Bullmoose Falls

Incident

Group Size

3

Terrain Trap

noTrap

Group Activity

snowshoeing

Number Involved

1

Snow Depth Trigger Point

average

Terrain Shape Trigger Point

concave

Number Partly Buried Able Breathing

1

At Bullmoose Falls, a horseshoe shaped canyon near the Bullmoose mine. Party of 3 snowshoed to the falls. Deep trailbreaking with some settlement and whumphing; loose facets layer evident. Two people went behind the falls, out of sight of the third person. The third person started a diagonal ascent of a 20 m high slope to the right of the falls (looking up). The person took a few steps at the base of the concave slope, and the slope released at the top and slid over them. Their snowshoes were trapped, and the snow knocked them over, burying them so that they were lying on their back with their head downslope (slope was 10 degrees under the victim). The snow buried the person so that only their head and one arm were visible. As the slide was happening, the person yelled 3 times, alerting the other two, who came over immediately and dug the person out. There was about half a meter of debris over the chest of the person, but the snowshoes were buried deeper because they were already half a meter deep from trailbreaking. Slope that slid was 20 m X 20 m, concave up to 35-40 degrees at top, and 10 degrees at the trigger point. Bed surface was variable: midway through the facet layer, 10 cm of old crusty snow right at ground level, or ground itself. It looked like 20 cm of facets with 50 cm of soft slab above. Surprising things to me about this incident were the amount of debris from a small slope, and the sensitivity of the slope to triggering (right at the base of the slope with only a few steps). The debris was relatively soft and easy to dig, which made rescue fast. The person reacted well by yelling and raising their hand.