This paper presents the results of a monitoring program to characterize the blast damage experienced in weak rock masses extracted by underground sublevel stoping methods. Triaxial geophone arrays were used to monitor blast attenuation and extensometers were used to measure hangingwall deformations during stope extraction. The blasting events were monitored and the vibration data were analyzed using the Holmberg-Persson criteria for blast attenuation. A comprehensive analysis of the measured vibrations was completed. This was followed by the development of predictive tools that can be used to reduce blast damage during future underground extractions within weak rock.