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2013). The PFS included hydrogeological, geotechnical, mining, metallurgical and process engineering studies, as well as environmental impact assessments.
Further work The nature and scale of planned further work (eg tests for lateral extensions or depth extensions or large-scale step-out drilling). Further work planned for the Alameda deposit includes additional infill drilling focused on improving geological confidence and resource classification.Geological studies
will include detailed interpretation of lithology, structure and weathering and an assessment of potential relationships between these factors and uranium grade
distribution. Further work is also planned on a number of other exploration targets within the Alameda Region.
Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive. These have been included in previously reported ASX releases.
Further work planned for the Alameda deposit includes additional infill drilling focused on improving geological confidence
and resource classification.Geological studies will include detailed interpretation of lithology, structure and weathering
and an assessment of potential relationships between these factors and uranium grade distribution. Further work is also
planned on a number of other exploration targets within the Alameda Region.
Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future
drilling areas, provided this information is not commercially sensitive.
These have been included in previously reported ASX releases.
Section 3 Estimation and Reporting of Mineral Resources
(Criteria listed in the preceding section also apply to this section.)
Database integrity Measures taken to ensure that data has not been corrupted by, for example, transcription or keying errors, between its initial collection and its use for Mineral Resource estimation purposes. Drill hole data is stored in a password protected relational database (Access). Drill data recorded in digital Excel templates is transferred to the database by the
project geologist who is responsible for reviewing and validating the data. Assay data is received from the external laboratories in digital format and is loaded directly
into the database after QA/QC has been checked and validates the rest of assays.Geological logging is restricted to appropriate codes relevant to the local geology,
mineralisation, weathering and alteration setting. A copy of the master database is linked to Surpac mining software for Mineral Resource Estimation.
Data validation procedures used. Database validation checks including collar survey position, down hole survey control, assay limits, eU3O8 profiles, sample intervals and logging codes are completed
prior to the data being transferred to the master database.
Site visits Comment on any site visits undertaken by the Competent Person and the outcome of those visits. Sampling techniques and procedures, as well as QA/QC data, are reviewed internally an ongoing basis. Chris Arnold (Principal Geologist, AMC Consultants (UK)) reviewed the
sampling techniques, procedures, data and resource estimation methodology. He undertook a number of site visits to review and inspect the application of these procedures.
He concluded that the sampling and analytical results available were appropriate for estimation of the Mineral Resource.
If no site visits have been undertaken indicate why this is the case. Site visits have been undertaken.
Geological interpretation Confidence in (or conversely, the uncertainty of) the geological interpretation of the mineral deposit. The confidence of the geological interpretation is appropriate for the current level of resource estimation. The resource is defined within mineralised envelopes which
encompass all zones of significant mineralisation.
Nature of the data used and of any assumptions made. Geology and mineralisation interpretation is based on geological logging and sample assays derived from RC and DD drilling, along with cross sectional interpretations
which include surface mapping information and geophysical studies.
The effect, if any, of alternative interpretations on Mineral Resource estimation. Structural studies show dips of structures vary between 30° and vertical however; the uranium mineralisation has undergone supergene remobilisation and is interpreted to
be flat lying to shallowly dipping and generally within 180m from surface.
The use of geology in guiding and controlling Mineral Resource estimation. On the deposit scale the uranium grade is controlled by both lithology and structure, while on a local scale the grade is interpreted to be influenced by supergene
processes.
The factors affecting continuity both of grade and geology. Geological logging and uranium assay of samples from drill holes has demonstrated the continuity of the grade and lithology between mineralised sections. Breaks in
continuity are likely due to structural offsets, some of which have been observed or interpreted from surface mapping.
Dimensions The extent and variability of the Mineral Resource expressed as length (along strike or otherwise), plan width, and depth below surface to the upper and lower limits of the Mineral Resource. The Alameda uranium mineralisation covers an area of approximately 2km by 1.2km and generally occurs within 180m of surface.
Estimation and modelling techniques The nature and appropriateness of the estimation technique(s) applied and key assumptions, including treatment of extreme grade values, domaining, interpolation parameters and maximum distance of extrapolation from data points. If a computer assisted estimation method was chosen include a description of computer software and parameters used. A mineralised envelope is created encompassing all zones of significant mineralisation. A number of different domains have been interpreted.Geostatistical variogram
modelling was used to determine appropriate parameters for estimation of uranium. Primary estimation is a pass with Ordinary Kriging (OK) methodfor domains Z11 and Z13
and Inverse Distance Squared Weighting (ID2) for the remaining domains.Datamine software was used for mineralisation volume interpretation and uranium grade estimation by
AMC.Four sources of drillhole uranium grade data was used:· Berkeley Chemical U3O8 (ppm): 13%· Berkeley Radiometric Equivalent eU3O8 (ppm): 23%· Berkeley
Portable XRF U3O8 (ppm): 1%· ENUSA Chemical U3O8(ppm): 63%The drill hole spacing is nominally 50m by 50m, with some closer spacing at 35m by 35m.Five mineralisation
domains were identified at Alameda (Z9, Z11, Z12, Z13 and Z14). 2m samples composites were used to estimate grade into 10m by 10m by 6m parent blocks, allowing sub
-blocking of 5m by 5m by 3mIn order to reduce local bias due to extreme high grades, top cuts were applied: · Z9: 2,000ppm U3O8· Z11: 8,000ppm U3O8· Z12:
4,000ppm U3O8· Z13: 5,000ppm U3O8· Z14: 4,000ppm U3O8Search ellipse radii variable for all domains in metres, along-strike /across-strike/down-dip (1st and 2nd
pass):· Z9: 75/75/6 to 150/150/6· Z11-13: 40/40/6 to 80/80/6Search orientation variable per domain (dip, plunge, dip dir.): · Z9: 0/0/347· Z11:
0/0/347· Z12: 15/0/262· Z13: 30/0/267· Z14: 30/0/262Search radii used for OK was mostly 40/40/5 (major/semi-major/minor) to estimate a grade for blocks not
estimated in the 1st pass, the radii were doubled on the 2nd pass. In-situ dry bulk densities were assigned based on zones of weathering intensity and used to estimate
tonnage. Densities are from diamond core measurements using the Archimedes principle.
