Our well kill experts provided multiphase flow modelling and well control supervision throughout the entire project.
On August 21st 2009, the Montara H1 ST-1 well blew out underneath the cantilevered derrick of the jack-up rig West Atlas. The Montara field consists of a 4 well slot un-manned wellhead platform, located 675 kilometers west of Darwin, Australia, in the south part of Timor Sea. The water depth is ~80 m.
The production well was completed with a horizontal section into the reservoir with a 9 ⅝” casing set at total depth. The well was suspended for 5 months. In August 2009, the crew removed a pressure containing corrosion cap set inside the casing in preparation for installation of the BOP. The blowout started with a flow of condensate from a thin oil reservoir zone, followed by gas from an overlaying high permeable gas cap. All personnel were safely evacuated.
In response to the incident, our well kill specialists were engaged to provide support and recommendations for the upcoming relief well drilling and kill operation.
What we did
Blowout analysis
Our specialists performed immediate simulations and evaluations in order to provide recommendations for the upcoming kill operation. The blowout simulations were based on the results from the latest reservoir modelling and surface observations.
Kill analysis
The dynamic kill simulations were based on the relief well being drilled from the jack-up rig West Triton located about 2 km away from West Atlas, by intersecting the blowing well in its horizontal section about 100 meters above the 9 ⅝” casing shoe.
We prepared a detailed kill plan prior to relief well intersection in order to assist the operator during the planning process. The kill plan included recommendations with respect to relief well intersection, milling and pumping schedule during dynamic kill and static kill operations.
In addition to the planning contribution, our specialists directed the final kill operation offshore.
