6 POTENTIAL IMPACTS RELATED TO NORMAL OPERATIONS

Transcription

1 SLR Environmental Consulting (Namibia) (Pty) Ltd Page POTENTIAL IMPACTS RELATED TO NORMAL OPERATIONS This chapter describes and assesses the significance of potential impacts of normal well drilling operations. This assessment was preceded by the Scoping Phase in which screening was conducted of the potential interactions of the proposed project with biophysical and socio-economic resources/receptors according to the following categories: No interaction, where the proposed project is unlikely to interact with the resource/receptor; Minor negative interaction, where there is likely to be an interaction, but the resultant effect is unlikely to change baseline conditions in an appreciable way; Moderate/major negative interaction, where there is likely to be an interaction and the resultant impact is likely to have a reasonable potential to cause a significant effect on the resource or receptor; or Positive interaction, where there is likely to be a positive interaction and the resultant impact has a positive effect on the resource or receptor. The project specific interactions matrix (see Table 3-1) presents the results of this screening. Those with no interaction have been scoped out for further consideration in the EIA process. The remaining interactions have been subjected to a detailed assessment. The methodology used to determine the significance of potential impacts is presented in Appendix 5. The application of the Mitigation Hierarchy is central to the impact assessment that was used. The identification of enhancement measures was considered in parallel to the identification of mitigation measures. The impacts that remain following mitigation are assessed and presented as residual impacts. The status of all impacts should be considered to be negative unless otherwise indicated. The assessment of impacts is structured as follows: Section 6.1: Impacts on the bio-physical environment; Section 6.2: Impact on the socio-economic environment; Section 6.3: Cumulative impacts; and Section 6.4: Impact Summary. Potential impacts related to unplanned activities or accidents (upset conditions) and the No-Go alternative are assessed in Chapter 7 and 8, respectively. 6.1 IMPACTS ON THE BIO-PHYSICAL ENVIRONMENT EMISSIONS TO THE ATMOSPHERE Description of the source of impact The table below summarises project activities likely to emit pollutants to the atmosphere and affect air quality. Project phase Mobilisation Operation Demobilisation Activity Transit of drilling unit and support vessels to drill site Operation of drilling unit at the drill site and transit of support vessels and helicopters between the drilling unit and Lüderitz (port and airport) Incineration of waste Well testing (optional for appraisal well only) Transit of drilling unit and support vessels from drill site

2 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-2 Emissions from these activities are as follows: Exhaust gas emissions produced by the combustion of gas or liquid fuels in turbines, boilers, compressors, pumps and other engines for power and heat generation can be the most significant source of air emissions from offshore facilities. Fugitive emissions associated with leaking tubing, valves, connections, flanges, open-ended lines, pump seals, compressor seals, pressure relief valves or tanks, and hydrocarbon loading and unloading operations. Vent or flaring off some of the oil and gas brought to the surface during well testing. Flaring and venting ensures gas and other hydrocarbons are safety disposed of in the event of an emergency, power or equipment failure or other plant upset conditions. Incineration of waste on board the drilling unit and support vessels. Description of the environmental aspects The release of gaseous pollutants, principally carbon dioxide (CO 2 ), oxides of nitrogen (NO x ), oxides of sulphur (SO x ) and carbon monoxide (CO), together with lesser quantities of particulate matter (PM10/PM2.5) and volatile organic compounds (VOCs), from the drilling unit, support vessels and helicopters have the potential to cause short-term reductions in local air quality close to the emissions source. Description of the potential impact Some of these compounds could have a negative physiological effect on marine fauna (direct impact), as well as contribute to global greenhouse gas emissions (secondary impact). Receptors Emissions from activities described above would primarily take place at the well location and along the route taken by the support vessels and helicopter between the drilling unit and Lüderitz (port and airport). The drilling activities would be located in the offshore marine environment, more than 200 km offshore, far removed from any sensitive receptors (e.g. settlements, bird or seal colonies, etc.). Thus, such emissions would not have a direct effect on any receptor or other activity, other than the drilling unit itself. Project Controls and Industry Practice Shell would ensure that the proposed drilling operation is undertaken in a manner consistent with good international industry practice. Shell s HSSE & SP Control Framework standards require that project vessels comply with the emission criteria within MARPOL 73/78 Annex VI, which prohibits the: deliberate emission of Ozone Depleting Substances; and incineration of certain products, such as contaminated packaging materials and polychlorinated biphenyls (PCBs). Shell will strive to comply with the requirements set out in MARPOL Annex VI Reg , by using ISO 8217 fuel. However, this depends on the constant availability of Low Sulphur Marine Gas Oil (maximum sulphur content of 0.1%) from the closest Namibian port. The project would also comply with Shell s HSSE & SP Control Framework standards with regards to Ozone Depleting Substances. This standard requires the following: Identification of all Ozone Depleting Substances and maintenance of an inventory until Ozone Depleting Substances are eliminated. Elimination of halons and hard chlorofluorocarbons (HCFCs) in all operations by end-of-year 2010 and HCFCs by beginning-of-year Removal of Ozone Depleting Substances from Non-Sealed Systems. Provision of controls to prevent the loss of Ozone Depleting Substances.

3 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-3 Provision of controls for the recovery and destruction of Ozone Depleting Substances. Avoid the transfer of Ozone Depleting Substances to third parties for re-use. Where permitted by legislation, in-company transfers and transfer to Halon banks are permitted. Provision of controls to ensure that new installations are not fitted with HCFCs. Provision of terms that comply with the requirements above in contracts for the purchase, service or disposal of equipment or refrigerant that contains Ozone Depleting Substances. Ensuring people aware of equipment that contains Ozone Depleting Substances and the controls required before they perform work that could release these substances. Application of the Permit to Work system in order to control work on, or disposal of, equipment that contains Ozone Depleting Substance in line with the requirements above. Performance objectives Contribute to the replenishment of the ozone layer and improve marine atmospheric air quality by fulfilling the requirements of the Montreal Protocol, the International Air Pollution Prevention Certificate and the revised MARPOL Annex VI (shipboard equipment). Impact assessment The release of gaseous pollutants to the atmosphere from proposed activities may cause a short-term reduction in local air quality and a negligible increase in greenhouse gases that would make an insignificant contribution on the global scale. The majority of emissions would occur at the drill site during drilling and well testing, as well as from support vessels and helicopters along the route from the drilling unit and Lüderitz (port and airport). Based on the fuel consumption used in a previous Shell drilling campaign in Tanzania, the average fuel consumption for a two month drilling campaign (including drill ship, three support vessels and a helicopter) is estimated to be in the order of m 3. Typical emissions resulting from this consumption are indicated below. Pollutant Emissions (m 3 ) CO CO 2 NO x 8.3 N 2O 0.1 SO CH VOC 11.7 Although an anchored drilling unit, which uses less fuel than a dynamically positioned unit, would use less fuel and thus result in fewer emissions, an anchored unit is not suitable for the current drilling campaign due to the deep water in the licence area. Flow testing would result in hydrocarbons being burned at the well site. From a global perspective, flaring releases 350 million tons of CO 2 emissions in to the atmosphere per year. Despite the negative perception of flaring, it is one of the safest methods of disposing unwanted hydrocarbons that cannot otherwise be captured and used for other purposes. It allows more harmful gases to be converted to CO 2 during the combustion process, e.g. methane, which is 20 times more effective in trapping heat in the atmosphere than CO 2, would be more harmful to the environment. Flaring produces mainly CO 2 emissions and water vapour. However, if the combustion process in not fully efficient unburnt hydrocarbons would be present, mainly methane (source: The duration of flow testing and the

4 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-4 amount of hydrocarbons produced would depend on the quality of the reservoir, but is kept to a minimum to avoid wasting potentially marketable oil and/or gas. The duration of flaring would be in the order of two days, but this is subject to confirmation when the detailed geology and fluids are known. Although the majority of solid waste would be transported to shore for disposal, certain non-toxic combustible wastes (e.g. galley waste) may be incinerated on the drilling unit and support vessels, creating smoke (particulate matter) emissions. The volumes of solid waste that may be incinerated on board, and hence also the volumes of atmospheric emissions, would be minimal. Given the offshore location of the area of interest, air emissions are expected to disperse rapidly and there is no potential for accumulation of air pollution leading to any detectable long-term impact. The potential impact of emissions due to drilling and associated activities would be localised (or localised at any one time in the case of the support vessels and helicopter), and of limited duration (i.e. two months per well) and low intensity (far removed from any sensitive receptors). The significance of this impact is, therefore, assessed to be very low without mitigation (see Table 6-1). Although emissions would definitely occur as a result of the operation of the drilling unit, support vessels and helicopters, the likelihood of occurrence is considered to be probable due to the far offshore location of the area of interest away from any sensitive receptors. Mitigation In addition to compliance with MARPOL 73/78 Annex VI regulations regarding emissions and Shell s standards regarding Ozone Depleting Substances mentioned above, the following measures would be implemented to reduce emissions at the source: No. Mitigation measure Classification 1 Implement a maintenance plan to ensure all diesel motors and generators receive adequate maintenance to minimise soot and unburnt diesel released to the atmosphere. Avoid/reduce at source 2 Optimise the drilling schedule and supply and support operations/logistics which would minimise the time of the operations. Avoid/reduce at source 3 Implement leak detection and repair programmes for valves, flanges, fittings, seals, etc. Avoid/reduce at source 4 Ensure no incineration of waste occurs within the port limits. Avoid 5 The following pollution prevention and control measures are proposed for gas flaring 4 : 5.1 Use a high-efficiency burner for flaring to maximise combustion of the hydrocarbons in order to minimise emissions and hydrocarbon drop-out during well testing. 5.2 Maximise flare combustion efficiency by controlling and optimising flare fuel/air/stream flow rates. Avoid/reduce at source Residual impact This potential impact cannot be eliminated because the drilling unit, support vessels and helicopters are needed to undertake the drilling programme and require fuels that result in discharges of contaminants to the environment. With the implementation of the project controls and mitigation measures, the residual impact, although with a lower intensity, is considered to remain of VERY LOW significance (see Table 6-1). 4 Based on the International Finance Corporation s (IFC) Environmental, Health and Safety Guidelines for offshore oil and gas development, April 2007.

5 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-5 Monitoring Shell to record and document volumes and type of fuel used, waste incinerated and hydrocarbons flared. Table 6-1: Impact of atmospheric emissions from drilling and associated activities CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Low Very Low to Low Probability Probable Probable Confidence High High Significance Very Low VERY LOW Reversibility Mitigation potential Partially reversible Very Low DISCHARGES OF WASTES TO SEA Normal vessel discharges Description of impact Project activities that would result in normal discharges of wastes to the sea as summarised below. Project phase Mobilisation Operation Demobilisation Activity Transit of drilling units and support vessels to the drill site Operation of drilling unit at the drill site and support vessels between the drilling unit and the onshore logistics base in Lüderitz Drilling unit/support vessels leave drill site and transit to port or next destination Normal discharges to the marine environment are described further below: Deck drainage: Deck drainage consists of liquids from rainfall, sea spray, deck and equipment washing (using water and an approved detergent). Deck drainage would be variable depending on the vessel characteristics, deck activities and rainfall amounts. Machinery space drainage: Vessels occasionally discharge treated bilge water. Bilge water is drainage water that collects in a ship s bilge space (the bilge is the lowest compartment on a ship, below the waterline, where the two sides meet at the keel). Sewage: Discharges of sewage would vary according to the number of persons on board and would be intermittent. The maximum design volume of discharge from sewage treatment system of the drillship (Noble Globetrotter II) is litres per hour (31 L/min). Galley wastes: Galley wastes, comprising mostly of biodegradable food waste, generated on board the project vessels would be discharged over board. The daily discharge from a drilling unit is typically about 0.2 m 3. Cooling water: Seawater would be used as the cooling for generators on board the drilling unit and the heated seawater would be discharged overboard. Opening and closing of the BOP: A further operational discharge is associated with routine well opening and closing operations. It is anticipated that approximately litres of oil-based hydraulic emulsion fluid would be vented per month during the drilling of a well.

