Weatherly progresses with Tschudi dewatering plan

23rd July 2018 By: Marleny Arnoldi - Deputy Editor Online

Aim-listed copper miner Weatherly International expects production levels at its Tschudi copper mine, in Namibia, to normalise by December, following a massive water ingress on May 11.

Weatherly has since progressed with a recovery plan that entails dewatering the mine.

The recovery strategy and expenditure plan will require N$14.3-million. Work is under way to increase pumping capacity to lower and stabilise the water levels in all pits and allow mining operations to regain access to the ore.

Weatherly Namibia CEO John Sisay remarked that, with the necessary financial assistance from Orion Mine Finance, the company is confident of implementing the recovery plan and restoring normalised production levels at Tschudi.

The recovery strategy is based on a 12-week delivery and includes water abstraction, related to all equipment and infrastructure required to reduce water levels in the pits and to pump it into the canal that runs along the footwall of the pit; water discharge, dealing with moving the water away from the openpit mining area and discharging it at re-injection areas which have been approved by Namibia’s Department of Water Affairs; and implementation of various supporting actions to improve post-recovery water management.

So far, abstraction capacity has been increased from 1 400 m3/h to 3 000 m3/h through the rental of additional diesel-driven pumps and the installation of 1 800 m of high-pressure high-density polyethylene pipelines.

A canal and settling dam are now fully commissioned to handle the water discharge, with the canal capable of handling more than 6 000 m3/h.

Distribution from the settling dam is maximised, with current installed infrastructure at 2 000 m3/h to direct water to various discharge points through a stormwater pond, with the balance of the water overflowing the settling dam back into the aquifer.

Additional infrastructure is planned to increase distribution by 2 000 m3/h from the settling dam by the end of July.

Significant progress has been made to design, cost and implement a significant upgrade of the dewatering infrastructure.

The system will be upgraded to increase the abstraction and discharge rate to a nominal 3 000 m3/h through a predominantly electric grid-power system.

The system will be developed in three phases at an estimated capital cost of N$44-million. This will include an additional grid-power substation to increase power supply to Tschudi by 4 MVA to 12 MVA.

Management remains confident in the future financial viability of the Tschudi mine.