatfish, trevally, angelfish, and tuskfish. Large pelagic fish (such as tuna, deep lizardfish,deep goatfish, ponyfish, deep threadfin bream, adult trevally, billfish, mackerel, swordfish, and marlin) arealso found in the region, mainly in water depths of 100 to 200 m, and occasionally on the continental shelf.

    The region also contains a rich variety of chondrichthyan fish (sharks, skates and rays), which occupy abroad range of shallow and deep-water habitats, as well as being distributed throughout the water column.

    The NWS region is associated with important populations of demersal fish species, including commercialspecies such as snappers, emperors, and groupers, which are distributed across a number of distinct depthranges, specifically areas of the upper slope (225 –500 m water depth) and mid slope (750 –1,000 m waterdepth). More than 508 fish species have been identified on the slope in this area, of which 64 species areendemic.

    Demersal fish surveys were undertaken off the west coast of Barrow Island as part of the Gorgon FoundationProject, in macroalgal, soft sediments with sessile non-coral benthic macroinvertebrates, and unvegetatedsand communities. These surveys were undertaken in water depths between 12 and 22 m. During the firstsurvey in March 2009, a total of 698 individuals from 58 species and 28 families were recorded; in

    February/March 2010, 1,266 individuals from 71 species and 31 families were recorded. The results fromsurveys undertaken in 2008 and 2009 indicated that different shallow water marine habitats surroundingBarrow Island were generally characterised by different species compositions and richness. Elasmobranchspecies, including sharks and possibly sawfish, are likely to be present in the geophysical and geotechnicalsite survey operational area.

    Protected Marine Fauna A review of the Environment Protection and Biodiversity Conservation Act 1999  (EPBC Act) database(Protected Matters search tool) held by the Department of Sustainability, Environment, Water, Populationand Communities (DSEWPaC) was conducted for the geophysical and geotechnical site survey operationalarea polygon (Figure 2).

    The 10 listed Threatened species that may occur in, or relate to, the operational area are:

    1. the southern giant petrel;2. the blue whale;3. the humpback whale;4. the short-nosed sea snake

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    5. the loggerhead turtle;6. the green turtle;7. the leatherback turtle;8. the hawksbill turtle;

    9. the flatback turtle; and10. the whale shark.

    The operational area is not considered a habitat that is critical to the survival of any listed species. Similarly,there are no EPBC Act-listed threatened ecological communities (TECs) in the vicinity of the operationalarea.

    Whales and DolphinsThe EPBC Act database lists 26 cetacean species that may occur in, or may relate to, the operational area,all of which are protected under the Act; one of which is also classified as Endangered, one as Vulnerableand eight as Migratory species. There are no known feeding or breeding areas for these listed species withinthe geophysical and geotechnical site survey operational area, so these species are likely to be transient.

    Humpback whales are regular visitors to Pilbara offshore waters, moving through Barrow Island watersbetween June and October on their annual migration between their feeding grounds in Antarctic waters andtheir calving grounds in the more northerly Pilbara and Kimberley waters. Northbound humpback whalestend to remain on or within 200 m water depth, while southbound whales tend to come closer to BarrowIsland, generally occurring between 50 m and 200 m water depth. Humpback whales are more common inwaters off the west coast of Barrow Island (Figure 3), but also visit the east coast.

     Another species of whale that may be occur in, or relate to, the operational area as indicated from the EPBC Act database search is the blue whale. Blue whales are widely distributed throughout the worlds’ oceans.This species has been recorded offshore in all states excluding the Northern Territory. Their migration pathsare widespread and do not clearly follow coastlines or particular oceanographic features. The blue whale israrely present in large numbers outside recognised aggregation areas. Blue whales are believed to calve intropical waters in winter and births peak in May to June, however the exact breeding grounds of this species

    are unknown.

    The operational area and adjacent waters do not include any known blue whale feeding, breeding or restingareas. In the NWMR, pygmy blue whales migrate along the 500 m to 1,000 m depth contour on the edge ofthe slope, and are likely to be feeding on ephemeral krill aggregations. The northward component of thismigration takes place from May to mid-August, with a peak in July-August, and the southward componentoccurs from late October to November-December, with a few isolated individuals moving south in January.The migration appears to be centred on the 500 m depth contour. Consequently, it is possible that bluewhales may be encountered in the operational area and adjacent waters, given the proposed survey timingand the water depth range in the deeper parts of the operational area (200-1,397 m).

