Gold Reach Resources Announces Positive Preliminary Economic Assessment For Ootsa Project

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By peterc on May 24, 2016. No Comments

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Gold Reach Resources (TSX-V; GRV) (“Gold Reach” or the “Company”) is pleased to announce the summary results of an independent Preliminary Economic Assessment (“PEA”) on the Company’s 100% owned copper-gold-molybdenum Ootsa Project (“Ootsa Project”) in west-central British Columbia. The conceptual study demonstrates the potential to develop the Ootsa Project by means of contract mining and toll milling at low initial capital cost to deliver a base case after-tax NPV and IRR of C$186 million and 81% respectively. P&E Mining Consultants Inc. (“P&E)” was the lead engineering firm for the PEA, which also included input from Knight-Piesold Consulting, ERM Consultants Canada Ltd., and Gold Reach personnel.

“The Company is very encouraged with the outcome of the PEA”, said Gold Reach President and CEO Dwayne Melrose.  “The results of the PEA support the concept that the Ootsa Project can be developed as a potential profitable, low-cost investment with an anticipated future upturn in metal prices”.

Operating Plan

The conceptual operating plan for the Ootsa Project is based on the sequential, open pit development of three deposits in close proximity to each other, by a mining contractor.  Crushed mill feed will be transported from Ootsa to the adjacent mill by means of an overland conveyor system employing a series of floating conveyor units to cross an intervening reservoir.  Preliminary metallurgical testwork indicates that the Ootsa feed could be processed at a rate of 5.6 Mtpa achieving copper recoveries of 90-92%.  Processing would be conducted on a toll-basis.

Mineral Resources

An updated mineral resource model was developed utilizing a drill hole database comprised of 26,995 assays from 258 drill holes, including 7,311 m of drilling in 11 holes performed after the previous resource update.   Drill hole assay data was composited into 2 m intervals and a block model with 10 m by 10 m by 10 m block size was constructed using Gemcom modeling software.  Mineralized domains for all deposits were constrained incorporating geological, structural, and lithological parameters and using a $10/t NSR cut-off value.  Within these domains, a $8.50/t NSR cut-off value was applied to define the extent of mineralization with reasonable prospects for economic extraction.  Within these domains, grades for copper, gold, molybdenum, and silver were estimated using inverse distance squared (ID2) grade interpolation guided by geostatistical analysis.  The resulting resource model was subject to pit optimization using a Lerchs-Grossman algorithm to define a pit constrained mineral resource as detailed in the table below.

The updated mineral resource estimate for the Ootsa Project marks a large increase in resource confidence. Measured resources at the Ox deposit have increased from 11 Mt in the January 9, 2014 resource update to 31 Mt in the current update, an increase of 188%. The copper equivalent grade has also increased for the Measured category at Ox going from 0.34% Cu Eq (comprised of 0.21% Cu, 0.04 g/t Au, 0.029% Mo, and 1.6 g/t Ag) in the January 9, 2014 resource update to 0.37% Cu Eq (comprised of 0.26% Cu, 0.04 g/t Au, 0.028% Mo, and 1.5 g/t Ag) in the current estimate.  Measured resources at the East and West Seel deposits have increased from 28 Mt in the January 27, 2014 resource update to 157 Mt in the current update, an increase of 463%.  At the East Seel deposit the Cu Eq grade in the Measured category has increased slightly from 0.42% Cu Eq (0.25% Cu, 0.26 g/t Au, 1.5 g/t Ag) in the January 27, 2014 resource update to 0.43% Cu Eq (0.28% Cu, 0.26 g/t Au, 2.5 g/t Ag) in the current estimate.  At West Seel the Cu Eq grade in the Measured category has decreased slightly, from 0.40% Cu Eq (0.21% Cu, 0.15 g/t Au, 0.021% Mo, 3.8 g/t Ag) in the January 27, 2014 resource update to 0.37% Cu Eq (0.21% Cu, 0.16 g/t Au, 0.022% Mo, 3.2 g/t Ag) in the current resources estimate.


The conceptual mining plan uses conventional truck/shovel open pit methods employing an equipment fleet supplied and operated by a mining contractor.  Three pits will be mined sequentially over a period of 12 years including pre-stripping with mill feed conveyed to the nearby mill for processing.  Total mined tonnage will vary from 10-20 Mt annually depending on waste removal requirements.

The mill feed is contained within an optimized subset of the mineral resource set out in the table above.  Collectively, the three pits contain 65 Mt of mill feed (inclusive of mining dilution and loss factors) averaging 0.37% Cu Eq (0.25% Cu, 0.13 g/t Au, 0.016% Mo, and 2.3 g/t Ag).  The mill feed is associated with 31 Mt of overburden and 65 Mt waste rock resulting in an overall life of mine strip ratio of 1.46:1.  It is notable that all mineral resources considered for mining are classified in the Measured and Indicated categories.


The nearby mill is expected to be able to process mill feed from the Ootsa Project without modification.  Material will be processed on a toll-basis at a rate of 5.6 Mtpa.  Metallurgical recoveries are based on preliminary testwork and vary by deposit as shown in the table below.

Mill feed will be supplied to the mill via a conveyor system owned by Gold Reach and operated by the mining contractor.


The Ootsa Project lies on the south shore of the Nechako Reservoir, 6 km from the existing Huckleberry copper-molybdenum mine.  As such, road access, process plant, tailings storage, camp, and other support facilities already exist to support development.  Crushing, conveying, and field maintenance infrastructure will be established on the Ootsa side of the reservoir to support mining.  The added electrical load is estimated to be less than 2 MW and is expected to be supplied by the existing power line.

