With the ice-free drilling season nearing an end, Shell Oil started its first exploration well in the Chukchi Sea off the northwest coast of Alaska on Sunday.
At 8:30 a.m. Eastern, the Noble Discoverer began drilling. On Friday, the drilling rig was moored to eight anchors, spread in a circular pattern 6,500 feet across on the sea floor to center the rig over the well. Each anchor weighs several tons.
The company said crews on board would drill a pilot hole roughly 1,400 feet deep, stopping well short of the oil-bearing reservoirs while the company finishes work on a spill- control vessel it needs in place before getting final permits.
Last week, the Interior Department said Shell could drill the pilot hole and the 20-by-40-foot hole called the mud line cellar, which will house the blowout preventer and allow it to sit below the sea floor. The company also will install casing and cement in the top portion of the well.