Persistent slab near Ledge

Aspect: North west at treeline. Deep wind slab. A party of 3 ahead of us was breaking trail across deep wind slab and remotely triggered a release about 30 meters above them. I was about 100meters in back of them and felt and heard a very large whomp as the slope settled. The party was traveling fairly close to one another but luckily only one person was caught and carried down 20 - 40 meters. No injuries reported Snow quality below ridgeline was great. This location has been is known to be persistent and wind slab.