Assessments confirm integrity of main hoisting shaft at Prieska project

JOHANNESBURG (miningweekly.com) - Detailed visual and mechanical inspections of the barrel and steelwork of the Hutchings shaft at Orion Minerals' Prieska zinc/copper project, in the Northern Cape, have confirmed that the shaft steelwork and wall integrity have been well preserved.

The shaft has been inoperable and submerged for 26 years.

Orion intends to establish new mining operations to continue the extraction of the remaining Copperton deposit, a volcanogenic massive sulphide-style deposit, with significant residual potential.

Shaft inspections are being conducted as part of the ongoing mine feasibility and environmental studies at the Prieska project.

The Hutchings shaft is intended to be recommissioned as the main means of hoisting rock, people and materials and as the primary means of ventilation intake.

The results of the inspections show that refurbishing the existing shaft for future use is a realistic and viable option that can be considered in ongoing bankable feasibility studies.

A second stage of inspection will involve obtaining video footage of the shaft steelwork and walls to a depth of at least 200 m below the accumulated water level.

A detailed civil and structural assessment of the concrete headframe will be conducted once winder selection and proposed placement is completed.

"The shaft refurbishment plan forms a significant part of our strategy to take advantage of existing infrastructure which will reduce the capital expenditure burden on the Prieska project build.

"The existing shaft infrastructure is sufficiently-sized so that we are free to optimise mine production rates to the Joint Ore Reserves Committee-compliant Mineral Resource estimates we end up delineating. This gives us great design latitude to make the most of what remains at Prieska," Orion MD and CEO Errol Smart commented.