Abstract: A containment system having a containment dome and a seal plate which is attached to an oil wellhead casing or riser to prevent oil spills and contamination when an oil leak occurs. The containment dome is sealed to the seal plate by a compression mechanism so that oil will not leak from the containment dome. The containment dome can provide a wellhead patch to a wellhead system wherein the wellhead patch can interface with a capping stack. Chemicals can be injected into the containment dome to prevent hydrates from forming. All aspects of controlling and operating an oil wellhead can be performed through the containment dome and seal plate, and all aspects of installation, regulation, and control of the containment dome can be performed by remote operating vehicles under water.

Abstract: A riser disconnect/reconnect system including a disconnection package (RDP) and a modified lower marine riser package (LMRP) are provided for quick disconnection of the marine drilling riser (MDR) from the LMRP. The RDP includes a flex joint and a release connector (RC) with a mandrel that engages a modified LMRP. In an emergency event, the RDP is disconnected from the LMRP allowing access to the BOP stack for emergency intervention. In routine drilling operations, the RDP is disconnected from the LMRP facilitating the recovery of the LMRP or BOP stack to the surface for repair or maintenance without recovering the MDR. The RC joins the flex joint to the uppermost annular blowout preventer in the LMRP. The RC is configured for use in a standard or inverted position. Also provided is a mechanical locking connector, a resident ROV and sonar technology and methods of using same with the RDP.