6 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-6 Description of the environmental aspects The discharge of wastes to sea could create local reductions in water quality, both during transit and at the drill site. Deck and machinery space drainage may result in small volumes of oils, detergents, lubricants and grease, the toxicity of which varies depending on their composition, being introduced into the marine environment. Sewage and gallery waste would place a small organic and bacterial loading on the marine environment, resulting in an increased biological oxygen demand. Concentrated BOP fluids, which are usually mineral oil- or glycol-water mixes are mildly toxic to crustaceans and algae, but are completely biodegradable within 28 days. Description of the potential impact These discharges would result in the local reduction in water quality, which could impact marine fauna in a number of different ways: Physiological effects: Ingestion of hydrocarbons, detergents and other waste could have adverse effects on marine fauna, which could ultimately result in mortality; Increased food source: The discharge of galley waste and sewage would result in an additional food source for opportunistic feeders, speciality pelagic fish species; and Increased predator - prey interactions: Predatory species, such as sharks and pelagic seabirds, may be attracted to the aggregation of pelagic fish attracted by the increased food source. Although solid waste would not be discharged to sea, the accidental release of solid waste comprising nonbiodegradable domestic waste, packaging and operational industrial waste into the sea could pose a further hazard to marine fauna, may contain contaminant chemicals and could end up as visual pollution at sea, on the seashore or on the seabed. Receptors The operational waste discharges from the activities described above would primarily take place at the drill site and along the route taken by the support vessels between the drilling unit and Lüderitz. The drill site is located in the offshore marine environment, more than 200 km offshore, far removed the NIMPA, coastal islands and any sensitive coastal receptors (e.g. key faunal breeding/feeding areas, bird or seal colonies and nursery areas for commercial fish stocks); however, discharges could still directly affect migratory pelagic species transiting through the area of interest. Vessel discharges on route to the onshore supply base in Lüderitz could result in discharges closer to shore, thereby potentially having an environmental effect on the sensitive coastal environment. The taxa most vulnerable to waste discharges are turtles, pelagic seabirds, large migratory pelagic fish and cetaceans, some of which are considered globally Critically Endangered (e.g. leatherback turtle), Endangered (e.g. black-browed and yellow-nosed albatross, fin, blue and sei whales) Vulnerable (e.g. short-fin mako shark, whitetip shark and sperm whale) or Near threatened (e.g. blue shark). Project Controls and Industry Practice Shell would ensure that the proposed drilling operation is undertaken in a manner consistent with good international industry practice. Shell s HSSE & SP Control Framework standards require that project vessels comply with the applicable requirements in MARPOL 73/78, as summarised below. Sewage and grey water discharges from vessels are regulated by MARPOL 73/78 Annex IV, which specifies the following: > Vessels must have a valid International Sewage Pollution Prevention Certificate. > Vessels must have an onboard sewage treatment plant providing primary settling, chlorination and dechlorination before discharge of treated effluent.

7 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-7 > Discharge of sewage beyond 12 nm requires no treatment. However, sewage effluent must not produce visible floating solids in, nor cause the discolouration of, the surrounding water. > Sewage must be comminuted and disinfected for discharges between 3 nm (± 6 km) and 12 nm (± 22 km) from the coast. This would require an onboard sewage treatment plant or a sewage comminuting and disinfecting system. > Disposal of sewage originating from holding tanks must be discharged at a moderate rate while the ship is proceeding on route at a speed not less than 4 knots. Sewage would be treated using a marine sanitation device to produce an effluent with: > a biological oxygen demand (BOD) of <25 mg l -1 (if the treatment plant was installed after 1/1/2010, e.g. on the Noble Globetrotter II) or <50 mg l -1 (if installed before this date); > minimal residual chlorine concentration of 1.0 mg l -1 ; and > no visible floating solids or oil and grease. The discharge of biodegradable wastes from vessels is regulated by MARPOL 73/78 Annex V, which stipulates that: > No disposal to occur within 3 nm (± 5.5 km) of the coast. > Disposal between 3 nm (± 5.5 km) and 12 nm (± 22 km) needs to be comminuted to particle sizes smaller than 25 mm. Discharges of water (deck drainage, bilge and mud pit wash residue) to the marine environment are regulated by MARPOL 73/78 Annex I, which stipulates that vessels must have: > A Shipboard Oil Pollution Emergency Plan (SOPEP). > A valid International Oil Pollution Prevention Certificate, as required by vessel class. > Equipment for the control of oil discharge from machinery space bilges and oil fuel tanks, e.g. oil separating/filtering equipment and oil content meter. Oil in water concentration must be less than 15 ppm prior to discharge overboard. > Oil residue holding tanks. > Oil discharge monitoring and control system. Performance objectives Contribute to improving marine water quality in the receiving water area by fulfilling the requirements of MARPOL 73/78 standards. Impact assessment The contacted drilling unit and support vessels would have the necessary sewage treatment systems, oil/water separators and food waste macerators to ensure compliance with MARPOL 73/78 standards. Compliance with MARPOL 73/78 means that discharges introduce relatively small amounts of nutrients and organic material to oxygenated surface waters, which would result in a minor contribution to local marine productivity and possibly of attracting some opportunistic feeders. The intermittent discharge of sewage is likely to contain a low level of residual chlorine following treatment, but this is expected to have a minimal effect on seawater quality given the relatively low total discharge and taking into account dilution in the surface waters. The area of interest is located approximately 200 km offshore and is far removed from any sensitive coastal receptors, including the NIMPA. Given the offshore location of the area of interest, waste discharges are expected to disperse rapidly and there is no potential for accumulation of wastes leading to any detectable long-term impact. The closest sensitive receptor is Tripp Seamount, which is located approximately 50 km south-east of the area of interest at its closest point. The dominant wind and current direction would,

8 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-8 however, result in discharges moving mainly in a north-westerly away from the seamount. Thus, discharges are unlikely to have an impact on Tripp Seamount. Due to the distance offshore, it is only likely to be pelagic species of fish, birds, turtles and cetaceans that may be affected by the discharges, some of which are species of conservation concern. The abundance of these species in the area of interest is expected to be low, and they are unlikely to respond to the minor changes in water quality resulting from vessel discharges. The most likely animal to be attracted to the drilling unit would be large pelagic fish species, such as the highly migratory tuna and billfish, which are usually associated with features such as canyons and seamounts. The attraction of pelagic fish species could result in the attraction of other animals, e.g. pelagic seabirds, sharks and odontocetes (toothed whales). Based on the relatively small discharge volumes, offshore location and high energy sea conditions, the potential impact of normal discharges from the drilling unit and support vessels would be of low intensity, short-term duration and mainly limited to the immediate area around the drilling unit (highly localised). The potential impact on the marine fauna is, therefore, considered to be of very low significance without mitigation (see Table 6-2). The majority of these discharges are not unique to the project vessels, but rather common to the numerous vessels that operate in or pass through Namibian coastal waters on a daily basis. Mitigation In addition to compliance with MARPOL 73/78 regulations regarding waste discharges mentioned above, the following measures would be implemented to reduce wastes at the source: No. Mitigation measure Classification 1 Develop a Waste Management Plan for all wastes generated at the various sites (including shore and marine). This should include: separation of wastes at source; recycling and re-use of wastes, where possible; and treatment of wastes at source (maceration of food wastes, compaction, incineration, treatment of sewage and oily water separation). Avoid/reduce at source 2 Discharge sewage effluent more than 5 m below the water surface. Abate on site 3 Implement leak detection and maintenance programmes for valves, flanges, fittings, seals, hydraulic systems, hoses, etc. Avoid/reduce at source 4 Use a low-toxicity biodegradable detergent for the cleaning of all deck spillages. Reduce at source 5 Use drip trays to collect run-off from equipment that is not contained within a bunded area and route contents to the closed drainage system. 6 Dispose of residual oily waste onshore in accordance with the appropriate laws and ordinances. Avoid/reduce at source Abate at receptor Residual impact With the implementation of the project controls and mitigation measures, the residual impact would be INSIGNIFICANT (see Table 6-2).

9 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-9 Table 6-2: Impact of normal discharges on marine fauna CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Low Very Low to Low Probability Probable Possible Confidence High High Significance Very Low INSIGNIFICANT Reversibility Mitigation potential Fully reversible Low Ballast water discharge Description of the source of impact To maintain the stability and trim of the drilling unit and the support vessels, seawater would be pumped into designated ballast tanks and released to sea during mobilisation and transit to site. Project activities are summarised in the table below. Project phase Mobilisation Activity Transit of drilling units and support vessels to the drill site Discharge of ballast water by drill unit and/or support vessels Operation Demobilisation n/a n/a Description of the environmental aspects Depending on where the ballast water is loaded, it may contain larvae, cysts, eggs and adult marine organisms from other locations. Thus, ballasting and de-ballasting of project vessels could lead to the introduction of exotic species and harmful aquatic pathogens to the marine ecosystem. Vessels and the transportation of infrastructure from one location to another also provide the potential for translocation of introduced or alien species. Description of the potential impact Invasive marine species are considered primary drivers of ecological change in that they create and modify habitat, consume and outcompete native fauna, act as disease agents or vectors, and threaten biodiversity and ecosystem function. Receptors The discharge of ballast water from support vessels and drilling units would take place at the drill site, which is located more than 200 km offshore, far removed from any sensitive coastal receptors (e.g. sessile benthic invertebrates, endemic neritic and demersal fish species). Due to the water depths in the area of interest (1 500 m to m), colonisation by invasive species on the seabed is considered unlikely and thus discharge of ballast water at the drill site would not pose a significant threat to natural biodiversity in the deep sea habitats. Project Controls and Industry Practice As the Shell HSSE & SP Control Framework standards do not explicitly discuss ballast water, the project would follow the requirements of the International Maritime Organisation s (IMO) 2004 International

10 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-10 Convention for the Control and Management of Ships Ballast Water and Sediments. The Convention aims to prevent the spread of harmful aquatic organisms from one region to another, by establishing standards and procedures for the management and control of ships' ballast water and sediments. The Convention stipulates that all vessels are required to implement a Ballast Water Management Plan and that all ships using ballast water exchange should, whenever possible, conduct such exchange at least 200 nm (± 370 km) from the nearest land and in water of at least 200 m depth. Where this is not feasible, the exchange should be as far from the nearest land as possible, and in all cases a minimum of 50 nm (± 93 km) from the nearest land and preferably in water at least 200 m in depth. Project vessels would comply with this requirement. Performance objectives Control the spread of non-native invasive species to vulnerable ecosystems. Contribute to improving marine water quality in the receiving water area by fulfilling the requirements of the International Convention for the Control and Management of Ships Ballast Water and Sediments ("the Ballast Water Management Convention"). Impact assessment The drilling unit and the support vessels contracted for the proposed drilling campaign would have spent time outside of Namibia s EEZ prior to drilling. This exposure to foreign water bodies and possible loading of ballast water increases the risk of introducing invasive or non-indigenous species into Namibian waters. The risk of this impact is, however, significantly reduced by the implementation of ballast water management measures in accordance with the IMO guidelines. De-ballasting in the area of interest, which is approximately 200 km from the coast and in water depths great than m, would comply with the IMO s requirement of exchanging ballast water at least 200 nm (± 370 km) from the nearest land and in water of at least 200 m depth. The risk of this impact is further reduced by the highly dynamic, wave-exposed coastline of Namibia, which contributes to minimising the establishment of alien invasive species resulting in comparatively low numbers of such species in the region. Further ballasting and de-ballasting during drilling at the drill site (i.e. at one location) would not pose an additional risk to the introduction of invasive species. The drilling unit and support vessels are also highly unlikely to release contaminated ballast water to sea as these vessels are designed such that ballast water does not come into contact with oily or other contaminated areas. Considering the remote location of the area of interest and compliance with the IMO guidelines for ballast water, the unlikely impact related to the introduction of alien invasive marine species is considered to be of medium intensity in the long-term and of regional to national extent. Once established, an invasive species is likely to remain in perpetuity. The significance of impact is consequently deemed medium to high without mitigation (see Table 6-3). Mitigation In addition to compliance with the requirements of the IMO 2004 Ballast Water Management Convention (including the implementation of a Ballast Water Management Plan), the following measures would be implemented to reduce and manage the potential introduction of alien species in ballast water: No. Mitigation measure Classification 1 Avoid the unnecessary discharge of ballast water. Reduce at source 2 Use filtration procedures during loading in order to avoid the uptake of potentially harmful aquatic organisms, pathogens and sediment that may contain such organisms Avoid/reduce at source

