As the building of the new U.S. Amundsen-Scott South Pole Station continues towards its completion date of 2007, it rests on "the bones" of three earlier structures.
The U.S. established a base at the Pole after their first landing there during the 1956-57 season. The base was built as part of the International Geophysical Year Programme. Initially, the first buildings were Jamesways, with all parts airdropped onto the Polar Plateau. This first base had limited primary electrical power sources and relied on High Frequency (HF) radio to communicate with the outside world. The design of a second and more permanent base with a 15-20 year life span began in 1967, and included a large geodesic dome that sheltered pre-fabricated modular buildings from the snow and wind. Construction beganin 1971 and was undertaken entirely by U.S. Navy Seabees.
In 1973 the construction of a series of steel archways, which extended radially from the Geodesic Dome, was begun. Like the Dome, the steel arches sheltered pre-fabricated modular buildings. HF Radio continued to be the dominant media for external communication. The base was completed and occupied by 9 January 1975. It housed 33 men during the summer and 18 during the winter. By the late 1980s the steel archways had become well covered by snow but showed no signs of structural strain. However, the geodesic dome, primary electrical power systems, and the utility systems were showing signs of age and structural/mechanical stress.
The fourth and current South Pole station had an entirely new design. It reused the buried archways as service structures, and linked them through a utilidor tower to a new habitate structure to be constructed on adjustable columns above the snow surface. The building had the ability to be raised as snow accumulated, and construction would be phased.
The new base would have a life of 25 years, housing 110 people in summer (subsequently increased to 150)
and 50 people in winter. Power sources and telecommunications would be upgraded.
Construction began in 1997. A test structure on steel columns was built first in the U.S. to verify that the steel members were properly sized and that bolt holes were properly aligned.
This was then erected at the South Pole. A much larger garage arch was completed in 1999, and in 1999-2000 a new power plant with the capacity of one megawatt (cf 450 Kw in 1975) was also constructed within the steel archways. In December 2000 communications were greatly improved by the commissioning of a broadband Earth Satellite Station and associated 9-metre tracking antenna. Fuel storage was greatly increased, with careful regard to environmental standards for secondary containment. Previously there were nine composition-material bladders storing 225,000 gallons of fuel which were susceptible to leaks.
The new bulk fuel storage facility will have 45 steel tanks capable of storing 450,000 gallons of fuel. Each tank will be mounted in a "boat" to contain accidental spillage, and distribution lines will be configured with sensors to alert for breaks and seepages.
In March 2003 the A-i section of the new base was officially occupied, with a fully functioning kitchen and dining room (See Antarctic Vol. 20, no. 3&4, p. 59). At present there are 58 people wintering over. Nine of these are scientists, 24 are construction crew, and 25 are support personnel. However, only 40 people are living in the new base, and the remaining eighteen are housed in the Dome complex of the old base. Building the remainder of the base will continue over the 2003-04 season. During the summer 93 workers will concentrate on exterior construction, working 24 hours for six days in three shifts. During the 2004 winter, 41 workers will work a shift of nine hours on six days to complete the internal work. When completed, the new base will have cost a total of US$ 161 million, and will have required 929 LC-130 flights, each carrying 26,000 lbs of construction cargo. By the end of last season (March 2003), 623 of these flights had already taken place.
The U.S. National Science Foundation (NSF) will continue to evaluate its proposed overland traverse route to the South Pole this coming season. Last year, during the first season of a planned three season Proof of Concept, the traversing team negotiated a route through a five km wide major shear zone near Minna Bluff, blasting open crevasse bridges and back filling them with snow (see Antarctic Vol. 20, no 3 & 4, p. 38).
This season the team will check for changes to the infilled crevasses and then evaluate a route across the Ross Ice Shelf to the bottom of the Leverett Glacier. An engineering assessment of tractor pulling power, as well as an evaluation of the structural integrity and flexibility of ski undercarriages is also part of the seasonal plan. Optimization of different tractor-sledge configurations will also be analysed. Each train will be configured with accommodation sledges, food storage vans and fuel tanks.
Art Brown, NSF representative in Christchurch, said that six tractor trains to the South Pole had the potential to deliver 244,400 pounds of mixed cargo if the route could be proven. Each group of up to six tractor trains will constitute a "Swing", one swing traveling to the Pole and back. Three swings, each successfully completing three round trips from McMurdo Station to South Pole and return during one austral summer season, would be equivalent to 84 Hercules LC-130 flights to the Pole, and would allow larger objects to be carried than could be fitted into an LC-130.
The final part of the "Proof of Concept Traverse" will take place next season when a tractor train will climb the Leverett Glacier, cross the Polar Plateau to the South Pole, and return to McMurdo Station.
In the U.S. the NSF has filed a public "Notice of Intent" to proceed with the submission of a Comprehensive Environmental Evaluation (CEE) for the Development and Implementation of Overland Traverse Capabilities in Antarctica.