Chevron is permitting four new well locations at its White Hills prospect south of the Kuparuk River unit in the central North Slope, according to filings with the state.
The proposed wells — Bluebuck 6-7-9, Moropus 16-6-8, Panthera 21-6-9 and Stegodon 24-6-8 — are all focused toward the northern end of the prospect.
Through its wholly owned subsidiary Union Oil Company of California, or Unocal, Chevron permitted 15 proposed well locations for the 2007-08 winter drilling season.
This past winter, the company drilled three wells spaced across the prospect, a bundle of state leases stretching nearly 50 miles from north to south. One of those wells, Panthera 28-6-9, seems to be the launching point for the well locations proposed for this winter.
Of the new well locations, the Panthera 21-6-9 and Bluebuck 6-7-9 sit one mile and 12 miles respectively to the north of Panthera 28-6-9, while Moropus 16-6-8 and Stegodon 24-6-8 sit a few miles to the north and northeast of the previously proposed, but as yet undrilled, Stegodon 34-6-8 well location, just to the southeast of Panthera 28-6-9.
In addition to Panthera 28-6-9, Chevron drilled Smilodon 9-4-9 and Mastodon 6-3-9 this past winter using Nabors rig 106E, which the company plans to use again this winter.
Chevron named all the proposed wells in the White Hills prospect after prehistoric animals. The numbers following the well names refer to section, township and range.
Through Unocal, Chevron is the operator and majority interest owner of the White Hills prospect. Over the summer, Chevron brought on Total E&P USA Inc., a subsidiary of the French major Total S.A., as a 30-percent minority partner on the project.
The state is taking comments on the proposed exploration wells through Dec. 15.
Some 75 miles of roadsThe White Hills prospect sits some 20 miles west of the Dalton Highway.
Road construction required for the venture includes a 37-mile trail from the state-owned Franklin Bluffs staging area on the Dalton Highway to the first drill site, and an additional 38 miles of infield snow trails connecting to the other proposed drill sites.
Using snow trails or ice bridges, Chevron plans to cross the Toolik and Kuparuk rivers, as well as several unnamed streams, to access the proposed drill site for Panthera 21-6-9.
If enough snow falls early in the season, Chevron plans to pre-pack trails before the end of the year “to expedite frost penetration.” Otherwise the company will build “an improved ice trail” similar to those built in support of drilling operations this past winter.
The state and federal agencies that oversee resource development on the North Slope restrict travel across the fragile tundra until snow depths and ground temperatures reach certain thresholds. As of Nov. 14, those conditions had not been met in the areas monitored by the state, including those required for exploring the White Hills prospect.
‘Relatively shallow’ wellsChevron drilled Panthera 28-6-9 to a depth of 2,020 feet this past winter, much shallower than the roughly 5,000-foot wells drilled at Smilodon 9-4-9 and Mastodon 6-3-9.
Because the newly proposed wells are also “relatively shallow,” Chevron expects each to take between 20 and 27 days to drill and evaluate, allowing the company to drill between two and five wells depending on weather conditions. Chevron hopes to drill its first well in December or January, and any remaining wells between February and April.
Chevron has not ruled out expanding the White Hills exploration program to a third year.
Calling the program a “tight” venture, Chevron has declined to identify the target of the White Hills effort, or release any results from the first year of the drilling program.
Previous wells drilled across the current White Hills acreage have had oil and gas shows.
The newly proposed wells sit near the Texaco Wolfbutton 32-7-8 and Wolfbutton 25-6-9 wells drilled in the winter of 1988-89; BP Exploration drilled the Narvaq No. 1 in the winter of 1990-91. None of those three wells yielded significant finds.