On the afternoon of 12/21/06 at approximately 1:20 pm a rock burst in the 4000-226E stope occurred. By 1:35pm all personnel underground were accounted for & OK. Msha was notified at1:35 pm PST. The crew in 226 stope was withdrawn. On 12/22 the stope was examined. Minimal damage along approx 100' of footwall from face to raise. Area was scaled & slushed & bolts installed.