What happened

Diluted tartaric and sulphuric acids leaked from an anodising surface-treatment bath and were contained in secondary containment. During maintenance, workers pumped the retained liquid into a 1,000-litre vessel that already held about 100 litres of concentrated sulphuric acid. A reaction with the pumped material or impurities generated orange vapour, prompting evacuation and an emergency response. Drain outlets were secured, the reaction stopped at about 17:00 and approximately 300 litres of acidic effluent remained contained for specialist disposal. ARIA attributed the event to use of a non-empty recovery vessel and failure to follow the pumping procedure strictly. No off-site release or injury was reported. The map position is approximate to Saint-Brevin-les-Pins because the public record withholds the operator and precise address.

When cited sources give different casualty, damage or spill figures for this event, they’re reported side by side above rather than merged into one number. See how confidence levels work.