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Show this one in the history of the area's occupation. COMMENTS These houses were right at the foot of steep, open slopes. When the right combination of snow conditions ( 33 inches new snow on a hard crust) arrived, the inevitable happened. Destruction of vegetation by smelter fumes and fire probably contributed to this disaster, both by clearing the avalanche paths and by facilitating wind- drifting on the ridges. No. 57- 3 LOOKOUT PASS, MONTANA 6 February 1957 WEATHER FACTORS During the first week of February, 1957, there were several snow slides in the St. Regis Canyon region. For a period of two weeks preceding this slide activity, the temperature ranged from 0° to 30° below zero. In the first few days of February, the temperature rose to a high of 30° to 40° above zero, and heavy wet snow began falling. Early Wednesday morning, 6 February , a Northern Pacific freight train was making its run from Wallace, Idaho, to St. Regis, Montana, through Lookout Pass. By this time the temperature was 30 above and the wind velocity was southeasterly ten io fifteen m. p. h. ACCIDENT SUMMARY At approximately 9: 00 a. m. the train was passing through an area one mile east of the Pass ( elevation 4400 feet) when an avalanche released on a steep ( 60%) slope three hundred feet above the tracks. The depth of the snow pack at the fracture varied from four to six feet. When the engineer saw the snow rushing down toward the tracks, he opened the throttle and tried to plow through the slide. But it was only seconds before the avalanche picked the lead diesel off the tracks and carried it seventy- five feet downhill. The rest of the train stayed on the tracks and was partially buried by the slide. Luckily, no one was injured. The avalanche had virtually cleaned the hillside of snow; deposition on the tracks was nearly five hundred feet long and varied in depth from ten to twelve feet. After the train had been pulled from the slide, the slide moved again to fill the space that had been occupied by the train. COMMENTS This slide came from the same weather pattern that produced the Wardner Idaho, accident. See No. 57- 2. 30 |