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Kuparuk and its satellite fields move ahead under Phillips management Phillips is forging ahead with new development in the Kuparuk area, as well as maximizing production from the existing fields Alan Bailey PNA Contributing Writer
Following the upheaval and uncertainty associated with the takeover of ARCO a year ago, operations in Kuparuk have now settled down under Phillips Alaska Inc. management. “We’re probably having the best first quarter we’ve had in the last three years, if you look at the entire spectrum of production, safety management and environmental management,” Tom Wellman, Greater Kuparuk Area field manager, told PNA in April. Attention has particularly focussed on some exciting new satellite field developments, as well as on maximizing production from the Kuparuk field itself.
Wellman emphasized his delight with Kuparuk staff performance in recent months. He said that during the takeover it became very difficult for people to focus on their jobs. Now people have shifted their attentions from job uncertainties to the future of the oilfield. “It’s been a dramatic change in attitudes,” Wellman said.
Wellman also praised the contracting companies that support Kuparuk. The contractors up there have done a terrific job for us, he said.
Staff continuity has also assisted the transition to Phillips management — Phillips has kept much of the ARCO management team in place. “My operations team in the field didn’t really change,” Wellman said.
Work safety is paramount However, from the outset of its takeover of the ARCO operations Phillips has reinforced the importance of work safety, both with its own staff and with its contractors.
In particular, the company has recognized that staff morale and effective management underpin safety. “That’s the hardest aspect of our operations to manage, safety — you can’t get there unless people are feeling fairly secure and confident in their management,” Wellman said. Wellman feels really proud that he can look employees in the eye and talk about the way in which everyone has achieved their health, environmental and safety goals.
Phillips has actively worked with its contractors to heighten safety awareness. “We started probably third quarter last year, as we were selecting contractors, we let them know what our safety expectations were,” Wellman said. However, the contracting companies were themselves anxious to maintain a safe working environment: Phillips put its safety measures in place, while the contractors prepared their own safety plans. “(There was) a lot of pre-planning on our part, a lot of pre-planning on their part,” Wellman said.
In fact, Kuparuk has achieved a successful track record for safety over a number of years. In March of this year Central Processing Facility Two received the Governor’s Safety Award for six years of operation without a lost-time accident.
As well as their concern with safety, the Kuparuk staff have achieved an excellent record in environmental conservation. They recycle many materials, ranging from cardboard to drilling mud. Last spring the U.S. Environmental Protection Agency presented its Evergreen Award to Kuparuk, the first time that the agency has made such an award to an Alaska oil company. In October Kuparuk received the Interstate Gas and Oil Conservation Award for Environmental Excellence. In March, Kuparuk was recertified in the Green Star program.
A breakthrough at West Sak increases production Much of the recent Kuparuk development effort has focussed on its satellite fields, West Sak, Tabasco, Tarn and Meltwater.
“We’ve had what we think is a pretty significant breakthrough on West Sak, by putting in something called multilaterals,” Wellman said. “We’ve got a small but real innovative group of engineers basically looking at what’s been successful around the world and then dovetailing off that.”
A multilateral consists of a series of horizontal wells drilled out from a single well bore. By extending long horizontal wells from the same bore, drillers have been able to establish two production strings, one string in each of the main West Sak sand bodies. “If you extend those (strings) long enough you can get three wells’ worth of production out of one well,” Wellman said.
“(The wells group) has done a marvelous job of good well control — they know exactly where they are,” said Wellman. He explained that the drillers can keep the well within a 20 or 30 foot sand over a 3,000 or 4,000 foot section.
“We’ve (also) worked with our service companies on the connection of the multilaterals themselves,” Wellman said. “It’s been a really good joint effort.”
There are three West Sak wells which can each increase their production from 200 to 300 barrels per day to 1,000 barrels per day through the use of multilaterals. “And that’s really exciting for us,” Wellman said.
In its West Sak developments Phillips has been keeping in contact with BP, to exchange ideas about what works and what doesn’t work: West Sak is somewhat similar to BP’s Schrader Bluff field. “They try some things, we try some things, then we get together and talk about what’s the best practices,” Wellman said.
Continuing to bring in West Sak production through the existing infrastructure is also providing some interesting challenges, as a result of the relatively large amount of water in the West Sak production. Phillips is having to work out how to de-bottleneck some of the production plants — the plants were not designed to handle such high volumes of water.
Phillips is also evaluating the best techniques to use for enhanced oil recovery at West Sak. “There’s got to be a tremendous amount of good work (to do) — there’s a huge resource that we’re trying to capitalize on,” Wellman said. Water injection starts up in Tarn Wellman said that the emphasis at the Tarn satellite field has been shifting from drilling new wells to starting water injection. “We’ve got three drill pads out there at Tarn … they’re pretty much drilled up now,” Wellman said. “There’s probably limited drilling opportunities there, but the response has been incredible — it has been a really nice reservoir.”
