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Chapter 4 Project Development and Evaluation of Alternatives

80343_ESIA_ADD_chapter_div.indd 4 05/03/2014 11:16

SCP Expansion Project, Georgia Environmental and Social Impact Assessment Addendum

Draft for Disclosure (Amended)

TABLE OF CONTENTS

4 PROJECT DEVELOPMENT AND EVALUATION OF ALTERNATIVES .......... 4-1 4.1 Introduction ............................................................................................... 4-1 4.2 Development Concept Alternatives ........................................................... 4-1

4.2.1 Export Methods ........................................................................................... 4-1 4.2.2 Project Concept .......................................................................................... 4-1 4.2.3 Concept Selected for SCPX Project ............................................................ 4-5

4.3 48” Routing Alternatives ............................................................................ 4-6 4.3.1 Proposed Additional Eastern Section of Pipeline (KP56.6-62.3) .................. 4-6 4.3.2 Proposed Additional Western Section of Pipeline (PRMS KP0-2.5) ............ 4-9

4.4 Pipeline and Road Crossing Alternatives ................................................ 4-12 4.4.1 Road Crossings ........................................................................................ 4-12 4.4.2 Pipeline Crossings .................................................................................... 4-12

4.5 Pigging Station Location ......................................................................... 4-12 4.6 Access Roads ......................................................................................... 4-12

4.6.1 Permanent Access Road to Pigging Station .............................................. 4-12 4.6.2 Temporary Construction Access Roads .................................................... 4-12

4.7 Conclusion .............................................................................................. 4-12

Tables Table 4-1: Comparison of Potential Environmental and Social Impacts of SCPX 56”-,

48”- and 42”-Diameter Pipeline Options ........................................................... 4-4 Table 4-2: Comparison of Potential Impacts of SCPX 56”, 48” And 42”-Diameter

Pipeline Options ............................................................................................... 4-5 Table 4-3: Summary of Route Options for Additional Western Section of Pipeline 4-11

Figures Figure 4-1: Schematic Showing a Comparison of the 56”-, 48”- and 42”-Diameter

Pipelines .......................................................................................................... 4-2 Figure 4-2: Selected 48” Option .............................................................................. 4-6 Figure 4-3: Route Options for the Proposed Additional Eastern Section of Pipeline4-8 Figure 4-4: Route Options for Proposed Additional Western Section of Pipeline .. 4-10

Project Development and Evaluation of Alternatives i

SCP Expansion Project, Georgia

Environmental and Social Impact Assessment Addendum Draft for Disclosure (Amended)

4 PROJECT DEVELOPMENT AND EVALUATION OF ALTERNATIVES

4.1 Introduction This chapter describes the elements of the proposed updated design of the SCPX Project subject to the ESIA Addendum, for which alternatives were assessed, and explains the reasons why the particular options presented in Chapter 5 were adopted. The alternatives are:

· The development concept and the diameter of the pipeline · The pipeline route · The type of river, pipeline and road crossings · The location of the facilities.

Alternative options are generally evaluated with consideration given to environmental and social (E&S) and health and safety (H&S) potential impacts, technical feasibility and commercial implications. Where kilometre points (KPs) are mentioned to describe the location of certain features, these denote the nearest kilometre point on the 48” pipeline loop. Where reference is made to the location of CSG2 and PRMS, where there is no new SCPX pipeline, the KP denotes the nearest kilometre point on the SCP pipeline.

4.2 Development Concept Alternatives

4.2.1 Export Methods The SCPX Final ESIA discussed alternative methods for exporting gas from the Shah Deniz field. Its conclusion, that gas export by pipeline is the most efficient and economic option for transport, is still valid.

