The Prospector News

Orezone Announces Positive Feasibility Study for Bombore

You have opened a direct link to the current edition PDF

Open PDF Close
Uncategorized

Share this news article

Orezone Announces Positive Feasibility Study for Bombore

 

 

 

 

 

Orezone Gold Corporation (TSX:ORE) is pleased to announce the highlights of the independent Feasibility Study for its wholly owned Bombore Gold Project in Burkina Faso, West Africa. The study envisions a shallow open pit mining operation with a processing circuit that combines heap leaching and carbon-in-leach without any grinding to process the soft and mostly free digging oxidized ores. The eleven-year mine plan, based on a mineral reserve using an US$1,100 gold price, is designed to deliver higher grade ore in the early years (0.88 g/t over the first eight years of production at a strip ratio of 1:1). Lower grade stockpiles will be processed in the final three years. The financial model with revenues based on a US$1,250 gold price, yields a robust 24.4% after tax internal rate of return to the Company (based on 90% ownership, 10% Gov’t) with a net present value of US$196 M at a 5% discount rate. Project payback is estimated at 2.7 years with all in sustaining costs averaging $678/oz. Initial capital is estimated at $250.0 M including contingencies, all working capital and a $10.5 M credit for gold revenues generated during the pre-production period. Capital costs include the mining fleet, a much larger water storage reservoir and higher resettlement costs than envisioned in the March 2014 Preliminary Economic Assessment. Sustaining capital is estimated at $75.2 M, taking into account the additional three years of mine life and higher resettlement costs than estimated in the PEA. Total reclamation and closure costs are estimated at $22.5 M including $8.7 M of heap rinsing costs expensed in year 12.
 

“The results of the Study are compelling and the project benefits from size, location, low reagent consumption, rapid leaching kinetics and low all-in operating costs,” said Ron Little, CEO of Orezone. “Bombore is one of the largest and most advanced undeveloped gold deposits in the region that lends itself to phased development. The initial 11 year phase requires less capital and has lower operating costs to process the shallow and softer oxidized ores. A second phase, at slightly higher gold prices (greater than US$1,400) could expand the standard CIL circuit with the addition of grinding to process the well-defined sulphide resource (73 Mt at 1.1 g/t for 2.6 Moz).”
 

The Study was completed by Kappes, Cassiday and Associates of Reno, Golder Associates, Inc. of Reno and Montreal, RPA Inc. of Toronto and WSP Canada Inc. of Montreal in conjunction with Socrege and BEGE of Burkina Faso.
 

Summary of Financials
 

The Base Case assumptions include mineral reserves using an average gold price of $1,100/oz and revenues based on $1,250/oz along with current prices for fuel, reagents and labor. Capital is based on quotes received from potential equipment and service providers between Q3 2014 to present. The financial highlights are as follows:
 

Base Case Highlights

 

 
 
