A Fire and Emergency New Zealand spokesman said a crew from Edendale, two from Invercargill, two from Mataura and one from Wyndham were called to the scene of a nitric acid leak about 10.30am.
Crews were at the scene for five hours and helped with decontamination, the spokesman said.
There were no injuries at the site, he said.
Fonterra lower South Island operations general manager Richard Gray said the cause of the leak was identified quickly, which was caused by a leaky valve.
A police spokeswoman said police were not sent to the scene.
