The LNG operations in the Niger Delta by klutzfu59


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2.1       Introduction to Nigeria LNG Ltd

         The LNG operations in the Niger Delta
         comprise (a) ‘upstream activities’, i.e. the
         production of natural gas by several oil &
         gas producers, (b) transport of the gas
         through a network of onshore and offshore
         pipelines to Bonny Island, and (c)
         ‘downstream activities’, i.e. the gas
         liquefaction at the LNG complex at Finima.

         NLNG was incorporated in 1989 and tasked
         with the harnessing of Nigeria’s vast natural
         gas reserves. The company shareholding
         comprises National Nigerian Petroleum
         Corporation (NNPC) 49%, Shell Gas B.V
         (Shell) 25.6%, Total (15%) and ENI (10.4%).

         NLNG is committed to Sustainable
         Development (SD) – policy issued August
         2003 (see Appendix 3) and Management
         has established a Sustainable Development
         Co-ordination Committee (SDCC) to steer
         developments in this area and to co-ordinate
         and integrate NLNG’s community assistance
         and environmental protection activities. The
         Company has a systematic and rigorous
         approach to HSE Management that is guided
         by the HSE Policy (see Appendix 2). HSE              Figure 2.1 Situation of the NLNG site along the west
         Management is implemented through the                               coast of Bonny Island
         company HSE Management System (HSE-
         MS). In this context, the first and second process trains at the Bonny Island site have achieved
         certification to the International Standard for Environmental Management, ISO 14001. NLNG
         plans to extend the certification to the Gas Transmission System (GTS-1) and future trains.

         The Company is also committed to work constructively with local communities and organisations
         to minimize adverse effects of constructing, developing and operating the LNG plant, while
         maximizing potential benefits for local communities and the environment. The defined objective is
         “to be the catalyst for sustainable development of our host communities”.

         NLNG has a Community Relations Plan that is approved by the Board of Directors of the
         Company. The Plan documents community development and community assistance activities for
         Bonny and the GTS communities. The SD Co-ordination Committee (SDCC) has the task to
         review performance of the Community Relations Plan and to report to NLNG Corporate

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2.1.1    Location

         The Nigeria Liquid Natural Gas (NLNG) plant is located on the western coast of Bonny Island
         (see Figure 2.1), approximately 40 km south of Port Harcourt, Rivers State, Nigeria. The location
         of the site is on the eastern bank of the Bonny River tidal inlet, about 3 km north of its confluence
         with the Atlantic Ocean in the Bight of Bonny. The plant site is situated between the existing
         SPDC’s (Shell Petroleum Development Company) Bonny crude oil terminal (BCOT) in the north
         and the Mobil LPG site in the south.

         The area of land between Bonny Town and New Finima has long been owned by the local
         communities. On a 99 years long-lease basis the land is currently used for industrial activities by
         NLNG, SPDC, Mobil and NNPC (see Map 1).

2.1.2    NLNG plant development status – project history

         NLNG currently owns and operates a 3-train LNG complex at Finima on Bonny Island Nigeria;
         see also Figure 2.2. The NLNGBase project comprised two trains, of which the first was
         successfully taken into operation in September 1999 and the second in February 2000. The third
         train was started up in November 2002, as part of the NLNGExpansion project, which also
         includes facilities to produce LPG. This created the capability of accepting oil-associated gas,
         which had to be flared off in the past. This expansion means an increase in production capacity
         as well as an improved efficiency in the exploitation of the Nigerian gas reserves, with overall
         reductions of greenhouse gas emissions.

         A further expansion of the NLNG complex with two trains is referred to as the NLNGPlus project.
         This project is currently in the early construction phase. Start-up of these two new trains is
         foreseen in the second and fourth quarter of 2005, respectively.

         The addition of a sixth LNG train and associated infrastructure is currently proposed (known as
         the NLNGSix project) and will integrate with the existing NLNG plant. The resulting plant will be a
         six train LNG plant with condensate, Liquefied Petroleum Gas (LPG) and LNG production,
         storage and loading facilities capable of a total hydrocarbon output of 25.7 million tonnes per
         annum (Mtpa).

         Each of the three development phases of the LNG plant have been subjected to an
         environmental impact assessment (EIA) process.

         •    The EIA for the Base Project (trains 1 and 2 and associated facilities and infrastructure) was
              undertaken by EAU (Environmental Advisory Unit), later named SGS Environment Limited of
              Liverpool, UK. Work was commissioned in August 1994 and completed in September 1995.
              The Nigerian Federal Environment Protection Agency (FEPA) approval was granted in
              November 1995.
         •    The EIA for the Expansion Project (train 3 and associated facilities) was also undertaken by
              SGS Environment Limited. Work was commissioned in September 1998 and completed in
              July 1999. FEPA approval was granted in August 2001.
         •    The EIA for the Plus Project (trains 4 and 5 and associated facilities) was commissioned in
              October 2001 (based on baseline studies commissioned earlier) and completed in January
              2002 [14]. This EIA has been undertaken by Ecosphere Nigeria Ltd and Babsal & Company
              Ltd. Approval of the Federal Ministry of Environment (FMEnv) was granted in January 2003.

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          Figure 2.2. View from south-west over the NLNG plant in May 2003. North East of the 3 LNG train the area prepared for
                                          the construction the fourth and fifth trains can be seen.

2.2       NLNG plant process and shipping

         The liquefaction of natural gas makes it possible to ship gas in liquid form to faraway markets
         which are out of reach for conventional transport by pipeline. Liquefied Natural Gas (LNG)
         approximately occupies only 1/600th of the volume of natural gas at atmospheric pressure and
         temperature, that is to say that one LNG ship with an average volume of 125,000 m3 of liquid is
         equivalent to some 75 million m3 of gas at standard conditions.

         The LNG plant is in fact a big fridge. In the box of dotted lines in Figure 2.3 the main process
         steps are shown for train 6. Processed gas enters the plant through the Gas Transmission
         System (GTS), which will consist of 3 different systems for the 6-train LNG plant. Subsequent to
         entering the plant, slugs of liquid are trapped by the Slug Catcher whilst the processed gas
         continues to flow into the plant. The liquid recovered from the slug catcher is too heavy in
         composition to be acceptable for inclusion in the LNG production. Therefore, this liquid or
         condensate is stored in a dedicated condensate tank for subsequent export.

         The heavier hydrocarbon components such as Liquefied Petroleum Gas (LPG) and Condensate
         are also removed (Fractionation) within the LNG train to meet the very exact quality
         specifications imposed on NLNG by its customers.

         Prior to liquefaction, gas is processed in each LNG train to
         • remove hydrogen sulphide (H2S) and carbon dioxide (CO2), if present (acid gas removal),
         • remove water (dehydration)
         • remove mercury, if present (mercury removal)

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                              Figure 2.3. Plant block scheme showing generic LNG process in train 6.

         Liquefaction occurs in two refrigeration cycles in use at the NLNG Plant. The first cycle, the pre-
         cooling cycle, uses pure propane as a refrigerant and chills the natural gas to minus 35°C.

