At least one Fire Service crew was remaining overnight at the scene of an acid spill on a manufacturing site in the Whakatu Industrial Park between Napier and Hastings.
Most Napier and Hastings station resources were involved in the emergency at the peak at the UHT milk and fruit bottling plant of Etika Dairies, where the alarm had been raised at 2.57pm.
Fire Service Central Communications shift manager Murray Dunbar said nine units were at the scene most of the afternoon and early-evening, as crews worked to contain the leak.
One officer said it was a mixture of two chemicals which was "absorbed" in a mopping process as crews worked to stop the mix entering any waterways.
The Johnston Way plant were workers were evacuated, but workers at other nearby sites were able to continue working, but were advised to close windows.
A stand-by crew remained at the scene late last night, and an officer said other crews would return to the site in the morning to assess the situation and investigate.
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