Discharge from Atalco alumina refinery into Mississippi River prompts environmental concerns

A pattern of persistent breaches

Located around 45 miles west of New Orleans, Atalco converts bauxite into alumina for aluminum production. Even so, even with this critical industrial role, it has faced heightened scrutiny for repeated toxic discharges and workplace safety lapses.

Aerial images taken on October 21, 2025, showed white alumina residue and swirling discolouration beside the refinery docks. Environmental advocates said the discharges resembled previous contamination events. "For years, we have watched Atalco dump into the Mississippi River. They are not investing enough in their own operation to prevent this product loss," said Scott Eustis of Healthy Gulf.

The plume reportedly came from a regulated outfall pipe, with monitoring showing extreme alkaline levels. State filings revealed pH spikes up to 13.4 for nearly 144 hours in September, far above the seven-hour monthly allowance.

Environmental risk and corporate pushback

Atalco attributed breaches to weather-related "plant upsets" - temporary malfunctions caused by operational stress - though official data showed minimal rain. The Louisiana Department of Environmental Quality (LDEQ) confirmed ongoing investigations and noted that erosion from outflow pressure could also affect river colour.

The company has allegedly exceeded discharge limits in 25 of the past 27 months, prompting calls for higher fines. Activists argue only strong financial penalties will curb what they view as habitual non-compliance. "We press LDEQ to increase Atalco's fines until that economic signal shakes some sense into the company," Eustis said.