kann jeder froh sein wenn er draußen ist
Panguna erosion could devastate
By Leonard Fong Roka
Clean section of the Kavarong River waterway.
When the Bougainville Copper Limited (BCL) began its mine in Panguna in the 1960s it created an open-pit mine that is about two kilometres wide and half a kilometer deep. Before this could be achieved it required the clearance of jungle which occupied the space and million tonnes of overburden was washed down the present day Tumpusiong Valley.
The company’s operation greatly affected the natural environmental activity of the area’s main river system, the Kavarong.
The progress of mining at Panguna led to a build-up of waste gravel and rock dumps, the Kavarong River left its original banks and soared into heights of where the jungle used to be.
The waste rocks that filled in the Kavarong valley buried villages such as Dokotonama, Unang and Dapera and required the re-settlement of others.
The course of the Kavarong River was altered to safeguard the mining operation and sits on an artificial river bed that is now severely affected by weather.
This artificial part of Kavarong runs on a BCL made V-shaped concrete bed network starting from the fringes of the former Panguna Township to the north-east and meanders beside the few protruding slopes of the western perimeters right to where the gravel dumps were halted in 1989. This is a distance of estimated 4 kilometres.
Before the conflict BCL maintained the concrete river bed but now it is unattended. Years of erosion washed away the gravel that supports the river bed in some sections creating space beneath the concrete bed.
In other sections landslides filled into the concrete bed resulting in the blocking of the river into a massive pool where water is now being leaching into the gravel dumps which also contribute to sinkholes along the waterway.
Local gold miners had also contributed by digging gravel that supports the water way, which allowed rain to accelerate the formation of sinkholes.
All these actions had weakened the massive concrete in few areas.
Today the Kavarong – the sections within the mining site – are a potential threat to the Tumpusiong Valley villages, the people below and the major Arawa to Nagovis/Siwai/Buin highway that runs through the mine and the Tumpusiong Valley.
The breakdown of the V-shape river bed will be soon a disaster.
Its bursting will wash away the millions and millions of tonnes of stored gravel and rock dumps into the Tumpusiong Valley.
The first village to be buried will be Pirurari that stands on the foothills of these dump mountains. Then it will back-feed the Kavarong in the Tumpusiong scaring away people that had settled on the banks due to the ceasing of the Panguna mine costing them more for their finance, the gold in the present Kavarong river bed, will be buried.
Pirurari village is precariously below the eroding waterway.
The highway from South Bougainville will be cut off affecting businesses and services for most people and also bring new impacts to the sedimentation in the Banoni coastline of South Bougainville.
Since the Bougainville government has not so long financially catered for this imminent disaster catalyst every time the highway has being kept with funding for upgrade, it is now obvious the Panguna landowners and the BCL have to decide the prevention of a disaster on a Bougainville people from this mine-related hazard.
Environment, Infrastructure, Issues Admin 27th October 2013