    Other cetacean species whose broad distributions cover the region include whales that are infrequentlyobserved usually restricted to cooler or deeper waters (e.g. killer and Bryde’s whales) and are unlikely to be

    encountered in the operational area during the survey in significant numbers. Sperm whales tend to be foundin offshore waters and may occasionally visit the shelf waters offshore of Barrow Island.

    DugongDugong are known to occur around Barrow Island, the Lowendal Islands, and the Montebello Islands.Population estimates suggest that approximately 2,000 individuals of this species occur in the region.Dugong populations are greater in Exmouth Gulf and Shark Bay than around offshore islands. Dugongshave been observed in the shallow waters surrounding Barrow Island, including in the vicinity of theshallower waters of the geophysical and geotechnical site survey operational area. Due to the absence ofsignificant seagrass habitats, dugongs are likely to frequent the operational area only during transit tofeeding grounds elsewhere in the Pilbara Region.

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    Figure 3: Humpback whale migration routes in the vicinity of the operational area for the sitesurvey

    TurtlesBarrow Island is a regionally important nesting area for green turtles and flatback turtles. Flatback turtlenesting on Barrow Island is concentrated on the mid-east coast on deep, sandy, low-sloped beaches withwide, shallow, intertidal zones. The nesting period for flatback turtles extends from October to March, with apeak nesting period in December and January. Flatback turtle hatchlings emerge from their nests six to eightweeks after eggs are laid. The hatching period occurs from January to April, with the peak hatching period inFebruary and March.

    The green turtle reproductive population at Barrow Island is estimated at around 20,000 females, comprisingan important proportion of the NWS genetic stock. Mating aggregations occur along the west coast of BarrowIsland from August to January, with the peak period from September to December. Green turtles tend to neston the west, north, and north-east coasts of Barrow Island where beaches are high-energy, deep, steeply

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    sloped, sandy, and have an unobstructed foreshore approach. The nesting period for green turtles on thewest coast of Barrow Island occurs between October and April and peaks between December and February.The green turtle hatching period occurs between November and May and peaks in February and March. Themating aggregation season takes place between August and January, peaking between September and

    December. Green turtles are herbivorous and graze on algae growing on intertidal rock platforms on the westcoast of Barrow Island.

    Barrow Island is not considered a regionally important nesting site for hawksbill turtles, which favour small,shallow beaches typically characterised by coarse-grained sand or coral grit interspersed with rocks andbeach wrack for nesting. Hawksbill turtles nest on beaches on the east coast of Barrow Island, and have themost seasonally diffuse nesting cycle; individuals may nest at any time throughout year. However, the mainnesting period for hawksbill turtles extends from July to February, with peak nesting time during October andNovember. The olive ridley turtle and leatherback turtle have not been recorded, and the loggerhead turtlehas rarely been seen, in Barrow Island waters and on Barrow Island beaches.

    Sea SnakesSea snakes are generally common in waters west of Barrow Island and in waters between Barrow Island and

    the mainland. Although they are highly mobile and can cover large distances, many species are restricted torelatively shallow coastal waters. Most sea snakes have shallow benthic feeding patterns and are rarelyfound in water depths exceeding 30 m. However, very little is known about the distribution of the individualspecies of sea snakes in the region. There are 14 protected species of sea snake listed as marine speciesunder the EPBC Act that may occur in the operational area. The short-nosed sea snake is also listed asCritically Endangered the EPBC Act, and may be present in the operational area as it has been identified asbeing present in the region. The olive sea snake is a common inhabitant of the waters around Barrow Islandand the shallow Rowley Shelf.

    Sharks and Ray-finned FishesElasmobranch species, including sharks, are likely to be present in the operational area for the geophysicaland geotechnical site survey. To date, none of these species has been recorded during baseline marinesurveys conducted since 2007 in the vicinity of the approved Gorgon Foundation Project Marine Facilities.

    Whale sharks may pass through the deeper waters off Barrow Island occasionally; however, they do notaggregate there. There are no known up-welling areas, or other spatially restricted feeding habitats, in thevicinity of the operational area. Although there are no records of the whale shark’s presence in theoperational area there have been sightings in the region, and they are known to occur in both tropical andtemperate waters and are normally oceanic and cosmopolitan in their distribution. The tracks of three whalesharks tagged at Ningaloo Reef in 2005 passed through the operational area to the north-west of BarrowIsland, and it is possible that they may be encountered during the proposed site survey.

