Buried surface hoar failing under artificially created slab on West Grouse.

We looked at the Dec 4 buried surface hoar layer in two locations. If further loaded it will most likely be problematic. No signs of instability with the current 5 cm thick overlying slab in this area. When we added an artificial slab of an additional 10 cm of disaggregated snow that was allowed to sinter for 20-45 mins, we created propagating results. On a SE aspect at ~8,320', PST 96/100 end changed to PST 20/100 end with the loading of the artificial slab. Similarly on a NE aspect at ~8,060', PST 100/100 end changed to PST 9/100 with the loading of the artificial slab. At the SE aspect location the 12/4 SH was 4mm and partially decomposed but still allowed for easy shears in hand pits. At the NE aspect location, the 12/ 4 SH was 4 mm and well preserved.

Lots of new surface hoar on the surface that was 5 to 10 mm in size.