The availability of check estimates, previous estimates and/or mine production records and whether the Mineral Resource estimate takes appropriate account of such data. The reported resource estimate was compared with the previous resource estimate (September 2010) which was based on earlier drill campaigns and historical ENUSA resource
estimates. Both of which support the reported MRE. No mining production has taken place at Alameda.
The assumptions made regarding recovery of by-products. The resource model only estimates uranium.
Estimation of deleterious elements or other non-grade variables of economic significance (eg sulphur for acid mine drainage characterisation). At this stage, there are no deleterious elements or other non-grade variables identified as being of economic significance at Alameda.
In the case of block model interpolation, the block size in relation to the average sample spacing and the search employed. The uranium grade is estimated into the 10m (X) by 10m (Y) by 6m (Z) blocks. This compares to the average drill spacing of 35m by 35m in X and Y and an assumed mining
bench height of 6m. This block size was chosen to match the potential open cut mining methodology.
Any assumptions behind modelling of selective mining units. Two selective mining unit dimensions have been considered in the current model:· North covering an area of 1.5km by 0.5-0.02km within 50m of surface.· South
with an area of 0.8km by 0.2km within 150m of surface.Both areas contain mineralised zones that average between 20m to 50m in thickness.
Any assumptions about correlation between variables. Uranium is the only economic metals estimated in the current resource model.
Description of how the geological interpretation was used to control the resource estimates. Geological interpretation controlled the volume of the resource estimate by restricting the interpretation of the mineralisation volume and associated samples to material
with continuity above a 100ppm U3O8 grade.The domains are based on geology, structure and uranium grade with defined zones of mineralisation that show continuity along
and across strike.A further division of the model into completely weathered, partially weathered and fresh rock is applied by triangulated surfaces interpreted from the
logging of the drill samples. This division is only applied for density purposes.
Discussion of basis for using or not using grade cutting or capping. Uranium grade distribution exhibits a strong positive skewness, so a top cut was applied to reduce local bias by extreme grades outliers - nominally approximating the
97.5 population percentile. The domains were assessed independently and a top cut grade was determined for each domain.
The process of validation, the checking process used, the comparison of model data to drill hole data, and use of reconciliation data if available. Validation of the MRE included visual inspection of the grade distribution compared to the drill data, comparison of block model statistics to the sample statistics and
generation of swath plots. These confirmed that the MRE appropriately represents the grade and tonnage distribution of the uranium mineralisation at the confidence levels
reported.
Moisture Whether the tonnages are estimated on a dry basis or with natural moisture, and the method of determination of the moisture content. The resource tonnage is reported on a dry bulk density basis. In-situ dry bulk density measurements were completed on dry core (Archimedes method) and sample grades are
reported using dry weight.No moisture content of drill core has been determined.
Cut-off parameters The basis of the adopted cut-off grade(s) or quality parameters applied. The MRE has been reported using a 200ppm U3O8 cut-off grade. The Salamanca Project PFS demonstrated that a ~100ppm U3O8 cut-off is economic. Based on the current uranium
market, reporting of the MRE at a 200ppm cut-off grade is both justifiable and consistent with previous published MRE's for this style of mineralisation.
Mining factors or assumptions Assumptions made regarding possible mining methods, minimum mining dimensions and internal (or, if applicable, external) mining dilution. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential mining methods, but the assumptions made regarding mining methods and parameters when estimating Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the mining assumptions made. The PFS demonstrated that the Alameda resource can potentially be extracted using open pit mining methods, with the recovery of uranium through the application of acid
heap leach methods.Indicative parameters used for pit optimisation purposes were:Uranium selling price: US$65/lb U3O8, Total Mining Cost: US$9.76/lb U3O8Mining recovery:
97.5%Mining dilution: 5%Plant Process Cost: US$10.41/lb U3O8Recovery U3O8: 85%Royalties: 3.7%
Metallurgical factors or assumptions The basis for assumptions or predictions regarding metallurgical amenability. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential metallurgical methods, but the assumptions regarding metallurgical treatment processes and parameters made when reporting Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the metallurgical assumptions made. Berkeley has completed a number of metallurgical testwork programs for Alameda as part of the scoping, PFS and definitive feasibility studies, including column leach
tests at commercial height (6m). These tests have shown that heap leaching can achieve uranium recoveries of at least 85%.
Environmen-tal factors or assumptions Assumptions made regarding possible waste and process residue disposal options. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider the potential environmental impacts of the mining and processing operation. While at this stage the determination of potential environmental impacts, particularly for a greenfields project, may not always be well advanced, the status of early consideration of these potential environmental impacts should be reported. Where these aspects have not been considered this should be reported with an explanation of the environmental assumptions made. Spent ore from the on-off heap leach pads ('ripios') will initially be stored on the heap leach pads and subsequently backfilled into isolated and lined (clay layer and
HDPE liner) areas within the mined pits on a continuous basis once sufficient space is available.Acid Rock Drainage (ARD) and Natural Occurring Radioactive Materials
(NORM) waste will be placed onto temporary dumps designed with the required isolation system (clay layer and HDPE liner) until the waste is backfilled into the mined pits
towards the end of the mine life. At the end of the mine life, the entire volume of ripios, ARD and NORM waste will be fully encapsulated within the mined pits, and the
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