Pit results, Donner Canyon

With a level 1 AIARE course we toured into the Donner Canyon zone. Our day started with below average temps and cloudy skies but quickly the sun appeared and temperatures jumped to above average and we started to observe the solar effect. Tree bombs were prevalent throughout the day, roadways began to melt free of snow and we saw roller ball activity on any steeper pieces of terrain. Towards midday the cloud cover moved back in and around 1400 precipitation began again, starting in the form of graupel and quickly turning to large, fat snowflakes. Around 6300' on a N aspect we dug down 125cm to observe the new snow load. We found 72cm of new rightside up snow sitting on top of a facet crust combo with buried surface hoar at the bottom of this sandwich. Our first compression test yielded CTH SC 77cm down on this buried 8 - 10cm surface hoar layer that also contained graupel. On our second compression test we got CTM SC 32 cm down within the new snow. We conducted 3 compression tests and were able to get our CTH x2 and CTM x1. From here we moved on to an extended column test, hoping to target this buried weak layer. Upon performing our extended column test we got a ECTP30 77cm down, we repeated this test and received the same result a second time. Additionally our group was feeling motivated and were curious about the rutschblock test so we began to dig our block and received a RB1 score, before we finished isolating the block that failed on this weak layer. Worth noting was our positioning on a small piece of due north facing terrain that is tucked into the canyon and fairly sheltered. 

On our ski out the access road we noted a crown across on the lake run terrain, it appeared to be a few feet deep and 100' wide. We were not close enough to glean a large amount of data about this incident but it was not noted on the way up in the morning so we suspected that it had happened during the day.