CHENNAI: The operation to safely remove about two tonnes of ammonia stored at the seafood processing unit in Kannigaipair village near Periyapalayam, where an ammonia gas leak last month claimed 18 lives, will start on Saturday morning.

By Friday evening, a 500-metre exclusion zone has been enforced, traffic has been diverted, and nearby factories, schools and anganwadi centres have been asked to remain closed during the operation. Authorities said there are no residential buildings within a 300-metre radius and urged residents not to panic or gather near the factory to witness the operation.

Tiruvallur Collector S Kavitha inspected the factory on Friday and reviewed the safety arrangements ahead of the ammonia transfer operation. She said around 400 tonnes of processed seafood stored at the unit had already been shifted to warehouses, while all migrant workers from Odisha, Assam, Kerala and West Bengal, who had been staying in relief camps, have safely returned to their native states.

The Collector said experts from the National Disaster Response Force (NDRF), Fire and Rescue Services, Madras Fertilizers Limited (MFL) and Chennai Petroleum Corporation Limited (CPCL) had been consulted to ensure the safe handling of the ammonia.

The gas transfer is scheduled between 8 am and 5 pm. If the operation is not completed on Saturday, it will resume on Sunday.