Samarco used 95% of the sandy tailings generated at its Concentrator 3 of the Germano Complex, in Mariana (MG), in the de-characterization works of the Germano dam, between January and February this year. The percentage represents a volume of approximately 1 million tons of waste. The geotechnical characteristics of the material meet the project's assumptions and criteria, contributing to the company's sustainable practice.

The works to de-characterize the Germano dam are at an advanced stage, with 75% of the interventions completed. Samarco's Project Coordinator, Marcelo Fortes da Silva, explains the application of tailings in interventions.

“One of the stages of dam de-characterization is to eliminate the accumulation of water in the reservoir. We are using sandy tailings to correct the topographic grade, directing the flow of water to the surface drainage system and eliminating any accumulation of water in the reservoirs. Furthermore, we use tailings to reinforce structures”, highlights Silva.

Samarco also used sandy tailing in the de-characterization works at Germano Pit, which was completed in July last year, before the scheduled deadline (October 2023) in the commitment agreement signed with Federal and State agencies.

Among the benefits of sandy tailings, we pinpoint homogeneity and better permeability to guide the flow of water to internal drainage. According to technical planning, the forecast is to use 16.7 million tons in the works to de-characterize the dam and protect the slopes of Germano Pit, in the period from 2023 to 2029. The rest of the sandy tailings is disposed of in the (PDER) Alegria Sul Overburden and Tailings Disposal Pile.

“Just as important as allocating the tailings is avoiding the purchase of new inputs, such as sand and stone used to perform dam de-characterization services. For each ton reused, the purchase and transportation of these inputs is avoided, in addition to the reuse of natural resources. It represents an exponential gain” explains the General Manager of Project Execution, Eduardo Moreira.

Samarco's innovation specialist, Marcos Gomes Vieira, states that other projects are being developed to use sandy tailings as an input for the manufacture of concrete and the application of ultrafine tailings (mud) in ecological paving projects. “But in addition to providing alternative destinations for the tailings, we are working at the source to reduce its generation, with process optimizations that increase the efficiency of the processing plants”, highlights Vieira.

Photo: decharacterization of the Germano dam.