----------------------------------------------------------------------------
                                                                            
----------------------------------------------------------------------------
  Mine Plan Contained Gold at $1,100 Au (ounces)                   1,465,000
----------------------------------------------------------------------------
  Average Gold Grade (g/t)                            LOM 0.76 / Years (1-8)
                                                                        0.88
----------------------------------------------------------------------------
  Processing Throughput (Mt/yr)                                          5.5
----------------------------------------------------------------------------
  Mine Life (years)                                                     10.7
----------------------------------------------------------------------------
  Average Annual Gold Production (ounces)          LOM 116,000 / Years (1-8)
                                                                     135,000
----------------------------------------------------------------------------
  Gold Production (ounces recovered)                               1,275,000
----------------------------------------------------------------------------
  Waste to Ore Strip Ratio (incl. pre-strip, water                          
   OCR)                                                            1.07: 1.0
----------------------------------------------------------------------------
  Gross Revenue ($M) using $1,250 Au                                   1,589
----------------------------------------------------------------------------
  Direct Cash Cost ($/oz)                                                554
----------------------------------------------------------------------------
  Operating Cost ($/oz)                                                  603
----------------------------------------------------------------------------
  Initial Capital ($M) (incl. $10.5M capital                                
   credit)                                                             250.0
----------------------------------------------------------------------------
  Sustaining Capital ($M)                                               75.2
----------------------------------------------------------------------------
  Closure Costs ($M) (incl. $8.7M of expensed                               
   costs)                                                               22.5
----------------------------------------------------------------------------
Attributable to Orezone (1)                                                 
----------------------------------------------------------------------------
  NPV after tax (0%) ($M)                                              323.9
----------------------------------------------------------------------------
  NPV after tax (5%) ($M)                                              196.1
----------------------------------------------------------------------------
  IRR after tax                                                        24.4%
----------------------------------------------------------------------------
Attributed to Government (2)                                                
----------------------------------------------------------------------------
  NPV (0%) with taxes ($M)                                             214.8
----------------------------------------------------------------------------
  NPV (5%) with taxes ($M)                                             152.7
----------------------------------------------------------------------------
(1) Represents Orezone's Burkina Faso subsidiary cash flows net of royalties
 and local taxes.                                                           
(2) The Government of Burkina Faso benefits from its 10% free-carried       
 interest, royalties (4% NSR), corporate tax (18.3%) and withholding taxes. 
Exchange Rates: USD : XOF = 550; Euro : USD = $1.19; Euro : XOF = 655.957   
Fuel price delivered to site (USD/L): Diesel $1.20, HFO $0.77               
----------------------------------------------------------------------------
 

 

 

The Mineral Resource and Mineral Reserve
 

The Mineral Reserve estimate prepared by RPA, is based on the 2013 Mineral Resource estimate prepared by SRK Consulting (Canada) Inc., which includes 139.9 Mt of M&I resources grading 1.01 g/t for 4.6 Moz plus 18.4 Mt Inferred resources grading 1.22 g/t for 0.7 Moz. The Study mineable reserve is limited to only the measured and indicated near-surface saprolite (oxide) and transitional (semi-oxidized) resources to an average depth of 45 m.
 

The Mineral Resource estimate consists of three separate block models:

 

 
 
--  The North model, which consists of the KT, Maga, CFU, OCR, and P8P9
    zones. 
--  The South model, which consists of the P11, Siga E, and Siga W zones. 
--  The Southeast model, which is to the south and southeast of the South
    model and consists of the P16 and P17 zones.
 

 

 

Mineral Resource Estimate – SRK Consulting (Canada) Inc., April 26, 2013

 

 
 
----------------------------------------------------------------------------
                       Measured Mineral  Indicated Mineral Inferred Mineral 
                           Resource          Resource          Resource     
                 Cut-              Cont-             Cont-             Cont-
                  off   Ton-       ained  Ton-       ained  Ton-       ained
                 Gold   nage Grade  Gold  nage Grade  Gold  nage Grade  Gold
Category          g/t     Mt   g/t   koz    Mt   g/t   koz    Mt   g/t   koz
----------------------------------------------------------------------------
North:                                                                      
Laterite/Oxide   0.45  13.57  0.95   417 14.20  0.82   375  2.04  0.88    57
Transitional     0.45   9.22  0.93   275  5.84  0.92   173  0.79  1.00    25
Fresh            0.50  22.04  1.00   711 11.98  1.29   497  4.42  1.63   232
Sub-total              44.83  0.97 1,402 32.02  1.02 1,046  7.25  1.35   315
----------------------------------------------------------------------------
South:                                                                      
Laterite/Oxide   0.45   8.11  0.94   246  4.53  0.86   125  1.66  0.89    48
Transitional     0.45   7.49  0.89   214  2.97  0.96    92  1.35  0.96    41
Fresh            0.50  20.58  1.02   674 15.26  1.19   584  5.46  1.26   222
Sub-total              36.17  0.98 1,134 22.76  1.10   801  8.46  1.14   311
----------------------------------------------------------------------------
Southeast:                                                                  
Laterite/Oxide   0.45   0.24  1.33    10  0.37  1.05    12  0.30  0.97     9
Transitional     0.45   0.25  1.53    12  0.34  0.97    11  0.24  0.97     7
Fresh            0.50   1.53  1.44    71  1.32  1.43    61  2.18  1.15    81
Sub-total               2.03  1.44    94  2.02  1.28    83  2.71  1.12    97
----------------------------------------------------------------------------
Combined:                                                                   
Laterite/Oxide   0.45  21.92  0.95   673 19.10  0.84   513  4.00  0.89   115
Transitional     0.45  16.96  0.92   501  9.14  0.94   275  2.37  0.97    74
Lat/Ox/Tr Total  0.45  38.88  0.94 1,174 28.24  0.87   789  6.37  0.92   189
Fresh            0.50  44.14  1.03 1,456 28.55  1.24 1,142 12.05  1.38   534
Total All                                                                   
Material               83.03  0.99 2,630 56.79  1.06 1,930 18.42  1.22   723
----------------------------------------------------------------------------
Total M+I All                                                               
Material              139.82  1.01 4,560                                    
----------------------------------------                                    
Total M+I                                                                   
Oxidized               67.12  0.91 1,963                                    
----------------------------------------------------------------------------
(i) Mineral resources are not mineral reserves and do not have a            
 demonstrated economic viability. All figures have been rounded to reflect  
 the relative accuracy of the estimates. The gold price of US$1,400 and the 
 cut-off grades from the previous resource estimation (2012) have been      
 retained for comparison purposes. Reported within conceptual open pit      
 shells optimized considering a carbon in leach CIL process option.         
----------------------------------------------------------------------------
 