4.2.2 Project Concept The existing 42”-diameter SCP pipeline has been transporting gas from the Sangachal terminal in Azerbaijan for 690km to the border of Georgia and Turkey since 2006, with a system design capacity of 7.41 bcma (billion cubic metres annually). Further development of the Shah Deniz reservoir is planned, with the additional gas produced significantly exceeding the current capacity of the SCP. A number of different concepts combining variations of pipeline diameter, pipeline loop length, and compression power can achieve the required flow rate. Increasing the diameter of the pipeline reduces the rate at which the gas pressure in the pipeline diminishes, so less compression power is needed as the pipeline diameter increases. Various options to expand the existing SCP system, to incorporate the additional gas from the Shah Deniz FFD, were evaluated. The evaluation process was carried out by a multidisciplinary team that took account of the relative importance of H&S, E&S, technical and commercial considerations. The 56”-diameter pipeline partial pipeline loop for some distance in Azerbaijan and Georgia and two compressor stations in Georgia was selected and is the subject of the SCPX Final ESIA. A subsequent review of the pipeline design undertaken after the SCPX Final ESIA received consent has identified a 48”-diameter pipeline as a further option, which is the focus of this chapter. This refinement in the Project design (described in Chapter 5 Project Description,

Project Development and Evaluation of Alternatives 4-1



of the ESIA Addendum) has been evaluated from H&S, E&S, technical and commercial perspectives.

42”-, 48”- and 56”-diameter options This section assesses the 48”-diameter pipeline against the 56” option and the 42” option as described in the SCPX Final ESIA. In order to decrease the pipeline diameter to 48” and achieve the required flow rate of an additional 16 bcma, either the length of pipeline or the compression power needs to be increased. Reducing the pipeline diameter with no additional pipeline would require an increase of the compression requirement from the 56” option (66MW at each compressor station) to a level approximately equal to the 42” pipeline (80MW at the first compressor station and 70MW at the second). This would entail a proportional further increase in Project greenhouse gas emissions. In addition, the compressor station design had sufficiently progressed to a level which would mean changes would be detrimental to the Project construction schedule. Maintaining the current compression power requirements was therefore retained and extension to the pipeline route selected as the mechanism of achieving the required flow rate. The 48”-diameter option therefore requires an additional 6km extension to the pipeline in Georgia west of Marneuli (the eastern section of pipeline) and an additional 34km of pipeline in Azerbaijan from KP23 to KP57 (see Box 1). As the capacity of the compressor stations has remained unchanged for the 48” pipeline, the assessment of compressor station alternatives within Chapter 4 of the SCPX Final ESIA therefore remains unchanged. Figure 4-1 illustrates a schematic comparing the three pipeline diameter options (each with two compressor stations).

Figure 4-1: Schematic Showing a Comparison of the 56”-, 48”- and 42”-Diameter Pipelines




Box 1: Pressure Comparison between Three Pipeline Options

1. Compressed gas enters the pipeline at Sangachal terminal at 90 barg when

operating at the design flow rate (i.e. +16bcma).

2. For the 48” and 56” systems, all the gas flows initially through a single 42”-diameter pipeline, whereas the 42” system has two pipelines. Therefore, the initial frictional losses are higher in the 48” and 56” systems and the rate of pressure drop is faster.

3. The 48” loop commences at a crossover from the 42”, and the gas redistributes into the two pipelines.

4. The 56” loop commences at a crossover from the 42”, and the gas redistributes into the two pipelines.

5. The twin 42” frictional losses are higher than the 48” & 42” or 56” and 42” systems and the rate of pressure drop is fastest (shown as the steepest gradient on the graph).

6. Compression Station 1 suction pressure is approximately 40 barg for the 42” system, and 45 barg for the 48” and 56” systems. The 42” system requires 4 operating compressors whereas the 48” and 56” require only 3.

7. Compressed gas leaves Compression Station 1 at 90 barg at the design flow rate.

8. The frictional losses and pressure drop in the 56” and 42” pipeline in parallel are less than that for the other systems.

9. The frictional losses and pressure drop in the 48” and 42” pipeline are higher than the 56” and 42”, but less than a dual 42” system.

10. Compression Station 2 suction pressure is 40 barg for the 42”system, and 45 barg for the 48” and 56” systems. The 42” system requires 4 operating compressors whereas the 48” and 56” require only 3.




Technically the 56” is the most challenging to construct, as the pipe needs careful handling and lifting during construction and involves the most complex trenchless crossing techniques (e.g. micro-tunnelling). Commercially, the 48”-diameter pipeline has a lower capital cost than the 56”-diameter pipeline and represents the optimum balance between meeting the immediate gas transport requirements, i.e. an additional 16 bcma, while retaining the capability for future expansion.