                                           Capacity LNG
         Projects        LNG trains                           Feed Gas           Tanks             Jetties          Cooling
                                                                                                  LNG Jetty
                                                                                  2 LNG
         Base                1, 2              6.4              NAG                           (incl. condensate   Water cooled
                                                                              2 condensate
                                                                                 1 LNG
         Expansion     3 + fractionation       3.2            NAG, AG                             LPG Jetty       Water cooled

                                                                                                   LNG jetty
         Plus                4, 5              8.2            NAG, AG                                              Air cooled
                                                                                               (relocated MOF)
                                                                                 1 LNG
         Six                  6                4.1            NAG, AG         1 Condensate                         Air cooled
                                                                                  2 LPG


                               Table 2.1. Main elements and characteristics of the 6-train NLNG plant.

         The second cycle, the liquefaction cycle, uses a mixture of components (nitrogen, methane,
         ethane and propane in varying proportions). This refrigerant, called Mixed Refrigerant, chills and
         liquefies the Natural Gas from minus 35°C to minus 161°C. The liquefied gas is stored at -160ºC

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         in above-ground atmospheric tanks with a gross capacity of 84,200 m3 each. From there it is
         pumped via the loading jetty into the LNG carriers (LNGCs) ready for export.

         In Table 2.1 all relevant characteristics are listed of the NLNG operation after start-up of the last,
         sixth train. The total LNG capacity will be almost 22 Mtpa LNG. Half of the trains will be water-
         cooled and the 3rd, fourth and fifth trains air-cooled. The total number of storage tanks on site will
         amount to: 4 for LNG, 3 for condensate, 4 for LPG and 1 bunker fuel tank.

         By the end of 2007, with a 6-train operation, the NLNG site is expected to increase the marine
         traffic through the Bonny Channel with a total of about 350 LNG carriers, 76 LPG ships and 39
         condensate tankers per year.

2.3       The NLNGSix Project

2.3.1     The case for Train 6

         The need to reduce emissions of global warming substances to the atmosphere, such as CO2
         and methane (CH4) is now a generally accepted concept. At the Rio Conference in 1992, the Rio
         Declaration of general principles (non-binding) outlined commitments including the Framework
         Convention on Climate Change (1992) (see This Convention sets out the
         framework law under which the subsequent Kyoto Protocol was developed. The Kyoto Protocol
         (adopted 1997) sets out binding agreements for emissions to the atmosphere including individual
         requirements such as reduction targets on such emissions. As part of its commitment to the Kyoto
         Protocol Nigeria has set national targets of cutting out flaring relating to oil production by 2008
         and NLNG is one of the crucial players who will be instrumental to the success of the
         Government’s flare out plan. When all 6 trains are operative it is estimated that the plant will
         consume about 3 bcf/y1 oil-associated and non-oil-associated gas, a significant proportion of
         which would otherwise have been flared and lost to the atmosphere, against an estimated 2.4
         bcf/y flaring level in Nigeria at inception of the project.

2.3.2     Project alternatives

         Nigeria is endowed with the tenth largest proven natural gas reserves. These gas reserves are, in
         energy terms at least twice that of crude oil reserves. Presently (mid 2003), Nigeria’s oil and gas
         reserves stand at 26.5 billion barrels2 of oil and 159 trillion cubic feet (tcf) of gas and potentials in
         excess of 200 tcf.

         Starting from the prerequisite that for economic reasons natural gas should be produced in
         Nigeria, questions about alternatives have to deal with interrogative pronouns as “where(to)”,
         “how” and “why”.

         Alternative routes / markets for natural gas.

         The country faces a number of difficulties in harnessing its abundant gas reserves. Probably the
         biggest constraint to gas development is the lack of ready markets for the commodity. Domestic
         gas demand is a meagre 300 million cubic feet per day, in a country where few households have
         modern cooking appliances and most still use traditional, cheaper forms of energy. Similarly to
         stimulate the domestic consumption of natural gas, government is reactivating dormant gas
         utilisation projects such as power, steel, aluminium and fertilizer plants as well as encouraging the
         building of independent power plants. Significant markets for natural gas can only be used
         through export of the hydrocarbons.

             bcf/y = billion cubic feet per year; 1 bcf = 0.03 billion Nm3
         2                       3
             1 barrel = 0.16 m

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         Alternative export methods.

         The major international gas markets are located in Europe and Asia. In view of the distances to
         be bridged, exports of Nigerian gas in the form of LNG is the only way to transport gas to these
         markets. In addition, export of gas will diversify Nigeria's exports, which are currently based
         almost totally on oil.

         Process and lay-out alternatives.

         During the earliest project development phases, alternatives have been evaluated. The result
         thereof and the requirements to align with the trains 1-3, as well as the need to apply Best
         Available Technology, have led to the selected process, preferred design and lay-out of the 6th
         train and slug catcher. See also section 2.4.

         Why now gas production and export.

         Export of gas will also boost the utilization of a hitherto wasted resource, i.e. the associated gas.
         All the major oil companies operating in Nigeria have resolved to reduce flaring of this gas. Their
         programmes include increasing the volume of associated gas re-injected into oil reservoirs,
         reducing oil production from wells with high ratios of gas to oil, and fitting more efficient flare tips
         to flares. Associated gas, which is produced at low pressure and must be compressed and
         treated in facilities specifically built for the purpose, is one of the most difficult and expensive gas
         sources to harness. In Nigeria, it requires a network of compression facilities and pipelines to link
         scattered fields that do not produce sufficient quantities of gas to be commercially viable on their
         own. Though initially the LNG plant has processed mostly non-associated gas, the proportion of
         associated gas used is expected to increase significantly with additional LPG facilities, such as in
         the NLNGSix project, to be built.

         No project.

         The NLNGSix project will also use oil-associated gas, which is currently flared. The capture of
         flared gas by NLNGSix will add to that of Trains 3, 4 and 5 and will ensure that Nigeria does not
         waste (by flaring) what is a potentially valuable natural resource. Reduction in flaring due to gas
         capture by liquefaction plant will also result in very significant environmental improvements
         through lower the levels of greenhouse gas emissions in the Delta. The “no project” option would
         mean that further capture of associated flared gas would not be available.

         In conclusion: there are no economically and technically feasible alternatives for export of natural
         gas other than through transport after liquefaction and the only way to stop the current flaring of
         associated gas within the foreseeable future is to use the available gas transport, treatment and
         export systems, i.e. LNG and LPG facilities.

2.3.3    Scope of the NLNGSix Project

         The NLNGSix project consists of:

         •    the construction and operation of a new (sixth) liquefaction train, which is an extension to the
              current NLNGPlus project; this train is a carbon copy of trains 4 and 5, plus associated
              facilities, additional storage facilities and tie-in with the original Bonny Island LNG plant
         •    the construction and operation of the GTS-2/4 Slug Catcher, which is actually an add-on to
              trains 4 and 5; this slug catcher is meant to receive, separate and distribute the two-phase
              gas/condensate mixture delivered by the GTS-2/4 system.

