Subsea slanted wellhead system and BOP system with dual injector head units

A method for performing well intervention, comprising:

• placing a template comprising at least one axially rotatable jack on the bottom of a body of water;
• lowering a conductor pipe to the template and supporting the conductor pipe at a selected inclination using the at least one jack;
• inserting the conductor pipe into the sub-bottom to a selected depth below the bottom of the body of water;
• drilling a wellbore for a surface casing from within the conductor pipe;
• setting the surface casing in the wellbore at the selected inclination;
• coupling a blowout preventer assembly to an upper end of the surface casing, a through bore of the blowout preventer assembly being oriented at the selected inclination;
• and
• coupling a spacer spool and an upper seal housing on top of the blowout preventer assembly, a through bore of the spacer spool and the upper seal housing having a through bore oriented at the selected inclination.

A method for performing well intervention, comprising:

• placing a template comprising at least one axially rotatable jack on the bottom of a body of water;
• lowering a conductor pipe to the template and supporting the conductor pipe at a selected inclination using the at least one jack;
• inserting the conductor pipe into the sub-bottom to a selected depth below the bottom of the body of water;
• drilling a wellbore for a surface casing from within the conductor pipe;
• setting the surface casing in the wellbore at the selected inclination;
• and
• coupling a blowout preventer assembly to an upper end of the surface casing, a through bore of the blowout preventer assembly being oriented at the selected inclination;
• wherein the inserting the conductor pipe comprises jetting the conductive pipe, and wherein the jetting is performed using a packer connected to a fluid line extending from the conductor pipe to the surface of the body of water.