OVERVIEW

AGR’s Well Management was contracted to support the abandonment of a series of subsea wells. The client needed to look at the most effective method of carrying out the abandonment campaign and ensure that all of
the Australian regulator requirements were met.

THE CHALLENGE

In order to source and contract a rig for the operations, the following needed to be considered:

  • A light intervention vessel could do some of the work but it would need a Mobile Offshore Drilling Unit (MODU) to carry out other areas
  • A jack-up could carry out all of the work or the remainder of the work that the intervention vessel could not complete. However a jack-up could have a higher risk of waiting on weather as it moved between
    the wells
  • A semi-submersible could carry out all of the work or the remainder of the work that the intervention vessel could not complete. The semi-sumbersible could kedge between wellheads so would not be affected by the weather, however there would be an additional cost that may not be offset by the possible time saved
  • The abandonment had to comply to internationally recognised standards for zonal isolation etc

KEY ENABLERS DELIVERED BY iQx™

  • P1™ output a detailed analysis of the time and cost for the many permutations of intervention vessel, jack-up and semisubmersible
  • The probabilistic analysis took into account weather conditions, exchange rates, and rig rates among other elements to deliver a simple comparison and allow the client to make an informed choice on the best vessel for the operations
  • The AGR Well Delivery Process is traditionally used for drilling wells, however the process is just as applicable to preparing for a well abandonment. This gave the client an auditable and measurable method that AGR would utilise for designing and executing the well abandonment.