The French high commissioner to French Polynesia has acknowledged that pollution with heavy metals continues to be a problem on Hao atoll.
Rene Bidal said the clean-up of the former French military base had involved the removal of hydrocarbon residues.
He told Tahiti-infos that his office was in talks with the government and the local council on how to deal with the heavy metal legacy.
Hao has been earmarked for the region's largest fish farm but the project of the Chinese company Tahiti Nui Ocean Foods keeps being delayed.
Earlier this year, the company said 240 containers of material would arrive by April to launch construction of the plant which was said to cost about $US320 million.
On local television this week, a senior government minister Jean-Christophe Bouissou said there was no impediment for the project to go ahead.
He said he won't criticise an investor who is spending $US1.5 billion in private money.