IOG provides update on Southern North Sea dual hub development project
Tuesday, Jun 05, 2018
Independent Oil and Gas ('IOG'), the development and production focused Oil and Gas Company, has provided an operational update on the Thames Pipeline Intelligent Pigging and Offshore Surveys Programmes, both crucial parts of its Southern North Sea dual hub development project.

Highlights:

  • Three pipeline sections cut 60km offshore and retrieved to surface indicate that the pipeline is in extremely good condition.
  • Two successful pipeline pressure tests have confirmed pipeline integrity.
  • Initial 60km gauge pigging runs from Bacton to offshore tie-in point successfully executed.
  • Initial intelligent pigging run gathered insufficient data due to technical malfunction with the pig; second run required to complete data acquisition.
  • Four months of offshore Geophysical surveys, shallow seismic, external pipeline inspection surveys, and environmental and geotechnical surveys by Fugro vessel MV Galaxy now complete.
Intelligent Pigging Programme (IPP)

The IPP has involved the following key steps, with Subsea7 as diving support vessel provider, Rosen as pig supplier, operational management from ODE and engineering support from EnerMech.

Firstly, on 3 May, three 12 metre sections of the Thames pipeline were cut 60km offshore, just beyond the point where the Southwark gas field will tie in to the recommissioned 24-inch Thames export pipeline.  These were transported onshore and visual inspection showed them to be in extremely good condition, with very little evidence of corrosion or wall thickness degradation.  This was a significant first step in verifying the integrity of this gas pipeline, which was decommissioned in 2015.

To view an image of the Thames pipeline please use the following link:
http://www.rns-pdf.londonstockexchange.com/rns/2503Q_1-2018-6-4.pdf
A temporary subsea pig receiver was then installed at this 60km tie-in point and a successful pipeline pressure test was undertaken from the Bacton gas terminal to this receiver.  This provided significant further evidence of pipeline integrity.

Next, a cleaning and roundness gauging pigging run was successfully conducted from Bacton to the offshore tie-in point, where an offshore pig launcher was then installed.  This enabled the 60km intelligent pigging run from offshore to Bacton to be completed on 26 May.  Intelligent pigs are devices run through pipelines to assess pipeline wall thickness and to evaluate any evidence of corrosion.  On arrival, due to an apparent pig malfunction, it became evident that we had not collected sufficient data.  While the steps mentioned above give IOG's management very strong confidence in the pipeline's condition, in order to recommission this pipeline the Company nonetheless firmly requires a complete data set from an intelligent pigging inspection, so that all stakeholders including contractors and funders are fully satisfied as to its reuse.  IOG is therefore planning a second intelligent pigging run to complete data acquisition at the earliest opportunity, which is expected to be within weeks.

As a further step after the intelligent pig run, the pipeline was then successfully hydrotested with inhibited sea water for 24 hours to confirm integrity, and has now been suspended in a safe condition.  Hydrotesting involves elevating the water pressure in the pipeline for a sustained period and is another key step in pipeline validation.  The success of this test provides strong further evidence that the pipeline is fit for purpose for IOG's needs.

The need for a second intelligent pig run will inevitably have some impact on the project schedule.  IOG has advised the Oil and Gas Authority (OGA) of this requirement and will request a short extension on the FDP approval target date, which is currently the end of August 2018.  Subject to final pigging results, the pipeline will be ready for the full and safe recommissioning to export IOG's extensive Southern North Sea gas portfolio, which contains 303 BCF of 2P gas reserves across five proven fields, plus further development and appraisal assets.

Offshore Surveys Programme

Over January to May 2018 the Fugro MV Galaxy completed the various offshore surveys needed to support the development of the Blythe and Vulcan Satellites Hubs.  The work programme comprised geophysical surveys, shallow seismic of the four platform and five drill sites, general inspection surveys of the Thames pipeline, environmental surveys and geotechnical surveys.  Post survey work will entail data processing, analysis, interpretation and reporting, geotechnical laboratory testing and analysis of cores, environmental laboratory testing and analysis of samples and the integration of geophysical, geotechnical and environmental data and final reporting.  All of this acquired data is required for Field Development Plan approvals.

Photo - see caption

Andrew Hockey, CEO of IOG commented:

'The Intelligent Pigging Programme has so far provided extensive and valuable new information to the IOG team to support our plans to recommission the fully-owned Thames Pipeline and produce our Proven and Probable reserves of over 300 BCF safely into the Bacton gas terminal and the UK market.  We are very pleased with the two successful pressure tests, several pig runs in both directions through the line, and the excellent condition of the sections extracted to shore as shown in the attached images.

While this gives us even greater assurance on the pipeline's fitness for purpose, we do still require the intelligent pigging data acquisition to be fully and properly completed.  We are now fast-tracking plans to have this done as soon as possible, while our other project development workstreams continue in parallel to maintain our good momentum towards FDP approvals for this substantial UK gas project.  The successful completion of our four-month offshore survey programme, which has provided a wealth of required data, is also a key step in that regard.

Finally, we are pleased to have progressed both of our 2018 offshore operational programmes with no safety or Lost Time Incidents.'

For more information, please visit: http://www.independentoilandgas.com

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