Mallard Lodge area

Notable event with no involvement at Mallard Lodge today. I was guiding a group of 8 guests down a short 150m vertical supported open alpine-ish slope to 35 degrees. The group was spread out so only 1 or 2 people were on the slope at the same time. The 7th skier remotely triggered the deep persistent slab on an adjacent convex slope from 20m away. 3 other sz 2 avalanche simultaneously initiated on other nearby slopes as far as 200m away. All avalanche were of similar depth with rocky/convex terrain start zone configurations. The avalanche closest to the ski line actually took 2 of the closest ski tracks with it. Luckily no one was involved. Of note, we had no agenda today. We were running a conservative program and just trying to ski supported ski lines while managing our exposure to overhead hazard. Today was our fifth day in the area. We were experiencing recent loading (20cm of new snow and moderate SW winds), warmer temperatures and weak (facetted) rocky mountain snowpack. This new load was apparently all that was required to trigger the deep persistent slab with a light load, something that will require more monitoring in the future. We had just dug a rutshbolck test down to ground (HS 200cm) on a nearby slope with no results (RB7). This goes to show that test results are not always representative of the conditions. A pretty good wake up call and luckily no involvement.