         The elements of the NLNGSix Project are indicated in Figure 2.6 in green, whereas the
         NLNGPlus parts are in red. The GTS-2/4 slug catcher is situated just north of the 3rd and fourth
         LNG tank.

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         The Project does not include the so-called “Channel Deepening”, i.e. the improvement and
         deepening of the offshore approach channel to Bonny River and Bonny Island. A separate
         Environmental, Social and Health Assessment (ESHA) will be carried out for these activities with
         a focus on the deepening of the approach channel and all marine operations and shipping during
         a full-plant LNG production.

2.3.4     Project schedule

         The NLNGSix Project has been scheduled (see Table below) to be completed in a very short
         timeline. This is only possible because train 6 is a carbon copy of the trains 4 and 5. After a
         Scouting Study in the last quarter of 2002, the Basis-of-Design (BOD) was completed by end April
         2003. The Project Specification has been completed by mid September, whereas the Final
         Investment Decision (FID) is scheduled for end July 2004, after which the EPC contract - the
         contract for Engineering, Procurement and Construction - will be awarded. Start-up is scheduled
         for end 2007.

                                        CONSTRUCTION/COMMISSIONING SCHEDULE

                             SCOPE                           WORK ELEMENT              START DATE   FINISH DATE

                CONSTRUCTION                                                             May 04       Oct. 07
                                   Sub-Contracts                                         May 04       Oct. 06
                                                      soil monitoring                    May 04       July 04
                                                      site preparation – pre-loading     May 04      Aug. 04
                                                      building & Offsite civil works     July 04     Dec. 04
                                                      insulation                         Oct. 04      July 05
                                                      painting                           Oct. 04      Oct. 05
                                                      NDT & inspection                   Oct. 04      July 05
                                                      telecoms (permanent)               Oct. 04      Oct. 06
                                 Offsites/Utilities                                      Oct. 04      May 07
                                                      preload GTGs                       Oct. 04     June 05
                                                      foundations/buildings              Jan. 05      Jan. 06
                                                      structural steel/buildings         Sept. 05     May 06
                                                      mechanical equipment               Oct. 05      Oct. 06
                                                      painting & insulation              Aug. 06     Feb. 07
                                                      telecommunications                 Oct. 06      May 07
                                           Train 6                                       Aug. 04      Oct. 07
                                                      preload                            Aug. 04      May 05
                                                      foundations/buildings              June 05      Jan. 07
                                                      structural steel/buildings         Oct. 05     March 07
                                                      mechanical equipment               Jan. 06     March 07
                                                      painting & insulation              Jan. 07      Oct. 07
                                        LNG tank      start construction                 Aug. 04
                                                      mechanical complete                             June 08
                                 Condensate tank      start construction                 Aug. 04
                                                      mechanical complete                             Oct 06
                                       LPG tanks      start construction                 Aug. 04
                                                      mechanical complete                             Jan 08

                COMMISSIONING                                                            Oct. 06      Oct. 07
                                                      utilities/offsites                 Oct. 06      Apr. 07
                                                      Train 6                            Feb. 07      Oct. 07

                Ready For Start-Up (RFSU)             Train 6                                         Oct. 07
                                                      LNG                                             July 08
                                                      Condensate                                      Nov. 06
                                                      LPG                                             Feb. 08

         The Slug Catcher schedule is completely independent of the train 6 development. The EPC
         management contract award was in early 2004 and by the end of 2005 the slug catcher will be
         Ready For Start-Up (RFSU).

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2.3.5    Project economics and societal investments

         Total capital investment for the sixth train of the NLNG plant will be approximately USD 1 billion,
         most of which will be spent in the period up to 2006. The operating costs will be about USD 75
         million per year. The lifetime of the project is 20 years. The current cost estimate for the slug
         catcher is USD 50 million.

         Nigeria will benefit from the sixth train through additional dividends to their shareholder NNPC:             Deleted: party
         USD 220 million or some NGN 15.6 billion annually throughout the lifetime of this project. On top
         of this, the country will also benefit from additional sales of feed gas and additional taxation after

         Nigeria LNG has committed itself to maximising Nigerian procurement of labour, materials and
         equipment. This investment is expected to have an important (but immeasurable) catalytic effect
         on attracting future foreign investment to Nigeria as other potential investors will view and judge
         their success or failure as a measure of country risk and act accordingly.

         Multiplier effects result from associated economic activity such as services, accommodation etc.
         International and Nigerian experience from similar large-scale projects suggests that the multiplier
         effect can be in the order of 2 to 4.

         During construction and operations a large number of temporary construction jobs will be created,
         as well as a smaller number of new long-term permanent positions on Bonny Island; similar to the
         situations of the Base, Expansion and Plus projects.

         NLNG, TA and Contractors (PS or EPC) are committed to maximising Nigerian content for the
         NLNGSix project and to stretch beyond the target set for the construction of the Plus project,
         where 78% was realised. In terms of man-hours for the construction of the sixth train, the Nigerian
         content target is set at 84%. Accordingly, a Nigerian Content Plan Six (NCPS) will be prepared,
         during the Project Specification (PS) phase, by these three parties with each individual company
         being responsible for the development and implementation of the plan.

2.3.6    Train Six details

         The NLNGSix project centres around the addition of a sixth LNG train to the 5-train plant.
         Additional components that are required in order to handle the additional capacity Train 6 will
         provide include:

         • Storage
           • LNG tank:
              The fourth LNG tank will be a carbon copy of the existing 3 LNG tanks, being an above
              ground, full containment type of tanks. The tank is built up of a 9% nickel steel inner tank
              and a concrete outer tank. Dimensions: 61.3 m outer diameter and 48 m height, with a net
              volume of 84,000 m3. The tank is operated containing LNG of a temperature of -162ºC.

             • LPG tanks
                One propane and one butane tank are included in the project, which are carbon copies of
                the existing propane and butane (LPG) tanks 1 and 2. These tanks are above ground,
                full containment type, of Low Temperature carbon steel inner and outer tank shells.
                Dimensions: 56.8 m outer diameter and 38 meters height, with a net volume of 65,000 m3
                for each tank. The butane is stored at minus 5ºC and the propane is stored at minus 42ºC.

             • Condensate tank

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                   The third condensate tank is a carbon copy of the two existing condensate tanks. The tank                                  Formatted: Bullets and Numbering
                   is a carbon steel floating roof tank. Dimensions: 60 m diameter and 16.3 meters height.
                   The net volume of the tank is 36,000 m3. The condensate is stored at ambient temperature.

         • Condensate stabilisation facilities

         • One LPG chilling module

         • Utilities
           • Fuel gas booster compressor.                                                                                                     Formatted: Bullets and Numbering
           • Nitrogen storage.
           • Instrument air system expansion.
           • Gas turbines for power generation.

         The sixth LNG train will be designed as a carbon copy of the fourth and fifth LNG trains’ final

         Overall plant feed rates and product run-down will vary. LNG production will vary for different feed
         gas compositions and ambient air conditions. This is summarized in Table 2.2 per train for the
         average, lean and rich feed gas design cases. Note that production figures given are for train 6
         based on a carbon copy of trains 4 and 5.

