Sigma Lithium batteries pose no imminent risk, says ANM.

247 - The tailings and waste material piles at Sigma Lithium, located in a mine in the interior of Minas Gerais, do not present an imminent risk of collapse, according to a technical assessment by the National Mining Agency (ANM). The conclusion was released on Monday night (3), after an inspection carried out at the site in January, and comes weeks after the Ministry of Labor ordered the closure of the structures due to alleged risk to workers and the surrounding community.

According to the ANM, a technical team was at the Grota do Cirilo mine on Monday (20), about a month and a half after the closure promoted by labor inspectors, who had classified the situation as a “serious and imminent” risk.

The decision by the Ministry of Labor had a direct impact on the financial market. After the announcement of the ban, on Wednesday (15), Sigma Lithium's shares, listed on the Toronto stock exchange, fell by about 30%. The mining company, however, reported that the shutdown of the stockpiles would not compromise its production resumption schedule.

Although the ANM's assessment does not revoke the Ministry of Labor's order, the mining regulatory body's position strengthens the company's legal strategy. In early January, Sigma filed a lawsuit against the Brazilian government to try to overturn the injunction, and the agency's technical report could be used as evidence in the process.

In an official statement, the ANM (National Mining Agency) detailed that it conducted a visual inspection of the tailings piles and analyzed technical documents submitted by the mining company. "ANM technicians did not identify any geotechnical anomalies indicative of an imminent risk of overall destabilization of the piles," the agency stated.

The regulatory body acknowledged the existence of some nonconformities, but stressed that they do not justify, at this time, the adoption of more severe measures. "Conditions that would justify the adoption of precautionary measures of prohibition have not been found at this time," ANM reported.

Among the issues raised, the agency notified Sigma Lithium about the absence of an adequate surface water drainage system for the fuel stocks. According to the ANM, this is a regulatory failure, but one that "is not associated with imminent risk."

The agency also disputed the labor inspectors' assessment of an alleged "partial rupture" in one of the tailings piles located near a school. According to the ANM, what was identified at the site corresponds to a "localized erosion process in one of the banks of one of the piles, with indications of local instability," without posing an immediate risk to the population.

On Monday (3), Sigma announced the resumption of mining activities at its main unit, Grota do Cirilo, which had been inactive since October. The complex is the company's only productive asset and houses the largest lithium mine in operation in the country, with an annual capacity of around 270 tons of concentrate.

In documents previously submitted to the Ministry of Labor, the mining company had warned that the loss of access to the tailings piles could generate "significant operational and economic impacts, in addition to compromising the continuity of regularly licensed mining activity." Contacted for comment on the ANM's statement, the company has not yet responded.