Access across the 1 km wide reservoir for equipment and personnel will be by a barge similar to the one that currently exists to facilitate logging operations on the Ootsa side of the reservoir.  Mill feed will be transferred from the mining areas to the mill via a conveyor system 9 km in length.  A series of floating conveyor units (similar to those often utilized by dredging contractors) integrated with the overland components will permit mill feed to move in a seamless, low-impact manner across the reservoir at a nominal average rate of 700 tph.

Capital Costs

The project development requires initial capital of C$64 M to construct the conveyor system, mobilize the contract mining fleet, prepare the first deposit for mining, and cover the cost of reclamation bonding.  An additional C$32 M in sustaining capital is required over the life-of-mine.  A contingency in the amount of 30% has been applied to all direct and indirect costs excluding pre-stripping.  A contingency has also been factored into the reclamation bond estimate separately.

Operating Costs

Unit operating costs used to determine Project value can be found in the table below.  Mining costs vary by material type and pit due to differences in haul distance, drill-blast cost, and the cost to transfer feed to the mill.   Processing costs vary from deposit to deposit based on differences in reagent consumption derived from testwork.  The total premium imposed on mining and milling costs for contract operation is approximately 30% and includes amortization, depreciation, administration, and margin. It is the opinion of P&E that the contract rates are consistent with industry norms and appropriate for the Ootsa Project.

Environmental and Social

Total reclamation and closure costs are estimated at $9 M for the Ootsa Project including decommissioning and post-closure monitoring.  Preliminary testwork indicates that water from mining areas will meet discharge requirements without the need for complex treatment.  None of the proposed development is expected to directly alter any potential commercial, recreational, or Aboriginal fisheries within the reservoir.

Construction and mine development are expected to employ about 140 people during the 12 month pre-production period.  More significant, however, is that the development could secure longer term employment for the existing mine workforce and the benefits it brings to the local community for an additional 12 years.  First Nations bands in the area are supportive of responsible development and have engaged in positive dialogue with Gold Reach throughout the exploration phase of the Ootsa Project.

Project Schedule

As contemplated in the PEA, engineering, environmental studies, and permitting of the Ootsa Project are   expected to take 3-4 years.  Construction would last 12 months during which infrastructure will be installed and the first pit pre-stripped.  Mining and processing would commence thereafter and continue for a period of 12 years.  At the end of operations, decommissioning would take 12-18 months followed by a minimum 5-year period of post-closure monitoring.


Financial performance is evaluated from the start of construction and does not consider the cost of permitting or financing.  The Ootsa Project has been evaluated using a 5% discount rate as, unlike many new mines, the development is premised on a tolling arrangement for the use of the adjacent Huckleberry assets, which obviates the risk associated with establishing access and constructing a mill and tailings facility.

Economics for the Ootsa Project are based on metal prices of US$3.00/lb Cu, $1,260/oz Au, $10.30/lb Mo, and $17.00/oz Ag, and at an exchange rate of C$1.00 = US$ 0.80.  Metal prices applied to the project represent a discount to prices projected for 2020 and beyond by various major financial institutions and forecasters.  This timing corresponds to when it is reasonably expected that the Ootsa Project could commence production.

The Ootsa Project has an estimated after-tax net present value (NPV) discounted at 5% of C$186 M, an internal rate of return (IRR) of 81%, and an undiscounted payback of 1 year.  The table above shows how the Ootsa Project value varies with changing metal prices and exchange rate.  The correlation between metal prices and exchange rate is a major contributor to the Ootsa Project’s resilience at lower prices.

Direct and all-in sustaining cash costs are US$1.33/lb Cu and US$2.09/lb Cu respectively.  Direct cash costs refer to all on-site costs of production while all-in sustaining cash costs are all costs of production including sustaining capital.  All cash costs are calculated net of by-product credits.

Conclusions and Recommendations

P&E concludes that the Ootsa Project has economic potential as an open pit mining operation, utilizing the Huckleberry processing plant to produce copper and molybdenum concentrates. The PEA outlines 65 Mt of mill feed (inclusive of mining dilution and loss factors) averaging 0.37% Cu Eq (0.25% Cu, 0.13 g/t Au, 0.016% Mo, and 2.3 g/t Ag) within 3 pits.  The mill feed from the updated mineral resource estimate supporting this tonnage has a high level of confidence with 94% (61 Mt) occurring within the Measured category and 6% (4 Mt) occurring in the Indicated category with no Inferred resources in the mine plan.  The Ootsa Project has a low capital cost at C$64 million, a low strip ratio at 1.46:1, and robust economics with an after-tax NPV of C$186 million, an after tax IRR of 81%, and 1 year payback period using base case metal prices.

In the PEA, P&E recommends that Gold Reach advance the Ootsa Project with extended and advanced technical studies with the intention of moving the project toward a production decision.

QP Statement

The resource update and Preliminary Economic Assessment have been completed by P&E Mining Consultants Inc. in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects.  The updated mineral resource estimate has been prepared by Brian Ray, P.Geo. and Eugene Puritch, P.Eng., both Independent Qualified Persons as defined by National Instrument 43-101, and has an effective date of January 1, 2016.  The Preliminary Economic Assessment has been prepared under the supervision of Eugene Puritch, P.Eng, an Independent Qualified Person as defined by National Instrument 43-101, and has an effective date of January 1, 2016.  The PEA will be filed on SEDAR within 45 days of this news release.


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