The Southern Province Government in New Caledonia says a mining waste disposal pipe poses no threat to the environment.
Activists are protesting about the Goro Nickel mining company who is building an underwater pipe that will dispose neutralised liquid waste into the lagoon at the Havannah Channel.
They say the pipe will go through an area of underwater stalagmites that are unique in the world and the pipe could destroy them.
The Southern Province administration's head of environment, Christophe Chevillon, confirms that the area is special, but says the pipe won't do harm.
"It's only one part of a grouping of submarine vents, which was concerned by the Goro Nickel pipe project. And I discussed that with the people of environment at Goro Nickel. We decided to move the traject of the pipe to avoid this submarine vent. Today, there's no problem with this point"
Christophe Chevillon, the head of the southern province environment department in New Caledonia.