The initial funding will be invested in detailed engineering and the procurement of long lead time equipment related to the hull, topsides and subsea equipment, BHP said.
The project includes the development of a second spar facility with all subsea production and injection wells.
The new facility is estimated to have a design capacity of about 130,000 barrels a day that would be exported through the Mardi Gras pipelines.
A final investment decision on the project is expected next year, with first production scheduled for 2018, the company said.
BHP holds a 23.9% stake, BP as operator has a 60.5% share and Chevron Corp 15.6%.
