The system includes a containment housing with an open bottom which is configured to fit over an undersea oil well pipe which is spilling oil, the housing being lockable to a platform or ring surrounding the oil well pipe or positionable on the sea floor. A pipe is positioned internal of the housing into which the oil well pipe can be fitted, the vertical pipe being directed to or connectable to an evacuation pipe which extends to the surface of the sea, through which the oil from the well moves by means of an evacuation pump. The oil is pumped at a rate approximately at least as great as the rate of the oil spill. An infusion line and associated pump is connected to the chamber for pumping mud and/or cement and/or concrete into the chamber to stop and seal the spill and to ensure the housing remains positioned over the oil spill well pipe.