OBEN GAS DEVELOPMENT PROJECT

Chapter Two Project Justification
referred to as Blow out preventer (BOP) with surface safety valves. This equipment shall be used to
close in a well at the slightest detection of formation fluid ingress/flow into the well bore (mud system).
This equipment shall be tested regularly to ensure proper functionality.
In addition, there would be increased land and air logistics during the proposed drilling operations, since
materials and workers would be moved to site due to operations demand.
2.9 Flowline Contruction
The activities to be undertaken will include:
• Land-take for lay down area (for construction equipment);
• Site Preparation;
• Flushing of the existing flowlines;
• Excavation and removal of old flowlines;
• Site Construction (Welding and Non-Destructive Testing [Radiography]);
• Pressure Testing of the new lines;
• Pipe laying and tie-in;
• Commissioning of the new flowlines;
• Backfilling;
• Operations/Maintenance;
2.9.1 Flowline Construction
Flowline construction methods differ depending on the geographical area, terrain, environment and third
party presence. In all cases, the construction of the flowlines shall comply with codes and standards
imposed by the law and standards organizations. The design for the proposed flowlines shall be in
accordance with applicable national, international, industry and Shell standards.
2.9.2 Land-take
There shall be no route survey of the flowlines since the proposed routes are on existing SPDC Rightof-Way
(ROW). The existing 15 m corridor of the ROW should be adequate for the flowlines activities.
However, the construction activities may require about 80 m 2 additional land within SPDC acquired
area, as temporary lay down area for construction equipment.
2.9.3 Site Preparation
A total area of ~800 m 2 would be required for lay down of construction equipment and shall be manually
cleared of any grown vegetation. This will comprise ~720 m 2 on the existing ROW and the additional 80
m 2 . The clearing activity will be carried out by community members (~10 persons). The vegetation
cuttings shall be left in the field and allowed to decompose.
2.9.4 Flushing of Existing Pipeline
The existing Oben wells shall be shut-in to allow for flushing of the entire length of the flowlines. Water
pump shall be used to provide the pressure necessary to flush the lines from the well head to the gas
plant. The wastewater shall be disposed via the saver pit. Vacuum trucks shall be used to evacuate the
water from the saver pit to Oben flowstation, where it will be pumped into the trunkline to Forcados
Terminal for handling.
2.9.5 Excavation and removal of old flowlines
The excavation shall be carried out manually. The excavated section shall be manually freed of roots,
stones, or other hard objects that may damage the pipe or its coatings. The maximum width of the
excavated section shall be 3 m with a minimum depth of 1m
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