Wiluna Uranium Project Process Development AusIMM Adelaide AusIMM - PowerPoint PPT Presentation

Wiluna Uranium Project Process Development AusIMM Adelaide AusIMM Adelaide 17 June 2010 17 June 2010 Dayle Kenny Eugene Dombrose Eugene Dombrose

Disclaimer This presentation has been prepared by Toro Energy Limited (“Toro”). The information contained in this presentation is a professional opinion only and is given in good faith. Certain information in this document has been derived from third parties and though Toro has no reason to believe that it is not accurate, reliable or complete, it has not been independently audited or verified by Toro. Any forward-looking statements included in this document involve subjective judgement and analysis and are subject to uncertainties, risks and contingencies, many of which are outside the control of, and maybe unknown to, Toro. In particular, they speak only as of the date of this document, they ti i f hi h t id th t l f d b k t T I ti l th k l f th d t f thi d t th assume the success of Toro’s strategies, and they are subject to significant regulatory, business, competitive and economic uncertainties and risks. Actual future events may vary materially from the forward looking statements and the assumptions on which the forward looking statements are based. Recipients of this document (“Recipients”) are cautioned to not place undue reliance on such forward-looking statements. Toro makes no representation or warranty as to the accuracy reliability or completeness of information in this document and does not take responsibility for Toro makes no representation or warranty as to the accuracy, reliability or completeness of information in this document and does not take responsibility for updating any information or correcting any error or omission which may become apparent after this document has been issued. To the extent permitted by law, Toro and its officers, employees, related bodies corporate and agents (“Agents”) disclaim all liability, direct, indirect or consequential (and whether or not arising out of the negligence, default or lack of care of Toro and/or any of its Agents) for any loss or damage suffered by a Recipient or other persons arising out of or in connection with any use or reliance on this presentation or information Recipient or other persons arising out of, or in connection with, any use or reliance on this presentation or information. All amounts in A$ unless stated otherwise. Competent Persons Statements: Competent Persons Statements: The information in this report that relates to Mineral Resources is based on information compiled by Mr Daniel Guibal who is a Fellow of the Australasian Institute of Mining and Metallurgy (AusIMM). Mr Guibal is a fulltime employee of SRK Consulting and has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity he is undertaking to qualify as a Competent Persons as defined in the 2004 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves’. Mr Guibal consents to the inclusion in this release of the matters based on his information in the form and context in which it appears. 2

Wiluna Uranium Project j • Location, Environment • Resource Resource • Project Resource Res rce • • Mining • Process Development Process Development • 3

Wiluna Uranium Project j 4 Location

Wiluna Uranium Project j Environment Land forms Delta System; calcrete flats, sand dunes, • samphire flats Lake bed, creek bed • Previous land use Heritage, Pastoral, Mining g , , g • 5

Wiluna Uranium Project j Resource Calcrete / clay hosted carnotite mineralisation • Within delta generally below the water table Within delta, generally below the water table • • Resource estimate using uniform conditioning • Lake Way is predominantly assay data • Centipede is all gamma data • Resource Grade Contained Contained Million Million U 3 O 8 U O U O U 3 O 8 Prospect Prospect Category Category U 3 O 8 Mlb Tonnes ppm Tonnes Centipede Measured 0.30 588 177 0.39 Centipede Indicated 7.68 619 4,754 10.48 Centipede Inferred 1.69 251 424 0.94 Total Centipede 9.68 553 5,355 11.81 Lake Way 10.53 543 5,714 12.60 Inferred Total Wiluna Project 20.21 548 11,070 24.40 6

Wiluna Uranium Project j Mining • Whittle optimisation of the Uniform Conditioned Resource • Selective mining with intensive grade control Selective mining with intensive grade control • Ore is below the water table 7

Wiluna Uranium Project j Process Development – Early T estwork Australian Nuclear Science and T echnology Organisation (ANSTO) in 2007. Observations included: Entrained chlorides readily removed by water washing Entrained chlorides readily removed by water washing • • Upgrading by scrubbing and screening not possible • Uranium extraction amenable to acid and alkaline leaching Uranium extraction amenable to acid and alkaline leaching • • High acid consumption (700 kg/t) • Tailings difficult to settle Tailings difficult to settle • • High recovery from low chloride pregnant liquor achieved • using RIP using RIP Column alkaline leach achieved 70% extraction in 17 weeks •

