A dry stock tailings facility is proposed to be designed in the King-King copper-gold project as an environment-friendlier state-of-the-art technology designed to withstand heavy rainfall.

The tailings facility will be under a R12-billion Environment Protection and Enhancement Program (EPEP) of the King-King joint venture (JV) partnership. King-King will require a $2-billion investment.

St. Augustine Gold and Copper Ltd (SAGC), JV partner in King-King, believes this dry stock tailings facility will do well to guarantee safety for the environment.

"In a tailings disaster, the tailings flow because it's wet. But this is dry. Even if there's an earthquake, there may be deformation, but the mound will not slide down. It will be stable," said Clyde Gillespie, SAGC country manager, in a press briefing.

"In a dry tailings facility, you don't have an embankment. The facility can store 850 million tons of tailings. You stack it higher and higher. There's a lot more capacity in smaller area. Capacity is for 22 years," he said.

The dry tailings technology has been developed in the United States and adopted in a South American mine.

"They stacked tailings for 15 years. They're one of the first to use the technology. But the rainfall there is much greater than any rainfall we'll see in King-King. That gives us confidence we'll be able to operate dry stack at King-King," said Gillespie.

Actual footprint in a dry stack tailings is much smaller than that in conventional tailings dam. Conventional ones require a bigger area because it has not only the solid tailings but water, occupying a stretched flat land.

"Being able to manage water runoff is very important. Water shouldn't carry a lot of soil. We want to improve water quality in the King-King River," he said.

Around the solid stack, there is a water diversion channel that catches rainwater that will in turn go to a treatment facility. At the end of the mine life, the dry stack will become vegetated and can become part of the natural environment. It may be useful as a golf course, a residential area, or a crop plantation.

Aside from the tailings management, other components of the EPEP are reforestation, construction of water treatment facility, air and water quality monitoring.

The JV plans to start mine construction in 2015. Its schedule is to produce copper cathode in 2017. It will produce gold and copper concentrate in 2018. The JV already started a 2,000 square meter nursery for its reforestation. This has seedlings for Robusta coffee, rambutan, durian, and mangosteen.

It will have a separate budget for mine closure and reforestation in mined out area.

The JV has so far provided a drinking water facility for 22 families and a chapel for the Gaka tribe in Brgy. Bongbong, Pantukan.

The company has done studies on the maximum credible earthquake in the area based on which the tailings facility is being designed. Other factors on the tailings facility design are earthquake possibility based on depth of the event and how far the earthquake event is from the area.

"It's based on an earthquake much greater than intensity 7.2," said Gillespie.(MMA)

SOURCE:MANILA BULLETIN | YAHOO NEWS PH