The platform was closed temporarily in the first quarter of 2005 due to a planned replacement of flexjoints on both its oil and natural gas export lines. The fabrication of the modules was completed by McDermott. It has an open-truss framing design, which is 245ft x 245ft x 45ft and weighs approximately 7,200t. The deck is composed of five modules, namely the wellbay, living quarters, processing, power and drilling. The fabrication of the hull was completed by Belleli of Taranto, Italy. The hull comprises four circular steel columns, which are 66.5ft in diameter and 162ft-high, and four pontoons, 27ft-wide and 24ft-high, which connect the bottoms of the four columns. The TLP was designed to withstand hurricane force waves of 71ft and winds of 140mph, simultaneously. Mars’ TLP is 3,250ft-high from the seafloor to the crown block of the drilling rig, and its steel weight is approximately 36,500t. The contract rig H&P 201 was installed on the TLP to drill the remaining wells. Ten tension leg platform (TLP) development wells were predrilled with George Richardson, a Sonat semisubmersible rig. The remaining 45% was spent on drilling and completing the wells. Out of the total project cost 55% was dedicated to the fabrication and installation of the hull, deck facilities and pipelines. The cost of the development for the initial project phase was approximately $1bn.

The initial development was designed to recover about 500 million barrels of oil equivalent (Mboe).

Louisiana offshore oil port map