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Fall on Snow – British Columbia, Mt. Lefroy

FALL ON SNOW—British Columbia, Mt. Lefroy. Bill Tarchuk, Mike Krinsley, and Su-Chong Lim started to climb the east slope of Mt. Lefroy from Abbot Pass on August 6. Low down, the snow was soft with a mushy crust, but steepened to 35-40° and the crust became harder. When they were about 700 feet up, the weather deteriorated to a moderate snow fall and fog with visibility about 50 feet. They started to descend roped, but they unroped after several successful self-arrests. Lim stumbled and was able to stop himself but was dislodged by a small avalanche of the new snow on the crust. He stopped himself but was dislodged four or five more times, although his axe head was buried in the crust. As he was sliding down a snow chute that dropped over a cliff toward Lake Oesa, he drove the shaft of his axe hard into the snow after his next arrest. He was swamped by a pile of snow 18-26 inches deep, but was able to hold himself. (Source: Su-Chong Lim, The Chinook, Calgary Section of the Alpine Club of Canada, December 1977.)

Analysis: The hazard of fresh snow on a slick but only moderately firm crust was not recognized. The arrest might have been better if the boot toes had been used more effectively. If the party had been roped, perhaps more snow would have been dislodged by the sliding rope and made it impossible to stop himself. (Source: Su-Chong Lim.)