ENSCO 8501 Spins Bit in Ultra-Deepwater GOM

The ENSCO 8501, the second of seven new ultra-deepwater semisubmersibles in the ENSCO 8500 Series®, commenced operations in the Gulf of Mexico on October 8 under a three-and-a-half year contract with Nexen and Noble Energy.

Chairman, President and CEO Dan Rabun commented, "We have achieved another important milestone with ENSCO 8501 commencing operations. Ensco already has invested more than half of the $3 billion committed to the ENSCO 8500 Series® newbuild program, and we are well on our way toward having the world's largest fleet of ultra-deepwater semisubmersibles capable of drilling in water depths of 7,500' or deeper," Mr. Rabun added, "We now have three ultra-deepwater semisubmersibles in our active fleet to complement our premium jackups around the globe."

As planned with the customer, commencement of operations began by spudding the initial well followed by a short period of final acceptance testing (estimated 7-10 days at zero rate in October) before recommencing operations. No similar planned downtime is anticipated going forward.

The proprietary design of the ENSCO 8500 Series® was developed with extensive input from customers to address the drilling requirements for virtually every deepwater field around the world. The design includes a 35,000' nominal rated drilling depth, 2 million pounds of hoisting capacity, 8,000 tons of variable deck load and an open layout well suited for subsea completion activities. Improved visibility from the open deck configuration also enhances safety.

The uniform design of the ENSCO 8500 Series® streamlines operational functionality, repairs, training, spare part requirements and maintenance, while also providing flexibility for customer specific enhancements. In particular, the 8500 Series may be modified to drill and complete wells in water depths up to 10,000'.

Senior Vice President Carey Lowe stated, "Recent major discoveries in the ultra-deepwater golden triangle of the Gulf of Mexico, Brazil and West Africa highlight the growing need for ultra-deepwater drilling. ENSCO 8500 Series® semisubmersibles are ideally suited to drill in these regions, as well as Australia, Southeast Asia and many other ultra-deepwater markets."

ENSCO 8502 and ENSCO 8503 are scheduled for delivery in the first and fourth quarters of 2010, respectively, each with two-year contracts in the Gulf of Mexico. ENSCO 8504 is scheduled for delivery in 2011. ENSCO 8505 and ENSCO 8506 are scheduled for delivery in 2012. Keppel FELS Limited is the builder of the ENSCO 8500 Series® seven-rig fleet.