THE EXPEDITION WAS composed of twenty-two members. These included: Eric Simonson (leader); George Dunn (assistant leader) and others. Fourteen of the members were mountain guides who had nineteen previous attempts on Everest between them.

Two different groups reached Xegar, Tibet on 10 March. Ten members travelled via Lhasa, Tibet and accompanied 5500 kg of food and equipment that had been shipped to China in November, 1990.

The rest of the team came via Kathmandu, Nepal where they met the 13 Nepalese members (two cooks and 11 Sherpas). Propane fuel, oxygen and additional food were also brought in from Nepal.

Base camp was established 13 March a.t 5150 m___ the end of

the road. It took 50 yak loads to establish C3 (advanced base camp), a week later at 6520 m. Severe weather and heavy snow made it impossible to reach the North Col (C4) at 7000 m until 30 March. The route to the Col was fixed with ropes and eventually 130 yak loads reached ABC.

C4 consisted of eight tents, walled in and held down by nets. Extremely high winds, often exceeding 70 mph for days on end, prevented C5 at 7800 m from being established until 21 April. Without the ropes, which were fixed on this part of the route, there would have been many days where we could not have climbed due to the extreme wind across the North Ridge.

C5 was again an extremely windy site. Only our four China-Everest tents were able to withstand the beating. C6 at 8230 m was established on 7 May after a long hard push that forced Wilson, Whetu, Okita, Edwards and Van Hoy to all spend the night in a. tiny two-person tent.

Every member of the team who was healthy got a summit bid. This was the plan from the beginning. On 15 May the top was reached by «5imonson, Dunn, Polite, Sloezen, Lhakpa Dorge Sherpa and Ang Dawa Sherpa. An attempt the next day by Hahn, Rheinberger, Perry, Huntington, Ang Jangbo Sherpa and Pasang Kami Sherpa was turned back by high winds. Perry stayed at C6 while the rest descended and made the top solo on 7 May. An attempt on 21 May by Wilson, Edwards, Van Hoy, Frantz, Whetu and Okita was also partially stopped by the wind. Only Whetu and Okita were able to push on and reach the summit. Okita was forced to bivouac on the descent at 8530 m when he couldn't find the fixed ropes in the 'Yellow Band' above C6 in the dark. Fortunately, he suffered no ill effect from his adventure. Wilson remained at C6 for three more days and was joined by Mann for another attempt on 24 May. On the previous day, Peck had been stopped below C6. Ultimately, Mann was forced to turn back, but Wilson reached the summit.

All summiters used oxygen, though Wilson and Perry tried initally without. Van Hoy and Hahn also tried without, but were unable to stay warm enough. The team left base camp on 28 May and all members returned home via Kathmandu.

Rongbuk Research
Dr Daniel Mann of Fairbanks, Alaska, joined the expedition to study the extent and age of glacial moraines in the Rongbuk valley at elevations between 4500 m - 6400 m. His work consisted of examining different glacial moraines looking at the condition of weathering pits, the degree of soil development, and the diameters of lichens on surface boulders. The lichens help in estimating the age of the geological formations and as such were absent from the youngest moraine but were up to 30 cm in diameter on the older moraines. Lichens of this size in polar regions are known to be more than 5,000 years old.

Dr Mann's preliminary results show that the Tibetan ice caps assumed by previous geologists to have covered Tibet during the last Ice Age in fact never existed. Instead, the Rongbuk valley has been glaciated intermittently over the last 100,000 years by ice originating locally on the north side of Everest. The field research also showed that moraines of four different ages are preserved in the Rongbuk valley.

One of the difficulties encountered by Dr Mann was locating organic materials suitable for radio carbon dating. Nonetheless, he brought back two peat samples which will be analyzed in the laboratory to determine more precise dates from some of the younger moraines. After this work is complete, Dr Minn's results will be utilized through a process of correlation to provide similar information for some of the better vegetated valleys to the east and south of Everest.

Ohmeda's Results
Oxygen saturation research sponsored by the Ohmeda Corporation was conducted by expedition member Jonas Pologe during the 74 days on Everest. The purpose of this research was to add to our knowledge of how people adjust to and compensate for the effects of high altitude.

The climbers were connected to an Ohmeda 3740 Pulse Oximeter, a device which reads the oxygen saturation of the arterial blood continuously and non-invasively. Arterial oxygen saturation (SaO2) is the percent of hemoglobin that is bound to oxygen divided by the total amount of hemoglobin available. At sea level the normal SaO2 is about 95% whether at rest or during exercise. The resting SaO2 of the climbers, on the first two days of the climb, averaged about 83% while the average SaO2 at the end of exercise was roughly 69%. Over the course of the climb the resting SaO2 levels increased only slightly while the average end of exercise saturations increased significantly to just over 80%.

This rather dramatic improvement in oxygen saturation during exercise in the acclimatised climber had not been noted before and certainly helps to explain the improvement in performance one achieves with a long stay at high altitudes. Further analysis is expected to explain the physiology behind the improved SaO2 readings observed.

The Video
Participating in the expedition was * Markus Hutnak of Pullman, Washington, ¦ who was responsible for the expedition's video work. Markus operated two Ricoh video cameras, one of which went all the way to the summit, courtesy of Brent Okita. Based on this and additional footage from Mark Whetu and Charlie Peck, Markus is currently preparing an in-depth video account of the climb. A CBS affiliate, KIRO-TV in Seattle, Washington, is helping with the project.

Markus' 30 hours of Hi-band 8 mm videotape includes dramatic footage of a climber being blown down the glacier during a windstorm, climbers on the summit, a yak trapped in a crevasse, a tent burning, and an actual recording of the radio broadcast from the highest point on earth.

A Clean Climb
The American North Face Everest Expedition made a commitment from the beginning to minimize its impact on the environment of Mt Everest. At considerable expense we removed dozens of yak loads of trash from Advanced Base Camp at 21,400 feet. This included picking up after previous expeditions. At Base Camp we worked with the Swedish and British groups that were there and collected dose to 8,000 pounds of garbage. This was trucked out to the village of Xegar for proper disposal. We challenge and encourage future expeditions to do the same and preserve Everest's unique and fragile environment.

Summary: The dimb of Everest (8848 m) by the North Face by an American team in summer 1991.