         The exact quantity of LNG delivered by the plant also depends on the combination of a large
         number of factors including feed gas availability, liquefaction plant capacity, storage at the plant,
         operational and environmental constraints on and interruptions to shipping, customer demands
         and the facilities available at the buyer's reception terminal.

            Design Case                                                        Case 1            Case 2               Case 3

            Gas composition                                                   Average             Lean                 Rich
            Ambient air temp                                 [°C]               28.5               36                      23

            (1) Feedgas                                    MMscfd                667              601                  709
                                                            [t/sd]            16,048             14,477               17,078
            (2) LNG rundown                                 [t/sd]            11,990             11,699               12,235
            (3) Propane rundown                             [t/sd]               622               120                     880
            (4) Butane rundown                              [t/sd]               928               215                 1169
            (5) Pentane draw-off                            [t/sd]               111                0                      102
            (6) Fuel gas for train 4 (or 5)                 [t/sd]               900               898                     909
            (7) Fuel gas export                             [t/sd]               475               475                     475
            (8) Acid gas                                    [t/sd]               448               645                     563
            (9) Condensate rundown                          [t/sd]               574               425                  745
                                                            bbl/d               5598              4145                 7265
            Note: MMscfd = million standard cubic feed per day; t/sd = tonnes per standard day

                             Table 2.2. Variation of train six production for various scenarios of feed gas composition.

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                                                           Trains 1,2,3
                      1569 MMscfd

                                                    Acid Gas
                                                                                        7       Fuel
                                                           8                           10       Endflash

                        2002 MMscfd
                                                                                                               2      LNG

                                1                                                                              3     Propane
                                                            Trains 4,5,6
                                                                                                               4      Butane

                                                                                                               5      Pentane

                                                         11           12
                                                                                                               9      Condensate

                                      Figure 2.4. Production flows for references in Table 2.3.

         The resulting six train LNG plant will have an overall total hydrocarbon production capacity of
         approximately 25.7 million tonnes per annum (Mtpa) (product production rate breakdown shown
         in Table 2.3 below).

                                                      Daily Production           Annual Production
                                                       Capacity (t/d)             Capacity (Mtpa)

                                  LNG                       64,400                      21.80

                                Propane                      3,400                       1.17

                                 Butane                      4,800                       1.62

                                                             3,400                       1.14
                              Pentane NNF

                                TOTAL                       76,000                      25.73
                          Note: NNF = Normally No Flow (pentane expert is not foreseen and is a future
                                                     contingency only).

                                  Table 2.3. The full NLNG plant (six trains) production capacity.

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2.3.7     Slug Catcher details

         As part of the NLNGPlus project, a slug catcher will be added to the complex to receive the feed
         gas from the Gas Transmission Systems 2 and 4. The slug catcher is designed to cater for the
         slugs of liquid coming from these pipelines; see Figure 2.5 for an example of a slug catcher.

              Figure 2.5. An example of a slug catcher. This “Den Helder” slug catcher is operated by NAM in The Netherlands.

         The total liquid capacity of the slug catcher is 1250 m3. Any received liquid is pumped to the
         stabilization unit, after which the processed part of the liquid is sold as condensate. The gas is
         sent to the liquefaction trains.
         The slug catcher with associated receiving facilities consists of:

         •     An inlet manifold, where the two pipeline systems (GTS-2 and GTS-4) are joined
         •     Two pig receivers for pigs coming out of the two Gas Transmission Systems
         •     10 parallel “fingers” (the pipelines that receive, separate and temporarily store the liquid),
               inner diameter 40 inch, length ~185 meter
         •     4 Pressure Letdown Control Valves
         •     4 Feed Gas Separator Vessels (to separate the liquid that condensates downstream of the
         •     Metering devices to fiscally meter the gas and the liquid that flows from the slug catcher and
               feed gas separator vessels into the plant.

         The slug catcher, including all associated facilities, will take up an area of approximately 365m x
         60 m.

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2.4      Project design aspects

2.4.1    Plant Specification

         The basic design of the LNG Base, Expansion and Plus projects contain features which are
         required to ensure high standards in pollution abatement, effluent and environmental control. It
         contains provisions for enhancing safety and integrity of the plant, so as to minimise the
         probability of any failure during operations and to limit the undesirable consequences in the event
         of their occurrence. These design features will also apply to NLNGSix. Typical features to ensure
         high standards of pollution abatement, similar to the trains 1-5 include impermeable floors in
         process areas, drainage with separate systems for contaminated and uncontaminated streams,
         both physical (oil-water separators) and biological (biotreater) wastewater treatment, vent stacks
         only for emergency venting, etc.

         Application of the best available technology was in the design philosophy of the Base,
         Expansion and NLNGPlus trains, such that the project provides for safety, reliability, flexibility
         and efficiency, in that order. As such, the highest standards currently recognised by the
         international gas industry have been applied in the design of the complex. This includes principles
         such as the minimisation of the number of flanges in piping, adequate separation distances in
         plant layout and automatic leak detection and safeguarding systems. These standards will also
         apply to the NLNGSix project.

         The design, engineering, procurement and construction of project facilities are in accordance with
         sound, professional engineering practices throughout. It has been based on stipulations laid down
         in Shell Design and Engineering Practices (DEPs) in conjunction with relevant applicable
         international codes and standards, and governing or limiting Nigerian Government Authority
         Legislation, Regulations, Codes and Standards.

         Management of HSE requirements and implementation of the HSE Premises (see also Section
         2.4.2) during both construction and operation phases of the project will be achieved through the
         implementation of an HSE Management System, in common with the approach taken during the
         Base, Expansion and Plus projects.

         In addition, quality assurance and control will be strictly enforced upon the contractors, sub-
         contractors and suppliers for the engineering, procurement, construction (EPC) and start-up
         phases of the project, using the concepts of the international quality system standards ISO 9001
         & ISO 9002.

2.4.2    Health, Safety and Environmental Premises

         In the Basis-of-Design (BOD) for the NLNGSix project a section with the HSE Premises is
         presented; see Appendix 4. The requirements presented in this section will ensure that the design
         is in line with currently accepted social (including health), safety and environmental and Human
         Factors Engineering (HFE) standards applicable to this project. NLNG aims to have an exemplary
         HSE performance, to earn the confidence of customers, shareholders and society at large, to be
         a good neighbour and to contribute to sustainable development.

         This is to be achieved by complying with:

         •    all relevant Nigerian statutory requirements
         •    policies issued by Nigeria LNG Ltd. on Health, Safety and the Environment (HSE and
              Sustainable Development (SD)
         •    policies and principles issued by the joint venture partners, including Shell Group and Shell
              Gas & Power Business policies, standards and guidelines
         •    internationally accepted norms and standards
         •    World Bank's Environment, Health and Safety guidelines

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         •     international agreements to which Nigeria is a party

         The aim is:

         •     to prevent/minimize injuries, ill health, damage to assets and the (natural and social)
               environment by appropriate management of risks
         •     to avoid/eliminate liabilities in the future and to meet requirements for due diligence
         •     to take advantage of opportunities to improve the working environment for staff and

         The HSE Premises for train Six are detailed in Appendix 4. The HSE Premises for the slug                  Comment [RJ1]: Page: 11
         catcher have been issued in a similar manner and do have a similar content, but are not attached          Insert HSE Premises as Appendix

         to this report.