11 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-11 No. Mitigation measure Classification 3 Ensure that routine cleaning of the ballast tank to remove sediments should be carried out, where practicable, in mid-ocean or under controlled arrangements in port or dry dock, in accordance with the provisions of the ship's Ballast Water Management Plan 4 Ensure all infrastructure (e.g. wellheads, BOPs and guide bases) that has been used in other regions is thoroughly cleaned prior to deployment Avoid/reduce at source Avoid/reduce at source Residual impact With the implementation of the project controls and mitigation measures, the residual impact is considered to be of LOW significance. Table 6-3: Assessment of impact related to the potential introduction of alien/invasive marine species through ballast water discharge and equipment transfer CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Regional to National Regional Duration Long-term Long-term Intensity Medium Low Probability Improbable Improbable Confidence Medium Medium Significance Medium to High LOW Reversibility Mitigation potential Irreversible Medium Discharge of cuttings, drilling fluid and cement Description of the source of impact Project activities that would result in accumulation of cuttings, drilling fluid and cement on the seabed are summarised in the table below. Project phase Mobilisation Operation Activity n/a Discharge of drill cuttings and WBM at the well bore during the initial riserless drilling stage Discharge of residual cement during casing installation during the initial riserless drilling stage Discharge of drill cuttings (including residual SBM) from the drilling unit during the risered drilling stage Demobilisation n/a These activities are described further below: During the initial (riserless) drilling stage cuttings and WBM from the top-hole sections would be discharged onto the seafloor where they would accumulate in a conical cuttings pile around the wellhead. It is estimated that approximately m 3 of cuttings and approximately m 3 of WBM would be discharged onto the seafloor during riserless drilling (refer to Table 4-5). After a casing string is set in a well, specially designed cement slurries are pumped into the annular space between the outside of the casing and the borehole wall. During this operation a maximum of 150% of the required cement volume would be pumped into the space between the casing and the borehole wall. Thus, in the worst-case scenario approximately 200 m 3 of cement would be discharged

12 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-12 onto the seafloor. Due to the low temperatures and high pressures at the proposed well depth, the excess cement would dissolve slowly into the surrounding seawater. During the risered drilling stage cuttings from lower hole sections are circulated up the marine riser to the drilling unit, where the cuttings are removed from the returned drill mud and treated to reduce oil content to 6.9% or less of dry cuttings weight before being discharged overboard typically a few metres below the sea surface. Cuttings released from the drilling unit would be dispersed more widely around the drill site by prevailing currents. The total volume of surface released cuttings during the risered drilling stage is estimated to be in the order of m 3 per well, and is dependent on the well design. These cuttings would contain approximately 10 m 3 of residual SBM. Description of the environmental aspects The discharge of drill cuttings, drilling fluids and residual cement would result in the physical disturbance of the seabed sediments and accumulation on the seabed, as well as result in an increase of sediment in the water column. Description of the potential impact The potential impacts associated with the discharge of cuttings, drilling fluid and cement include: Smothering of seabed habitat and associated benthic fauna. Any benthic fauna present on the seabed within the footprint of the discharge may potentially be disturbed or crushed; Toxicity and bioaccumulation effects on marine fauna. Benthic may also suffer indirect toxicity and bioaccumulation effects due to leaching of potentially toxic cement additives; Increased water turbidity and reduced light penetration resulting in indirect physiological effects on marine fauna or indirect effects on primary productivity in surface waters; and Reduced physiological functioning of marine organisms due to indirect biochemical effects. Receptors The discharge of cuttings at the seabed would have both direct and indirect effects on benthic faunal communities living on the seabed or within the sediments in the vicinity of the drill site and within the fall-out footprint of the cuttings plume discharged from the drilling unit. Although the benthic fauna at the water depths encountered in the area of interest (1 500 m to m) is poorly understood, deep water fauna inhabiting unconsolidated sediments is expected to be relatively ubiquitous, usually comprising fast-growing species able to rapidly recruit into areas that have suffered environmental disturbance. Epifauna living on the sediment typically comprise urchins, burrowing anemones, molluscs, seapens and sponges, many of which are longer-lived and, therefore, more sensitive to disturbance. No rare or endangered species are known to occur in the deep water area. In contrast, the benthos associated with hard substrata is typically vulnerable to disturbance due to their long generation times. Such sensitive communities would only be expected to occur at Tripp Seamount and in the adjacent submarine canyon, which are located approximately 50 km south-east of the area of interest at its closest point. Cuttings discharged from the drilling unit would also have both direct and indirect effects on primary producers (phytoplankton) in surface waters and pelagic fish and invertebrate communities in the water column. Due to the offshore location of the area of interest, the abundance of phytoplankton, pelagic fish and invertebrate fauna is likely to be very low. Being dependent on nutrient supply, plankton abundance is typically spatially and temporally highly variable and is thus considered to have a low sensitivity. Higher productivity and the associated development of detritivore-based food-webs can, however, be expected around Tripp Seamount, which is located outside of the deposition footprint.

13 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-13 Project Controls and Industry Practice There are no Namibian regulations governing the discharge of drill cuttings to sea during hydrocarbon exploration. In the absence of national regulation, Shell follows its HSSE & SP Control Framework specification for the discharge of drilling fluids and cuttings, which includes: Discharge of cuttings via a caisson at greater than 15 m water depth; Discharge of cuttings only in water depths greater than 30 m; Treatment of cuttings to reduce the: > Oil content to 6.9% or less of dry cutting weight; > PAH to less than 0.001; > Hg to less than 1 mg/kg; and > Cd to less than 3 mg/kg. The drill contractor would also be required to monitor cement returns and cement pumping would be terminated if returns are observed on the seafloor. Performance objectives Protect sensitive seabed habitats. Impact assessment The assessment of potential impacts due to smothering from the discharge of cuttings, drilling fluids and cement are presented in Section to below. Since the deposition footprint of the cuttings fallout is applicable to all impacts, the results of the drill cuttings dispersion study (as described in Section ), which modelled two discharge scenarios representing two different current regimes in September (strong south-westerly flow) and December (strong north-westerly flow), are summarised below. Both simulations predict a circular deposition area of thicknesses 5 mm adjacent to the drill site and an elongated deposition area for the very fine sediment (0.001 mm) that extends up to 7 km from the drill site. Although both scenarios have a similar deposition area ranging from 17 km 2 (December) to 20 km 2 (September), the direction of particle transport and shape of the deposition areas differ. During September, the deposition area elongates to the south/south-east, while during December the deposition area extends to the north/north-west due to different predominant currents throughout the water column. The maximum predicted cumulative deposition thicknesses immediately adjacent to the wellhead were 68 mm and 71 mm for the September and December discharge scenarios, respectively. Thicknesses 1 mm extend 125 m from the wellhead, thicknesses > 10 mm extend up to 60 m, and thickness > 50 mm are confined to an area within 25 m from the drill site Smothering by cuttings, drilling fluid and cement The primary impact of discharged cuttings, drilling fluid (or mud) and cement is smothering of relatively immobile or sedentary benthic species both directly (e.g. mortality and clogging of feeding mechanisms) and indirectly (e.g. loss of benthic prey items for bottom feeding species, disturbance of migration routes and impact on those species that spawn on the seabed or have a benthic juvenile development stage). The effects of smothering on the receiving benthic macrofauna are determined by (1) the depth of burial; (2) the tolerance of species (life habitats, escape potential, tolerance to hypoxia, etc.); (3) the nature of the depositing sediments; and (4) duration of burial.

14 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-14 The cuttings discharged at the seabed during the spudding of a well would form a highly localised spoil mound around the wellbore, thinning outwards (see Figure 6-1). As noted above, the drill cuttings dispersion study predicts that the cuttings deposition thickness ranges from 71 mm (maximum) adjacent to the wellhead to a thickness of 1 mm at a distance of 125 m from the wellhead. Excess cement would also accumulate adjacent to the wellbore. In contrast, the cuttings discharged from the drilling unit form two plumes as they are discharged. The heavier cuttings and flocculated clay/barite particles (>0.2 mm), which constitute approximately 70% of the discharge, settle to the seabed near the wellbore while the fine-grained unflocculated solids and dissolved components of the mud (30% of the discharge) are dispersed in the water column at increasing distances from the drilling unit. The results of the drill cuttings dispersion study predict an elongated deposition area for the very fine sediment (0.001 mm) extending up to 7 km from the drill site. Figure 6-1: Hypothetical dispersion and fates of cuttings following discharge to the ocean (Adapted from Neff 2005) In areas where sedimentation is naturally high (e.g. wave-disturbed shallow waters) the ability of taxa to migrate through layers of deposited sediment is likely to be well developed. However, sedentary and relatively immobile species that occur in waters beyond the influence of aeolian and riverine inputs, such as the area of interest, would be more susceptible to smothering. However, deep water fauna inhabiting unconsolidated sediments usually comprising fast-growing species that are able to rapidly recruit into disturbed areas. In contrast, the benthos associated with hard substrata (e.g. Tripp Seamount) is typically vulnerable to disturbance due to their long generation times. Tripp Seamount is located approximately 50 km south-east of the area of interest at its closest point and thus outside the predicted cuttings deposition footprint. Although the deposition area elongates to the south/south-east towards Tripp Seamount during the September simulation, it still falls 43 km short of this sensitive receptor. Thus, when considering the impact on vulnerable habitats, the time of year for drilling is not an important variable.

15 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-15 Benthic and demersal species that spawn, lay eggs or have juvenile life stages dependent on the seafloor habitat (e.g. hake) may be negatively affected by smothering effects. Due to the offshore location of the area of interest, plankton abundance is expected to be low, with the major fish spawning and migration routes occurring further inshore on the shelf (see Figure 5-7). Although there is considerable variability in species response to specific sediment characteristics, higher mortalities have been recorded when the deposited sediments have a different grain-size composition from that of the receiving environment, which would be the case in the discharge of drill cuttings. Migration ability and survival rates of organisms are generally lower in silty sediments than in coarser sediments. Provided the sedimentation rate of incidental deposition is not higher than the velocity at which the organisms can move or grow upwards, such deposition may not have negative effects. Studies have found that changes in abundance and diversity of macrofaunal communities in response to deposited cuttings are typically detected within a few 100 m of the discharge (Neff et al., 1992; Ranger, 1993; Montagna and Harper, 1996; Schaanning et al., 2008), with recovery of the benthos observed to take from several months to several years after drilling operations had ceased (Husky, 2000, 2001a, 2001b; Buchanan et al., 2003; Neff, 2005; Currie & Isaacs, 2005). Substantial recovery is, however, expected within a year. Many benthic infaunal species are able to burrow or move through the sediment matrix, and some infaunal species are able to actively migrate vertically through overlying deposited sediment thereby significantly affecting the recolonisation and subsequent recovery of impacted areas. Due to the high natural variability of benthic communities in the region, the structure of the recovering communities would likely be highly spatially and temporally variable. In addition, short-term physical disturbance resulting from exploration drilling would be no more stressful than the regular naturally occurring anoxic events typical of the West Coast continental shelf areas. The smothering effects resulting from the discharge of drilling solids at the wellbore would have an impact of medium intensity on the benthic macrofauna of unconsolidated sediments in the cuttings footprint, whereas discharges from the drilling unit would have a low intensity impact. In both cases, the impact is localised (up to 7 km from the drill site, covering between 17 km 2 to 20 km 2 ) and recovery is expected within a few years (2 to 5 years). The impact is thus considered to be of very low significance for discharges at the wellbore and insignificant for discharges from the drilling unit without mitigation regardless of the time of year the well is drilled. However, should the cuttings footprint overlap with vulnerable communities on hard substrates, the smothering effects could potentially have an impact of high intensity, and recovery would only be expected over the medium- to long-term due to their long generation times. This impact is considered to be of low to medium significance before mitigation. A summary of possible impacts related to smothering from cuttings, drilling fluid and cement are provided in Tables 6-4 and 6-5. Mitigation The following measures would be implemented to reduce and manage the potential smothering impacts: No. Mitigation measure Classification 1 Review ROV footage of pre-drilling surveys to identify potential vulnerable habitats within 500 m of the drill site. 2 Ensure drill site is located more than 500 m from any identified vulnerable habitats. 3 Avoiding excess cement usage by monitoring (by ROV) for discharges during cementing. Avoid/reduce at source Avoid/reduce at source Avoid/reduce at source

