Strategy of formation of operating space in open pit mines based on cut-off grade control

Formation of operating spaces in open pit mines at structurally complex ore bodies should rest upon a cut-off grade strategy governed by varying economic and geological data. The managerial solutions on cut-off grades should be highly reliable in view of the stochastic nature of initial data, and should ensure flexibility of the design decisions on ultimate limits of open pit mines. Based on the implemented research, it is proved that the method of operating space formation in open pit mines should include prediction of change in the cut-off grades on low-lying horizons with regard to the current and anticipated market conditions. Decision making on an operating space in an open pit should embrace a number of scenarios: pessimistic, optimistic and long-range. Cut-off grade optimization should include the medium-term and long-term forecasts. In order to ensure admissible reliability of design choices, it is necessary to take into account complex project risks. Reliability of adopted cut-off grades is estimated as deviation of the actual values from the forecast. It is important to include probability of a scenario when the cut-off grade of ore-bearing blocks tends to the value of overburden blocks with a view to reducing the risk of underrunning design performance of an open pit mine.

Fomin S. I., Govorov A. S. Strategy of formation of operating space in open pit mines based on cut-off grade control. MIAB. Mining Inf. Anal. Bull. 2024;(11):165-179. [In Russ]. DOI: 10.25018/0236_1493_2024_11_0_165.

S.I. Fomin¹, Dr. Sci. (Eng.), Professor, e-mail: fominsi@mail.ru, ORCID ID: 0000-0002-0939-1189,
A.S. Govorov¹, Graduate Student, e-mail: s215078@stud.spmi.ru, ORCID ID: 0000-0001-9071-862X,
¹ Empress Catherine II Saint-Petersburg Mining University, 199106, Saint-Petersburg, Russia.

A.S. Govorov, e-mail: s215078@stud.spmi.ru.

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