    Thirty-five species of pipefish, seahorse and seadragon may occur in the geophysical and geotechnical sitesurvey operational area. These species may be widespread through the shallower benthic habitats of theBarrow Island area. The operational area does not include any spatially restricted habitats and is notexpected to be of particular significance to these species. The rock pipefish is known to occupy shallow rock

    pools along the east coast of Barrow Island.

    Seabirds and ShorebirdsSeabirds undertaking foraging activities may pass through the offshore areas of the geophysical andgeotechnical site survey operational area. Studies suggest that Barrow Island is both a staging site (an areawhere migrating birds gather to feed before continuing on their migration) and an important non-breeding sitefor migratory shorebirds. Shorebirds are widely distributed around Barrow Island, which is an internationallysignificant site for six migratory shorebird species (ruddy turnstone, sanderling, red-necked stint, grey-tailedtattler, greater sand plover, and lesser sand plover) and two non-migratory species (fairy tern and sootyoystercatcher). The highest abundances of shorebirds occur on the south-eastern and southern coasts ofBarrow Island.

    Protected Areas The closest protected areas to the operational area are the Montebello/Barrow Islands Marine ConservationReserves (Figure 4).

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    Figure 4: Montebello/Barrow Islands Marine Conservation Reserves

    These reserves are comprised of three separately vested reserves, namely the Montebello Islands MarinePark, Barrow Island Marine Park and Barrow Island Marine Management Area, which were gazetted in 2004.The social values of these conservation areas include hydrocarbon exploration and production, pearling,nature-based tourism, commercial fishing, recreational fishing, water sports, European history/maritimeheritage, and scientific research. Many of these social values are highly dependent upon the maintenance ofthe above mentioned ecological values. With the exception of Barrow Island (which does not have publicaccess), these conservation areas attract visitors who participate in activities such as fishing, diving, wildlifeviewing, island exploration, and surfing. Visitor numbers to the conservation areas are low and are

    concentrated around the Montebello Islands.

     At the closest point, the inshore components of the geophysical and geotechnical site operational area (PointH, see Figure 1) are located approximately 6.5 km from the northern boundary of the Barrow Island Marine

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    Park, and approximately 1.2 km from the boundary of the Barrow Island Marine Management Area ( Figure4).

    The Commonwealth Government has finalised its proposal to gazette the Montebello Commonwealth Marine

    Reserve, north-west of Barrow Island (Figure 4). The proposed marine reserve covers over an area ofapproximately 3,413 km2, in waters depths ranging from approximately 15 m to 150 m. The key ecological

    feature of the proposed reserve is the ancient coastline, which is a unique seabed feature that providesareas of enhanced biological productivity. The area acts as a foraging area for migratory seabirds and formarine turtles, and also includes part of the migratory pathway of the humpback whale. The proposedreserve includes shallow shelf environments and provides protection for shelf and slope habitats, as well aspinnacle and terrace seabed features. The rocky reef occurring approximately 12 km west from BarrowIsland is located within the proposed reserve.

    The operational area for the proposed geophysical and geotechnical site survey overlaps a portion of thewestern side of the proposed Commonwealth marine reserve, within petroleum exploration permit area WA-391-P (Figure 4).

    Socio-Economic EnvironmentCommercial Fisheries

     Although commercial fishing is limited in the Montebello/Barrow Islands marine conservation reservescommercial fishing does occur in the broader Pilbara Region, including areas within the operational area forthe proposed geophysical and geotechnical site survey. These fisheries include the:

      Commonwealth Managed Fisheries: North West Slope Trawl Fishery, Western Tuna and BillfishFishery, Southern Bluefin Tuna Fishery, Western Skipjack Tuna Fishery, and Western DeepwaterTrawl Fishery.

      State Managed Fisheries: Northern Demersal Scalefish (Pilbara Region), North Coast Shark Fishery,Pearl Oyster Managed Fishery, Beche-de-mer Fishery, Marine Aquarium Fish Managed Fishery.

      Other regional fisheries: Exmouth Gulf Prawn Managed Fishery, Gascoyne Demersal ScalefishFishery, and Gascoyne and Pilbara Coast Blue Swimmer Crab Fishery.

