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Mining of the Basal Reef at Jeanette Mine, is typically complicated due to an overlaying Khaki Shale (shale) that has unfavourable rock engineering properties. Shale has always been either left underground or mined as part of the orebody. The first approach can only be applied in areas where the quartzite beam (directly above the Basal Reef and below the shale) is of sufficient thickness to support the shale in the hanging wall. This method is known as undercutting. Alternatively, open stoping can be applied in areas where the shale and the Basal Reef is extracted concurrently and sent to the mill as diluted ore. Alternatively, a resue stoping method can be considered in areas where undercutting cannot be done, due to a thin quartzite middling. Resue stoping involves stowing or packing of the shale into the mined-out area and is not included as part of the hoisted rock. In the past, resue stoping was done by hand packing, which is unsuitable for a modern mine. As such, two mechanised resue stoping methods can be considered, namely; Longhole Resue Stoping and Rib Cutting Resue Stoping. Rib Cutting Resue Stoping utilises a continuous miner (“CM”) to remove the shale in a first pass, extract the reef during a second pass and backfilling the mined-out rib with shale. The use of a CM will significantly improve the extraction/mining rate, sidewall stability, backfill placement, dilution and overall safety. Longhole Resue Stoping utilises strike drives from where longholes are drilled into the shale and the reef in an up-dip direction moving on retreat. The shale is blasted with sufficient force into the mined-out area behind it, compacting it. The reef will be loaded by Load Haul Dumper (“LHD”) or dozer. It was determined that Rib Cutting Resue Stoping is more effective than Longhole Resue Stoping due to a higher extraction rate, lower dilution, reef loss reduction and improved shale sidewall stability. The operating angles and equipment height limits the application to only 51% of the available reef at Jeanette mine with favourable dip and thickness. Longhole Stoping can navigate hard rock, shale and increased dip angles; it can be applied to 91% of the available ore deposit. Longhole Resue Stoping and Rib Cutting Resue Stoping should both be considered as suitable stoping methods for Jeanette. / Thesis is submitted in partial fulfilment for the degree of Master of Science in Engineering to the Faculty of Engineering and the Built Environment, School of Mining Engineering, 2018 / XL2019

The overall objective of any geotechnical mine design procedure must be to maximize the extraction of the ore reserves while maintaining the integrity of the working areas. At the McLellan Mine the cut-and-fill mining method was first adopted. This decision was made for flexibility in the size and shape of the mine openings to allow for the variability in width and grade of the ore zone. As a result the geotechnical design of the cut-and-fill stopes necessitated investigations to evaluate the character of the rock mass with regard to the hydrogeology, lithology, structural geology, rock strength and rock mass ratings at the site and to assess the in-situ stress conditions. In addition, the character of the backfill material had to be estimated prior to detailed testing. Based upon these parameters two dimensional finite element analyses were completed, the sill pillar and the two stopes were designed. Finally, remedial rock reinforcement was recommended for suspected unstable spans. / Applied Science, Faculty of / Mining Engineering, Keevil Institute of / Graduate