         HSE Premises reflect the operating philosophies of NLNG and are set as a minimum set of
         standards for installations and operations. HSE Premises may will be refined and/or extended as
         a result of the formal HSE deliverables to be produced during the successive project development
         phases. The project will use the Shell HEMP (Hazards and Effects Management Process) and
         undertake a full suite of studies to identify hazards and predict their consequences. These studies
         include, but are not limited to, HAZID, HAZOP, Technical Desk HSE Review, Health Risk
         Assessment, ESHA, Human Factors Engineering in new projects and Quantitative Risk
         Assessment (QRA). All risks to people, assets, reputation and the environment will be reduced in
         compliance with the principal of As Low As Reasonably Practicable (ALARP) and will be
         managed through continuous improvement.

         The standards for the design and operations have been discussed and agreed with the relevant
         Nigerian authorities. As a result of the adopted design standards, the project complies with all
         relevant Nigerian legislation and standards, up-to-date and stringent HSE requirements, in line
         with World Bank pollution standards and guidelines on occupational health and safety matters.

         HSE requirements within Nigerian legislation have also been analysed for applicability during the
         construction phase of the project. Standards relevant for construction are as HSE Premises for
         Construction part of the Project Specification (PS); these premises are detailed in Appendix 5.

2.4.3     Access management

         The overall potential risk posed by the LNG plant operation to third parties and the wider
         environment is managed through a number of methods including various levels of control of areas
         within close proximity to the LNG plant. The extent of the areas for different controls is determined
         through the use of NLNG criteria for managing this risk and is defined in Company project
         information. In the Quantitative Risk Assessment (QRA) report (Appendix 12) the calculations are
         presented and the range of zones identified, the most notable being the Safety Zone and the
         Sterile Zone (see Figure 2.6). These zones are established to restrict certain activities depending
         on proximity to the NLNG plant:

         •     The Safety Zone (bounded by the 10-5 risk contour) is defined as an area where no other
               activities should take place. No public access is allowed and the area shall be directly within
               control of NLNG.
         •     The Sterile Zone, bounded by the 10-6 risk contour, is an area in which other activities (i.e.
               other than LNG production) are allowed if the area is controlled. Such an area can include an
               industrial activity without access to their site by the general public. No housing and no
               extensive office facilities facilitating large gatherings of people are allowed.

         The safety and sterile zones as indicated in Figure 2.6 extend beyond the zones identified for the
         5-train operation. The safety zone no longer broadly coincides with the current site boundary
         fence, but will overlie land where NLNG will not allow other than oil & gas production-related

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         •    (parts of) the (for the public accessible) roads north and south-west of the fenced site
         •    an undeveloped swamp with a natural vegetation, east and south-east of the roundabout near
              the main entrance gate; this land is currently Mobil-leased land (see also Map 1)

         Access control over the safety zone will be enforced through fencing and (re)placement of gates
         on the roads.

         The newly-to-be-built Visitor’s Centre of NLNG, located south-west of the roundabout, will be
         situated just within the safety zone and will therefore be constructed such that it will be at least be
         as save as the safest office building on site. This building will be at a distance of at least 370 m
         from the trains 5/6.

         The current projected area for the sterile zone takes in areas that are outside the fenced plant site
         and outside NLNG’s leased land. Adequate control on housing will therefore be implemented and
         maintained for the lifecycle of the project in the swamp area south-east of the LNG site, where
         migrant settlement is not acceptable.

         The HHI construction camp on the SPDC site, just north-east of the LNG site, will be outside the
         safety zone but within the sterile zone. This camp will only include workers employed at Bonny
         Terminal. As such they are categorized as 'controlled personnel' and will be training in HSE
         awareness and subjected to routine emergency drills. The present location of the camp is
         therefore acceptable for SPDC and NLNG.

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             Figure 2.6. Plant layout for a full 6-train operation, showing various risk contours. Project elements of NLNGPlus are in
                       red, for NLNGSix in green. The “safety and sterile zones” east of the plant site are in striped green

2.5       NLNGSix construction and commissioning phase

         Construction of the sixth LNG train is expected to begin by mid/end 2004. The project will be
         completed by end 2007. The construction of the slug catcher will begin mid 2004, and will last till
         end 2005.

         Several different EPC(management) contractors will be involved in the construction activities, i.e.
         for the GTS-2/4 slug catcher, for the LNG train and for the tanks separately.

         During this time period a large number of temporary, short-term construction jobs will be created.
         These will range in duration from several months to two or three years. Labour and skill
         requirements include:

         •      Mechanical crafts (construction of machines, vessels, pipes, etc.), such as pipe fitters,
                certified pipe welders (for carbon, stainless, nickel), riggers, mechanics, foreman, semi-skilled
         •      Civil (erection of structures, tanks, industrial and non-industrial buildings), such as
                formworkers, carpenters, rebar workers, concreters, surveyors, structural steel erecters, non-
                industrial builders, foreman, semi-skilled labourers
         •      Electrical and instrumentation, such as cable pullers, electrical technicians, instrumentation
                technicians, foreman, semi-skilled labourers
         •      Cross-functional support, including insulators and sheet metal workers, painters,
                scaffolders, site preparation, ground Improvement, temporary facility operators, heavy lifting,
                crane operators, construction office, foreman
         •      Other labour such as security guards

         Preliminary estimates of jobs at peak construction demand on the Island are given in Table 2.4.
         The actual number of positions available in part depends upon the number of work-hours and
         rotations cycles instituted by construction contractors. Nigerian labour for train 6 is expected to
         increase during the ‘major civil works (August 2004 - July 2005) to about 4000. ‘During the ‘major
         mechanical works’ (May 2005 – November 2006) the overall workforce for train 6 will peak at
         around 4500 (including indirect). The Nigerian content will be at least 84% of all man-hours
         worked on site (see also Section 2.3.4). For the construction of the slug catcher the peak will in at
         650 workers in January-March 2005.

         The total number of Nigerian workers will not change much in the coming years, as many workers
         now active for the Plus project may also find a job in the Six project. However, as a consequence
         of temporal changes in the need for specific skills, major shifts in employed people will occur.

         The space and temporary facilities for all construction activities will be contained within the
         existing area leased by NLNG and the additional (for the Plus project newly acquired but
         temporary) lay-down along the eastern perimeter of the site (see Figures 2.6). Details on the
         location of the camps and residential area are presented in Table 2.4. Further details on project
         “hazards” and issues relevant for the impact assessment of the construction phase are presented
         in Table 2.4. These are grouped under the headings “resources” needed for the construction and
         “discharges” as a consequence of the construction activities. Where possible and relevant further
         details are provided which are necessary in the following chapters as input for this ESHA.