From a health and safety perspective, the 48” option uses less complex handling operations than the 56” option, and combined with the decrease in traffic movements owing to an increase in the number of pipe sections that can be transported on one truck, this decreases the overall potential construction health and safety impacts compared with the 56” option. The 42”-diameter pipeline involves similar construction challenges to the 48” and a further reduction in traffic movements due to the shorter pipeline loop lengths. As described in Chapter 3, the screening exercise undertaken for the 42” and 56” options was undertaken for the 48” option. The environmental and social topics where during screening, there was a variation between the options across both Azerbaijan and Georgia, are shown in Table 4-1. It should be noted that the results are relative and should be interpreted independently for each discipline, with a value of 3 representing the highest potential impact and 1 the lowest.

Table 4-1: Comparison of Potential Environmental and Social Impacts of SCPX 56”-, 48”- and 42”-Diameter Pipeline Options

Topic 56” Option

48" Option 42" Option Comment

Protected areas 1 1 2 The 42” concept involved routing adjacent to the Gobustan Cultural Reserve and Buffer Zone. The shorter pipeline loops on the 56” and 48” option avoid this area.

Protected or endangered species

1 2 3

The highest density of Iris actuiloba (Azerbaijan Red Data Book) is found with the eastern section of the pipeline. The progressively longer loop lengths in this area from 56” to 48" to 42” increase the potentially affected area of Iris actuiloba habitat.

Environmentally sensitive areas 1 2 3

The progressively longer loop lengths at the eastern end of the pipeline for the 48” and 42” extend further into the semi-desert Gobustan area and several areas known as the Badlands, both of which contain fragile topsoil where reinstatement is more difficult. In addition, the 48”and 42” pipeline crosses the mud volcano area and the 42” pipeline crosses a further major river crossing with steep-sided banks.

Greenhouse gas and air emissions

2 2 3

Greenhouse gas and air emissions are highest with the 42” option due to the highest compression requirements and lower for both the 56” and 48” which have the same lower requirements




Topic 56”

Option 48"

Option 42" Option Comment

Community safety 3 1 2

The potential risks to community health and safety during the construction phase are decreased with the 48”-diameter pipeline due to the ability to carry more pipes per truck than the 56” concept and the associated reduced number of trucks required. The 42” pipeline has a longer length of pipeline and can carry three standard pipes per truck and greater numbers of truck movements over a larger distance; therefore, it has an intermediate potential risk.

Community disturbance 1 1 2

The potential impact from community disturbance at the compressor stations is lower with the 56” and 48” options due to the reduction in the numbers of compressors required.

Total 9 9 15 Other areas assessed for which there was determined to be no significant difference between the three options included freshwater resources, wastewater discharges, waste, cultural heritage, community health, economic resettlement and infrastructure quality.

Table 4-2 presents the overall comparative assessment of the 48”, 56” and 42” pipeline configurations.

Table 4-2: Comparison of Potential Impacts of SCPX 56”, 48” And 42”-Diameter Pipeline Options

Option Description Technical Commercial Health and Safety

Environmental and Social

48” Two compressor stations, minimum looping

Moderate Moderate Moderate Moderate


Higher Higher Higher Moderate


Lower Lower Lower Higher

4.2.3 Concept Selected for SCPX Project As described within the SCPX Final, ESIA two compressor stations and an expansion of the existing PRMS will be developed in Georgia. This will achieve the flow rate of +16bcma in the SCPX pipeline and a combined capacity of +23 bcma by maximising the use of the existing SCP pipeline. The selected option (Figure 4-2) is a 48” loop pipeline from a start point in Azerbaijan, some 23km from the Sangachal Terminal (at SCP KP23, Azerbaijan), to a point on the SCP pipeline approximately 63km inside the border with Georgia. In addition, a 2.5km pipeline loop will be added running from the PRMS to the Georgian/Turkish border, to connect to the TANAP and facilitate the export of gas to Europe (Section 4.3.2).




