MLN 1121 Annual Report 5 January 2013 to 4 January 2014

Abstract

The McArthur River mine is one of the world's largest zinc, lead and silver mines, situated approximately 70 kilometres southwest of Borroloola, near the Gulf of Carpentaria in the Northern Territory. It is operated by McArthur River Mining (MRM), a subsidiary of the Swiss mining company Glencore Xstrata. Although discovered in the 1950s, when it was originally named the HYC ('Here's Your Chance') deposit, mining operations did not commence until 1995. MLN 1121 encompasses the main pit area of the McArthur River Mine and was granted in 1993. Initially an underground mining operation, the mine transitioned across to an open-cut operation in 2006. The sediment hosted stratiform HYC deposit is approximately 1.5km long and 1.0km wide with an average thickness of 55m. The HYC deposit has similarities with ore-bodies at Mount Isa in Queensland. Analytical results from the 2012 Waste Characterisation Drilling Program became available during the reporting period and were appended to the site geological database. In total, analysis results from 339 waste characteriation samples and 230 orebody samples were returned to MRM. Hangingwall waste domains were rebuilt, estimation parameters for hangingwall domains were regenerated and metal values were estimated through a new hangingwall model. No field based exploration activities on MLN 1121 were undertaken during the reporting period.