16 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-16 Residual impact This potential impact cannot be eliminated due to the need for and nature of the drilling discharges. With the implementation of the project controls and mitigation measures and avoidance of vulnerable habitats within 500 m of the drill site, the impacts range from INSIGNIFICANT (drilling unit discharge) to VERY LOW (wellbore discharge). Monitoring Shell to monitor (using ROV) cement returns and terminate pumping when returns are observed on the seafloor. Table 6-4: Impact on benthic communities (unconsolidated sediments) as a result of smothering from the discharge of cuttings, drilling fluids and cement CRITERIA WITHOUT MITIGATION WITH MITIGATION Discharge from wellbore Extent Local Local Duration Short-term Short-term Intensity Medium Medium Probability Probable Probable Confidence High High Significance Very Low VERY LOW Discharge from drilling unit Extent Local Local Duration Short-term Short-term Intensity Low Low Probability Possible Possible Confidence High High Significance Insignificant INSIGNIFICANT Reversibility Mitigation potential Fully reversible None Table 6-4: Impact on benthic communities (hard substrates) as a result of smothering from the discharge of cuttings from the drilling unit CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Medium- to Long-term Short-term Intensity High Medium Probability Improbable Improbable Confidence Medium Medium Significance Low to Medium INSIGNIFICANT Reversibility Mitigation potential Partially reversible Medium

17 SLR Environmental Consulting (Namibia) (Pty) Ltd Page Toxicity and bioaccumulation effects on marine fauna The primary effects related to the discharge of WBM (during riserless drilling) and residual SBM (during risered drilling) include direct toxicity and bioaccumulation. The effects may be of significance in terms of: Chronic accumulation of persistent contaminants in the marine environment; Acute or chronic effects on biota, including effects on productivity; and Acute or chronic effects on other biota (i.e. indirect effects on biodiversity). Drilling fluids Two types of drilling fluid would be used during drilling. During the initial riserless drilling stage WBM would be used. During the risered drilling stage, a low toxicity SBM would be used, when WBM cannot provide the necessary characteristics. Approximately m 3 of WBM and 10 m 3 of residual SBM would be discharged to the sea. The disposal of mud into the marine environment and its subsequent effect has been extensively investigated through field and laboratory studies. Several metals typically occur in significantly higher concentrations in drilling muds than in uncontaminated marine sediments. However, most of these are not bioavailable to benthic fauna and thus do not bioaccumulate in the marine food chain. Toxicity testing of WBM and SBM has indicated that they constitute a low risk of chemical toxicity to marine communities. The two most abundant ingredients in WBM, barite and bentonite, are insoluble and non-biodegradable. Other additives such as gluteraldehyde, inorganic salts and lignosulfonate thinners are only mildly toxic to marine life, but are present in such low concentrations that evidence of long-lasting ecological impacts are lacking. The additives include low toxicity mineral oil, corrosion inhibitors, detergents, defoamers, and emulsion breakers, but are usually not present in concentrations high enough to contribute significantly to whole mud toxicity. Thus, the toxicity effects of WBM are negligible. Similarly, the potential for significant bioaccumulation of SBM in the marine environment is unlikely due to their extremely low water solubility and consequent low bioavailability. Due to the high dilution and wide dispersal of the dissolved and particulate components of SBM, the biological effects associated with their use typically do not extend beyond m from the drilling unit (Husky 2000, 2001; Buchanan et al. 2003; OGP 2003), with complete recovery of impacted communities being predicted within 3-5 years. The vulnerable benthic communities associated with Tripp Seamount are not expected to be affected by toxicity and bioaccumulation effects related to drilling fluids, as it is far removed from the deposition footprint. Assuming that the WBM to be used in drilling the initial section of the well do not contain spotting fluids or lubricating hydrocarbons, the impacts of discharges of these drilling fluids to both the water column and the sediments are considered of low intensity and of short-term duration (2 5 years). As the area affected by discharged drilling fluids would be highly localised adjacent to the wellhead, any potential adverse effects of WBM on sessile benthos would be of very low significance before mitigation. In the case of residual SBM on the cuttings, the impacts of discharged muds are considered of medium intensity and of short-term duration (3 5 years). However, as the area affected by discharged drilling fluids would be localised (up to 7 km from the drill site, covering between 17 km 2 to 20 km 2 ) and of very thin deposition thickness, any potential adverse effects on sessile benthos or on the feeding, spawning and recruitment of mobile predators, are also considered to be of very low significance before mitigation. Cement Typically, cement and cement additives are not discharged from drilling units. However, during the initial cementing operation, excess cement emerges out of the top of the well and onto the seafloor in order to ensure the conductor pipe is cemented all the way to the seafloor. In the worst-case scenario approximately 200 m 3 of cement could be discharged onto the seafloor. If cement returns are observed on the seafloor pumping would be terminated.

18 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-18 Various chemical additives are also used in the cementing programme to control its properties, including setting retarders and accelerators, surfactants, stabilisers and defoamers. The formulations are adapted to meet the requirements of a particular well. Their concentrations typically make up <10 % of the overall cement used. The additives have a low toxicity to marine life (Ranger 1993; Chevron 1994) and the organic additives are partially biodegradable. The indirect impact of leaching of cement additives into the surrounding water column and their potential toxic effects on benthic communities or the potential for bioaccumulation is of low intensity and extremely localised (i.e. confined to the wellbore footprint) and would likely persist only over the short-term. As physiological effects would be fully reversible, the biochemical impacts can thus be rated as being of very low significance without mitigation. A summary of possible impacts related to the toxicity and bioaccumulation effects of drilling fluid and cement are provided in Tables 6-6 to 6-8. Mitigation In addition to Shell s HSSE & SP Control Framework specifications (including discharge standards and depth of discharge) and the measures recommended to avoid of vulnerable habitats (see Section ), the following measures would be implemented to reduce the toxicity and bioaccumulation effects on marine fauna: No. Mitigation measure Classification 1 Ensure only low-toxicity and partially biodegradable additives are used in drilling fluid and cement. 2 Use high efficiency solids control equipment to reduce the need for fluid change out and minimise the amount of residual fluid on drilled cuttings. Avoid/reduce at source Avoid/reduce at source 3 Ensure regular maintenance of the onboard solids control package. Reduce at source/abate on site 4 Ensure all recovered SBM is taken to shore for treatment and reuse. Avoid/Abate on and off site Residual impact This potential impact cannot be eliminated due to the nature of the drilling approach and the necessity for the use of WBM and SBM in the drilling process. With the implementation of project controls and mitigation measures, the residual impact on marine fauna would have a lower intensity and probability, and the level would drop to INSIGNIFICANT for the effects of WBM and cement, but remain at VERY LOW significance for residual SBM. Monitoring Shell to test drilling fluids for toxicity, barite contamination and oil content to ensure the specified discharge standards are maintained.

19 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-19 Table 6-6: Impact of WBM on marine organisms due to toxicity and bioaccumulation effects CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Low Low Probability Probable Possible Confidence Medium Medium Significance Very Low INSIGNIFICANT Reversibility Mitigation potential Fully reversible Low Table 6-7: Impact of residual SBM on marine organisms due to toxicity and bioaccumulation effects CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Medium Low Probability Probable Probable Confidence Medium Medium Significance Very Low Very Low Reversibility Mitigation potential Partially reversible Very Low Table 6-8: Impact of cement on marine organisms due to toxicity and bioaccumulation effects CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Low Very Low Probability Probable Possible Confidence Medium Medium Significance Very Low INSIGNIFICANT Reversibility Mitigation potential Fully reversible Low Increased water turbidity and reduced light penetration The discharge of cuttings would result in changes in water turbidity in the vicinity of the discharge point, which could reduce light penetration through the water column with potential adverse effects on the photosynthetic capability of phytoplankton and the foraging efficiency of visual predators. Turbid water is a natural occurrence along the southern African west coast, resulting from aeolian and riverine inputs, re-suspension of seabed sediments in the wave-influenced nearshore areas and seasonal phytoplankton production in the upwelling zones. However, further offshore in the proposed area of interest, surface waters tend to be clearer and less productive as they are beyond the influence of coastal upwelling (see Figure 5-4). Consequently, the major spawning areas are all located on the continental shelf well

20 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-20 inshore of the proposed area of interest (see Figure 5-7). Any potential effects of turbid water plumes generated during cutting disposal on phytoplankton and ichthyoplankton production, fish migration routes and spawning areas would thus be negligible. Increased turbidity of near-bottom waters through disposal of cuttings at the wellbore and sea surface may place transient stress on sessile and mobile benthic organisms, by negatively affecting filter-feeding efficiency of suspension feeders or through disorientation due to reduced visibility. However, in most cases sub-lethal or lethal responses occur only at concentrations well in excess of those anticipated at the wellbore. Furthermore, as marine communities in the Benguela are frequently exposed to naturally elevated suspended-sediment levels, they can be expected to have behavioural and physiological mechanisms for coping with this feature of their habitat. The impact of increased turbidity in the water column and elevated suspended sediment concentrations would thus be comparatively localised (up to 7 km from the drill site, covering between 17 km 2 to 20 km 2 ), of low intensity over the very short term (days), and is considered to be of insignificant without mitigation (see Table 6-9). Mitigation No mitigation measures for potential indirect impacts on the water column are proposed or deemed necessary. Residual impact This potential impact cannot be eliminated due to the necessity of disposal of drill cuttings and thus remains INSIGNIFICANT. Table 6-9: Impacts of drill cuttings discharge on water column and bottom-water biochemistry (turbidity and light) CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Duration Intensity Probability Confidence Significance Local Short-term Low Possible Medium Insignificant No mitigation is considered necessary Reversibility Mitigation potential Fully reversible Low Reduced physiological functioning of marine organisms due to indirect biochemical effects A further indirect impact (arising indirectly from biochemical effects on the sediments) associated with cuttings disposal is the potential development of hypoxic conditions in the near-surface sediment layers through bacterial decomposition of organic matter. The release of particulate organic matter into the water column can result in local organic enrichment and consequent oxygen depletion through decomposition, thereby changing the chemical properties of the near-surface sediment layers by generating potentially toxic concentrations of sulfide and ammonia. Oxygen depletion in the sediments around a well site may also develop in response to organic enrichment following fall-out of fouling organisms off submerged drilling unit structures.

