*

ANM's assessment does not overturn shutdown order from

Brazil's

Labor Ministry

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Regulator's view could support Sigma's lawsuit against

government

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ANM's visit included visual assessment and documentation

analysis

By Fabio Teixeira

RIO DE JANEIRO, Feb 3 (Reuters) - Sigma Lithium's ( SGML )

waste piles at a Brazilian mine offer no "imminent

risk" and the country's mining regulator saw no need to shut

them down ‌during a visit last month, the agency told Reuters in

a statement on Monday evening.

The ANM's technical staff visited the mine on ​January 20, about

a month and a half after the piles were shut down by labor

inspectors ‍who warned of a "grave and imminent risk" to workers

and the local community.

The ⁠shutdown sent Sigma's shares ⁠tumbling some 30% after Reuters

reported on the inspectors' decision on January 15.

While ANM's assessment does not overturn the order from

Brazil's ‌Labor Ministry, it is a boost for the ​Toronto-listed

miner, as it could be presented as evidence in a lawsuit filed

against Brazil's government in early January, in which Sigma

seeks to overturn the closure of its ⁠waste piles.

The firm announced on Monday that ‍it was resuming ​mining

activities at its flagship Grota do Cirilo mine in the state of

Minas Gerais, and previously said that the shutdown of the piles

did not compromise its schedule for resuming ‍production there.

In documents filed to the Labor Ministry, the firm

previously said that losing access to the piles would cause

"significant operational and economic impacts, in addition to

jeopardizing the continuity of mining activity."

Sigma declined to comment on the matter due to "ongoing

administrative proceedings ... in different jurisdictions."

BRAZIL'S LARGEST LITHIUM MINE

Sigma's operation at Grota do Cirilo, its only productive

asset, is Brazil's largest lithium mine, with annual capacity ​of

270,000 ‍metric tons of lithium concentrate. It had been inactive

since October.

During the visit, ANM's technical staff made a visual

on-site assessment of the piles, and analyzed documentation

presented by the miner, ​the agency said.

"ANM technicians did not identify any geotechnical anomalies

indicative of an imminent risk of global destabilization of the

piles," it said in a statement.

While the agency found some issues during the visit, it

added that it saw no reason for the "adoption of precautionary

measures such as closure" of the piles "at the moment."

ANM has notified Sigma that its piles lack a superficial

water drainage system, but added that the issue is not

"associated with imminent ​risk" but is a regulatory failure by

the firm.

The agency also dismissed what labor inspectors said was a

"partial rupture" at one of the waste piles near a school.

According to ANM, the issue was a "localized erosion process" on

a pile that indicated "local ‍instability" but offered no

immediate risk to the local population.