    Pearling activities are also undertaken in the region north of Barrow Island. However, there are no pearlingareas/zones crossed by the operational area. The nearest active pearl farm is located near the MontebelloIslands, ~23 km from the closest boundary of the site survey operational area.

    The Commonwealth fisheries are managed by the Australian Fisheries Management Authority (AFMA). Ofthese five fisheries listed above, only the North West Slope Trawl Fishery (NWSTF) is active in the deepercontinental slope waters off the NWS. The NWSTF operates off north-western Australia from 114°E to125°E, roughly between the 200 m isobath and the outer boundary of the Australian Fishing Zone. TheNWSTF has traditionally targeted scampi and deep-water prawns. However, in recent years, Australianscampi has been the main target of the fishery. Demersal trawl gear is used in the NWSTF. Fishing forscampi occurs over soft, muddy sediments or sandy habitats, typically at depths of 350 –600 m on thecontinental slope. Two vessels were active in the fishery in 2009 –10, with Australian scampi being the maintarget. Recent effort in the fishery has been dominated by a small number of vessels based in WA.

    Whilst the operational area for the geophysical and geotechnical site survey overlaps a small part the south-western area fished by the two vessels operating in the NWSTF in 2009-2010, it is apparent that most of theeffort and catch within the fishery occurs in shallower, upper slope waters (350-600 m) well to the north-eastof the operational area—especially to the south-west and north-east of the Rowley Shoals.

    Recreational Fisheries

    Recreational fishing is a popular pursuit among local residents of the Pilbara Region—it is managed by theWA Department of Fisheries through a variety of management tools that aim to limit catches to sustainablelevels. Closer to Barrow Island, recreational fishing is less common, mainly due to the remoteness of thearea. The areas of highest recreational fishing activity in the Montebello/Barrow Island Marine Conservation

    Reserves are reported to be off the north-eastern end of Trimouille Island and in the waters south of theMontebello group. No recreational fishing is expected to occur in the deeper, offshore waters of theoperational area.

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    Petroleum Exploration and ProductionThe proposed geophysical and geotechnical site survey overlap parts of 35 petroleum titles. Petroleumexploration and production, including seismic surveys and the drilling of exploration wells, is an ongoingactivity within many of these title areas. There are a number of subsea pipelines and wellhead platforms

    within or adjacent to operational area for the site survey, including:

      East Spar manifold and pipeline and John Brookes unmanned platform and pipeline; and

      Wonnich and Harriet pipelines (with their associated topside monopods and wellhead platforms).

    ShippingThere are shipping channels in the waters surrounding Barrow Island and overlapping the operational areafor the proposed geophysical and geotechnical site survey. These shipping channels are required for theexisting WA Oil operation activities on Barrow Island, the Gorgon Foundation Project, and the shippingactivities from Dampier and Port Hedland. Figure 5 shows the areas of increased commercial vessel activity

    within and adjacent to the operational area.

    Figure 5: Areas of increased commercial vessel activity

    Cultural Heritage Archival sources suggest that a number of significant vessels have been lost in the Barrow Island region and

    there is potential for lugger shipwreck sites in the vicinity of Barrow Island. The earliest known shipwreck ofEuropean origin within Australian waters (the Trial , wrecked around 1622) is located approximately 43 kmnorth of Barrow Island and 17 km north-west of North West Island in the Montebello Islands (Figure 6). TheTrial  wreck site is located ~12 km from the boundary of the operational area for the site survey.

     Another historic shipwreck site in the vicinity of the proposed operations is that of the Wild Wave, a Chinesebrig wrecked in 1873. This shipwreck site is located ~50 north-west of the Montebello Islands, just inside thegeophysical and geotechnical site survey operational area (Figure 6).

    Records indicate that there are no known shipwreck sites along the Gorgon Foundation Project subseapipeline routes, and marine underwater video survey work and reviews of the side-scan sonar results supportthis.

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    Figure 6: Identified shipwrecks in the waters surrounding the Montebello Islands 

    Native TitleThere are no registered Native Title claims or determinations over the waters surrounding Barrow Island oroverlapping the operational area for the proposed geophysical and geotechnical site survey.

    National HeritageThere are no places listed on the Commonwealth Heritage List or the Register of National Estate within orimmediately adjacent to the operational area for the proposed geophysical and geotechnical site survey.

