Mar. 2013 - Shenandoah-2, Anadarko's US Gulf of Mexico deepwater well, encountered over 1,000 net feet of oil pay in multiple high quality Lower Tertiary reservoirs. The well was drilled by the Ensco 8505 (UDW semisub) to a total depth of 31,405 feet in 5,838 feet of water. Well data indicates excellent quality reservoir and fluid properties. The well was drilled to test the down-dip extent of the Shenandoah-1 discovery and was found to be full to base with no oil-water contact observed.

Jul. 2012 - Anadarko is currently drilling the Shenandoah appraisal well in Walker Ridge 51 in approximately 5,800 feet (1,768 meters) of water. The operator is using the ENSCO 8505 (UDW semisub) to drill the well to a proposed depth of 32,000 feet (9,754 meters).

Jun. 2012 - The BOEM recently approved Anadarko's permit to drill at its Shenandoah prospect in Walker Ridge Block 51. The permit lists the ENSCO 8505 (UDW semisub) as the rig that will perform drilling operations. The Shenandoah well has a proposed depth of 32,000 feet (9,754 meters) and is located in approximately 5,800 feet (1,768 meters) of water.

Feb. 2009 - Anadarko Petroleum Corporation announced its second deepwater Gulf of Mexico discovery this week. The Shenandoah discovery well, located in Walker Ridge Block 52, encountered net oil pay approaching 300 feet in the Wilcox formation.

Sep. 2008 - Noble Corporation has reported that the Noble Paul Romano semisub rig experienced mooring failures and drifted from its original respective location on Walker Ridge 52, Anadarko's Shenandoah prospect, but has been boarded and power has been restored. Tugs are on station to assist with the start-up of each of the rig and other than the above mentioned mooring equipment, there is no other apparent significant damage.

May. 2008 - Anadarko is preparing to spud its lower tertiary prospect, Shenandoah, using the Noble Paul Romano semisub. Drilling activity is expected to take approximately 200 days.