Ensco 8500 Ultra-Deepwater Semisub Gears Up for Anadarko, Eni

Ensco International Inc.

The ENSCO 8500, the first of seven new ultra-deepwater semisubmersible drilling rigs in the ENSCO 8500 Series®, has commenced operations in the Gulf of Mexico under a four-year contract with Anadarko and Eni.

Chairman, President and CEO Dan Rabun commented, "Over the past several years, we strategically have committed more than $3 billion to the expansion of our ultra-deepwater fleet to better serve the needs of our customers. Today, we achieved a milestone in the implementation phase of the ENSCO 8500 Series® deepwater initiative with the commencement of operations by ENSCO 8500 under a long-term drilling contract signed in September 2005." Mr. Rabun added, "Our ultra-deepwater semisubmersible drilling rigs complement our premium jackup fleet and will become a progressively larger segment of Ensco's total rig fleet around the world."

Combined with the ENSCO 7500 ultra-deepwater semisubmersible drilling rig currently contracted to Chevron in Australia, the fleet of seven ENSCO 8500 Series® rigs will make Ensco a leader in ultra-deepwater semisubmersible drilling rigs capable of operating in water depths of 7500’ or more.

The proprietary design of the ENSCO 8500 Series® was developed with extensive input from customers to address drilling requirements of virtually every deep water field around the world. Rated for work in 8,500' waters, Ensco’s new ultra-deepwater semisubmersible rigs may be modified to drill and complete wells in water depths up to 10,000'. The universal design of the ENSCO 8500 Series® rigs streamlines operational functionality, training, spare part requirements, repairs and maintenance to control costs and enhances the overall reliability of rig operations.

The next rig in the series, ENSCO 8501, is expected to begin operating in mid-October of this year under a three and one-half year contract in the Gulf of Mexico. The ENSCO 8502 and ENSCO 8503 are scheduled for delivery next year and both are under contract for two-year terms in the Gulf of Mexico.

The ENSCO 8504 is scheduled for delivery in 2011 and ENSCO 8505 and ENSCO 8506 are scheduled for delivery in 2012. These three ultra-deepwater semisubmersible drilling rigs are not yet contracted, and several operators have expressed interest in contracting them. Keppel FELS Limited built the ENSCO 8500 in Singapore and is constructing