Mount Logan High Altitude Project – 1970. The Arctic Institute of North America again operated its research facility on the summit plateau of Mount Logan at 17,600 feet. Research was again carried out in high altitude human physiology, climatology, and glaciology, with an additional program – an attempt to measure DDT and other contaminants in snow cores obtained high on the mountain. In early June the climbing parties started up the west-buttress route. One group, consisting of Melvin Marcus, Elizabeth Witherill, A.J. LaFleur, and William Hereford, excavated snow pits, for Stratigraphie studies, every thousand feet. The second group, Thomas Stengle, Lawrence McGee, Carol Harden, Gail Davidson, Richard Wilcox, and Joseph LaBelle, started up later; all reached the summit plateau by June 15, after weathering several storms on the ascent. The party dug out the buried cache of equipment and supplies and erected three Versadome buildings plus a plywood outhouse-generator building. The old buried hut, built in 1967, was tunneled into and found to be buried under approximately thirty feet of snow and collapsing badly. It was again used for storage during the summer, but was finally abandoned. Phil Upton, the Institute pilot, began ferrying supplies to the high camp on June 23, after several days of storms. Marcus and others set up meteorological and micro-met equipment, and began keeping regular records. DDT sampling was begun by Stengle, and snow studies were initiated by LaBelle. By July 4 the camp was ready and the physiologists flew to the mountain. Throughout the season Drs. Gary Gray, Drummond Rennie, Regina Frayser, David Sinclair, and Charles Houston, and technician Ivan Sherlock, carried out physiological studies on the support team and a group of ten volunteers from the Canadian Forces Airborne Regiment. On July 6 a Canadian Forces Buffalo aircraft made a dozen parachute drops of supplies and equipment. Two chute loads that hit the target perfectly were lost when winds rose and wafted the loads aloft before they could be secured, carrying them off the north face of the mountain. By July 20 the physiology program was completed and the doctors and volunteers flown out. On the 24th the support team left for the main summit, 19,850 feet. Stengle, Wilcox, Harden, and LaFleur made the summit on the 26th, and Hereford, Witherill, Davidson, and LaBelle reached the top the following day. The first four returned to the research camp, while the last four made the ascent of the 19,700-foot east peak on the 28th. On the following day the worst storm in the history of the project set in, stranding these four at their high camp on a ridge at 18,600 feet for several days. Continual blizzard, with dense fog and winds of well over 100 miles per hour pinned the group down, and they were not able to return to the research camp on the summit plateau until late on August 3, when the storm finally broke. The next few days were spent dismantling and caching the high camp, which had weathered winds up to 80 miles per hour on the relatively protected plateau; only the outhouse-generator building had blown apart. The group then returned to the Kluane Lake Base Camp, completing another research season on the mountain.

Physiological summary. As in previous years principal attention was focused on the changes which take place in the retina of individuals at high altitude. In contrast to earlier years, during the summer of 1970 we saw only a few retinal hemorrhages among the acclimatized and rapidly exposed people at Logan High. However, all of the retinal photographs show the increase in diameter of blood vessels, the increased tortuosity of blood vessels, and the impression of excess blood flow which we have come to associate with this altitude. One of the physicians, an experienced mountaineer who had spent a great deal of time at high altitude developed a very severe headache and was thought to be approaching cerebral edema before he was evacuated. He recovered in several days and was not at any time critically ill.

An effort was made to measure the distribution of water in the body, between cells, tissue, and in the blood. These studies were done at Base Camp first, and repeated on several occasions at high altitude. The data are not in agreement with previous observations, and are being subjected to statistical analysis at present. We were able to confirm the absolute imperative of adequate water intake in protecting people against the symptoms of mountain sickness. If there is any single thing which is important for the high altitude climber it is being certain that he takes very large amounts of water every day that he is at altitude.

We added an interesting side study in 1970. The current interest in the environment has demonstrated that pesticides such as DDT are usually found wherever they are searched for. In fact DDT has been described as the most widely distributed man-made chemical in the world and has been found in Antarctic penguins, all fish, most mammals and birds, and in water almost everywhere on earth. It seemed worthwhile to determine whether or not DDT had contaminated the snow which fell on the high Logan plateau many years ago. Consequently snow-core samples were taken by standard glacial techniques and snow obtained which is believed to have fallen at least twenty years ago. Precautions were taken to avoid contamination by the drill, clothing, or in handling the cores. These were placed in specially cleaned bottles, thawed at Base Camp, and transported to the Federal Water Quality Administration Laboratories in Cincinnati where they were studied for DDT content and other contaminates. So sensitive is the technique however that one of the elements used to coat the auger was detected in the snow samples in sufficient quantity to mask any possible content of DDT. This occured in spite of the most rigorous cleaning of the auger with triply distilled nitric acid! At this writing therefore we cannot say with any certainty whether or not DDT actually occurs in the snow on Mount Logan, and we plan to repeat the studies in 1971. This work was made possible by a small contract with the Department of the Interior.

JOSEPH C. LABELLE and CHARLES S. HOUSTON, M.D.