Alrosa starts drilling freezing holes for construction of Mir-Gluboky mine

MOSCOW. July 29 (Interfax) - Alrosa-Spetsburenie, a division of Russian diamond giant Alrosa , has begun drilling 84 freezing holes at the construction site of the Mir-Gluboky underground mine, a project to restore production at the flooded Mir mine, Alrosa said in a press release.

There are plans to drill 42 holes at the skip shaft and 42 at the cage winding shaft. The holes will be 550 meters deep.

"There will be two stages of construction. We have now begun the first. Alrosa-Spetsburenie is drilling [holes] at a depth of zero to 50 meters. The second stage is drilling at a depth of 50 to 550 meters," Alrosa-Spetsburenie general director Kirill Degtyarev was quoted as saying in the press release. The work will be completed in the first quarter of 2025, he said.

When the drilling is completed, the holes will be injected with a cooling agent that will create an ice wall to prevent penetration of ground water from the water-bearing formation and enable mine builders to safely do their work.

Alrosa began preparations for the construction of the Mir-Gluboky underground mine at the end of 2023. The plan to build the skip and cage winding shafts using a special way to freeze groundwater was developed by Alrosa's Yakutniproalmaz institute and approved by state expert review office Glavgosexpertiza in May 2024.

Alrosa CEO Pavel Marinychev said earlier that the construction of the Mir-Gluboky mine will cost 121.5 billion rubles.

The Mir deep mine was flooded in 2017 when water from the depleted open-pit mine above it broke through, killing eight of the 151 workers who were in the flooded area of the mine. Mine workings and equipment were completely destroyed and two levels were flooded.

Ore at the Mir deposit has a high content of high quality diamonds and the Mir mine accounted for over 10% of Alrosa's output before the disaster.