    TourismDue to the water depths over most of the site survey operational area, and distance to coastal areas of thePilbara, there are no recreational activities (such as recreational fishing and marine-based tourism)undertaken in the area.

    Defence ActivitiesThe operational area for the proposed geophysical and geotechnical site survey does not overlap anydefence training or military exercise areas.

    MAJOR ENVIRONMENTAL HAZARDS AND CONTROLS

     An Environmental Risk Assessment (ERA) has been undertaken to understand and manage theenvironmental risks associated with the proposed geophysical and geotechnical site survey to a level thatminimises impacts on the environment and meets the objectives of the survey. The risk assessment hasbeen undertaken to identify the sources of risk (aspects) and potential environmental impacts associatedwith the activity and to assign a level of significance or risk to each impact. This subsequently assists inprioritising mitigation measures to ensure that the environmental impacts are managed to As Low AsReasonably Practicable (ALARP).

     A summary of the key sources of environmental risk (aspects) for the proposed activity include:

      use of low and mid-frequency acoustic sources;

      light generation from the survey vessel;  interactions of the survey vessel with marine fauna;

      anchoring or grounding of the survey vessel;

      dragging or loss of towed or seabed-deployed equipment;

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      drilling and coring of the seabed;

      emissions to atmosphere from the survey vessel;

      discharge of ballast water and survey vessel biological fouling;

      routine discharge of wastewater and waste to the ocean from the survey vessel;

      accidental discharge of hydrocarbons and chemicals to the ocean from the survey vessel;  vessel collisions resulting in fuel and oil spills, and/or damage to benthic habitats;

      interactions with commercial fishing and shipping; and

      operation of the survey vessel within, or in the vicinity of, protected and heritage areas.

     A summary of the potential environmental impacts associated with the above sources of environmental riskinclude:

      disturbance to marine fauna including cetaceans, turtles, fish and benthic epifauna;

      disturbance to the seabed and benthic habitats and communities;

      localised reduction in water quality from drilling and coring activities;

      reduced air quality from atmospheric emissions as a result of operation of machinery and use ofinternal combustion engines;

      introduction of invasive marine species as a result of ballast water discharge and vessel biologicalfouling;

      marine pollution from routine discharges including sewage water, bilge water and other solid wastes;

      marine pollution from accidental discharges including hydrocarbon spills and hazardous materials;

      disturbance to social and community values due to interactions with commercial fishing vessels andshipping; and

      disturbance to heritage and conservation values.

    The environmental aspects of the geophysical and geotechnical site survey that have the potential to causesignificant environmental effects have been determined through an evaluation of the proposed activity, thesurrounding environment including specific sensitivities and values, and legislative requirements. Theseenvironmental aspects are:

      accidental discharge of hazardous materials;

      accidental fuel and oil spills from the survey vessel; and

      vessel collisions, resulting in fuel and oil spills and/or damage to benthic habitats.

    Implemented control measures documented in Table 2 ensures that the environmental risks associated withthese impacts are maintained at ALARP levels, while maintaining economic viability for the proposed activity.These control measures are taken into consideration in calculating the residual risk associated with thepotential environmental impacts.

    MANAGEMENT APPROACH

    The design and execution of the proposed geophysical and geotechnical site survey will be conducted under

    the framework of the Fugro-TSM Environmental Policy and Vessel Management System. Thegeophysical/geotechnical survey programme will be supported by Fugro Marine Services EmergencyResponse Manual Vessel, and a project-specific HSE Plan, that has been compiled by Fugro Survey.

    Fugro will apply a tiered approach to optimising the environmental performance of the project and ensuringthat Fugro’s environmental standards and performance objectives are achieved. The approach involvesidentification of local and regional environmental sensitivities, prioritisation of risks, determination ofappropriate practices and procedures to reduce those risks, and clear designation of roles andresponsibilities for implementation.

     A series of plans, procedures and work instructions will be used for the proposed geophysical andgeotechnical site survey to ensure that appropriate management measures are applied as required tominimise the risk of environmental disturbance from operations. The plans, procedures and work instructions

    are documented within corporate systems/manuals developed by Fugro as well as documents writtenspecifically for the site survey (e.g. project-specific HSE Plan). Many of the procedures apply to all vessels inthe Fugro fleet, however the associated work instructions are generally vessel specific.

