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40 Years at Prudhoe Bay: BP, ARCO prepare to tame an elephant Initial development of the Prudhoe Bay field relies on seasoned workers, innovative logistics and historic equipment sealifts Petroleum News
As the dust settled after the Prudhoe Bay oil field was discovered in 1968, BP began development drilling, using Nabors 18-E and Brinkerhoff Rig 36.
Everett Potter, then a drilling consultant for BP, said rig technology has come a long way since those days.
“We used to tear the rigs down to the ground to move them by truck from one well location to another,” he recalled. “A rig move could take as long as seven days, especially during the winter months. Now, some of the rigs can be moved in half a day, and wheel-mounted rigs can simply be rolled to other locations.”
Modern cantilevered rigs can be moved from one well location on a pad to another location in just a matter of hours.
Brian Rose, a drilling superintendent for BP, joined the company in 1974 and became drilling foreman on the rigs.
“I got off the plane at Deadhorse and it was about minus 20 degrees (Fahrenheit) with a 30-mile-per-hour wind. A guy name Swede Swenson, a drilling foreman, picked me up at the airport in a yellow station wagon. I remember thinking to myself, “‘what have you gone and done now.’”
BP would operate the western side of the Prudhoe Bay field, or western operating area, or WOA, and ARCO would operate the eastern side, or EOA. The plan called for the six facilities to handle up to 1.8 million barrels per day of oil.
Unprecedented sealift shipments The first sealift to Prudhoe Bay occurred in the summer of 1969, when about 70,000 tons of stores and equipment were barged from Seattle. The 1970 barge sealift was the largest in the North Slope’s history — when 70 barges containing more than 175,000 tons of equipment journeyed north through difficult ice conditions.
From 1974 on, sealift shipments to Prudhoe Bay would contain oil production modules, buildings, modularized camps and other support facilities from the U.S. West Coast. The barge shipments were managed by Seattle-based Crowley Maritime Inc.
The first sealift also brought large modules for BP’s three gathering centers, which would separate gas and water from produced oil; ARCO would have three similar facilities, called flow stations, on its side of the field.
Massive capital investment in the ’70s By 1975, two of BP’s gathering centers were in place — each capable of handling about 300,000 barrels of oil per day.
During this period, a gravel “spine” road was built from east to west through the heart of the oil field, using gravel from approved material sites. Later, extensions and fingers off this road would access the many gravel “pads” from which development wells would be drilled. Pads were assigned letters on the western or BP-Sohio side of the oil field and numbers on the eastern, or ARCO side.
While initial facilities were being installed, expansions to those facilities were already being designed by BP in San Francisco.
During the mid-1970s, when major capital expansions reached a crescendo on both sides of the Prudhoe Bay field, area-wide population peaked at about 8,000.
BP’s first camp, Mukluk Camp, consisted of a few trailer units. The company’s permanent base camp was shipped in modular form from Seattle to Prudhoe Bay in mid-1973 on eight barges. The following year, the first phase of the Central Power Station arrived, which consisted of two turbine generators and a control rooms. The Prudhoe Unit agreed to locate it on the western side of the field — making it a BP-Sohio-run facility.
Later sealift shipments would bring the other three phases, which included five more Frame-5 turbine generators, which were fueled by natural gas produced in the Prudhoe Bay field. Today, the CPS has a maximum output capacity of 160 megawatts, making it the second-largest single power station in Alaska.
The CPS provides all power for Prudhoe Unit oil production operations. Diesel generators throughout the field provide a backup to provide life support, such as heating and emergency lights.
According to Jim Barrett, a supervisor at the station in the mid-1970s, the facility put out about two megawatts during its first year of operation.
In 1976, the three-story BP-Sohio center, sometimes called the BP Hilton, was expanded from 90,000 to 137,400 square feet, providing living and working room to accommodate about 264 people. BP also built two 500-worker camps for contractors developing the field.
Bill Lorenz, a BP North Slope construction veteran of about 25 years, said when Prudhoe facilities were first being installed, he couldn’t foresee what they would eventually look like or how big they would become.
“Most of the production modules and buildings were designed by BP and Ralph M. Parsons Inc. of Pasadena, and came from the U.S. West Coast as increments,” he said. “They were like jigsaw pieces of a bigger whole that we never saw until it was completed.”
“The initial gathering centers were almost ‘pass-through’ facilities compared to today’s multi-faceted complexes, and about one-third the size,” recalls Fritz Wiese, who spent many years on the North Slope as BP production manager.
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