An independent investigation is wanted into sedimentation at a new mining project in the Morobe province of Papua New Guinea.
Initial environmental assessments conducted in 2006 by the Morobe Mining Joint Venture failed to predict the damage from sedimentation.
Radio New Zealand International reports an estimated 50 million tonnes of sediment from erosion has clogged the river system there, causing significant problems for the people living off it.
Responding to mounting local concerns, the mine operator has commissioned a new study to determine the extent of the problems.
Project manager Adam Wright admits sedimentation has been higher than expected and says the mine operator is open to rectifying the problems caused by it.
However, Bulolo MP Sam Basil is pushing for an independent assessment of the project's environmental impact.
He says action must be taken by the government to avoid difficulties that have plagued other big mining projects in the Highlands.
Mr Basil says the MOA governing the project does not give full protection for the communities worst affected by the sedimention.
Apart from the destruction to marine life and the impact on gold panning in the area, he says the project is going to affect crucial development in the province such as a tidal basin project at Lae Port.
Meanwhile, Nakuwi Landowners Association president Rex Mauri, recently expressed frustration that his people have been left out of economic and other spin-offs related to the venture.
Since this warning, Harmony Gold is understood to have begun awarding a number of small contracts to resolve this outstanding issue. But potential unrest in the Hidden valley area, remains.