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    Fugro is responsible for ensuring that the proposed geophysical and geotechnical site survey is managed inaccordance with the Implementation Strategy described in the Environment Plan and the Fugro-TSM VesselManagement System. Given the control measures that will be implemented for all environmental aspects ofthe survey, the risk of significant adverse environmental effects from the proposed geophysical and

    geotechnical site survey has been assessed as low for all aspects, apart from discharge of hazardousmaterials, fuel and oil spills and vessel collisions, which have been assessed as medium.

    The implementation of specific marine fauna monitoring and encounter procedures will be used to minimisethe potential for any adverse effects to whales. These procedures are consistent with applicablerequirements of the Australian Commonwealth Government Guidelines: EPBC Act Policy Statement 2.1  – Interaction between offshore seismic exploration and whales  (September 2008). A precautionary 300 mshutdown zone for whales will be applied for use of low and mid-frequency acoustic sources during the sitesurvey—i.e. if a whale/s is sighted or enters within 300 m of the survey vessel or surface towed geophysicalequipment, the acoustic source will be shut down completely. Specific vessel-whale interaction procedureswill also be applied for non-acoustic source operations.

    Owing to their migratory habits, all five species of turtle that may occur in the operational area and

    surrounding waters have the potential to be present in open ocean habitats throughout the operational area,albeit in low densities. Whilst the shallow water areas of the operational area do include features that may befeeding areas for turtles (i.e. coral reef areas), the density of animals is likely to be low, and as such theprobability of impacts on turtles is also low. It is unlikely that turtles would use this area for any significantperiod of time and survey activities are unlikely to significantly affect the population of any marine turtlespecies. The operational area is not located close to any locations important for seabird or shorebirdbreeding or feeding.

    The survey is unlikely to have any significant effects on benthic communities due to the water depths acrossmost of the operational area, and the absence of any significant or sensitive benthic habitats or communities.

     Anchoring of the survey vessel will only occur in emergency circumstances, and the vessel is fitted withhighly sophisticated position fixing equipment.

    Shallow water geotechnical operations during the site survey will involve a seabed blockdrive PCPT, gravitypiston coring and box coring. Deep-water geotechnical operations during the will involve use of the drillingsystem aboard the Fugro Synergy . Drilling will be performed using standard straight flush rotary methodswithout a riser, and seawater or guar gum will be used as a drilling fluid (water-based mud - WBM). Theseabed in the inshore and offshore components of the operational area will be subject to localised physicaldisturbance during PCPT, coring and drilling operations. The area of seabed to be disturbed at each siteduring seabed sampling and/or testing operations is very small and comprises of the borehole and thefootprint of the cores/samples taken. It is expected that any impacts on the seabed as a result of the surveyactivities will be minor and have only a short-term effect. The geotechnical sampling and testing programmeis of low intensity and affects only a very small area of seabed at each location.

    The geotechnical site survey will involve the discharge of a small amount of drill cuttings and mud to themarine environment. There is potential for drill cuttings to smother a small area of seabed and as such

    possibly generate anoxic conditions in the sediments over time. However, any smothering effects on thesparse benthic communities in the operational area would be highly localised and on a small scale,particularly given the borehole depths only range from 20 –40 m and the borehole diameter is ~25 cm. As theseabed sediments and benthic communities in the operational area are uniform and widespread throughoutthe NWS, the consequences of changes to these communities in the vicinity of the drilling locations can beconsidered to be low.

    During the survey, the Fugro Synergy  will be refuelled in port in Dampier. No at sea refuelling will take placeduring the survey. Hence, the probability of diesel fuel spills from transfer operations is zero. The riskassessment and mitigation/management measures described in the Environment Plan clearly demonstratethat the environmental impacts and risks of fuel and oil spills associated with the proposed geophysical andgeotechnical site survey have been reduced to ALARP, and that these impacts and risks are of anacceptable level. This conclusion has been reached on the basis of a number of factors, including:

      the low likelihood of a large diesel spill occurring in the first place;

      the low probability of exposure of sensitive resources (e.g. green turtles and coral communities onthe west coast of Barrow Island) to surface slicks or entrained oil;

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      the very conservative thresholds applied in the risk assessment for surface slicks or entrained oil—i.e. there is a very low probability that surface slicks or entrained oil at these concentrations wouldcause significant environmental effects to any sensitive resources; and

      the limited spatial and temporal extent of survey activities in the south-east corner of the operational

    area, close to shallow waters and shorelines, relative to the overall extent and duration of the activity(i.e. operations in shallow, inshore waters close to Barrow Island represent only a small proportion ofoverall survey activities).

