February 8, 2021 – ALROSA has launched a project at the tailings dump of the Processing Plant No. 14 of the Aikhal Mining and Processing Division (Aikhal Division) to further improve its reliability and reduce operating costs.
The package of works provides for the creation of a network of wells (injection, confirmatory and observation) for colmatation, i.e. reducing the permeability of the base of the tailings dump – a hydraulic structure (HS) where tailings of diamond processing, which is a mixture of finely ground waste rock and water, are stored.
Colmatation is the process when special substances are injected into holes and cracks in rock to reduce water permeability. In this project, a bridging agent is Akvidur ES-E, polyurethane resin that binds and precipitates host rock particles to clog holes and cracks in the rock mass.
“Colmatation of filtration paths in the area of the left and right walls of the settling pond will make it possible to form a stable stair-step zone with low permeability. This will further increase the reliability of the hydraulic structure and reduce the cost of its operation by reducing the volume of pumped drainage water from the storage pond to the settling pond. Completion of works is scheduled for Q3 2021,” said Sergey Arsentiev, Deputy Chief Engineer for hydraulic structures of the Aikhal Division.
ALROSA pays priority attention to improving the reliability and safety of tailings dumps and other hydraulic structures. In 2020, the Company’s investments in the maintenance, modernization and operation of hydraulic structures of the tailings dump at Processing Plant No. 14 amounted to about RUB 230 million.