Practice of 2:1 waste rock dump reclamation slope at Batu Hijau – a 20 year journey creating the best legacy

The Batu Hijau’s orebody is a world-class copper-gold porphyry owned by PT Amman Mineral Nusa Tenggara located in previously uninhabited forestland with sloping terrain southwest of Sumbawa Island. climatic condition influenced two distinct monsoon periods, namely the east which characterized low rainfall and humidity level extends from May through September, west monsoon, November March each year. Annual precipitation 2,511 mm over 75 percent occurring during monsoon. The construction phase started 1997 it took 3 years before production 2000. Reclamation performed concurrently integrated into annual mine plan update. Numerous studies had been since early stages exploration that including tree species selection, PROSPER forest vegetation/ soil hydrology model to determine thickness, water holding capacity, 2:1 new test slope (NEWTS). This paper outlines development 2: 1 reclamation waste dump has carried out 20 land preparation, erosion control techniques, transplanting, monitoring, evaluation. This achievement assures Hijau program’s goal restore ex-mining area similar its pre-mining achievable.