Por: Patricio Vergara Lara, Redco Mining Consultants USA y Gino Espinoza Guzmán, Redco Mining Consultants Perú.

Abstract

Every mining project study, at some stage of its engineering process, faces the critical discussion of selecting and justifying its production capacity.

In the early 2000s, Brian Hall developed a methodology known as the Hill of Value (HOV): a 3D surface representation combining production capacity and cut-off grade, and their relationship to the project’s economic return. 

The concept was widely accepted worldwide because it not only provides an easy-to-understand executive-level representation that supports the project’s selected capacity, but also illustrates its relationship with the level of selectivity required from the deposit through the cut-off grade. However, one of its weaknesses lies precisely in its simplicity: the recommendation of a fixed cut-off grade that remains constant over time.

To improve this aspect while preserving its other advantages, Redco Mining Consultants (Redco) applies a methodology that combines the Hill of Value concept with Kenneth Lane’s algorithm. This approach integrates production capacity selection, reflected through a mine macro-sequence, with an optimal cut-off grade strategy that decreases over time, improving the economic results projected by the Hill of Value surface.

This paper presents the proposed methodology and quantifies the improvements achieved in selective underground mining projects.