Figure 4-2: Selected 48” Option

4.3 48” Routing Alternatives The required extension of pipeline by 6km results in routing alternatives for the additional eastern section of pipeline (KP56.6-62.3). The proposed 2.5km pipeline loop from PRMS also presents several routing alternatives. These alternatives are discussed below. Routing of the Georgian section of the pipeline loop from the border with Azerbaijan to KP56.6 remains unaffected and is discussed in SCPX Final ESIA, Section 4.4. The consideration of route corridor options followed the same process as described in the SCPX Final ESIA with the Project’s preferred option being to route the additional sections of pipeline adjacent to the existing BTC/SCP pipeline right of way (ROW) where possible, taking account of known constraints. The BTC and SCP routes were identified following extensive engineering, environmental and social surveys and took into account an optimal secure border crossing from Georgia into Turkey. This has considerable environmental and social advantages over the establishment of a new corridor including:

· Partial overlap with a previously disturbed corridor reduces new land take and habitat disturbance

· Relationships have been established with the local communities · Some established access routes can be used minimising the need for new ones · Operational inspections can be confined to the same pipeline corridor.

Routing studies focused initially on the minimum safe separation distance of the SCPX ROW from the existing SCP/BTC or any other pipelines. Modelling studies (see Chapter 12 of the SCPX Final ESIA) determined that the minimum separation distance between the 56” SCPX pipeline and the BTC and SCP pipelines should generally be 20m. This separation distance has been maintained for the 48” pipeline (see Chapter 12). Following the definition of a proposed route, specialists and sub-consultants were commissioned and studies undertaken to identify the key constraints and identify and discuss various potential re-route options where key constraints such as cultural heritage was known.

4.3.1 Proposed Additional Eastern Section of Pipeline (KP56.6-62.3) The assessment of BTC/SCP corridor confirmed that the additional section of the SCPX pipeline could be accommodated adjacent to the existing SCP and BTC pipelines. There were no major environmental and social constraints identified on this proposed route, which was assessed in the original draft ESIA Addendum. However, subsequently, the identification of third party infrastructure, including a gas line and several water pipelines, required a review of part of the proposed additional eastern section of pipeline in the area north of Khaishi. Two alternatives were considered, a re-route to the north of the proposed route or a re-route to the south, on the other side of the BTC/SCP pipelines.. The initial pipeline route and routing options are shown in Figure 4-3. Both re-routes were of similar length, however the southern re-route required two additional crossings of the BTC and




SCP pipelines and was thus felt to be more technically challenging. In addition, the northern re-route option is further away from the village of Khaishi. Considering these technical constraints and the potential for lower environmental and social impacts due to further proximity from Khaishi, the northern route option was selected. This re-route is assessed in the amended draft ESIA Addendum.




Figure 4-3: Route Options for the Proposed Additional Eastern Section of Pipeline




4.3.2 Proposed Additional Western Section of Pipeline (PRMS KP0-2.5)

For the additional pipeline loop from PRMS to the Turkish border, the following route options were considered (see Figure 4-4):

· Option 1 (eastern route) · Option 2 (western route) · Option 3 (hybrid route).

A number of constraints were assessed from a technical and environmental and social perspective, which are summarised in Table 4-3. Owing to constraints associated with the Georgian border facilities, and to the objective of maintain all three pipelines within the same corridor, pipeline routing alternatives within a wider area were not considered further.




Figure 4-4: Route Options for Proposed Additional Western Section of Pipeline




Table 4-3: Summary of Route Options for Additional Western Section of Pipeline Option Technical Constraints Environmental and Social Constraints

1 East

Rocky outcrop at c. PRMS KP0.6 to the east, which will require a potential reduced ROW

· Re-route of access track leading to a communications tower required

· Deep gully crossing at c. PRMS KP1.7

· Orchosani Archaeological Site

· Orchosani Modern Cemetery Crossing

· Riparian woodland fragment containing Georgian Red List (GRL) species (High Mountain Oak, Quercus macranthera), high conservation value

