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Underground stoping

This article provides insight into one of the upcoming Underground Engineering tools, MineSight Stope (MSStope). Specifically aimed at underground stope mining, the tool will handle tasks such as block economic value (BEV) computation, stope slicing, scheduling, and reserve reporting. MSStope will provide planners with a quick, easy-to-use tool for preliminary stope design, conceptual level scheduling, and sensitivity analysis.

The primary input required by MSStope is the block model for the project in question. Apart from the usual grade items contained within, several new items need to be defined in order to store output generated by the MSStope computations. These include an item to denote different mining areas, a flag to denote which blocks are included in or excluded from stoping, an item to store the BEV, and an item to record stope numbers that result from slicing the mining area.

Once these items have been defined and stored, we create a model view object for the block model, which can then be loaded in MSStope, and each of the sections within the tool can be configured by setting up the parameters contained within. The tool contains three main sections – Stope Boundary, Slicing, and Scheduling – which we shall examine in further detail.

1) Stope Boundary: This section is used to add in block model items, define minimum stope dimensions (in number of blocks), and input economic parameters, which then allow MSStope to compute the final BEV for each block in the model. Whether the block model is to be processed in its entirety or only in part can also be customized by defining the area of interest. In its current state, MSStope utilizes the MVN (Maximum Value Neighborhood) algorithm to search for the best possible combination of blocks that will yield maximum profits. Other algorithms are expected to be made available with future releases of the tool.

Figure 1: Underground stope shape, showing crown pillars (blue), stopes (red), and ribs (orange).

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Figure 2: Block Model setup within MSStope.

Figure 3: Defining variable and constant economic parameters.

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2) Slicing: This section contains settings related to slicing the mining area into stopes, as well as generating reserve reports. If working with multiple mining areas, each area may be sliced differently to produce multiple regions or sub-levels, by specifying different dimensions, azimuths, and crown pillar heights for each area. Once completed, reports on tons and grades for sliced stopes can be generated. The reporting section is similar to the ARC Reporting tools seen in other areas of MineSight, and allows for customized report generation with user-defined fields.

Figure 3: Reporting reserves from sliced stopes.

3) Scheduling: This section is responsible for providing scheduling information for the stopes; i.e. the availability of stopes during certain periods of time, and the order in which they should be mined to maximize efficiency and maintain profitability. Four different scheduling approaches are available, and inputs relating to time periods, stope development, material processing etc. need to be provided. Scheduling is performed by simulating the mining process day by day within each time period for all the available stopes. As with reserves, customized scheduling reports can then be generated.

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Figure 4: Scheduling reports provide information on which stopes should be mined during which periods.

After setting up and running MSStope, we can check the results of the computations by querying blocks from the block model and examining the new items defined at the start – these will now be populated with values.

MSStope is gearing up to be a revolutionary addition to the Underground Engineering toolset in MineSight, and its release as part of a future MineSight update will afford you great flexibility and control in the design and scheduling of underground stope mining, at a conceptual level of detail.