Brazil’s audit court is likely to put the sale of Braskem SA on hold because of an environmental crisis involving the company in the northeastern state of Alagoas, according to a person with knowledge of the matter.

Before being sold, the petrochemical producer will have to determine damage costs related to a salt extraction project that caused the soil to collapse in Maceio, the state’s capital, forcing roughly 50,000 people to move out of their homes in 2018, the person said, asking for anonymity because the matter isn’t public.

Braskem shares fell as much as 1.9% in Sao Paulo to a session low before trading was halted. Bonds and depositary receipts also dropped in New York.

The audit court’s decision is expected to come in the next few weeks. It affects the sale because state-controlled oil producer Petroleo Brasileiro SA is Braskem’s second biggest shareholder. Petrobras has the right to purchase the stake that leading shareholder Novonor wants to sell.

Braskem and the audit court known as TCU did not immediately reply to emails seeking comment.

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Before part of Braskem is sold, the stakeholders need to calculate the cost of the damage and explain how the problem will be fixed, the person said. The concern of the audit court is that, if such costs are not previously estimated, Petrobras may end up footing the bill.

--With assistance from Cristiane Lucchesi, Vinícius Andrade and Maria Elena Vizcaino.

(Updates with market impact in third paragraph.)