2

West

· Requirement to re-route the access road to the existing Area 80 Facility

· Deep crossing of the SCP and BTC Pipelines with potential bedrock

· Deep gully crossing at c. PRMS KP1.7

· Potential cultural heritage sites



· Riparian woodland fragment - high conservation value

· Deciduous woodland patch at border - medium to high conservation value

3

Hybrid

· Narrow ROW past rocky outcrop to the east

· Re-route of access track leading to a communications tower required

· Deep crossing of the SCP and BTC Pipelines with potential bedrock

· Potential cultural heritage site



· Deciduous woodland patch at border - Medium to high conservation value

All three route options cross the large multi-component archaeological site (BPGA 15, Orchosani), which is within the border controlled area. The site is crossed by both the BTC and SCP pipeline routes and was crossed using an open-cut technique by BTC and a trenchless technique, for part of the area, by the SCP construction. In addition, it is known from BTC/SCP construction that this site also contains modern Muslim burials. The full extent of the site is currently unknown; however, as there were no archaeological chance finds during the SCP trenchless crossing, this gives an indicative location which will be used in the planning of the SCPX crossing. SCPX will follow similar construction techniques to SCP in this area and trenchless crossing or other modified construction techniques will be used where practicable to avoid impacting the cemetery. (see Chapter 5). Option 3 (Hybrid) is the selected route option, as it is preferable from both a technical and environmental perspective. It avoids the deep gully crossing at c. PRMS KP1.7 and the high conservation value riparian woodland fragments, one of which contains Georgian Red List species. ROW narrowing at this area was considered to reduce impacts on the deciduous habitat at the border; however, this was not possible due to technical and constructability constraints associated with the tie-in to the TANAP connection. Relevant mitigations for the impact on the deciduous woodland patch are discussed in Chapter 10. The exact location of the final tie-in point with the TANAP connection will be determined via close cooperation during detailed design of both SCPX and TANAP.




4.4 Pipeline and Road Crossing Alternatives

4.4.1 Road Crossings The proposed additional eastern section of pipeline crosses paved roads at SCP KP58.6 and SCP KP61.7, which will be crossed using one of the following techniques:

· Open – cut. The trench is excavated across the road surface which is reinstated upon installation of the pipe

· Direct-burial pipe jack (carrier pipe). A carrier pipe is installed behind a protective shield using a combination of mining techniques and hydraulic jacks to drive the pipe forward. The excavated material is removed through the exposed end of the pipe. As each pipe progresses forward, another is welded on until the crossing is finished

· Micro-tunnelling. Sections of concrete carrier pipe are driven into the hole opened by a TBM by hydraulic jacks. Excavated material is removed via the exposed end of the carrier pipe. As each section of the concrete pipe progresses forward, another is connected behind it, until the hole reaches the far side of the crossing. After completion of the carrier pipe, the pipeline is installed.

4.4.2 Pipeline Crossings Pipeline crossing techniques available for Project use are discussed in Chapter 5, Project Description.

4.5 Pigging Station Location There is a requirement for the integrity of the new pipeline to be monitored periodically using a pipeline integrity gauge (pig). In Georgia, the pig will run from CSG1 to a pigging station that has been relocated from KP56.6 to the end of the 48” pipeline loop, at KP62.3. Two alternatives were considered for the location of the pigging station, a location approximately 500m east of the selected location (Figure 4-3) was considered inappropriate owing to its proximity to the village of Khaishi and adjacent road and railway infrastructure.

4.6 Access Roads

4.6.1 Permanent Access Road to Pigging Station The location of the new permanent access road to the pigging station is likely to involve the upgrade of an existing unmade track that runs from the main road parallel to the ROW and railway line. There are no environmental and social constraints associated with this area.

4.6.2 Temporary Construction Access Roads Temporary access is required to the construction ROW for the additional sections of pipeline. Access roads are expected to take advantage of existing roads and roads used during the construction of BTC/SCP pipelines. The proposed access routes are described in Chapter 5.

4.7 Conclusion This section has summarised some of the alternatives that have been reviewed as part of the proposed updates to the Project. The selected updates have been described in detail in Chapter 5. The selection of preferred solutions subject to the ESIA Addendum affects the overall environmental and social impacts of the SCPX Project that are assessed in Chapter 10 and Chapter 12.


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