REG - Berkeley Energia - DFS confirms Salamanca as a low cost producer <Origin Href="QuoteRef">BKY.AX</Origin> - Part 12
14/07/2016 08:20
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a global scale. It relies on historical data being of similar standard as recent infill drilling. The relevant tonnages and
grade are variable on a local scale and have been simulated using UC and LUC for SMU dimensions of 5m by 5m by 6m.The CP
considers that the drilling grid in the area that was the focus of the 2014 infill drilling campaign is sufficient for
classification of a Measured Mineral Resource.
The statement should specify whether it relates to global or local estimates, and, if local, state the relevant tonnages, which should be relevant to technical and economic evaluation. Documentation should include assumptions made and the procedures used. The Retortillo deposits are likely to have local variability. The global assessment is an indication of the average tonnages and
grade estimate for each geological domain.
These statements of relative accuracy and confidence of the estimate should be compared with production data, where available. No production has been carried out at Retortillo.
No production has been carried out at Retortillo.
Section 4 Estimation and Reporting of Ore Reserves
(Criteria listed in section 1, and where relevant in sections 2 and 3, also apply to this section.)
Mineral Resource estimate for conversion to Ore Reserves Description of the Mineral Resource estimate used as a basis for the conversion to an Ore Reserve. A mineral resource has been estimated using block modelling techniques as describes in Section 3 of Table 1. A block model of
5x5x6 m has been created and the resource estimated using Ordinary Krigging and Uniform Conditioning. Retortillo Mineral
Resource at 110 ppm mining cut off Santidad Mineral Resource at 100 ppm mining cut off
Clear statement as to whether the Mineral Resources are reported additional to, or inclusive of, the Ore Reserves. The mineral resource estimate is inclusive of any ore reserves
Site visits Comment on any site visits undertaken by the Competent Person and the outcome of those visits. Site visits took place from 9th to 12th of November 2015. The following inspections were made:· The site of the pit·
The site of the proposed dump sites· The site of the proposed plant site including the ore stockpile· The core yard
where cores were inspected· The access to the site and existing infrastructure around the site.No material issues that are
likely to prevent the establishment of mining and processing activities at the site were identified during the site visit.
If no site visits have been undertaken indicate why this is the case. Site visits have been undertaken.
Study Status The type and level of study undertaken to enable Mineral Resources to be converted to Ore Reserves. The level of study is Definitive Feasibility Study. Only measured and indicated resources have been considered in the
declaration of ore reserves
The Code requires that a study to at least Pre-Feasibility Study level has been undertaken to convert Mineral Resources to Ore Reserves. Such studies will have been carried out and will have determined a mine plan that is technically achievable and economically viable, and that material Modifying Factors have been considered. All factors required to convert Resources to Reserves have been considered including capital and operating costs, selling
prices, geotechnical conditions, metallurgical recoveries and reagent consumptions, environmental and social constrains, etc.
These factors were used to determine the optimum economic pit shell (using Whittle optimization software). The optimal pit shell
was used as the basis to design an open pit that considers slope angles, ramps and berms in the different sectors of the pit.
The reserves reported are within the final pit design. The use of these factors has resulted in a technically and economically
viable plan.
Cut-off parameters The basis of the cut-off grade(s) or quality parameters applied Cut-off grade has been estimated using a combination of factors:· Different selling price: from 45$/lb to 65$/lb· Mine
costs derived from the analysis of 5 different proposals from mining contractors.· Recoveries and acid consumption obtained
from metallurgical testwork done at Mintek (South Africa) for 6 m columns.· Rehabilitation costs. The cut-off grade applied
is 110ppm for the Retortillo deposit and 100ppm for the Santidad deposit.
Mining factors or assumptions The method and assumptions used as reported in the Pre-Feasibility or Feasibility Study to convert Mineral Resource to an Ore Reserve (i.e. either by application of appropriate factors by optimisation or by preliminary or detailed design). A mine design to definitive feasibility study levels of accuracy has been undertaken as the basis for the estimation of Ore
Reserves. This study has included:· Exploration and sampling of the deposit· Modelling and estimation of mineral
resources· Mine design of an open pit including a pit optimization study· Design of all dumps and stockpiles
required.· Metallurgical testwork· Metallurgical process and plant design· Determination and design of all
infrastructure requirements· Costing based on multiple quotes· Financial evaluation by discounted cashflow analysis
The choice, nature and appropriateness of the selected mining method(s) and other mining parameters including associated design issues such as pre-strip, access, etc. The deposit is shallow (between 0 to 140m) and massive, the pre-strip is therefore low with a stripping ratio 2.2 (t to t). Due
to the depth and geometry of the deposit, the selected mining method is Open Pit mining ensuring a good recovery of the deposit.
Some of the pre-strip material will be used as construction material. Access to the pit will be by conventional open pit ramps,
25m in width that enables access for 100 t trucks.
