At 11 am Monday 8 September 1997, the successful detonation of the 5/9 Mass Blast at Pasminco - Elura was signified by the subsiding of Mt Kevin' (a 15 m high earth fill mound). The blast was in response to earlier mine subsidence, which holed through to the surface affecting future stability of underground workings. The blast was a first for Elura which fires small tonnages regularly to avoid rapid oxidation of the ore. This paper discusses the strategy and the considerable planning that went into Elura's first blast of this magnitude in order to succeed first time round.