A rock burst was discovered in the 4000-226 rasie and stope. It showed up on the rock burst monitoring system on Saturday 10-23-04 at approx. 11:30 am. No one was owrking at the time. Damage to the raise occurred at stope level (26 sets up form the sill) and 11 sets above (66 feet). Slight damage occurred int he east stope.