Contained top kill method and apparatus for entombing a defective blowout preventer (BOP) stack to stop an oil and/or gas spill

A method of stopping at least one of oil or gas from spewing from a defective blowout preventer (BOP) stack located on a floor of an ocean by entombing the defective BOP stack, the method comprising:

• (a) lowering a containment assembly below a surface of the ocean, the containment assembly having a hollow wall and a large diameter high pressure valve mounted on an upper opening of the containment assembly, the large diameter high pressure valve being maintained in an open position to reduce or eliminate buoyancy problems caused by the spewing oil or gas;
• (b) positioning the containment assembly on a portion of the ocean floor such that a hollow inner cavity of the containment assembly circumvents the defective BOP stack;
• (c) filling the hollow wall of the containment assembly with reinforcement material via a first set of valves;
• and
• (d) filling the hollow inner cavity of the containment assembly with the reinforcement material via a second set of valves.