The Scotia Mine - Overview
100% owned, permitted operation with fully built mine and mill
The land associated with the mining leases are owned outright by ScoZinc Limited (subsidiary of EDM)
Excellent infrastructure in place - buildings/roads/power/water
Close to Halifax International Airport and all-season shipping ports
Long mine life with NI 43-101 Mineral Ore Reserves
Additional untapped Mineral Resources on adjoining mine lease and exploration licences
Completed updated PFS with very attractive economics:
Pre-tax NPV @ 8% of C$174 million and IRR of 69%
For more information on the Scotia Mine, its 2021 updated PFS highlights, location, history, geology, mineral resources and reserves, concentrate marketing and infrastructure please see below.
Updated Pre-Feasibility Study Highlights
Location & Ownership
The Scotia Mine consists of a fully permitted mine and mill which are 100% owned by ScoZinc Limited, a wholly owned subsidiary of EDM Resources. The Scotia Mine is located at approximately 45°02′ North, 63°21′ West, or 62 kilometres northeast of Halifax, Nova Scotia, in the Halifax Regional Municipality. Year-round access to the Project is by paved highway roads and is approximately 15 kilometres off the Nova Scotia provincial highway along Route #224. The Halifax International Airport is located 33 kilometres southwest of the mine site. The Project consists of 648 hectares of mineral rights in the form of three contiguous mineral leases, including land with exploration potential for zinc and lead mineralization. EDM Resources also owns real estate property of 712.5 hectares, which includes the mineral leases and adjoining areas.
ScoZinc Limited (EDM subsidiary) also currently holds five exploration licenses covering 41 claims in the immediate vicinity of the Scotia Mine Deposit. Each individual claim covers an area of approximately forty acres (16.2 hectares). In total, the 41 claims cover approximately 664 hectares (1,641 acres). These licenses are located along strike from the Scotia Mine Deposit and include favourable host rocks similar to that at the mine site.
All dollar amounts are expressed in Canadian Dollars unless otherwise noted
1 After Lead credits deducted
2 All-In-Sustaining-Costs (“AISC”) are C1 Costs plus Sustaining Capital and Financing Costs
Zinc and Lead mineralization was discovered at the Scotia Mine in 1973 by the Esso and Cuvier joint venture. Esso initiated mine development in 1978, commissioned the mill in 1979, developed the underground mine, and began mining and milling.
Seabright acquired the Scotia Mine property and mill in 1984. Seabright converted the mill for gold processing and processed gold ore from several satellite properties.
The Scotia Mine property was acquired in 1988, by Westminer Canada Limited, the Canadian subsidiary of Australia based Western Mining Corp. Westminer dewatered the mine and continued mining and milling.
In 1997, Savage Resources Canada Limited acquired the Scotia Mine assets from Westminer. Savage concluded that an open pit operation was feasible and initiated environmental permitting.
Savage was subsequently taken over by Pasminco Resources Canada. Regal Mines Limited purchased Pasminco Resources in February 2002. Regal Mines was owned 50% by OntZinc Corporation and 50% by Regal Consolidated Ventures Limited. As part of the sale, Pasminco Canada Holdings Inc. retained a 2% net smelter return (NSR) royalty on future production. In December 2002, OntZinc acquired Regal Consolidated’s 50% interest to own 100% of Pasminco Resources. Savage Resources Limited was the successor of Pasminco Holdings and held the 2% royalty.
OntZinc later changed its name to HudBay Minerals Inc. after purchasing, through reverse takeover, Hudson’s Bay Mining and Smelting in December 2004. Hudbay owned the Scotia Mine through its wholly-owned subsidiary, ScoZinc Limited.
In 2006, Acadian Gold Corp. purchased 100% of ScoZinc Limited and all of its assets (consisting mainly of the Scotia Mine and its infrastructure) from OntZinc for $7 million. Acadian Gold subsequently changed its name to Acadian Mining Limited. On 29 May 2007, ScoZinc Limited exercised its option to buy-out the 2% NSR for $1,450,000.
Acadian Mining reactivated the mill and continued surface mining the deposit during 2007 and 2008. Depressed metal prices and high operating costs forced Acadian Mining to place the mine on care-and maintenance status.
In May 2011, Selwyn Resources Limited (name changed to "ScoZinc Mining Ltd." in 2015) purchased ScoZinc Limited and all of its assets, including the Scotia Mine and Acadian Mining/ScoZinc Limited’s exploration claims, for $10 million less a deduction relating to increased reclamation bonding requirements that were being determined at the time of the acquisition.