The assumptions made regarding geotechnical parameters (eg pit slopes, stope sizes, etc), grade control and pre-production drilling. Geotechnical design parameters have been derived for the various material types encountered at the site based on core logging
and laboratory test work. Open pit slopes have been divided into different design sectors and each of them has specific
conditions applied. Overall slope angles in the identified design sectors range from 34 degrees to 53 degrees. Grade control
will be done based on two main sources of data:· Portable XRF on blast hole collected dust and rock chips· Blast hole
chemical assay Routine XRF testing will provide the basic information for ore grade control in the ore. The cost for these
activities has been considered as part of the labour cost of the Berkeley technical services. The blast hole samples will be
collected as 6 m composites. Face mapping and geological logging are used to confirm the results. It has been assumed that 30%
of the total ore samples and 10% of the waste samples will be sent to the laboratory for the first year as part of a QA / QC
process for the gamma probing. After first year, only 10% of ore blast holes and 5% of waste blast holes will be collected for
chemical analysis.
The major assumptions made and Mineral Resource model used for pit and stope optimisation (if appropriate). A Pit optimisation study was undertaken the techno-economic data set used in this optimisation process were largely based on the
outcomes of the pre-feasibility study with the exception of the geotechnical parameters which were determine to DFS levels of
accuracy.
The mining dilution factors used. Planned dilution of Retortillo and Santidad was applied through regularisation of the block model. The original resource model
produced by CSA was populated with minimum block sizes of 5x5x1.5. The block model was then regularised to 5x5x6 to account for
the selective mining unit. In addition to this, dilution of 4% and mining recovery of 95% was applied to account for unplanned
dilution due to blast movement, mixing of ore and waste and mining angles.
The mining recovery factors used. Mining recovery factor used is 95%
Any minimum mining widths used. SMU is 5x5x6m, minimum width for mining is established as 30m
The manner in which Inferred Mineral Resources are utilised in mining studies and the sensitivity of the outcome to their inclusion. No Inferred material is used in the study, all reserves estimated are based on measured and indicated resources.
The infrastructure requirements of the selected mining methods. The infrastructure required is minimum: access by road, power and water. The mining infrastructure cluster will be provided by
the selected mining contractor. A metallurgical process plant will be constructed.
Metallurgical factors or assumptions The metallurgical process proposed and the appropriateness of that process to the style of mineralisation. The heap leach process is proposed followed by SX and ADU precipitation. The ADU precipitate (yellowcake) is calcined to produce
U3O8. The high recoveries obtained from testwork (87% including a scale-up factor of 2%) and the low acid consumption makes heap
leaching the preferred process route. Ore, when crushed, breaks along the fractures where the uranium minerals occur, hence
milling or fine crushing is not required. The 40mm liberation size is achieved with only primary and secondary crushing. Acid
leaching has been demonstrated to be the preferred process. Tank leaching, although increasing recovery by 2-3%, has
significantly higher capital and operational costs, and so is economically a less attractive process than heap leaching.
Whether the metallurgical process is well-tested technology or novel in nature. The process method selected is the standard method for mineralogically similar uranium ores. A number of mines world-wide
operate utilising heap leaching with sulphuric acid. The plant recoveries achieved are typically similar to the results
predicted by the testwork.
The nature, amount and representativeness of metallurgical test work undertaken, the nature of the metallurgical domaining applied and the corresponding metallurgical recovery factors applied. Testwork was carried out using 1-metre and 6-metre high columns. Samples used were composites from each of the mining areas
(north-west, central and south-east). The samples used are considered to be representative of these mining areas. Overall
uranium recoveries reported are weighted averages of the dissolutions achieved in 6m column testwork, multiplied by the
proportion of ore represented by the sample, multiplied by a scale-up factor of 98%. This factor is reasonable.
Any assumptions or allowances made for deleterious elements. At this stage, no deleterious elements have been identified as being of economic significance.
The existence of any bulk sample or pilot scale test work and the degree to which such samples are considered representative of the orebody as a whole. The samples for 6 metre column tests were composites of each mining area. The samples used are considered to be representative
of the respective mining areas. The 6m column tests are accepted as being pilot scale tests.
For minerals that are defined by a specification, has the ore reserve estimation been based on the appropriate mineralogy to meet the specifications? The major uranium minerals in the orebody are uraninite and coffinite, accounting for more than 97% of the uranium content. The
product mineralogy does not depend on the minerals in the ore, due to after the leaching process, all soluble uranium is
precipitated as U3O8
Environmental The status of studies of potential environmental impacts of the mining and processing operation. Details of waste rock characterisation and the consideration of potential sites, status of design options considered and, where applicable, the status of approvals for process residue storage and waste dumps should be reported. Environmental Impact Assessments completed and approved by authoritiesWaste rock characterization has been completed. Studies
have been performed with Golder Associates Ibérica and AGQ laboratories. Characterization studies are based on Spanish and
European Union legislation, summarized in two main decrees:· Real Decreto 975/2009· Real Decreto 777/2012 Those two
decrees urge to perform testwork to define 50 samples distributed along orebody divided in 15 possible wastes and 4 possible ore
based on lithology and weathering has been tested.Waste has been divided into:· Inert: comprising Tertiary cover, and
Completely Weathered lithologies with less than 40ppm of U3O8.· Non-Inert: all the lithologies with more than 40ppm U3O8
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