The experiences from the recent 3 years at Springvale Mine have highlighted once again the importance of understanding the geological structure at a mine site. Springvale Mine previously had a history of difficult roof conditions, although not clearly linked to geological structure. From mid 1998 a series of complex strike slip fault structures were encountered, one set running with and along the commencement of the 404 Panel gateroads. The unexpected faulting, its critical location, and unknown extent had a serious impact on panel development and business performance. Even the most carefully constructed business plan and budget is quickly damaged by an unwelcome geological surprise.