JX Nippon E&P (UK) case study: Loanan exploration well drilled West of Shetland

LR drills UK's first deep water, harsh environment well under the new OSD regulatory regime

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LR was able to mobilise a well planning team in a short period of time to deliver the UK's first deep water, harsh environment well to be drilled under the new OSD regulatory regime introduced following Macondo.

Contracting and procurement activities were undertaken in conjunction with detailed well planning which enabled the well to be spudded within 6 months of financial approval. While JX Nippon was nominated as Well Operator, well delivery was principally controlled and managed in accordance with the established LR systems and procedures.

The operational team comprised long term LR personnel with additional LR resources called on as required to supplement the core team. Although the selected drilling unit rig was new to the UK, rig acceptance, commissioning and mobilisation was conducted harmoniously. Drilling performance met expectations with full advantage being taken of the capabilities of the dual activity rig. The well was delivered efficiently with all key safety and performance targets being met.

– Richard Wilson, Head of HSE Manager, Drilling & Wells Quote marks right

Client: JX Nippon E&P (UK)
Location: UKCS – West of Shetland
Asset type: Well

Client Background

JX Nippon Exploration and Production UK, part of the JX Group headquartered in Tokyo, is involved in the Oil and Gas exploration and production business. Operating in fourteen countries around the world, with the UK (North Sea) being one of their core areas of operation.

Business challenge for the customer

JX Nippon required full well project management, site survey management and rig survey and inspection service, for their Loanan prospect; one of only a few exploration wells drilled in the UK in 2016, and only JX Nippon's second time as an Operator in the UK.

The Loanan prospect is located in approximately 2,305 feet of water in the West of Shetland basin, which has a "limited" operational weather window. It was the first time the rig had worked in UK waters and with a brand new crew.

The UK regulatory regime had changed, in response to EU guidelines, this was the first deepwater exploration well drilled in the UK under the new regime.

How Lloyd's Register helped

Lloyd's Register provided full project management support; managing the well design and planning, construction and drilling operations of the exploration well, preparing regulatory permits, emergency response arrangements and managing drilling operations, designing the site survey, selecting the site survey vessel, preparing the QAQC survey data and report, carrying out a shallow hazards assessment, shallow gas identification and providing Iris (our project support and data management tool), and rig positioning services.

The well design was based on a 'full hole design' with four casing strings being ran, with an 8-1/2" section drilled to evaluate the reservoir. However due to weaker formation strengths a 7" drilling liner was required, and a short 6" hole section was drilled prior to plug and abandonment operations.

A full condition survey was carried out by our Drilling Integrity Services team, in addition to well control and environmental work, a Blow Out Preventer (BOP) condition survey and acceptance, and provided deepwater awareness training.

Overcoming challenges

This was a challenging project, due to the difficult operating conditions. Many obstacles were predicted, encountered and overcome including; the offset wells had encountered location issues with boulders and strong sea currents. There were drilling issues with maintaining verticality, hole instability, tight hole and packing off, particularly in the 12 ¼" section, with more than one well requiring a sidetrack, and most sections required multiple bit runs. There was also the possibility of encountering high pressure dolerite sills in the deeper 8 ½" section.

Expertise applied

  • Wells project management
  • Drilling Integrity services
  • Survey & GeoEngineering

Results

  • Successfully complied with the new UK regulatory submission requirements, and ensured that a DECC inspection of the rig was supported adequately
  • Minimised the overall time the hole sections were open and no hole issues were encountered in any of the sections due the expertise and technologies applied.
  • The well was planned and executed in a short time frame to ensure the well was drilled during the optimal summer months.
  • The choice of a fit for purpose harsh environment drilling rig resulted in no WOW.
  • The exploration well was delivered with zero accidents.

Benefits

  • The well was delivered with zero accidents.
  • The well was delivered within +/- 5% of the AFE.
  • The well was drilled on target.