21 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-21 Organically enriched sediments (often hypoxic or anoxic) harbour markedly different benthic communities to oxygenated sediments. WBM cuttings typically contain low concentrations of biodegradable organic matter and do not support large populations of bacteria. However, SBM typically degrade rapidly and can cause localised hypoxia in underlying sediments. Marine organisms respond to hypoxia in various different ways which can result in reduced growth and feeding, and may eventually affect individual fitness. More mobile species would be able to actively avoid hypoxia, although this may render them more vulnerable to predation. However, hypoxia may eliminate relatively immobile or sedentary benthic species, thereby changing the species composition of the community. The bulk of the seawater in the study area comprises South Atlantic Central Water, which has depressed oxygen concentrations (approximately 80% saturation value), with lower oxygen concentrations (<40% saturation) occurring frequently due to nutrient remineralisation in bottom waters. Benthic communities in the study area will, therefore, most likely be adapted to low oxygen conditions and will be characterised either by species able to survive chronic hypoxia, or colonising and fast-growing species able to rapidly recruit into areas that have suffered oxygen depletion. Development of anoxic conditions beneath deposited cuttings is unlikely due to the low deposition thicknesses (<1 mm) predicted in the cuttings fallout footprint for distances beyond approximately 130 m from the well location. Should anoxic conditions develop, these are likely to be limited to within the 0.03 km 2 footprint of the WBM depositional area, where they would have an impact of medium intensity on the benthic macrofauna, with recovery expected within a few months. The impact is thus considered to be of insignificant significance without mitigation (see Table 6-10). Mitigation No mitigation measures for potential indirect impacts on the water column are proposed or deemed necessary. Residual impact This potential impact cannot be eliminated due to the necessity of disposal of drill cuttings and thus remains of INSIGNIFICANT. Table 6-10: Impact on benthic communities due to biochemical effects related to the development of anoxic sediments CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Duration Intensity Probability Confidence Significance Local Short-term Low Possible Medium Insignificant No mitigation is considered necessary Reversibility Mitigation potential Fully reversible None

22 SLR Environmental Consulting (Namibia) (Pty) Ltd Page PHYSICAL DISTURBANCE OF THE SEABED SEDIMENTS Description of the source of impact The table below summarises the project activities that are likely to disturb seabed sediments. Project phase Mobilisation Operation Demobilisation Activity n/a Pre-drilling ROV seabed survey Drilling and spudding of the exploration well Installation of the wellhead and BOP Removal of BOP n/a These activities are described further below: During pre-drilling surveys, a ROV would be deployed to obtain video footage of the seabed at the proposed well location. Although the standard operating procedure is not to settle or rest the ROV on the seabed, the ROVs thrusters may stir up the soft or silty sediments when operating close to the seabed. This resuspension of fine sediments would temporarily disturb seabed communities and result in localised increased turbidity. The current well design parameter is to have a wellbore diameter of 36 inch (91 cm) during spudding. The penetration of the seabed by the drill bit would physically disturb a surface area of m 2, and displace deeper sediments into a conical cuttings pile around the wellhead. Casing of the hole and installation of the wellhead and BOP would potentially also result in localised direct disturbance of an area of about 3 m 2 around the well site. The removal of the BOP, which would include the use of a ROV, may also result in the localised disturbance of the seabed. Description of the environmental aspects Drilling operations would result in the direct physical disturbance and removal of sediments, as well as potential changes in sediment characteristics and condition. Description of the potential impact Any benthic fauna present on the seabed and in the sediment in the disturbance footprint would be either completely eliminated or may potentially be disturbed or crushed. Resuspension of seabed sediments by ROV thrusters may also result in increased turbidity near the seabed, potentially with physiological effects on benthic faunal communities. Receptors Section notes that deep water fauna inhabiting unconsolidated sediments, as expected in the area of interest, is expected to be relatively ubiquitous, usually comprising fast-growing species able to rapidly recruit into areas that have suffered disturbance. In contrast, the benthos associated with hard substrata is typically vulnerable to disturbance due to their long generation times. Such sensitive communities would only be expected to occur at Tripp Seamount and in the adjacent submarine canyon, which are located approximately 50 km south-east of the area of interest at its closest point. Project Controls and Industry Practice Shell has no project controls specifically governing the disturbance of seabed habitats during hydrocarbon exploration. However, it is the intention of Shell to ensure that the proposed drilling operation is undertaken in a manner consistent with good international industry practice.

23 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-23 Performance objectives Protect sensitive seabed habitats. Impact assessment Assuming an initial drill diameter of 36 inches (91 cm) during spudding, penetration of the seabed by the drill bit would disturb a surface area of approximately 0.65 m 2 per well and any benthic fauna present on the seabed and in the top 20 to 30 cm of sediment would be impacted. The installation of the wellhead (approximately 3 m 2 ) is also likely to result in localised disturbance of macrofauna in the immediate vicinity of the well site. Further loss or disturbance of the benthos due to smothering by disposal of drilling muds and cuttings is discussed further in Section Since anchoring in the area of interest is not practical due to the water depths, there would be no additional disturbance from anchoring. The immediate effect on the benthos depends on their degree of mobility, with sedentary and relatively immobile species likely to be physically damaged or destroyed during the drilling disturbance. Sediment in the area of interest is dominated by muds and sandy muds (see Figure 5-1). Due to the high natural variability in benthic communities in the region, the structure of the communities in the area of interest would likely be highly spatially and temporally variable, and is likely to comprise fast-growing species able to rapidly recruit into areas that have suffered natural environmental disturbance. Hard substrates in an area of otherwise unconsolidated sediments would be minimised, as the preference would be to have a level surface area to facilitate spudding and installation of the wellhead. Vulnerable habitats on Tripp Seamount would not be affected. Considering the available area of similar habitat on and off the edge of the continental shelf in the Atlantic Offshore Bioregion, this minimal disturbance of and reduction in benthic biodiversity can be considered negligible, with no cascade effects on higher order consumers expected. Impacts on the offshore benthos as a result of physical damage and sediment disturbance are considered to be very localised. The intensity and duration of an impact on unconsolidated sediments is considered to be of medium intensity in the short-term (recovery is expected to take place within two to five years). Therefore, this impact on unconsolidated sediments is assessed to be of very low significance without mitigation (see Table 6-11). Mitigation The following measures would be implemented to reduce and manage the disturbance to sediments through drilling: No. Mitigation measure Classification 1 Review ROV footage of pre-drilling surveys to identify potential vulnerable habitats within 500 m of the drill site 2 Ensure drill site is located more than 500 m from any identified vulnerable habitats Avoid/reduce at source Avoid/reduce at source Residual impact This potential impact cannot be eliminated due to the nature of drilling. With the implementation of the project controls and mitigation measures, the residual impact remains of VERY LOW significance.

24 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-24 Table 6-11: Impacts on benthic macrofauna of unconsolidated sediments through removal or crushing CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Medium Low Probability Definite Probable Confidence High High Significance Very Low VERY LOW Reversibility Mitigation potential Fully reversible Very Low DRILLING NOISE Description of the source of impact The table below summarises the project activities would increase the ambient noise levels. Project phase Mobilisation Operation Demobilisation Activity Transit of drilling units and support vessels to the drill site Operation of drilling unit and support vessels Operation of helicopters Vertical seismic profiling of the well Flaring during well testing (optional for appraisal well only) Drilling unit/support vessels leave drill site and transit to port or next destination These activities are described further below: Drilling noise: Drilling vessels generally produce low-frequency underwater noise in the range of 10 Hz to 10 khz (OSPAR commission, 2009) with major frequency components below 100 Hz and average source levels of db re 1 µpa at 1 m (rms). Underwater noise monitoring conducted for another dynamically positioned drill-ship, operating offshore Greenland, reported elevated noise levels in the range from 100 Hz to beyond 10 khz at close range (0.5 km), decreasing to about 4 khz at distances between 2 km and 8 km. The estimated source level during drilling was 184 db re 1 µpa (Kyhn et al., 2011). During maintenance, levels were elevated from 20 Hz to well above 10 khz at all distances up to and including 38 km from the drill-ship with an estimated source level of 190 db re 1 µpa (OSPAR commission, 2009). These noise levels will be assumed as indicative for the Noble Globetrotter II. Propeller and positioning thrusters: Noise from propellers and thrusters is predominately caused by cavitation around the blades whilst transiting at speed or operating thrusters under load in order to maintain a vessel s position. The noise produced by drilling vessels dynamic positioning systems can be audible for many kilometres. Noise produced is typically broadband noise, with some low tonal peaks. In the Greenland study (Kyhn et al., 2011), the drill-ship s positioning system generated signals audible between 20 khz and 35 khz up to 2 km from the drilling vessel. These noise levels will be assumed as indicative for the Noble Globetrotter II. Well logging noise: Vertical seismic profiling (VSP) is a standard method used during well logging and can generate noise that could exceed ambient noise levels. VSP source generates a pulse noise level around 190 db re 1µPa at 1m in the 5 to 100 Hz range and decreases rapidly with distance from the source. VSP uses a small airgun array; volumes and the energy released into the marine environment are significantly smaller than what is required or generated during conventional seismic surveys. The

25 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-25 airgun array would be discharged approximately five times at 20 second intervals. This process is repeated, as required, for different sections of the well. A VSP is expected to take approximately 8 to 10 hours per well to complete, depending on the well s depth and number of stations being profiled. Well testing noise: Flaring during well testing would generate noise from the burner and associated pipework and separation equipment. Noise generation would be largely dependent on the flow rate during the test. Well testing is expected to last approximately 48 hours with clean-up and main flow (and highest noise emissions) accounting for approximately 36 hours within this period. Machinery noise: Machinery noise is often of low frequency and can become dominant for vessels when stationary or moving at low speeds. The nature of sound is dependent on a number of variables, such as the type and size of machinery operating; and the coupling between machinery and the vessel body. Equipment in water: Noise is produced from equipment such as the drill string. The noise produced would be low relative to the drilling noise and the dynamic positioning system. An ROV would be used to conduct a sweep of the drilling site to identify any debris; however, this is not expected to form a significant noise source. Helicopter noise: Helicopters would also form a source of noise, which can affect marine fauna both in terms of underwater noise beneath the helicopter and airborne noise. Crew transfers by helicopter would occur between the Lüderitz airport and the drilling unit. Description of the environmental aspects Project activities would increase the ambient noise levels in the vicinity of the drill site and on route to Lüderitz. Description of the potential impact Elevated noise levels could impact marine fauna by: causing direct physical injury to hearing or other organs; masking or interfering with other biologically important sounds (e.g. communication, echolocation, signals and sounds produced by predators or prey); and causing disturbance to the receptor resulting in behavioural changes or displacement from important feeding or breeding areas. Receptors The drilling activities would be located in the offshore marine environment, more than 200 km offshore, far removed from the NIMPA, coastal islands and any sensitive coastal receptors (e.g. key faunal breeding/feeding areas, bird or seal colonies and nursery areas for commercial fish stocks), and levelled noise levels at the drill site are not expected to reach these shore receptors. However, support vessels and helicopters operating between Lüderitz and the drilling unit would be required to travel through the NIMPA and sensitive coastal area. Underwater noise generated during the project could affect a wide range of fauna; from benthic invertebrates and demersal species residing on the seabed in the vicinity of the wellhead, to those invertebrates and vertebrates occurring throughout the water column and in the pelagic habitat near the surface. In the offshore environment, the taxa most vulnerable to spills are pelagic seabirds, although turtles, large migratory pelagic fish and cetaceans may also be affected. Many of these are considered globally Critically Endangered (e.g. leatherback turtle), Endangered (e.g. black-browed and yellow-nosed albatross, fin, blue and sei whales) Vulnerable (e.g. short-fin mako shark, whitetip shark and sperm whale) or Near threatened (e.g. blue shark).

