Petroleum News March 2002 reprint

Following is abbreviated text from an article that appeared in the March 24, 2002, issue of Petroleum News by Kristen Nelson.

Phillips Alaska is planning winter exploration drilling next year on some of the farthest west leases in the National Petroleum Reserve-Alaska. The company has applied to build a 1.5 acre insulated ice pad in order to keep a drilling rig in the area over the summer.

The Puviag insulated pad, according to the U.S. Army Corps of Engineers, would be west of Teshekpuk Lake approximately 67 miles southeast of Barrow in section 35 township 16N range 10W, Umiat Meridian. The Corps said no drilling operations are planned for this site. The rig would be moved to a “nearby winter exploratory drilling site” after tundra travel is approved for the 2002-2003 winter season.

This prospect is some 45 miles west-northwest of the Trailblazer prospect BP drilled last year, and, other than development drilling at the Barrow gas field, will be the farthest west North Slope drilling in several decades. …

Phillips will mobilize a crew … and construction equipment by rolligon or other all-terrain vehicles to the site for pad construction, the corps said. The drilling rig will be moved to the site by rolligon after the pad is built but before the close of tundra travel this spring and then moved to a nearby winter exploratory drilling site after winter tundra travel reopens in late 2002 or early 2003.

The corps said the insulated ice pad would be approximately 245 feet by 265 feet by six inches thick. Construction is expected to begin in March. The ice pad will be covered with standard … 4 to 6-inch thick, 25 psi expanded polystyrene foam insulation. The panels weigh about 700 pounds each.

The polystyrene panels will be sandwiched between 8-foot by 24-foot sheets of 7/16-inch thick oriented strand board. Reinforced polyethylene film will be laid under the panels to prevent them from bonding to the ice pad to ensure easy pick-up.

Exposed panel surfaces will be covered with a white, opaque surface fabric that is designed to minimize thermal gain, minimize rainwater infiltration to the ice surface and minimize thermal erosion of the ice pad.

Standard rig mats will be placed on the insulated panels with the drilling rig sitting on the mats. Ice berms may be constructed to divert spring runoff from the pad. The berms will be about 3 feet high, roughly trapezoidal in cross-section with an 8-foot wide base and a 4-foot wide top.

Rope anchors will be used to resist wind uplift forces on the panels not protected by the rig and the site will be monitored every two to three weeks over the summer to collect data from 10 or more thermistor sensors monitoring ice-surface temperatures and to provide side maintenance. …