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Drilling moves west Phillips Puviaq well site in NPR-A will be farthest west North Slope exploration drilling in decades; prospect is 65 miles northwest of Hunter Kristen Nelson PNA Editor-in-Chief
Phillips Alaska Inc. 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 Puviaq 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 Exploration (Alaska) Inc. drilled last year, and, other than development drilling at the Barrow gas field, will be the farthest west North Slope drilling in several decades. Recent leases The 35-16N-10W,UM, coordinates place the proposed Puviaq pad on a Phillips-Anadarko Petroleum Corp. (78 percent, 22 percent) lease close to the western boundary of currently leased NPR-A acreage south of Smith Bay. The Puviaq pad would be some 65 miles northwest of Phillips’ Hunter exploration well and some 72 miles northwest of the Mitre and Lookout prospects where Phillips is also working this winter season.
ARCO Alaska Inc. (now Phillips Alaska) and Anadarko paid as much as $210.01 an acre for seven tracts west of Teshekpuk Lake in the 1999 NPR-A lease sale. This group of tracts is in the area of the NPR-A lease sale characterized by the Bureau of Land Management as having a lower probability of hydrocarbons.
The Puviaq pad would be on a tract for which the companies paid $203 an acre. The $210.01 an acre tract is immediately to the east.
BP Exploration (Alaska) Inc. and Phillips Petroleum Co., bidding jointly, paid an average of less than $8 an acre for an adjacent block of five tracts to the south; Chevron is now a partner in that acreage. By rolligon Phillips would mobilize a crew of as many as 20 people and selected ice pad construction equipment by rolligon or other all-terrain vehicles to the site for pad construction, the Corps of Engineers said. The drilling rig would be moved to the site by rolligon after construction of the pad but prior to 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 main rolligon trail for this activity will begin near Phillips’ Spark No. 5 and continue westward into NPR-A.
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 eight foot by 24-foot by approximately four inch to six inch thick, 25 psi expanded polystyrene foam insulation. The panels weigh approximately 700 pounds each. Sandwich construction The polystyrene panels will be sandwiched between eight-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 would be approximately three feet high, roughly trapezoidal in cross-section with an eight-foot wide base and a four-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. BP used insulated pad Foam-core panels have been used to insulate ice pads on the eastern side of the slope.
BP Exploration (Alaska) used foam-core panels to insulate drilling pads some 50 miles east of Prudhoe Bay in the early 1990s.
The 400 foot by 300 foot by six inch Yukon Gold ice pad was built in the spring of 1993, covered in plastic sheeting and topped with 600 foam-core panels. Each five-inch thick panel measured eight feet by 24 feet and weighted 700 pounds. The panels were anchored and covered with a surface material to reflect sunlight.
The Yukon Gold insulated ice pad enabled the company to begin work earlier in the winter season, without having to wait for temperatures cold enough to build an ice pad.
BP used the same insulated at the Sourdough No. 2 ice pad, constructed in January 1994. The panels were placed under all facilities at Sourdough No. 2 — modules, tanks and camps — so facilities could remain on location through the summer, BP said. The panels at Sourdough were picked up in April, but BP said they were in excellent shape, “and it was expected that there would have been no problems leaving the rig on the panels through the summer.”
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