Combined annual report for the period ending 14 September 2010 EL 4170 Cato Plateau and EL 4171 Cato River, Cato Project

Abstract

EL 4170 Cato Plateau and EL 4171 Cato River were applied for by BHP Minerals Pty. Ltd. on 3rd October 1982. EL 4170 was granted on 14th October 2004, EL 4171 was granted on 12th September 2005. Rio Tinto Exploration Pty Limited (RTX, previously RTE) signed an agreement with BHP on 27th March 2000 whereby RTX took over management of the tenements. The original EL 4170 tenement application covered an area of 593.5 km2 of which only 57.0 km2 was granted. The remainder of the area was split off into a new application, EL 24389 and put into moratorium. The original EL 4171 tenement application covered an area of 846 km2 of which 598.2 km2 was granted. The tenements are located 30 km west of Nhulunbuy, east Arnhem Land and consequently are processed under the Aboriginal Land Rights Act 1975 (ALRA). Combined reporting of EL 417 and EL 4170 was granted on 3 August 2007, and called the 'Cato Project'. The Cato Project forms part of the larger contiguous tenement package in east Arnhem Land, which is prospective for bauxite. The Cato project area covers part of the Cato Plateau, which is a well-documented occurrence of bauxite within the east Arnhem area. The Cato Plateau target, has the potential to contain resources similar in style to the nearby Gove deposit. BHP Billiton, through an agreement with RTX, retains the right to explore for manganese (Mn) on EL4170 and EL4171. This combined annual report describes the exploration work completed by RTX and BHPB within Exploration License (EL) 4170 and EL4171 during the reporting period. Between 15 September 2009 and 14 September 2010, RTX completed the following work on EL4170 and EL4171: Analysis of 20 surface rock samples; Partial relinquishment of EL 4171. BHP Billiton completed the following work on EL4170 and EL4171: Re-processing of EM survey data on EL4171. No ground disturbing work was completed during the annual reporting period ending 14 September 2010.