Skied this South Facing LCC Couloir at daybreak. The Line has a steep, treed headwall that funnels into a long, shallow chute. My partner and I both had radios, so I was hopeful that my partner would be able to radio me as I skied if anything was amiss, but when he went to turn on his radio, the battery was dead, so that was an issue. I skied the upper headwall and the chute with speed; nothing cracked and the snow felt stable. I skied past a few point releases and smaller slides, but nothing was moving around me. I skied a long way, probably 1500-2000 vert before coming to a stop on an older debris field from another chute that funneled in. I was lucky enough to turn around and see the plume of snow coming down the line from behind me. I beelined for the bushes, the only high ground I could gain. The slide rushed past me and kept going for a while. after it finally stopped, I called my partner above; he stated that he saw a small slough behind me halfway down the chute, but nothing big. I can only imagine I set off a slough which then picked up speed and ended up entraining a lot more snow. All the south facing couloirs in LCC are slide paths for a reason, and this time, this one slid on me.