Overview
- A roughly 100-foot-wide slab ran about 400 feet down Castle Peak on Feb. 17, burying a 15-person backcountry party of 11 clients and four guides and killing nine people.
- Partially redacted coroner reports released in early August confirmed all nine victims died of asphyxia from burial by snow and left questions about toxicology and other injuries unanswered.
- Technical reviews by the Sierra Avalanche Center and the National Avalanche Center found guides led the party below avalanche terrain in dangerous conditions and that the combined group size increased the chance of triggering the slide.
- Several people wore avalanche airbag packs that did not deploy, survivors dug out some companions before professional teams reached the scene, and all bodies had been recovered by Feb. 21.
- Nevada County investigators have completed their probe and sent findings to prosecutors, and a criminal negligence investigation remains active with potential consequences for the guiding company and backcountry safety rules.