 

 

For the Mineral Reserve estimate, RPA developed reserve block models, for each of the three resource block models, by applying modifying factors for conversion of Mineral Resources to Mineral Reserves. Those factors included amongst others, weathering profiles, operating costs, metallurgical recoveries, mining dilution & extraction and pit slopes.
 

Mineral Reserve Estimate – RPA, March 20, 2015

 

 
 
----------------------------------------------------------------------------
                       Proven             Probable        Proven & Probable 
                 Tonnes Grade Ounces Tonnes Grade Ounces Tonnes Grade Ounces
Category             Mt   g/t    koz     Mt   g/t    koz     Mt   g/t    koz
----------------------------------------------------------------------------
North             25.32  0.77    627  15.11  0.69    333  40.43  0.74    960
South             12.96  0.81    339   6.15  0.92    173  19.13  0.80    491
Southeast          0.18  1.17      7   0.18  1.18      7   0.36  1.18     14
----------------------------------------------------------------------------
Total             38.48  0.79    973  21.44  0.71    493  59.92  0.76  1,465
----------------------------------------------------------------------------
CIM definitions were followed for Mineral Reserves. Mineral Reserves are    
 estimated using a variable gold cut-off grade based on ore type and        
 location; estimated cut-off grades range from 0.30 g/t to 0.45 g/t gold.   
 Mineral Reserves are estimated using an average long-term gold price of    
 US$1,100 per ounce. A minimum mining width of five metres was used. Bulk   
 density is estimated in the Mineral Resource model by block; the average   
 density of ore is 1.8 t/m3. Numbers may not add due to rounding. Mineral   
 Reserves are included in the mineral resource.                             
----------------------------------------------------------------------------
 

 

 

Estimated Annual Gold Production
 

The Study assumes during years 1 through 8 an average annual mining rate of 13.9 Mt, including 5.5 Mt of ore. The ore is composed almost equally of +/- 212 micron material and is processed via the heap leach pad (+212 micron) and CIL (-212 micron) circuits. Average gold produced and average diluted grades for each year are summarized in the table below. Some gold is recovered during the pre-production period as a result of mining and processing the ore contained within the water storage facility (OCR). During years 9 to 11 ore is only processed from the lower grade stockpiles.