Phillips is planning to bring a water line out to Tarn within the next month, in order to start water injection in the summer. “We’re trying to build the pressure back up in the reservoir a little bit — we pulled on it pretty hard initially, “ Wellman said. Phillips hope to increase production back to the low 20 thousands of barrels per day.
Paraffin has become a problem in Tarn. “We haven’t seen that particularly in Kuparuk before,” Wellman said.
The crude oil flowing up a well cools and deposits the paraffin as a heavy wax on the well tubing. “What you’re doing is necking down the cross-section … and therefore you have less flow,” Wellman said. He said that Phillips has looked at both mechanical and chemical fixes for the paraffin. “We have paraffin spray painting on our tubing and we have to pig our lines fairly frequently,” he said.
Phillips is now going to tackle the paraffin problems by pumping hot water through jet pumps to lift crude from the wells. In jet pumping, water goes through a throat nozzle, which creates a venturi effect. The venturi effect lowers the pressure inside the well bore, which then helps lift the crude.
The hot water passing through the jet pump will mix with the crude. “The heat within the well bore will minimize the amount of paraffin fallout that we have,” Wellman said. The Meltwater development moves ahead Meltwater, the newest Kuparuk satellite, is scheduled to start production in the fourth quarter of this year. “We should be moving our drilling rig out there early May to start what we hope will be about 26 wells,” Wellman said. “We think we’ve got about 50 million barrels of reserves there at Meltwater.”
Meltwater sits at the very southwest corner of the Kuparuk Unit, about 25 miles from Central Processing Facility Two.
The development of pipelines and an access road for Meltwater continues apace. “This spring by the time we get off the tundra we’ll have laid three pipelines out there … a 24 inch production line, a water line and an MI (miscible injectant) line,” Wellman said. “… we’ll have a gravel road all the way out there, we’ll have a new pad.”
The introduction of enhanced oil recovery early in the field life signals a major innovation: traditionally the use of miscible injectant follows natural pressure depletion and water flood. “We’ll have the MI lines to Meltwater almost immediately after startup,” Wellman said. By using miscible injectant early, Phillips expects to scavenge the maximum amount of oil from the reservoir.
“Put MI in the ground very rapidly and you’ll mobilize the most oil in the development,” Wellman said. “It’s a great deal for the state, it’s a great deal for us, because it’s going to maximize recovery.”
Phillips has worked with the regulatory agencies to address environmental concerns associated with the Meltwater development. “There are a lot of interesting issues about roadless development, caribou migration etc. — we’ve certainly made quite a few concessions to get that on line.” Meltwater opens up other prospects The placement of Meltwater at the southwest extremity of the Kuparuk Unit opens up some other exploration possibilities in that area. “There are a bunch of little exploratory prospects we could take a look at on the way out (to Meltwater),” Wellman said. “We’re pretty pumped up about that whole southwest corner.”
Phillips expects to drill two satellite exploration wells in the Kuparuk area this year and may get a third one in. “I think our geology and geophysics folks have done a great job of identifying where the little accumulations are, so we’re looking for the Kuparuk Sea Sands … there’s some Lisburne … there’s the smaller Tarn lookalikes … essentially between Meltwater and Tarn,” Wellman said. What’s really made a difference is our understanding of the differential geology for these types of reservoirs, he said. Kuparuk is performing above expectations The Kuparuk field itself is performing above expectations. Wellman attributes much of the excellent performance to the management of enhanced oil recovery and water flood.
It is particularly important to understand the best locations for enhanced oil recovery. “Our engineers have done a terrific job figuring out where to put MI,” Wellman said. You have to know where to put the miscible injectant in the ground to get the lowest gas oil ratios.”
Managing gas production also makes a crucial contribution to optimizing the Kuparuk field production. “You try to optimize as well as you can the limited gas handling capacity that you have … you can only handle a finite amount of gas,” Wellman said.
Phillips continues to make incremental improvements to the field operations, as well as evaluate new oil recovery techniques.
The company has started looking at the potential for using carbon dioxide for enhanced oil recovery, but the corrosive properties of carbon dioxide present some difficult problems, especially with the conventional steel completions in Kuparuk. “You think long and hard before you don’t at least isolate it in the field where you can deal with it,” Wellman said. The Kuparuk camp is very busy With a lot of development moving ahead on the North Slope, Kuparuk is particularly busy at the moment. The challenge has been the number of people in the Kuparuk camp, said Wellman. Normally, about seven or eight hundred people stay in the camp. “This year we had a peak late January or February of 1,210 people in camp,” he said. “It’s the biggest hotel in Alaska.”
And so, with Meltwater coming on line, with new exploration activities and with new technical developments, there is a lot going on in North America’s second largest oil field. Indeed, Kuparuk sits high in Phillip’s portfolio. “These assets are probably far and away the best thing they have,” Wellman said. The future certainly looks exciting.
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