Independent Oil and Gas (IOG) has completed intelligent pigging and offshore survey programmes on the Thames pipeline, part of its Southern North Sea dual hub development project.
IOG acquired the Thames gas pipeline in April 2017, from Perenco UK, Tullow Oil and Centrica, to provide the proposed export route for its Southern North Sea assets.
The company undertook an intelligent pigging inspection (IPP) to ensure the pipeline’s integrity for safe re-use, and according to its latest update the three pipeline sections that were cut 60 kilometers offshore and retrieved to surface indicate that the pipeline is in good condition.
The three 12 meter sections of the Thames pipeline were cut 60 kilometers 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 good condition, with very little evidence of corrosion or wall thickness degradation.
This was the first step in verifying the integrity of this gas pipeline, which was decommissioned in 2015.
During the inspection work the company also experienced the malfunction of a pig, which will lead to a second inspection to complete data set from an intelligent pigging inspection.
According to IOG, the second inspection 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 recommissioning to export IOG’s Southern North Sea gas portfolio, which contains 303 BCF of 2P gas reserves across five proven fields, plus further development and appraisal assets.
Furthermore, IOG informed taht 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.
Andrew Hockey, CEO of IOG said: “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.
“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 work streams 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.“