Vancouver-headquartered Trevali has suspended its production and cost guidance for its flood-hit Perkoa mine, in Burkina Faso, as search and rescue efforts to locate eight missing miners continue.

CEO Ricus Grimbeek, who travelled to the mine site with other senior company officials, said on Thursday that the company had received support from various government agencies and the extended mining community, which had volunteered highly skilled personnel and equipment for use in the search and rescue.

“The health and safety of our workers is our top priority, and all efforts are being made to extend the search into the lower levels of the Perkoa mine. We will not cease our efforts until we have found our missing colleagues,” he said.

Intense rainfall at the weekend resulted in a flash flood that breached protective berms surrounding the openpit at Perkoa. About 125 mm of rain fell in less than an hour, outside the usual rainy season. Water entered the openpit and subsequently went into the underground mine. As the water entered the mine, electricity and communications underground were lost.

After the flooding stopped, the water level in the mine settled at about Level 520. The search above this level was completed by April 16. The mine depth is to Level 710. Communications have been re-established to Level 520 and electrical power re-established to Level 430.

"The health and safety of our workers is our top priority, and all efforts are being made to extend the search into the lower levels of the Perkoa mine. We will not cease our efforts until we have found our missing colleagues,” said Grimbreek.

Further, Trevali said that all underground mining and surface activities would remain suspended at Perkoa for the foreseeable future. This would likely result in reduced zinc production in 2022 for the company, relative to its previously released guidance.

“The requirements for infrastructure refurbishment and construction linked to repairs and rehabilitation at the mine remain unknown, as does the timing for a potential restart of mining and processing activities. Underground development activities will only recommence once it has been determined that this can be done safely.”