26 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-26 Noise generated by helicopters undertaking crew transfers between Lüderitz and the drill unit could affect seabirds and seals in breeding colonies and roosts on the mainland coast and on the offshore islands of the NIMPA. Many of the seabirds roosting and nesting on the islands are listed as Endangered (e.g. African Penguin, Bank Cormorant, Cape Gannet), Near Threatened (e.g. Cape Cormorant, Crowned Cormorant, Damara Tern) or Vulnerable (e.g. Hartlaub s Gull, Swift Tern) on the Namibian IUCN Red Data Book. Low altitude flights over the ocean could also affect marine mammals and turtles in surface waters, both within the NIMPA and offshore thereof. Project Controls and Industry Practice Although Shell does not have standard project controls regarding noise emissions during well drilling, Shell has reduced the size of the initial area of interest in order to avoid/reduce the potential impact on marine fauna associated with Tripp Seamount. Initially the area of interest was much larger and was located within 15 km of Tripp Seamount (see Figure 4-31). The revised area of interest considered in this EIA is located approximately 50 km south-east of Tripp Seamount at its closest point. Performance objectives Protect offshore marine fauna Impact assessment The assessment of potential impacts due to increased ambient noise levels are presented in Sections to below Noise from drilling operations The ocean is a naturally noisy place and marine animals are continually subjected to sounds from physical sources such as wind, rainfall, breaking waves and natural seismic noise, or biologically produced sounds generated during reproductive displays, territorial defence, feeding, or in echolocation. Such acoustic cues are thought to be important to many marine animals in the perception of their environment as well as for navigation purposes, predator avoidance, and in mediating social and reproductive behaviour. Anthropogenic sound sources in the ocean can be expected to interfere directly or indirectly with such activities affecting the physiology and behaviour of marine organisms (NRC, 2003). Of all human-generated sound sources, the most persistent in the ocean is the noise of shipping. Figure 6-2 provides an overview of the noise levels produced by various natural and anthropogenic sources, relative to typical background or ambient noise levels in the ocean. Unlike the noise generated by airguns during seismic surveys, underwater noise from drilling operations is not considered to be of sufficient amplitude to cause direct harm to marine life, even at close range. However, the drilling operations may induce localised behavioural changes or masking of biologically relevant sounds in some marine fauna. Research has found that the responses of cetaceans to noise sources are often dependent on the perceived motion of the sound source, as well as the nature of the sound itself. For example, many whales are more likely to tolerate a stationary source than they are one that is approaching them (Watkins, 1986; Leung-Ng & Leung, 2003) or are more likely to respond to a stimulus with a sudden onset than to one that is continuously present (Malme et al., 1985).

27 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-27 Figure 6-2: Comparison of noise sources in the ocean (Source: Wenz, 1962) The noise assessment undertaken as part of this EIA (see Appendix 4.2) estimated the underwater ambient noise levels in the area of interest to range from about 80 db re 1 µpa in calm conditions (including possible low frequency noise component) up to about 120 db re 1 µpa during periods of higher winds and or heavy rainfall, or when ships are moving past the drill site. Table 4-11 provides the distances at which noise from various drilling operations might be detectable above the ambient noise level in the project area, using a median noise level of 100 db re 1µPa. In summary, the noise assessment concluded the following: The extent of noise impacts above the background noise level may vary considerably depending on the specific vessels used and the number of support vessels operating. It would also depend on the variation in the background noise level with weather and with the proximity of other vessel traffic (not associated with the project). Noise from project activities is expected to decrease to below the estimated median ambient background level of 100 db re 1µPa within a distance of approximately 32 km from the drill site in all cases, with maintenance and VSP activities representing the worst-case scenario for noise. However, this scenario would be expected to occur only for relatively short periods of time. Noise from project activities is expected to decrease to below the estimated upper boundary of ambient background level of 120 db within a distance of less than 5 km from the drill site in all cases. Since the minimum distance between the area of interest and the Tripp Seamount is approximately 50 km at its closest point, received noise levels from the drilling activities at the seamount are predicted to be within the typical range of existing ambient noise levels. Adverse underwater noise impacts at the Tripp Seamount are, therefore, considered unlikely. The impact of underwater noise on marine fauna generated during drilling and by project vessels is considered to be of low intensity in the drilling area (32 km from drill site) and for the duration of the drilling campaign (two months). Underwater noise may mask biologically significant sounds and disturbance and behavioural changes are possible. In both cases impacts are fully reversible once drilling operations are completed. The impact of underwater noise potentially masking biologically significant sounds is considered of very low significance without mitigation, whereas the impact of underwater noise resulting in avoidance of

28 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-28 feeding and/or breeding area is considered insignificant without mitigation due to the extreme offshore location of the area of interest and its distance from Tripp Seamount. During VSP, which may be undertaken, the noise effects on marine fauna are considered to be of medium intensity but restricted to the area of interest (32 km from drill site) and for the duration of the VSP activities (8 to 10 hours). Noise generated by VSP may mask biologically significant sounds and cause disturbance and behavioural changes in the receptors, but impacts are fully reversible once VSP operations are completed. The impact of underwater noise generated during VSP is thus considered of very low significance without mitigation. A summary of likely impacts related to elevated underwater noise levels are provided in Tables 6-12 to Mitigation The following measures would be implemented: No. Mitigation measure Classification 1 VSP operations: 1.1 Assign relevant staff for observation, distance estimation and reporting, to perform marine mammal observations and notifications. 1.2 Undertake a 30-minute pre-start scan (prior to soft-starts) within the 3 km radius observation zone in order to confirm there is no cetacean activity within 500 m of the source. 1.3 Implement a soft-start procedure of a minimum of 20 minutes duration when initiating the VSP acoustic source. This requires that the sound source be ramped from low to full power rather than initiated at full power, thus allowing a flight response by marine fauna to outside the zone of injury or avoidance. 1.4 Commence soft-start procedure only once it has been confirmed by a suitably trained crew member during the 30-minute pre start-up visual scan that there is no cetacean activity within 500 m of the source. 1.5 Maintain visual observations within the 500 m shut-down zone continuously during VSP operation to identify if there are any cetaceans present. 1.6 Shut down the acoustic source if a cetacean is sighted within 500 m shut-down zone until such time as the animal has moved to a point more than 500 m from the source. 1.7 Ensure that during periods of low visibility (where the observation zone cannot be clearly viewed out to 3 km), including night-time, the VSP source is only used if during the preceding 24-hour period: there have not been three or more cetacean-instigated shut down situations, and a two-hour period of continual observation was undertaken in good visibility (to the extent of the observation zone) and no cetaceans were sighted. Abate on site Abate on site Abate on site Abate on site Abate on site Abate on site Abate on site Residual impact The generation of noise from drilling operations cannot be eliminated. However, with the implementation of the project controls and mitigation measures specifically for VSP, the residual impact on marine fauna would have a lower intensity and probability, and the level would reduce to INSIGNIFICANT. The residual impact on behavioural changes/masking and avoidance as a result of drilling and project vessels would remain of VERY LOW and INSIGNIFICANT, respectively.

29 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-29 Table 6-12: Impact of underwater noise on marine fauna generated during drilling and by project vessels CRITERIA WITHOUT MITIGATION WITH MITIGATION Behavioural changes and masking of biologically significant sounds Extent Duration Intensity Probability Confidence Significance Avoidance of feeding and/or breeding areas Extent Duration Intensity Probability Confidence Significance Local Short-term Low Probable High Very Low Local Short-term Low Improbable High Insignificant No mitigation is considered necessary No mitigation is considered necessary Reversibility Mitigation potential Fully reversible None Table 6-13: Impact of underwater noise on marine fauna generated during VSP operations CRITERIA WITHOUT MITIGATION WITH MITIGATION Behavioural changes and masking of biologically significant sounds Extent Local Local Duration Short-term Short-term Intensity Medium Low Probability Probable Possible Confidence High High Significance Very Low INSIGNIFICANT Reversibility Mitigation potential Fully reversible Low Noise from helicopter operations Transportation of personnel to and from the drilling unit would be provided by helicopter operations from the airport outside Lüderitz. Helicopters flying between the drilling unit and airport may fly over sensitive receptors, such as bird and seal colonies or breeding/calving cetaceans. The noise generated by the helicopters may temporarily disturb marine fauna, which may result in the abandonment of nests or young, injury to individuals or impact breeding activities. The direct flight path from the Lüderitz airport to the area of interest would pass over the NIMPA and just south of Wolf Bay, Atlas Bay and Long Islands (see Figure 6-3), which together represent the largest breeding concentration of seals in Namibia. These islands also provide a vital breeding habitat for seabirds, some of which are threatened (e.g. African penguin, bank cormorants, crowned cormorants, oystercatchers and gannets).

30 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-30 Low altitude flights over bird breeding colonies could result in temporary abandonment of nests and exposure of eggs and chicks leading to increased predation risk. The nearest islands to a direct flight path to the area of interest are Ladies Rock and Long Island, approximately 1 km south and 2 km north of the flight path, respectively (see Figure 6-3). Figure 6.3: A direct flight path (red line) from the Lüderitz airport to the area of interest in relation to sensitive coastal receptors (Adapted from GoogleEarth) Seals may also experience severe disturbance from aircrafts usually reacting by showing a startle response and moving rapidly into the water. Although any observed response is usually short-lived, disturbance of breeding seals can lead to pup mortalities through abandonment or injury by fleeing, frightened adults. The closest seal colonies are at Atlas Bay and Long Island, approximately 1 and 2 km north of a direct flight path, respectively (see Figure 6-3). Low altitude flights (especially near the coast) can also have a significant disturbance impact on cetaceans during their breeding and mating season. Southern right whales were completely displaced from Namibian waters during historical whaling activities and have only recently returned to the Namibian coast to calve. Calving and nursing activities are known to occur in Elizabeth Bay (approximately 8 km south-east of a direct flight path) and Hottentot Bay (approximately 60 km north of Lüderitz, well to the north of a direct flight path) (Currie et al., 2009). The months of main calving and nursing activities include June to September. The level of disturbance would also depend on the distance and altitude of the aircraft from the animals (particularly the angle of incidence to the water surface) and the prevailing sea conditions.

31 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-31 Although exposure would be limited up to two flights daily and be of a temporary nature while the helicopter passes overhead, indiscriminate or direct flying over seabird and seal colonies or breeding cetaceans could have a significant disturbance impact on behaviour and breeding success. Although such impacts would be local in the area of the colony, they may have wider ramifications over the range of affected species and are deemed to range from low to high intensity. The significance of impact is considered to be low before mitigation (see Table 6-14). Mitigation The following measures would be implemented: No. Mitigation measure Classification 1 Ensure that all flight paths avoid offshore islands (including Halifax Island, Long Islands, Possession Island and Pomona Island) by at least m (i.e. 1 nm), seal colonies (including Wolf Bay and Atlas Bay) and southern right whale breeding areas (namely Elizabeth Bay during the months of June to September). 2 Maintain an altitude of at least m within the NIMPA and a cruising altitude of greater than 300 m, except when taking off and landing or in a medical emergency. 3 Avoid extensive flights parallel to the coast by ensuring that the flight path is perpendicular to the coast, as far as possible. Avoid/abate on site Avoid/abate on site Avoid/abate on site 4 Comply with aviation and authority guidelines and rules. Avoid/abate on site 5 Brief of all pilots on the ecological risks associated with flying at a low level along the coast or above marine mammals. Avoid/abate on site Residual impact The generation of noise from helicopters cannot be eliminated due to the necessity of crew transfers between the drilling unit and Lüderitz. With the implementation of the project controls and mitigation measures, the residual impact on marine fauna is considered to be INSIGNIFICANT. Table 6-14: Impact of noise from helicopter operations CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Low to High Low Probability Probable Possible Confidence High High Significance Low INSIGNIFICANT Reversibility Mitigation potential Fully reversible Low

32 SLR Environmental Consulting (Namibia) (Pty) Ltd Page VESSEL LIGHTING Description of the source of impact The table below summarises the project activities likely to result in increased ambient lighting. Project phase Mobilisation Operation Demobilisation Activity Transit of drilling units and support vessels to the drill site Operation of drilling unit and support vessels Flaring during production tests (optional for appraisal well only) Drilling unit/support vessels leave drill site and transit to port or next destination These activities are described further below. The operational lighting of drilling unit and support vessels during transit and operation can be a significant source of artificial light in the offshore environment. During well testing it may be necessary to vent or flare off some of the oil and gas brought to the surface. Flaring and venting is also an important safety measure used to ensure gas and other hydrocarbons are safety disposed of in the event of an emergency, power or equipment failure or other plant upset conditions. Flaring and venting produces a flame of intense light at the drill unit. Well testing is expected to last approximately 48 hours with clean-up and main flow accounting for approximately 36 hours within this period. Description of the environmental aspects The strong operational lighting used to illuminate the offshore installations at night or the light from the flaring of gas and oil during a production test would increase ambient lighting in offshore areas. Description of the potential impact Increased ambient lighting may disturb and disorientate pelagic seabirds feeding in the area. Operational lights may also result in physiological and behavioural effects of fish and cephalopods as these maybe drawn to the lights at night where they maybe more easily preyed upon by other fish and seabirds. Receptors The drilling activities would be located in the offshore marine environment, more than 200 km offshore, far removed from any sensitive coastal receptors (e.g. bird or seal colonies), but could still directly affect migratory pelagic species (pelagic seabirds, marine mammals and fish) transiting through the area of interest. Increased ambient lighting would primarily take place at the well location and along the route taken by the support vessels between the drilling unit and Lüderitz. The taxa most vulnerable to ambient lighting pelagic seabirds, although turtles, large migratory pelagic fish and cetaceans. Many of these are considered globally Critically Endangered (e.g. leatherback turtle), Endangered (e.g. black-browed and yellow-nosed albatross, fin, blue and sei whales) Vulnerable (e.g. short-fin mako shark, whitetip shark and sperm whale) or Near threatened (e.g. blue shark). Project Controls and Industry Practice Shell does not have lighting specific project controls. Performance objectives Protect marine fauna, migratory birds and seabirds by managing illumination of the drilling unit and platform supply vessels.