         Specific aspects associated with Commissioning - the time for commissioning and start-up is a
         couple of weeks – are emissions and flaring. Typically some flaring would occur during defrosting
         and (pre-)cool down of the cold end and achieving on spec gas from the acid gas removal unit
         (warm end start-up). The latter is minimized in train 6, as there is a special line between Trains 4,
         5 and 6 after the acid gas removal unit, to the Trains 1-3 feed gas header. This is for purpose
         done to minimize flaring. Hence, only some gas that cannot be evacuated to Train 3 for reuse has

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         to be flared. Quantities can only be guestimated at this moment. The best guess for flare losses
         during commissioning and start-up amounts to 66 kt.

         After completion of the construction, all (temporary) lay down and construction areas will be
         decommissioned, as well as the camp for the Nigerian workers. The decommissioning of the
         camps and construction areas and their future destination will become subject to a separate

             Table 2.4: Hazards and Issues list for the Construction Phase

              No    Hazard                                         Description and additional information

              1     Space required permanently
                                                                   Only the lease area currently in use by NLNG (see also Map 1) will be used.
                                                                   No additional land will be required, as also corresponded with the Federal
                                                                   Ministry of Environment. The 6th train will be construction east of the Plus
              1.1   LNG Plant and Process Facilities
                                                                   project (see Figure 2.7).The slug catcher will be constructed just north of
                                                                   the 3rd LNG train. Offices of the NLNG Construction team (ConTeam) will be
                                                                   moved mid 2003 to the temporary construction/lay-down area E of the site.
                                                                   Pipelines supplying LNG plant and cabling to services.
              1.2   Cabling and pipelines
                                                                   Access roads to NLNG plant site and around perimeter. Road along the east
              1.3    Roads outside current plot
                                                                   side has been shifted in mid 2003 around the future location of train 6.
              1.4   LNG Loading /Bunker fuel loading jetty         Jetty area including exclusion zone around jetty and berthing area.
                                                                   Marine offloading facility (MOF) is located at the NW corner of the site. This
              1.5   Marine off loading jetty
                                                                   is a temporary facility meant for the construction period only.
                    Contractor (EPC) camp adjacent to NLNG         Contractor camp is located in the north-east corner of the residential area
                    Residential Area                               and has temporary housing and other facilities.
              2     Space required temporarily
                                                                   Third Country Nationals (TCN) camp is located within the new
                                                                   construction/lay-down area east of the site. Nigerian Labour camp is
                                                                   situated NE of the residential area along the Camp Road, some 2.5 km from
              2.1   Contractor camp(s) and facilities
                                                                   site. Camp is meant for 5000 Nigerian; remaining 3000 seek local
                                                                   See also Map 1.
                                                                   Construction and lay-down areas currently include the existing cleared area
                                                                   on SPDC leased land east of NLNG site plus (sub)contractor area to the
                                                                   south of the plant site towards the Mobil area; see Map 1. Offices and
                                                                   workshops on NLNG lease and in lay-down area are needed for:
                                                                   · lay-down area – for equipment and materials lay-down
                    Lay-down / Contractor area (offices and
              2.2                                                  · vehicle maintenance shop
                                                                   · blasting and paint shop
                                                                   · fabrication shop/yard
                                                                   · insulation shop
                                                                   · concrete batching plant
                                                                   · asphalt plant and furnace
              3     Environmental resources - Water
                                                                   Fresh water source: water wells, treatment in water treatment plant, supply
                    LNG Plant and Associated Facilities Fresh      by tankers. 1.2 million litres fresh water may (depending on weather
                    Water Consumption                              conditions) be consumed per month for dust suppression during the dry
                    LNG Plant and Associated Facilities Other      Tankage hydrotesting will be done with treated sewage water that will be
                    Water Consumption                              discharged into Bonny River after usage.
              4     Environmental resources - food
                    Food and other consumables for construction    Catering services through accredited local companies are available to
                    workers and families.                          workforce for lunch and dinner. Individuals pay for the food.
                    Environmental resources - Materials and
                    LNG Plant, peripheral infrastructure and       Materials and equipment used for the construction of the LNG plant and
                    temporary works                                supporting infrastructure (including temporary buildings, fencing, etc).
              5.2   Chemicals used                                 No other chemicals than paint.

              6     Environmental resources-energy
                    Fuel consumption for contractor vehicles and   Diesel and petrol will be used. Storage on site in tankers for: 4 million litres
                    machinery.                                     of diesel and 100,000 litres of petrol. Monthly usage is 2,500,000 litres of

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           Table 2.4: Hazards and Issues list for the Construction Phase

            No      Hazard                                             Description and additional information
                                                                       diesel and 50,000 litres of petrol.

             7      Human resources - Labour
                                                                       Expected: 8000 Nigerian labourers, 1500 Third Country Nationals (TCNs),
            7.1     Number of construction labour and followers        700 experts (at peak). Assume worst case scenario of disbanding all staff
                                                                       after completion of train 6 and slug catcher.
             8      Discharges - Emissions
                                                                       Vehicle movements on unsealed areas (not just roads) in the NLNG plant
            8.1     Construction dust and emissions
                                                                       area, on lay-down areas and to/from the project area.
                                                                       Exhaust emissions from construction vehicles including water trucks. Refer
            8.2     Vehicle and incinerator emissions
                                                                       to fuel consumption to determine emissions.
             9      Discharges - Effluents
                                                                       Storm water drainage in place for site and camps. There are several
            9.1     Effluent from construction activity                discharge points into creeks and rivers. Discharge is monitored at regular
                                                                       Only tanks will be hydrotested (with treated sewage water0; hydrotest
            9.2     Cabling and pipelines
                                                                       water will be discharged.
                                                                       Stormwater run-off from catchment areas within residential areas is directly
                                                                       discharged to rivers and creeks. Sewage is treated by an activated sludge
            9.3     Residential areas and domestic effluents           process; discharge locations are Finima Creek and Bonny River. The
                                                                       treatment process is controlled; effluent quality is monitored on a regular
                                                                       Discharges from supply and engineering vessels for construction of
            9.4     Supply and engineering vessels
                                                                       equipment and transport.
            10      Discharges - Solid waste
                                                                       Timber waste is about 200 m3 per month - recycled or incinerated
                                                                       Metal waste is about 200 m3 per month - local scrap dealers
                    Construction waste
                                                                       Plastic/polythene waste is about 180 m3 per month - some recycled
                                                                       Biodegradable waste such as grass is about 250 m3 per month - local dumps
            10.2    Domestic waste                                     Domestic waste is about 2200 m3 per month - on-site incinerated

            10.3    Obsolete chemicals                                 Chemicals no longer required for use or spent. Include waste oils etc.

            11      Discharges - Noise
                                                                       Sound energy from construction activities - only during daytime –
            11.1    Construction noise
                                                                       intermittent and pulse-type
                                                                       Sound energy from transport/traffic associated with construction activities -
            11.2    Traffic noise                                      only during daytime. Workers are transported by man-carriers and busses
                                                                       from and to camps to constructions site(s).
            11.3    Residential                                        Sound energy from residential areas associated with construction workforce.