Wiluna Uranium Project j Process Development – Early T estwork T est Outcomes Head grade of sample about double average resource grade Head grade of sample about double average resource grade • • Test results deemed indicative only but adequate for PFS level • study of following options: study of following options: • Option A – CCD Chloride Wash, Agitated Leach and RIP • Option B – Dump Chloride Wash, Dump Leach, and IX • Option C – ROM Chloride Wash, Agitated Leach and RIP • Option D Agitated Leach and Direct Precipitation • Option D – Agitated Leach and Direct Precipitation Option D studied at conceptual level only and assumed direct precipitation Option D studied at conceptual level only and assumed direct precipitation of SDU

Wiluna Uranium Project j Process Development – 2008 Prelim Feasibility Study 2008 PFS - Summary of Results: Option A Option B Option C Option D CCD Dump ROM Direct Wash Leach Wash Precipitation RIP RIP IX IX RIP RIP Throughput Mt/a 1.5 2.0 1.5 1.5 Production t/a U 3 O 8 661 648 661 661 Recovery % 86.8 70.0 86.8 86.8 Capital Cost M$A 305.4 195.7 274.6 247 Operating Cost $A/t Ore O i C $A/ O 51.0 51 0 36 1 36.1 48 1 48.1 43 1 43.1 Operating Cost $A/lb U 3 O 8 52.5 50.6 49.5 44.0 Water Requirement GL/a q 3.4 1.5 2.3 2.9

Wiluna Uranium Project j Process Development – SDU T ests and 2008 Options Study T ests at Ammtec demonstrated effective precipitation of SDU from high Chloride low, Uranium solutions leading g , g to study of following options: Agitated Leach and direct precipitation of SDU • Heap Leach and direct precipitation of SDU Heap Leach and direct precipitation of SDU •

Wiluna Uranium Project j Process Development – 2009 Optimisation Study Supporting testwork on blended sample included: S Scrubbing and screening bbi d i • Comminution • Leaching Leaching • • • T emperatures 90 to 150 o C • Various Carbonate/Bicarbonate concentrations • Grind sizes up to all passing 1mm • Chloride levels up to 70 g/L SDU precipitation at chloride levels up to 70 g/L • Mineralogy •

Wiluna Uranium Project j Process Development – 2009 Optimisation Study Summary of Results Option D Option E Conventional Heap Leach Leach Throughput Mt/a 1.3 1.6 Production t/a U 3 O 8 615 616 Recovery % Recovery % 86.0 86 0 70.0 70 0 Capital Cost M$A 257.9 163.9 Operating Cost $A/t 48.41 35.09 Ore Ore Operating Cost 46.43 41.35 $A/lb U 3 O 8 W t Water Requirement R i t 1 7 1.7 0 7 0.7 GL/a

Wiluna Uranium Project j Process Development – 2009 Optimisation Study Heap Leach v Agitated Tank Leach – Other Considerations Advantages Advantages Lower operating and capital costs • Residues easier to handle Residues easier to handle • • Requires less water • Technically simpler circuit requiring less skilled operators Technically simpler circuit requiring less skilled operators • Disadvantages Slower leach kinetics and lower extraction • Little scope for controlling process once underway • Not widely used technology, especially with direct precipitation • Delayed revenue stream •

Wiluna Uranium Project j Process Development – 2009 Optimisation Study Conclusions and Recommendations Financial evaluation confirmed heap leach as preferred option • Retain conventional leach as alternate R i i l l h l • Commence comprehensive heap leach test program to • confirm study assumptions

Wiluna Uranium Project j Process Development – Heap Leach T est Program T est program: Agglomeration and percolation Agglomeration and percolation • • Bottle rolls • Small columns to establish conditions • Small columns to confirm conditions on main ore types Small columns to confirm conditions on main ore types • Medium scale columns to accommodate coarser ore • Large scale (6m) columns for pilot testing in closed circuit • Trial heap on site (4,500 tonnes) • (Tests in blue have been completed or underway)