 

 
 
----------------------------------------------------------------------------
Year         -1    1    2    3    4    5    6    7    8    9   10   11 Total
----------------------------------------------------------------------------
Gold (Koz) 11.1  186  168  146  135  135  112  115   89   65   65   48 1,275
----------------------------------------------------------------------------
Grade                                                                       
 (g/t)     0.45 1.21 1.09 0.95 0.88 0.87 0.73 0.75 0.58 0.42 0.42 0.42  0.76
----------------------------------------------------------------------------
 

 

 

Summary of Operating Costs (excluding pre-production period)

 

 
 
----------------------------------------------------------------------------
                               Total Costs     Average Cost     Average Cost
Category                                $M    $/t processed             $/oz
----------------------------------------------------------------------------
Mining                                 299             5.06              234
----------------------------------------------------------------------------
Processing                             293             4.97              230
----------------------------------------------------------------------------
General Services                       111             1.88               87
----------------------------------------------------------------------------
Transport & Refining                   3.2             0.05              2.5
----------------------------------------------------------------------------
Cash Cost                              706            11.96              554
----------------------------------------------------------------------------
Royalties                               63             1.07               50
----------------------------------------------------------------------------
Total Cash Cost                      770 M            13.03              603
----------------------------------------------------------------------------
 

 

 

Initial Project Capital Cost Estimates
 

Initial capital costs are based on quotes of equipment and services from potential providers.

 

 
 
----------------------------------------------------------------------------
Project Capital Area                                                    US$M
----------------------------------------------------------------------------
Infrastructure                                                           7.5
Power Plant                                                              7.8
Mining and Support Equipment                                            24.8
Process Plant (incl. water system)                                      98.7
Indirects (i)                                                           14.1
Resettlement                                                            10.3
EPCM, Commissioning and Owner's Cost (i)                                29.3
Pre-production (i) (w/OCR and preproduction Gold credit(ii))            30.5
Working Capital                                                         10.2
Contingencies                                                           16.7
Total Initial Capital Costs                                           $250.0
----------------------------------------------------------------------------
(i) Including contingency                                                   
(ii) Excluding VAT                                                          
(iii) Gold credit is for gold produced during the pre-production period of  
 commissioning equipment and amounts to approximately 8,400 ounces.         
----------------------------------------------------------------------------
 

 

 

Sustaining Capital & Closure Cost Estimates

 

 
 
----------------------------------------------------------------------------
Project Sustaining & Closure Capital Area                               US$M
----------------------------------------------------------------------------
Mining and G&A                                                          23.1
----------------------------------------------------------------------------
Plant & Nested Tails                                                    36.1
----------------------------------------------------------------------------
Resettlement                                                             9.9
----------------------------------------------------------------------------
Contingencies                                                            6.1
----------------------------------------------------------------------------
Total Sustaining Capital Costs                                          75.2
----------------------------------------------------------------------------
Reclamation and Closure(i)                                              13.8
----------------------------------------------------------------------------
Total Sustaining and Closure Capital                                    89.0
----------------------------------------------------------------------------
(i)Total closure cost estimated at $22.5M. $8.7M of expensed costs for heap 
 rinsing not included in closure capital as gold production is associated   
 with the process.                                                          
----------------------------------------------------------------------------
 

 

 

Sustaining capital costs were estimated on the basis of quotes on equipment from potential providers. Taxes and freight are included along with the individual items. The closure and reclamation plan includes work to be conducted from the closure of the mine at the end of operating activities, as well as progressive rehabilitation work during the life of the mine. The goal is to return the site to a satisfactory state as quickly as possible in terms of reducing the risks for health and safety, controlling erosion and developing a profile compatible with the future uses of the site.
 

Total LOM reclamation and closure costs are estimated to be $22.5 M including $8.7 M in expensed operating costs for heap rinsing in year 12. The additional $13.8 M in capital and $8.7 M in expenses are included in the LOM AISC estimate of $678/oz. An estimated equipment salvage value of $9.6 M has been included as a credit.
 