            12      Discharges - Light

            12.1    Construction lighting                              Light sources associated with construction areas (including lay-down areas).
                                                                       Light sources associated with marine operations associated with
            12.2    Marine operations
                                                                       construction activities (transport).
            12.3    Residential areas                                  Light sources associated with construction areas

            13      Incidents

            13.1    Spills of fuel, chemicals                          Amount and potential locations for spills of fuels.

            14      Decommissioning of camps

            14.1    EPC Contractor camp in Residential Area            Camp will be decommissioned after completion of train 6 and slug catcher

            14.2    Nigerian workers camps and facilities              Camp will be decommissioned after completion of train 6 and slug catcher
                    Temporary lay-down area E of site with
           14.3                                                          Camp will be decommissioned after completion of train 6 and slug catcher
                    offices, workshops and TCN camp
           Note: For construction activities a special incinerator will be used for burnable construction waste, similar to the earlier NLNG projects.
                 Although the design of this incinerator is such that the emissions fully comply with the applicable standards, the irregular usage
                 of this incinerator does not allow to describe these emissions in a quantified manner. However, as these emissions are a feature
                 that continues since all earlier projects, they are already included in the air quality measurements around the site, as presented
                 in Table 3.4 and Appendix 11. The same applies to emissions from the use of diesel and petrol during construction activities.

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2.6      NLNGSix operations phase

         Although the NLNGSix project is a stand-alone project and the associated ESHA process is
         aiming for formal approval for a single - the sixth - train, the baseline situation for this ESHA does
         include the operation of trains 1-5. As a consequence, the potential impacts of the sixth train are
         to be superimposed on the existing baseline and, hence, the potential impact of the other trains.
         This means that the scope of this ESHA is not limited the sixth train, but looks at all hazards,
         issues and potential effects caused by the operation of the full 6-train LNG plant.

         “Hazards” and issues relevant for the operations phase are presented in Table 2.5. These are
         grouped under the headings “resources” needed for the operations and “discharges” as a
         consequence of the production activities. Where possible and relevant further details are provided
         which are necessary in the following chapters as input for the ESHA.

         The number of permanent jobs at the NLNG site with 6 LNG trains in operations is estimated at
         approximately 100 expatriates and 530 Nigerians. A permanent NLNG Residential Area (RA) is
         situated on the southern coast of Bonny Island, to provide accommodation for the workforce at
         the plant (see Map 1). This existing residential area will accommodate all current and additional
         NLNG plant technical staff, the non-technical managerial and senior support staff and their
         families. It will also provide comprehensive community facilities required to sustain a population of
         NLNG employees and their families after project completion. All RA utilities and services,
         including electricity and water supplies, sewage collection and treatment and solid waste disposal
         are all to be provided from the LNG plant facilities. The site is a leased area of around 200
         hectares, located about four kilometres south-east of the LNG plant site. It is bounded by an
         access road to the new Finima village on the north and the Finima Nature Park (see Map 1).

             Table 2.5: Hazards and Issues list for the Operations Phase

              No    Hazard                                      Description and additional information

              15    Space required permanently

             15.1   Lease area for plant and residential area   No change
                                                                Marine operations safety zones and the berth areas for the tankers.
                                                                LNG: 350 ships per year
                                                                LPG: 76 ships per year
                                                                Condensate: 39 movements per year

             15.2   Marine operations                           Berth times:
                                                                LNG: ~14 hours loading, 22 hours on berth
                                                                LPG: ~11 hours loading, 19-20 hours on berth
                                                                Condensate: ~14 hours loading, 23 hours on berth

                                                                7 tugs for tugging, piloting, berthing, fire fighting and spill response
                                                                Contour exceeds current lease area at several locations; see Appendix 12.
             15.3   10-5 risk contour                           Access control over the safety zone will be enforced through fencing and
                                                                (re)placement of gates on the roads.
                                                                Contour exceeds current lease area at several locations; see Appendix 12.
                                                                Sterile zone restricting public risk exposure (less than 1 x 10-6) during
             15.4   10-6 risk contour
                                                                normal operations - requires control of land to ensure that no permanent
                                                                habitation or buildings that encourage gathering of groups of people.
                                                                Several roads are owned by NLNG and have been developed as part of
                                                                earlier Projects. There is a small modification to the road east of plant due
             15.5   Roads
                                                                to minor extra space requirement for Train 6. Roads inside 10-5 risk contour
                                                                are within the controlled area.
                                                                Regular (annual or bi-annual) maintenance dredging of channel and turning
             15.6   Maintenance dredging
                                                                basin. Not part of this Project.
              16    Environmental resources - water
                                                                Current (3-train) water extraction at water wells is 30,000 tonnes per day;
                                                                this will not increase during 4-6 train operation, as trains 4-6 will be air
                                                                cooled. Extracted water is primarily used for cooling of trains 1-3. Water
             16.1   LNG Plant and Facilities
                                                                wells are located several kilometres north of the LNG site. Potable water
                                                                production (for plant, RA and communities) per day is at 3,500 tonnes.
                                                                NLNG supplies >300 tonnes/day by tanker to communities.

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           Table 2.5: Hazards and Issues list for the Operations Phase

            No     Hazard                                           Description and additional information