33 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-33 Impact assessment Seabirds, fish, cephalopods (squids), seals, turtles and cetaceans may be attracted to the strong operating lights required during drilling activities and to flaring during any flow testing. Many seabird species forage at night on bioluminescent plankton prey and any light would result in attraction. Potential attraction may increase during fog when greater illumination is caused by refraction of light by moisture droplets. Most seabirds are found relatively close inshore (10-30 km), well outside the area of interest. However, African Penguins and Cape Gannets are known to forage up to 60 km and 140 km offshore, respectively. Most of the pelagic seabird species in the region reach highest densities offshore of the shelf break (200 to 500 m depth), also inshore of the proposed area of interest. However, the lighting may still cause some disturbance or disorientate pelagic seabirds feeding in the area. Although little can be done at the offshore installation to prevent seabird collisions, reports of collisions or death of seabirds on drilling units are rare. It is expected that seabirds and marine mammals in the area would become accustomed to the presence of the installations within a few days, thereby making the significance of the overall impact on these populations negligible. The significance to the populations of fish and squid of increased predation as result of being attracted to an installation s lights is expected to be insignificant. Seals are highly mobile animals with a general foraging area covering the continental shelf up to 120 nm (approximately 220 km) offshore. Since all seal colonies are more than 220 km from the proposed area of interest, numbers can be expected to be low. The extent of impact is likely to be limited to the visual stimulus of the drilling unit and support vessels, while the duration would be short-term (two months). The intensity of impact is likely to range from low (altered distribution and behaviour) to high (mortality) for individuals, the intensity of the impact on the population is expected to be very low. The significance of impact is deemed insignificant without mitigation (see Table 6-15). Mitigation The following measures would be implemented: No. Mitigation measure Classification 1 Reduce the lighting on the drilling unit and support vessels to a minimum compatible with safe operations whenever and wherever possible. 2 Position light sources, if possible and consistent with safe working practices, in places where emissions to the surrounding environment can be minimised. 3 Keep disorientated, but otherwise unharmed, seabirds in dark containers for subsequent release during daylight hours. Avoid/reduce at source Avoid/reduce at source Repair or restore 4 Euthanise of injured birds humanly. Abate at receptor Residual impact The generation of increased ambient lighting cannot be eliminated due to the necessity of navigational and operational lighting on offshore installations and vessels. With the implementation of the project controls and mitigation measures, the residual impact remains INSIGNIFICANT.

34 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-34 Monitoring Personnel with Marine Observer training shall record information on patterns of bird reaction to lights and real incidents of injury/death, including stray land birds resting on the rig, during the drilling operation. Ringed/banded birds should also be reported to the appropriate ringing/banding scheme (details are provided on the ring). Table 6-15: Impacts of increased ambient lighting from drilling units and support vessels CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Local Local Duration Short-term Short-term Intensity Very Low Very Low Probability Possible Possible Confidence High High Significance Insignificant INSIGNIFICANT Reversibility Mitigation potential Fully reversible None PHYSICAL PRESENCE OF SUBSEA INFRASTRUCTURE Description of the source of impact The table below summarises the project activities that are likely to result in increased hard substrata on the seabed. Project phase Mobilisation Operation Demobilisation Activity n/a Placement of wellhead on the seabed Discharge of residual cement during riserless drilling stage Abandonment of wellhead on seabed These activities are described further below: Once the wellhead has been installed a BOP would be lowered to the seabed and installed onto the wellhead. The BOP stack extends approximately 10 m above the seabed into the water column, thereby providing a pillar of hard substrate in an area of otherwise unconsolidated sediments. During initial cementing, excess cement emerges out of the top of the well onto the cuttings pile or is discarded on the seabed, where (depending on its mix) it may set and remain in a pile to subsequently be colonised by epifauna and attract fish and other mobile predators. After the wells have been sealed, tested for integrity and abandoned, the wellhead (with a height of 3 m and a diameter of 1 m) would be left on the seafloor, thereby providing hard substrate in an area of otherwise unconsolidated sediments. Description of the environmental aspects The placement of the wellhead on the seabed, installation of the BOP stack, cement discharges and abandonment of the well provide islands of hard substrata ( artificial reef ) in an otherwise uniform area of unconsolidated sediments.

35 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-35 Description of the potential impact The availability of hard substrata on the seabed provides opportunity for colonisation by sessile benthic organisms and provides shelter for demersal fish and mobile invertebrates thereby potentially increasing the benthic biodiversity and biomass in the continental slope region. Receptors The benthic fauna inhabiting unconsolidated sediments, such as is expected in the area of interest, of the outer shelf and continental slope are poorly known, but at the depths of the proposed well are expected to be relatively ubiquitous, varying only with sediment grain size, organic carbon content of the sediments and/or near-bottom oxygen concentrations. Benthic fauna inhabiting islands of hard substrata in otherwise unconsolidated sediments of the outer shelf and continental slope are also very poorly known. Epifauna living on the sediment typically comprise urchins, burrowing anemones, molluscs, seapens and sponges, many of which are longer-lived and therefore more sensitive to disturbance. No rare or endangered benthic species are known to occur in the project area. Project Controls and Industry Practice The drill contractor would also be required to monitor cement returns and cement pumping would be terminated if returns are observed on the seafloor. Performance objectives Protect sensitive seabed habitats. Impact assessment The presence of the subsea infrastructure (e.g. wellheads and guide bases) would increase the amount of hard substrate that is available for the colonisation of benthic organisms. This may increase biodiversity and biomass in the vicinity of physical structures on the seabed. Shell is proposing to abandon the wellhead(s) on the seafloor at the end of well drilling. Studies have shown that oil and gas infrastructure associated with permanent production platforms provides a sheltering habitat for fish usually associated with complex reef habitats, and infrastructure may positively affect larval production, which could subsequently result in increased recruitment success. The presence of subsea infrastructure (namely two wellheads) could, therefore, alter the community structure in an area. Similarly, but to a lesser extent, solidified excess cement discarded during cementing of the casings would provide hard substratum for benthic organisms to colonise in an environment otherwise dominated by unconsolidated sediments. These alterations to community structure would, however, occur at a much smaller scale than that reported on production infrastructure. While this may have positive implications to certain fish species (e.g. kingklip and jacopever), which show a preference for structural seabed features, it may enhance colonisation by non-indigenous species thereby posing a threat to natural biodiversity. However, due to the water depths in the area of interest, colonisation by invasive species is unlikely to pose a significant threat to natural biodiversity in the deep sea habitats. The increase of surface area afforded by residual cement and abandoned wellheads is small and highly localised (3 m 2 in extent; 3 m high) and is likely to have an impact of low intensity on the benthic macrofauna. The duration of the impact would be permanent. Overall the significance of this impact is considered to be of very low (neutral) significance (see Table 6-16). Mitigation No mitigation measures are proposed or deemed necessary.

36 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-36 Residual impact Due to the abandonment of the wellhead on the seafloor and small volumes of cement anticipated, the impact would remain of VERY LOW (neutral) significance. Monitoring Shell to monitoring discharges of cement to the seafloor around the casing during cementing using a ROV. Table 6-16: Impacts of petroleum infrastructure on marine biodiversity CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Duration Intensity Probability Confidence Significance Local Permanent Low Possible Medium Very Low (neutral) No mitigation is considered necessary Reversibility Mitigation potential Permanent None 6.2 IMPACTS ON THE SOCIO-ECONOMIC ENVIRONMENT LOCAL PROJECT SPENDING Description of the source of impact The table below summarises the project activities that are likely to result in local project spending. Project phase Mobilisation Operation Demobilisation Activity Shell and sub-contractor spending on salaries of local personnel Shell and sub-contractor spending on local non-salary items including: 1. Meeting the needs of non-local personnel when they are ashore 2. Food and other supplies needed to keep the drilling rig/ship and support vessels stocked 3. Other items such as freight and logistics, port fees and fuel The proposed project would result in a temporary spending injection that would benefit the local economy. All expenditures would lead to increased economic activity that would result in direct, indirect and induced impacts on employment and incomes. Taking employment as an example, impacts would be direct where people are employed directly on the project. Indirect impacts would occur where the expenditure associated with a project supports jobs and incomes (e.g. purchasing food and accommodation maintains jobs in those businesses) and induced impacts where jobs are supported due to the expenditure of employees and other consumers that gained from the project. Direct impacts are the most important of these three categories of impact as they are the largest and more likely to be felt in the local area. The overall project has four main components, namely two land-based components in the form of the onshore supply base and helicopter base and two ocean-based components consisting of the drilling unit and a fleet of specialised support vessels. The shore base would be operational for between 9 and 12 months in total - the longest period among the project components. This would include a 6 to 7-month mobilisation phase, followed by the 2-month drilling campaign and a subsequent 3-month demobilisation phase. Shell is yet to decide on the location of the shore base, but currently prefers Lüderitz over Walvis

37 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-37 Bay. The helicopter base would be located in Lüderitz given its proximity to the drilling area. Helicopter base staff would arrive in Lüderitz around a month prior to the start of the drilling campaign and leave soon after the end of the campaign, thus being in the town for about 3 months. The non-local staff working at the shore and helicopter bases would require accommodation at these locations for the duration of their operation. The drilling unit would sail to the drill site with a basic crew and arrive at the beginning of the drilling campaign. At this time the remaining personnel (including drilling company, Shell and contractors) would be flown into Lüderitz, before taking a helicopter flight to the drilling unit. These staff would rotate with their colleagues on a regular basis. The support vessel crews would probably arrive a week or so before the drilling rig and begin preparation for loading supplies. Description of the environmental aspects The project would result in a temporary spending injection that would benefit the local economy. Spending would also be generated by the need for Shell, drilling contractor and sub-contractors to purchase goods and services. Description of the potential impact All expenditures would lead to increased economic activity in Namibia 5 and would be linked direct, indirect and induced impacts on employment and incomes (salaries, fees, rentals, etc.). Receptors The communities living in Lüderitz and Walvis Bay, as well as the businesses operating out of Lüderitz and Walvis Bay, constitute primary receptors, as these parties would be affected the most by the increased economic activity generated by the project. Impacts should also extend beyond these areas to the wider region and country but to a lesser degree. Project Controls and Industry Practice Shell s HSSE & SP Control Framework standards for Social Performance provide for the following: Establishing and maintaining a Social Performance Plan that includes a Social Investment Strategy; and Stakeholder engagement in order to: > Find out stakeholders needs and expectations; > Communicate a procedure to receive, track and respond to questions and complaints; > Seek input on the social impacts of business activities, and on mitigation or enhancement measures; and > Seek feedback on the effectiveness of stakeholder engagement and update plans accordingly. Shell also has various Supplier Principles for contractors and suppliers, including: Business integrity: > Contractors and suppliers are required to comply with all applicable laws and regulations; > Contractors and suppliers should not tolerate, permit or engage in bribery, corruption or unethical practices; > Contractors and suppliers are to support fair competition; and > Conflicts of interest are avoided. 5 The impact associated with project spending outside Namibia (e.g. hire of drilling unit) is not considered in this assessment.