Project Sensitivities
 

The project is sensitive to gold price as demonstrated in the following table:

 

 

 
 
-------------------------------------------------------=======--------------
                                                          Base              
                                                          Case              
Gold Price (per oz)                        $1000  $1100  $1250  $1400  $1500
----------------------------------------------------------------------------
To Orezone                                                                  
NPV (0%) After tax ($M)                    121.2  198.5  323.9  437.1  519.8
NPV (5%) After tax ($M)                     49.1  105.1  196.1  278.2  338.1
IRR After tax                              10.4%  16.1%  24.4%  31.3%  36.2%
                                                                            
----------------------------------------------------------------------------
To Gov't Burkina Faso (incl taxes,                                          
 dividends and royalties)                                                   
NPV (0%) After tax ($M)                     99.1  149.1  214.8  292.6  337.3
NPV (5%) After tax ($M)                     69.8  105.7  152.7  208.5  240.6
----------------------------------------------------------------------------
----------------------------------------------------------------------------
 

 

 

The project is also sensitive to operating costs, in particular fuel (diesel and HFO) which accounts for approximately 25% of expenses. Diesel pricing is set by the government of Burkina Faso. The Study uses the conservative delivered to site fuel prices of $1.20/L for diesel and $0.77/L for HFO. Although diesel prices are lower than those used in the 2014 PEA, they are not as low as the current price in Burkina Faso or the free market price. The project economics and other mining operations in the country would benefit if the government were to change their policy to allow free market pricing and direct supply.
 

Mine Plan and Pit Optimization Studies
 

The Company has worked with RPA to develop a mine plan and production schedule (based on the April 2013 resource model). Scheduling has been optimized for project returns by processing the higher grade ore in the early years and stockpiling the lower grade ore for processing after mining is complete in year 8. Initial process grade for years 1 through 3 averages 1.08 g/t, with the years 1 through 8 averaging 0.88 g/t. A fleet of 32 tonne haul trucks, such as Volvo or Scania rear-dump units, will be used to provide increased versatility, as the mine plan consists of a large number of shallow pits of varying tonnage.
 

Total ore processed, including the lower grade stockpiles, will be 59.9 Mt of oxide and semi-oxidized ore grading an average of 0.76 g/t. The life of mine strip ratio is approximately one tonne of waste per tonne of ore.
 

Metallurgical Test Results
 

KCA has completed all of the metallurgical testing associated with the Bombore project Study and have reviewed the historical data. Results indicate that the overall recovery for the combined heap leach and CIL processing circuit is expected to be 87%. The circuit separates the fine ore (-212 micron) from the coarse ore in a cyanide solution via a rotary scrubber, screen and classifiers. The slurried fine ore (49% of the total) is pumped to a CIL circuit for gold recovery without any grinding. The CIL tails are sent to a lined tailings facility that utilizes the heap leach as part of the containment system in order to reduce the footprint and liner costs. The tails facility is designed to be zero discharge. The coarse (+0.212 mm) fraction is conveyed to a standard heap leach pad, where it is leached with a cyanide solution. With the majority of the fines removed from the coarser heap leach ore, there is no requirement for cement agglomeration or inter-lift liners for a stacking height of up to 60 m. The pregnant liquor from the heap leach is sent to the CIL circuit for gold recovery. Gold is recovered in a standard carbon desorption plant, finishing with electrowinning and smelting to produce gold dore bars.
 

Maximum power requirement will be 7.2 kWh/t ore. Overall reagent consumptions are given in the table below.
 

Reagent Consumption

 

 
 
----------------------------------------------------------------------------
Reagent                                                          Consumption
----------------------------------------------------------------------------
Cyanide                                        0.4 kg/t Heap; 0.165 kg/t CIL
----------------------------------------------------------------------------
Lime                                                               1.24 kg/t
----------------------------------------------------------------------------
Caustic                                                            25.9 t/yr
----------------------------------------------------------------------------
Carbon                                                               52 t/yr
----------------------------------------------------------------------------
 

 

 

Development Timetable
 

Estimated time to construct the Bombore operation (pre-production) is 21 months, including time to excavate the Off Channel Reservoir (OCR) to be used for project water storage, and time to commission the process plant equipment.
 

Water for the operation will be collected by gravity feed into the OCR from about 10% of the annual rainy season runoff from the Nobsin River drainage basin. The OCR usable volume design capacity is 3 M cubic meters, and significantly larger than those designs presented in the 2014 PEA (0.9 M cubic meters). Annual water consumption for the project is calculated to be, on average, between 2.6 M and 2.9 M cubic meters per year and considers recycle of tailings solution. The increase in annual water consumption as compared to the 2014 PEA is due to the change in the process from 100% Heap Leach to a combined Heap Leach/CIL process.
 