            16.2   Marine base and residential areas                see 16.1

            16.3   Community potable water supply                   see 16.1
                   Environmental resources - Materials and
                                                                    Chemical consumption in normal plant operation. Inhibitor/detergent used
                                                                    for treatment of cooling water. Salt (solid) for low conc. Sodium
                                                                    hypochlorite disinfectant production in water treatment plant. Neutralite
                                                                    (solid) to provide Ca and Mg in drinking water. Sodium hypochlorite (liquid)
                                                                    as disinfectant in biotreater. Hydrochloric acid (liquid) for regeneration of
                                                                    the demineralisation unit. Caustic (solid) for regeneration of the
                                                                    demineralisation unit. DEA/MDEA (liquid) for CO2 removal. Various types of
                   Materials for LNG Plant and Facilities
            17.1                                                    oil for rotating equipment. Detergent wash (liquid) for gas turbine cleaning.
                                                                    Flocculants for compacting in filtration processes. Antifoam for U1100. All
                                                                    are stored in a chemical warehouse, combustibles and aggressive chemicals
                                                                    in a rainshed, plus storage in containers until realisation of the Train 6
                                                                    project. Warehouse is bunded and covered, with spillage collection pits
                                                                    (either local pits for specific situations (e.g. DEA) or for collection of
                                                                    plant/rainwater via the AOC/COC collection basins before discharge into the
                                                                    Bonny River.
            18     Environmental resources - Energy
                                                                    Energy for plant and RA.
            18.1   Energy usage by LNG plant and transport          Energy (gas) consumption 3-train operation is 1,584 ktonnes/year
                                                                    Energy (gas) consumption 6 -train operation: is 4,725 ktonnes/year
            19     Human resources - Labour
                                                                    Number of NLNG employees for a 6-train operation this will be 97 expats
            19.1   Operational work and followers
                                                                    and 528 Nigerians with their families.
            20     Discharges - Emissions
                                                                    Dust from vehicle movements on unsealed areas.
            20.1   Traffic dusts and exhausts
                                                                    Vehicle exhaust emissions (see 18.1 for fuel consumed).
                                                                    Various emissions from power generation, acid gas incinerator, waste
                                                                    The frame-7 gas turbines for train 6 will have dry low-NOx burners (DLN)
                                                                    and the frame-6 power generators non-DLN. This is to satisfy the
                                                                    flexibility requirements for power management of the whole LNG plant.
                                                                    However, once the utilities are in place for train 6 (about 6 months before
                                                                    the turbines are started up (on current estimates around October 2006),
                                                                    trains 4/5 gas turbines can have DLN and these will be retrofitted.
                   Plant and facilities emissions (including        For Base and Expansion: 130 m stack for 3 flares + 1 spare
                   baseload flaring associated with pilot, purge)   For all trains: 60 m stack for 3 liquid burners + 1 operational flare.
                                                                    For Plus and Six: 130 m stack for 2 flares+ 1 spare.
                                                                    Vent: 1 stack
                                                                    Flaring when a warm LNG carrier comes to the jetty (about every 3 weeks):
                                                                    the standard design is that the inert in the ship is first displaced by
                                                                    hydrocarbon, during that period the "boil-off" is routed to flare. This usually
                                                                    takes a couple of hours Once it is confirmed that the ship is inert free, the
                                                                    cooldown can start (takes about 24 hours) and during this period the vapour
                                                                    return lines are connected to the boil-off gas recovery system
                                                                    Detailed quantities and qualities of emissions are provided in Appendix 11.
                                                                    Exhaust emissions from the ships.
            20.3   Marine operations
                                                                    Detailed quantities and qualities of emissions are provided in Appendix 11.
                                                                    Exhaust emissions from the operation of the waste incinerator.
            20.4   Waste Incinerator Emissions
                                                                    Detailed quantities and qualities of emissions are provided in Appendix 11.
            21     Discharges - Effluents
                                                                    Drain systems on site:
                                                                    Entirely Oil Free (EOF) water: directly via drains to creek north of plant and
                                                                    to sea; see also section 3.1.4.
                                                                    Accidentally Oil Contaminated (AOC) water: drained to collection basin,
                                                                    where oil content is checked. Concentration <15 mg/l then discharge via
                                                                    EOF system. Concentration >15 mg/l then discharge into COC system.
            21.1   Operational plant effluents
                                                                    Continuously Oil Contaminated (COC) water: discharge into (bio)treatment
                                                                    Quantities of EOF and AOC discharges are not quantified on site.
                                                                    Cooling water blow down is discharged together with biotreater effluent into
                                                                    Bonny River.
                                                                    Detailed quantities and qualities of effluents are provided in Section 3.1.4.
                                                                    RA sewage and LNG plant sewage is discharged into the biotreatment plant
                   Domestic sewer system (plant and residential
            21.2                                                    on site Discharge from treatment unit into the sea is 50-80 m3 /h. Discharge
                                                                    point: about 50 m from shoreline between two jetties. Detailed quantities

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             Table 2.5: Hazards and Issues list for the Operations Phase

              No    Hazard                                         Description and additional information
                                                                   and qualities of effluents are provided in Section 3.1.4.

                                                                   Ballast discharge, bilge water, treated sewage and deck wash.
             21.3   Marine operations                              This discharge will be dealt with in the ESHA for the "Cannel Deepening and
                                                                   Marine Operations".
              22    Discharges - solid waste

             22.1   All types of solid industrial wastes           Amount and types of wastes, disposal routes and treatment; see 22.2.
                                                                   Up to and including NLNGPlus: 750 tonnes/y; NLNGSix will be <100
                                                                   tonnes/y. Paper wood and canteen waste from LNG plant go to incinerator
                                                                   (makes up 5-10% of incinerator feed). Waste from RA - waste segregated
                                                                   into combustible (>80%) and non-combustible (plastics, glass, metals) and
                                                                   biodegradable. By 2004, a dedicated waste yard will be used for
                                                                   segregation, cleaning and temporary storage of waste from train 6. It will be
             22.2   Domestic waste
                                                                   partially covered and with dedicated impervious base layer draining to a pit.
                                                                   Disposal route for each type of waste: All iron-based waste is recycled (incl.
                                                                   drums), rubber is recycled, waste oil is either incinerated internally (no
                                                                   waste heat) or used /burnt elsewhere (SPDC) including waste heat use.
                                                                   Quantities of wastes: 600 tonnes/y solid combustible waste (80% RA
                                                                   origin) is incinerated. 200 tonnes/y is disposed off Bonny Island.
             22.3   Solid waste from ships                         Part of waste mentioned in 22.2
                                                                   For amount and types, disposal route, treatment and characterisation see
                                                                   Chemical characterisation of incinerator residues: 12% Fe, 17% Ca, 1.5%
             22.4   Incinerator residue                            other alkali metals, 5% other metals. Remaining percentage ( 65%) mainly
                                                                   carbon and siliceous materials which cannot be broken down with an
                                                                   HNO3/HCl mixture. Incinerators residues amount to approx. 1-1.5 m3 per
                                                                   week and are stored for later processing.
              23    Discharges - Noise

             23.1   LNG plant site operational noise               Operational noise - see Appendix 10.

             23.2   Residential area noise                         RA noise - see Appendix 10.

             23.3   Traffic noise                                  Traffic noise - see Appendix 10.

              24    Discharges - Heat
                                                                   Heat generated from operation of cooling fans.
                                                                   Three cooling towers - one per train for 4, 5 and 6.
                                                                   Almost nil heating from cooling fans in trains 1,2 and 3.
             24.1   Heat from cooling fans                         There is an effect on microclimate for Plus and Six in heat emission from
                                                                   cooling towers - but cloud is emitted rapidly to the sky and dissipated
                                                                   rapidly. Heat transfer per cooling tower is 240MW. For the three trains this
                                                                   amounts to 720Mw in total.
              25    Discharges - Light

             25.1   LNG Plant site light                           Types, number, hours of operation. Not defined.

             25.2   Residential                                    Types, number, hours of operation. Not defined.

             25.3   Marine operations                              Types, number, hours of operation. Not defined.

             25.4   Flare light (all situations)                   Types, number, hours of operation. Not defined.

              26    Incidents

             26.1   Emergency venting                              Venting of pipeline and slugcatcher to atmosphere from terminal vents.
                                                                   Amount of flaring above base load due to emergencies. Estimated flaring
                                                                   amounts for total plant (with train 6 additional) based on predicted
             26.2   Flare emissions (emergency flaring)            performance and historical trip info. Estimated 33 kTN/y, target <17 kTN/y
                                                                   for whole plant (up to + including NLNGPlus). Train 6 estimate 6kTN/y
                    Fire water system discharges during            Fire water disharges (non-continuous) - discharge through the noraml
                    fire/explosion.                                drainage systems.
                    Spills from LNG, LPG, condensate, diesel and   Expected spill volumes (of liquids) = nil. If spilled, contained in custom
                    chemicals storage and process.                 designed spillage pits. Then COC and AOC.

15/06/2004                                                                        NLNGSix Environmental Impact Assessment, Volume 1

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