• Continued simplification of the Laguna Salada process flow sheet:
  • The life-of-mine operating cost, including royalties due to the State, were estimated at US$22 per pound of uranium, net of vanadium, in the PEA. Approximately 40% of this cost estimate is related to the management of sulphate (gypsum) that is present in the gravel, that competes with uranium and vanadium for the reagents used to leach the metals. So, finding a more cost-effective way of dealing with the sulphate is a priority in driving down production cost estimates. Alternative ways of controlling sulphate levels were examined and these results will be reported shortly;
     
  • The PEA modelled the processing of uranium and vanadium that was concentrated in very fine-grained (<0.075 millimetre ("mm")) powder that proved to be relatively costly to process since excess water had to be squeezed from it in filter presses that are not only expensive, but are costly to operate. The PEA design included six filter presses at a cost of US$2.1 million per unit. The current work tested a much coarser (0.85mm grain size) uranium-vanadium - bearing component of the gravel from which excess water should drain much more readily, thereby likely reducing the number of filter presses required. Results of this work are also expected shortly;
     
  • Test work is now planned for the uranium/vanadium separation and refining processes where there is further potential to reduce capex and opex. More efficient and proven processes and equipment successfully employed elsewhere on similar types of uranium/vanadium mineralized bodies will be tested and the expectation is that they will prove every bit as efficient with the Laguna Salada material; and
     
• Initial metallurgical test work is being done on unconsolidated sand and gravel samples from the relatively high-grade channels discovered beneath the layer of gravel on which the PEA was based. This will provide the first data as to how efficiently uranium and vanadium can be extracted from the channel fill. Results are expected in early January.

• Refining of the scrubbing process has reduced the residence time in the scrubbers from 15 minutes to only 5 minutes which will make the equipment smaller, cheaper and easier to operate as well as making the units more mobile;
   
• Changing the cut-point after scrubbing to a 0.85mm screen separates the coarse, pebbly component of the gravel that constitutes 77% of its mass, from the <0.85mm material that represents 23% of the gravel's mass. Although using the <0.85mm material involves processing almost three times the volume of material contemplated in the PEA, the size of the downstream equipment would increase only marginally because of the shorter residence time in each component of the equipment. Subsequent filtration and dewatering processes are likely to be simpler and should result in an overall cost reduction and improved process efficiencies (filtration results will be reported on shortly);
   
• The <0.85mm material contains 89% of the original gravel's uranium compared with 85% in the <0.075mm material modelled in the PEA. Alkaline leach extracted 94% of the contained uranium versus a marginally better 95% in the test work incorporated in the PEA. Overall, 84.5% of the gravel's uranium was extracted from the 0.85mm material, compared with 82.5% in the PEA - an increase of 2%.
   
• 46% of the gravel's vanadium was concentrated into the <0.85mm component against 29% in the 0.075mm component used in the PEA model. Alkaline leach at ANSTO extracted 55% of the vanadium, lower than the 71% extraction used in the PEA. However, processing of the coarser 0.85mm material still led to a better vanadium recovery: 25% of the gravel's vanadium was recovered from the 0.85mm material against 21% for the 0.075mm material used in the PEA - an increase of 23%;

3. Alkaline Leach

• Laguna Salada Deposit, Argentina - a PEA shows that this near surface, free-digging uranium-vanadium deposit has low production-cost potential; and
• Berlin Deposit, Colombia - a PEA shows that Berlin also has low-cost uranium production potential due to revenue that would be generated from by-products of phosphate, vanadium, nickel, rare earths (yttrium and neodymium) and other metals that occur within the deposit.