Environmental Studies and Social Responsibility
 

The Environmental Baseline Studies for the Bombore Project began in 2011 and were completed at the end of 2014. Local consultants have conducted archaeological studies and a comprehensive range of environmental and social impact studies. Their work is supported by WSP who were retained by Orezone early in 2014 to support and audit the Bombore ESIA study and resettlement action plan.
 

Over the past 5 years the Company has recognized and accepted its social responsibility by actively supporting local communities by sponsoring over 50 initiatives which included improvements and additions to local schools, clinics, water wells and supply inventories. Orezone have on staff technically qualified personnel, sociologists and managers experienced with mining and resettlement projects in Burkina Faso. With the help of our employees, consultants and community leaders the Company is currently developing plans to pursue these community projects in the coming weeks, months and years.
 

The Company continues to hold formal and informal information meetings with the community leaders to update them regularly on the status of the Bombore study. In order to ensure safe operations, the project will require the relocation of over 500 local households (approximately 3,700 residents) from several communities and two artisanal mining sites over the initial 5 years of construction and operation. The program for this relocation has been the object of joint discussions involving the communities affected, their representatives, the Company and its local consultants Socrege. A detailed analysis based on these discussions has led to a substantial increase in relocation and resettlement cost as compared to the 2014 PEA. The main areas where estimated costs increased were building replacement, artisanal miner compensation, infrastructure crop and tree compensation and livelihood compensation. Pre-production costs for the resettlement program are now estimated at $10.3 M, with life of mine costs estimated at $20.2 M.
 

Full details of the Feasibility Study in the form of a NI 43-101 technical report will be filed on SEDAR within the next 45 days. The Company is also in the process of updating the 2013 Mineral Resource estimate with the inclusion of an additional 50,000 m of drilling. The update will be completed by Q3 2015 and if warranted, an update to the Mineral Reserve and mine plan will be completed prior to any production decision.
 

About Orezone Gold Corporation
 

Orezone is a Canadian company with a gold discovery track record of +12 Moz and recent mine development experience in Burkina Faso, West Africa. The Company owns a 100% interest in Bombore, the largest undeveloped oxide gold deposit in West Africa which is situated 85 km east of the capital city, adjacent to an international highway. The Company is the process of updating the Mineral Resource estimate, completing the Feasibility Study and filing an application for a mining permit on Bombore in H1 2015.

Posted April 29, 2015

Share this news article

MORE or "UNCATEGORIZED"


VIZSLA SILVER AGREES TO ACQUIRE NEWLY CONSOLIDATED PAST-PRODUCING SILVER DISTRICT IN THE EMERGING SILVER-GOLD-RICH PANUCO - SAN DIMAS CORRIDOR IN MEXICO

Vizsla Silver Corp. (TSX-V: VZLA) (NYSE: VZLA) (Frankfurt: 0G3) i... READ MORE

March 28, 2024

Additional Drill Results Highlighted by Hole D-380 in Block 6 at Oko West, Intersecting 39.7 m Grading 5.27 g/t Au Including 2.8 m @ 14.18 g/t Au and 13.0 m Grading 10.50 g/t Au

Reunion Gold Corporation (TSX-V: RGD) (OTCQX: RGDFF) is pleased t... READ MORE

March 28, 2024

STLLR Gold’s Tower Gold Project Infill Drilling Continues to Confirm Mineralization at the Jonpol Deposit

STLLR Gold Inc. (TSX: STLR) (OTCQX: STLRF) (FSE: O9D) announces ... READ MORE

March 28, 2024

Hudbay Provides Annual Reserve and Resource Update and Production Outlook

Consolidated copper production is expected to average 153,000i to... READ MORE

March 28, 2024

Aya Gold & Silver: Record 2023 Production, Revenue and Operating Cash Flow

Aya Gold & Silver Inc. (TSX: AYA) (OTCQX: AYASF) is pleased t... READ MORE

March 28, 2024

Copyright 2024 The Prospector News