38 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-38 Health, Safety, Security and Environment: > Contractors and suppliers must be committed to protect the environment in compliance with all applicable environmental laws and regulations; > Contractors and suppliers must use energy and natural resources efficiently; and > Contractors and suppliers must minimise waste, emissions and discharge of their operations, products and services. Social performance: > Contractors and suppliers are to respect their neighbours and contribute to the societies in which they operate. Labour and human rights: > Contractors and suppliers are to conduct their activities in a manner that respects human rights as set out in the United Nations Universal Declaration of Human Rights and the core conventions of the International Labour Organisation. Contractors and suppliers should not: Should not use child labour; Should not use forced, prison or compulsory labour; Comply with all applicable laws and regulations on freedom of association and collective bargaining; Should not tolerate discrimination, harassment or retaliation and should provide a safe, secure and healthy workplace; and Should provide wages and benefits that meet or exceed the national legal standards and should comply with all applicable laws and regulations on working hours. Performance objectives Optimise opportunities for recruitment of locals for semi-skilled and general work and procurement of goods and services. Impact assessment The overall project and especially the actual drilling phase would take place over a relatively short timeframe and would require high levels of technical expertise, most of which would come with the drilling unit. The majority of specialised roles would be filled by experienced expatriate personnel. There is, however, the potential for limited opportunities for the employment of Namibians, mostly in general and semi-skilled positions. The total personnel requirements for exploration may be between 170 and 290 people across all project components each of which would have varying durations from 1-2 months up to 12 months. There is the potential that between 15 and 50 of these opportunities could be available for local Namibians and may include the following: At the onshore supply base, there may be options for local employment as general staff (yard crew, port crew and lifting crew), in catering, in cleaning and in logistics for a period of up to 12 months. At the helicopter base, support and other ground staff may be needed for up to 3 months. The drilling contractor and associated service providers may have opportunities for local employment in semi-skilled positions (e.g. electricians, welders and deckhands) and general work positions in catering, cleaning and laundry staff for approximately 2 months. The three support vessels may have opportunities for deck hands and boatswains in particular for approximately 2 months. These employment opportunities could translate into salary payments that provide local incomes in the order of N$ to N$ 1.9 million. Similar to overall project spending on personnel, the largest portion of non-salary spending would be on the procurement of drilling equipment, drilling services and supplies. As there is no developed oil and gas

39 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-39 industry in Namibia, practically all of this procurement would be offshore (i.e. procured from foreign suppliers). There are thus very limited opportunities for procurement of local goods and services and all procurement may be done by a single Namibian supply and logistics company. Potential local non-salary spending elaborated on below may include: Meeting the needs of non-local personnel when they are ashore (i.e. for accommodation, food, transport, entertainment and other items). Food and other supplies needed to keep the drilling unit and support vessels stocked. Other items such as freight and logistics, port fees and fuel. Spending by non-local personnel, when they are ashore or for those that are shore-based, should total between N$ 2.4 million and N$ 4.5 million, roughly one third of which may be on the accommodation of shore base personnel. Spending on food and other supplies for the drilling unit and support vessels should total between N$ 3 million and N$ 4.5 million, 80% of which is assumed to be on supplying the drilling unit. When combined, the aforementioned quantified spending would total between approximately N$ 6 million and N$ 11 million, the majority of which (i.e. 65% to 80%) would be associated with the onshore logistics base. Though not quantified, due to limited data and uncertainties at this stage of project planning, there would also be a need to procure other items locally. These would include: Freight and logistics services; Port fees and associated port services; Airport usage and rental fees at the helicopter base; and Fuel for the drilling unit, supply vessels and helicopters. In addition to the above opportunities associated with direct local spending, temporary indirect and induced opportunities would also be associated with the proposed project. These would stem primarily from the local multiplier effect as spending works its way through the economy. The overall positive impact associated with local project spending is considered to be primarily regional, of low intensity over the short-term for both the onshore logistic base alternatives, namely Lüderitz or Walvis Bay. Thus the potential impact is considered to be very low (positive) without mitigation (see Table 6-17). Mitigation Information-sharing by Shell is important to ensure that unrealistic expectations are managed. Shell would appoint a Namibian marine logistics company to handle in-country logistics, labour requirements, services to the onshore base, secure space at the harbour for the logistics base and manage the base. The following mitigation measures would be implemented: No. Mitigation measure Classification 1 Inform stakeholders on the project database, especially the local Town Council from the selected town where the onshore logistics base will be located, when Shell has made a decision to proceed with drilling. The timing and duration of the project and opportunities for jobs and procurement of goods and services should form part of the information provided. 2 Define local content (employment and procurement) objectives in the contracts with all contractors. Abate offsite/at receptor Abate offsite/at receptor Residual impact With the implementation of the project controls and mitigation measures, the residual impact is considered to be of low (positive) significance for the drilling of a single well. If a second exploration well is drilled, the combined impacts of both wells would be of low to medium (positive) significance. However, considering the precautionary principle and the possibility that the second well may not be drilled, this assessment assumes a residual impact of LOW (positive) significance.

40 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-40 If measured relative to the local economy, the positive impact would be greater if the shore base is located in Lüderitz. Table 6-17: Impacts associated with project expenditure CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent Regional Regional Duration Short-term Short-term Intensity Low Medium Probability Definite Definite Confidence High High Significance Very Low (+ve) LOW (+VE) Reversibility Optimisation potential Partially reversible (should spending stop) Low MACRO-ECONOMIC VARIABLES Description of the source of impact Shell would be required to make various payments to the Namibian government. The table below summarises the project activities that are likely to result in revenue for Namibia and affect the balance of payments. Project phase Mobilisation Operation Demobilisation Activity Payment of government exploration licence area rental charges Project spending leading to increased indirect tax receipts Project spending affecting the balance of payments positively Description of the environmental aspects The project would result in payments to government in the form of licence and rental charges and indirect taxes, as well as changes to Namibia s balance of payments (i.e. the difference in total value between payments into and out of a country over a period). Description of the potential impact Namibia s national government would realise a slight increase in income and the balance of payments would be positively affected. Receptors The receptors of macro-economic impacts include the national fiscus, as well as the Namibian economy as a whole. Project Controls and Industry Practice In terms of the Shell s General Business Principles it aims to act in a socially responsible manner within the laws of the countries in which it operates in pursuit of its commercial objectives. Shell companies do not make payments to political parties, organisations or their representatives. Shell does not take part in party politics. However, when dealing with governments, it has the right and the responsibility to make its position known on any matters, which affect Shell, its employees, its customers, its shareholders or local communities in a manner, which is in accordance with its values and the Business Principles. Also refer to Section

41 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-41 Performance objectives Contribute positively to the Namibian macro-economy in the form of exploration licence payments, taxes receipts and net capital inflows. Impact assessment Impacts in terms of macro-economic variables encompass revenues from government licence area rental charges, tax receipts and on the balance of payments. The applicants would be liable for an annual petroleum licence area rental charge for exploration of approximately N$1.1 million per year for the next two years increasing to approximately N$1.5 million per year thereafter until 2021/2022. The latter higher fee associated with a second renewal period would be more likely to apply if a second exploration well is drilled. During exploration, royalties would not apply and, as exploration does not directly generate income, direct taxes on company incomes/profits would also not apply. There would, however, be indirect benefits to the fiscus. These are likely to be relatively modest and should primarily take the form of VAT and income taxes levied on direct and indirect project expenditure in Namibia, as assessed in Section The project would have a necessarily high import content given its specialised nature. However, it would also be associated with moderate amounts of local expenditure, as assessed in Section 6.2.1, leading to a positive impact on the balance of payments. Balance of payments benefits would largely be confined to a potential future production phase. The overall positive impact on macro-economic variables is considered to be national, of very low intensity over the short-term. Thus the potential impact is considered to be very low (positive) without mitigation (see Table 6-18). Mitigation No specific mitigation is recommended beyond that outlined in Section focused on ensuring that Shell develops local content objectives in its contracts with its service providers, in which Namibian job seekers and suppliers of goods and services are favourably considered. Residual impact The residual impact is considered to remain be of very low (positive) significance for the drilling of a single well. If a second exploration well is drilled, the combined impacts of both wells would be of low (positive) significance. However, considering the possibility that the second well may not be drilled, this assessment assumes a residual impact of VERY LOW (positive) significance. Table 6-18: Impacts on key macro-economic variables CRITERIA WITHOUT MITIGATION WITH MITIGATION Extent National National Duration Short-term Short-term Intensity Very Low Very Low Probability Definite Definite Confidence High High Significance Very Low (+ve) VERY LOW (+VE) Reversibility Mitigation potential Partially reversible Low

42 SLR Environmental Consulting (Namibia) (Pty) Ltd Page COMMERCIAL FISHING Exclusion from fishing grounds Description of the source of impact The table below summarises the project activities that are likely to affect the fishing industry by exclusion from fishing grounds. Project phase Mobilisation Operation Demobilisation Activity Transit of drilling unit to drill site Operation of drilling unit at the drill site Abandonment of wellhead(s) on seafloor Transit of drilling unit from drill site These activities are further described below: A drilling unit is considered to be an offshore installation and a vessel restricted in its ability to manoeuvre, and as such it is protected by a 500 m safety zone (i.e. an exclusion area of km 2 ). Power-driven and sailing vessels are required to give way, and vessels engaged in fishing are required to, so far as possible, keep out of the way of the well drilling operation. Passage to and from the drill site has a very low risk of impacting fishing (temporary avoidance), although it cannot be excluded in its entirety, as the passage to the drilling location would require crossing trawling and other fishing grounds and fishing vessels may be temporally displaced from operating in a preferred area. After the wells have been sealed, tested for integrity and abandoned, the wellhead(s) (with a height of 3 m and a diameter of 1 m) would be left on the seafloor. Description of the environmental aspects The implementation of the safety zone around the drilling unit would effectively exclude fishing vessels from accessing fishing grounds within 500 m of the drilling unit. The abandonment of the wellhead on the seafloor would also pose an obstruction to any fishing activity directed towards the seabed (namely any demersal fishery). Description of the potential impact Possible impacts on fishing include: The exclusion of fisheries from the safety zone would effectively reduce fishing grounds, which in turn could potentially result in a loss of catch and/or increased fishing effort; and The abandonment of the wellhead on the seafloor would pose an obstacle thereby reducing fishing grounds for the demersal trawl fishery, resulting in a potential loss of catch and damage to fishing gear. Receptors An overview of the Namibian fishing industry and a description of each commercial sector is presented in Section The majority of fishing effort is directed inshore of the m isobath inshore of the area of interest. Only one fishery, the large pelagic long-line sector (see Figure 6-4), overlaps with the area of interest. None of the other fishing sectors are expected to be affected by the proposed exclusion zone.

43 SLR Environmental Consulting (Namibia) (Pty) Ltd Page 6-43 Figure 6-4: Location of the licence area and area of interest in relation to large pelagic long-line effort off the coast of Namibia ( ) Project Controls and Industry Practice Under the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS, 1972), a drilling unit that is engaged in underwater operations is defined as a vessel restricted in its ability to manoeuvre, which requires that power-driven and sailing vessels give way to a vessel restricted in her ability to manoeuvre. Vessels engaged in fishing are required to, so far as possible, keep out of the way of the well drilling operation. Furthermore, in terms of the Petroleum (Exploration and Production) Act, 1991 a drilling unit is considered to be an offshore installation and as such it is protected by a 500 m safety zone. It is an offence for an unauthorised vessel to enter the safety zone. The temporary 500 m safety zone around the drilling unit would be enforced at all times. The safety zone would be described in a Notice to Mariners as a navigational warning. The safety zone would be issued as a navigational warning via the South African Navy Hydrographic Office (HydroSAN) and Lüderitz Radio. Support vessels with appropriate radar and communications would be used during the drilling operation to warn vessels that are in danger of breaching the exclusion zone. Performance objectives Effective communications with key stakeholders to achieve zero incidents and ensure navigational safety. Impact assessment Given the offshore location of the area of interest, the impact of exclusion from fishing grounds is likely only to affect the large pelagic long-line sector. Over the period 2005 to 2015, an average of four lines per year