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NSB completes first new Barrow gas well Major project to upgrade Barrow gas fields moves forward after completion of first horizontal well and pipeline modifications Alan Bailey Petroleum News
With the first of a series of new gas wells completed and modifications made to a gas transportation pipeline, work is moving ahead in a major North Slope Borough project to upgrade the gas fields that supply the City of Barrow with natural gas. The borough is upgrading the East Barrow field and the Walakpa field, two of the Barrow gas fields that also include the South Barrow field.
Matthew Dunn, North Slope Borough director for the capital improvement program, told Petroleum News Oct. 17 that the new well, drilled in the East Barrow field, was the first horizontal well that had ever been drilled in the Barrow region.
“We are very excited about that,” Dunn said. “We did finish the well last week and got things buttoned up.”
Second well starts The Kuukpik No. 5 rig that is doing the drilling has been moved to the location of a second new East Barrow well, with the drilling of that well expected to start on Oct. 18.
In addition to two new wells in the East Barrow field the project will involve the drilling of four wells in the Walakpa field. And to boost gas production by accessing as much gas reservoir volume as possible, all of the new wells will be horizontal. The first well resulted in 1,500 feet of well bore being exposed to productive reservoir rock, Dunn said.
The gas field upgrade, having already involved a major sealift of equipment to Barrow, is the largest project that the North Slope Borough has undertaken for a number of years; the project should ensure an adequate gas supply for the Barrow community for the next 25 to 30 years, Dunn said.
And the sealift to Barrow during the summer open water season was completed ahead of schedule.
“We completed barging operations in the third week of August,” Dunn said.
Most of the barges arriving in Barrow brought equipment from Oliktok Point in the central North Slope. However, one barge came from Seattle and another barge carried the Kuukpik rig from Nikiski on Alaska’s Kenai Peninsula.
Learning experience The first East Barrow well, characterized by Dunn as a learning experience, took a little longer to complete than the borough had planned. However, with that well now under its belt, the project team anticipates moving ahead more quickly with the next well, to maintain the project schedule.
“We learned a lot from the first well and we have a strong plan in place to apply those lessons learned to our next well,” Dunn said.
Access to the drilling sites in the Walakpa field will require the construction of an ice road. The borough has already started staking out the road route and expects to start pre-packing the road with ice fairly soon. However, actual road construction will likely start in December, once the ground is adequately frozen and there is adequate snow cover. Drilling at Walakpa is expected to start early in 2012.
The project team accelerated the schedule for making some necessary upgrades to the pipeline that transports gas from the East Barrow field. That work was completed in mid-September, Dunn said. The upgrades involved increasing the operating pressure of the line to enable, among other things, the carriage of sufficient gas from the East Barrow field to meet gas demand during any summer maintenance shutdown of the Walakpa field.
Well tie-ins Once both of the new East Barrow wells have been completed, the project team will install well houses and tie the wells into the upgraded transmission line. The borough hopes to complete that work by the end of the year, Dunn said.
In addition to tying in the two East Barrow wells, the project team plans to use the time period between the drilling at East Barrow and the drilling at Walakpa to plug and abandon some old, disused gas wells. There are eight wells to be plugged and abandoned, with some of those wells accessible on the existing gravel pad system and some requiring temporary ice pads for access.
The idea is to use equipment available as part of the field upgrade project to properly seal the old wells, thus addressing any safety concerns with these wells, Dunn said.
The borough’s project plan envisages completing the new Walakpa wells by the spring, so that the drilling equipment can be returned to Barrow for barging south in the summer. It will be possible to hook the Walakpa wells into the existing gas pipeline infrastructure using relatively short runs of infield piping.
Despite the large overall scope of the complete gas fields project, the borough feels confident that its very strong project team can meet the aggressive schedule for project completion, Dunn said. The borough anticipates completing the project on time, he said.
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