    CONSULTATION PLAN

    Consultation with stakeholder groups concerning Fugro’s proposed geophysical and geotechnical site surveyfor the Gorgon Gas Development Fourth Train Expansion Project has taken place, primarily within thecommercial fishing industry, during the preparation of the Environment Plan, and prior to the commencementof the survey. The following organisations have been contacted and informed of the proposed operations:

      A Raptis and Sons

      Austral Fisheries

      Australian Fisheries Management Authority  Australian Hydrographic Service

      Australian Maritime Safety Authority

      Centre for Whale Research

      Commonwealth Fisheries Association

      Department of Broadband, Communications and the Digital Economy

      Department of Sustainability, Environment, Water, Population and Communities

      Geoscience Australia

      MG Kailis

      National Native Title Tribunal

      Northern Fishing Companies Association

      Recfishwest

      Shark Bay Seafoods  Telstra

      TunaWest

      WA Department of Environment and Conservation

      WA Department of Fisheries

      WA Department of Mines and Petroleum

      WA Department of Transport

      WA Fishing Industry Council

      WA Marine Parks and Reserves Authority

      WestMore Seafoods

    Consultation with all of the stakeholders listed above, plus any others identified during the consultationprocess, will continue during and after the survey, if necessary.

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    Table 2: Summary of environmental risks and management approach for key aspects of the proposed geophysical and geotechnical site survey

    Impact category Potential impacts Control and mitigation measures Residual risk level

    Disturbance to marinefauna

    Cetaceans - behaviouralreactions (avoidance, diving,increased dive times)

    Disturbance to marine turtles,fish communities, and seabirds

      Adherence to EPBC Act Policy Statement 2.1:  300 m shut-down zone for acoustic sources

      Application of vessel-whale interaction procedures for non-acoustic energy sourceoperations

      External lighting of survey vessel will be minimized to that required for navigation, vesselsafety and safety of deck operations, except in the case of emergency

      Operational area is located at least 7.3 km away from any beaches and adjacent shallow

    waters important for turtle nesting, hatching and breeding  Operational area is not located close to any locations important for seabird or shorebird

    breeding or feeding

      Survey will not be operating over critical habitat for feeding, spawning, breeding ormigrating fish populations

    Low

    Disturbance to benthichabitats

    Small localised disturbance toepibiota in event of loss ofequipment

      Survey will be conducted in water depths of ~25-1,397 m away from any shallow waterareas or significant/sensitive benthic habitats and communities

      No anchoring of the survey vessel will take place during survey unless in an emergency

      All reasonable efforts taken to retrieve lost equipment

      Recording and reporting of all items lost overboard

    Low

    Introduction of invasivemarine species

    Introduction and establishmentof invasive marine species withconsequent impacts on benthiccommunities, fisheries etc.

      Survey vessel required for the proposed activity will not discharge ballast water

      Adherence the Australian Ballast Water Management Requirements, if necessary

      The survey vessel has all the necessary AQIS clearances to operate unrestrictedanywhere in Australian waters

    Low

    Marine pollution fromroutine discharges

    Localised temporary decrease

    in ambient water quality fromdischarge of sewage, greywater, putrescible wastes andbilge water

      All sewage and putrescible wastes will be handled and disposed of in accordance withMARPOL Annex IV

      Discharge of sewage and putrescibles waste will be of short duration with high dispersion

    and biodegradability  Sewage and putrescible wastes macerated where possible prior to disposal

      All sewage and putrescible waste treatment systems and holding tanks are to be fullyoperational prior to survey commencement

      Relevant discharge requirements for treated and untreated sewage are adhered to (>3nm from land for treated sewage; >12 nm from land for untreated sewage)

    Low

    Marine pollution fromaccidental discharges

     Acute toxicity effects on marinefauna, such as marine turtles,fishes and seabirds, fromaccidental discharges ofhazardous materials

      Harmful Packaged Substances handled and disposed of in accordance with MARPOL Annex V

      Waste Stream Management Plan in place detailing wastes generated and disposalrequirements

      No discharge of plastics or plastic products of any kind from survey vessel

      All solid, liquid and hazardous wastes (other than sewage, grey water and putrescible

    Medium

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