In August 2019, new management of ScoZinc Mining Ltd. (now EDM Resources) was appointed to consolidate all previous work and develop a definitive plan for re-starting the Scotia Mine as quickly as practicable.
Geology & Mineralization
The Scotia Mine Deposit consists of three main zones of mineralization referred to as the Main (formerly Gays River deposit), Getty and Northeast Zones. The Main zone lies along the southside of the Gays River main branch, immediately east of the confluence with the Gays River south branch. The Getty zone lies just northwest of the Main and North-East zones on the western side of Gays River. The two zones are separated by less than one kilometre.
The Gays River Formation mineralization has long been considered a Mississippi Valley-type lead-zinc deposit. This type of deposit is carbonate-hosted, classified as a typical open space filling type, and hosted in a dolomitized limestone. The limestone developed as a carbonate build-upon an irregular pre-Carboniferous basement topographic high where conditions allowed for growth of reef-building organisms.
The zinc/lead-bearing Gays River Formation trends in an east-north east direction across the Property. Locally, the mineralisation dips up to 45º on average, and up to vertical in places, to the north-northwest which is the depositional slope of the front of the Gays River reef unit. The dip tends to be horizontal in the back reef area (south of the main trend). The mineralisation is present as sphalerite and galena and grades from massive Pb-Zn mineralized material in the fore reef to finely disseminated, lower grade material in the back reef. In the mine area, the Gays River Formation is overlain either by the evaporites of the Carroll’s Corner Formation and/or overburden.
Exploration and Data Management
The Scotia Mine has extensive diamond drilling and blast-hole drilling on a large portion of its mining leases and associated exploration licences. A total of 1,831 holes or 121,870 metres has been drilled to date. All of the data from these holes has been included in the 2020 Pre-Feasibility Study ("2020 PFS") and the 2019 Mineral Resource Estimation (“2019 MRE”).
For the Scotia Deposit, EDM owns the real property covering all the defined mineral resources on the mining leases, so no royalty to any landowner is applicable. However, there is a small 25-acre portion on EDM’s real property that is subject to a sand, gravel and fill royalty.
For the Getty deposit, EDM has a royalty with Globex Resources Ltd. EDM’s PFS indicates that such a royalty would only be applicable in the last few years of the 14-year mine life.
Nova Scotia provincial royalty of 2% also applies on all net revenue generated from the Project.
Mineral Resource Estimate
A Mineral Resource estimation was completed in December 2019 for the Scotia Mine Deposit, including the Main, Getty and Northeast Zones (“2019 MRE”). The mineral resources for the Scotia Mine Deposit have been classified as Measured, Indicated and Inferred categories based on CIM Definition Standards in accordance with NI 43-101 reporting guidelines, and are reported with respect to cut-off values calculated using the assumed processing costs and recoveries, and metal prices. The resource is also constrained by an optimized (WhittleTM) pit shell, which is based on optimistic metal prices, in order to demonstrate that the defined resources have reasonable prospects of eventual economic extraction, which is a CIM Definition Standards criterion.
The Scotia Mine Deposit mineral resource summary statement in provided in the table below, with an effective date of March 22, 2021.
The 2019 MRE resulted in an increase in Measured & Indicated tonnage of 105% (to 25,450,000 tonnes at a Zinc equivalent grade of 2.84%) and an increase in Inferred tonnage of 7% (to 5,010,000 tonnes at a Zinc equivalent grade of 2.13%) from previous resource estimates on the deposit.
An extract of the NI 43-101 Mineral Resources estimate for the Scotia Deposit (Main Deposit and North-East Deposit) and the adjoining Getty Deposit are provided below. Photographs of high-grade and medium grade rock samples previous mined as ore is also provided below.
For more information, please view our 2019 MRE NI 43-101 Technical Report on the Scotia Mine.
A Mineral Resources update was completed in March 2021, which includes a significant Gypsum mineral resource for the Scotia Mine.
The 2021 Mineral Resource Estimate (“2021 MRE”) focuses solely on adding Gypsum mineral resources based on the same optimized pit shell, for demonstrating reasonable prospects of economic extraction, as used in the 2019 MRE.
• Total Measured and Indicated Gypsum Mineral Resources of 5,180,000 tonnes at a Gypsum grade of 91.8%.
• Total Inferred Gypsum Mineral Resources of 790,000 tonnes at a Gypsum grade of 91.2%
EDM completed an updated technical report in March of 2021, which includes the Gypsum as a mineral reserve estimate in accordance with NI 43-101 guidelines, which further demonstrates the open-pit potential of the deposit with expected improved project economics with the Gypsum mineral resources included as a by-product.
Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability. There is no certainty that any part of the Mineral Resources estimated will be converted into Mineral Reserves;
Open-pit resources stated as contained within a potentially economically minable open-pit; pit optimization was based on assumed prices for zinc of US$1.35/lb, and for lead of US$1.14/lb, a Zn recovery of 86% and a Pb recovery of 93%, mining and processing costs varying by zone, and pit slopes of 45 degrees in rock and 22 degrees in overburden;
Open-pit resources are reported based on a Zinc Equivalent (ZnEq) cut-off grade of 0.90%. The ZnEq grade incorporates Zn and Pb sales costs of US$0.19/lb and US$0.11/lb respectively, and a 2% royalty fee;
Numbers in the table have been rounded to reflect the accuracy of the estimate and may not sum due to rounding.
Mineral Reserve Estimate
The Scotia Mine Mineral Reserves are classified as either Proven Reserves or Probable Reserves and are provided in the table below. Total Mineral Reserves are 13.66 million tonnes with a Zinc Equivalent grade of 3.09 percent.
For more information, please view our 2021 Updated Pre-Feasibility Study NI 43-101 Technical Report.
(1) Mineral Reserves were prepared by MineTech International Limited as independent Qualified Persons to NI 43-101 standards
(2) The Base Metal Mineral Reserves are as of 6 July 2020 and based on a design cut-off grade of 1.5% ZnEq grade. Cut-off grades are based on a Zinc metal price of US$1.10/lb, recovery of 89%, a Lead metal price of US$0.95/lb, and mining recovery of 92%. Average unplanned dilution and mining recovery factors of 12% and 92%, respectively, are assumed
(3) 2021 Gypsum Mineral Reserves are as of 16 November 2021 and based on a non-binding offtake agreement. The LOI has be reviewed and approved by Minetech International to satisfy the requirements for converting Gypsum resources into Gypsum reserves.
The Scotia Mine deposit covers a total strike length of approximately 4 kilometres, with some surface constraints in between, and a vertical distance of approximately 120 metres. All mining is from open-pit operations with an expected mine life of approximately 14 years. Mining operations will be conducted utilizing 4 shifts, 12 hours each shift, covering 24 hours per day. The 4 shifts will be on a 4-days on, 4-days off, 4-nights on, 4-nights off rotation.
The Scotia Mine mineral resources will be extracted using conventional load and haul (truck & shovel) mining methods as determined by optimized pit designs and life-of-mine schedules. Mining operations will be completed using an owner/operator of excavators, loaders, haul trucks and ancillary support equipment as well as some rental equipment. Equipment requirements have been determined based upon required production rates and haulage cycles using equipment specifications provided by local authorized equipment suppliers and manufacturers.
The open-pits will be mined on 5-metre-high benches with double benching being utilized on the lower benches which are primarily comprised of hard rock. Drilling and blasting are only required for 40 percent of the total material mined over the life of mine plan, which accounts for all of the hard rock to be mined from the pits. The remaining 60 percent is largely comprised of overburden and has been proved to be free digging material based on past operations and will not require blasting. Drilling and blasting will be performed using contract services.
The Ultimate Pit Design was divided into 6 phases to optimize development sequences and production requirements. Waste has been subdivided into overburden, gypsum, and carbonate waste rock. Inferred resource material inside the Ultimate Pit Design has been included as carbonate waste rock and totals approximately 1,450,000 tonnes at 1.5% Zn and 0.7% Pb. Waste storage will consist of a combination of backfilling the mined pits and stockpiling in the waste dump. Using the Ultimate Pit Design and the pit phase sequencing, a Life-Of-Mine (“LOM”) mining schedule was developed by month and is based on operating 24 hours/day, 365 days/year. The LOM production schedule is based on providing a mill feed of approximately 1 million tonnes per annum at an average grade of 2.03% Zinc and 1.10% Lead, which equates to a Zinc Equivalent grade of 3.09%.
The water table at the Scotia Mine is divided into two horizons: the overburden horizon and the bedrock horizon. ScoZinc plans to utilize 60 geotechnical depressurizing pumping wells, in conjunction with in-pit pumping via submersible sump pumps, to dewater the overburden horizon. The bedrock horizon will be dewatered using the existing deep well infrastructure in conjunction with in-pit temporary wells that access the underground workings. Horizontal wells will also be utilized in the karst gypsum to deal with the localized trapped water and will be allowed to drain into strategically placed in pit sumps which will then be pumped to the tailings storage facility (“TSF”). All in pit water will be pumped to the TSF. Water from the 60 depressurizing pit perimeter wells will be discharged into either a reservoir or the Gays River, however most of this water will be used as processing water in the mill. A similar setup will be utilized in the North East and Getty pits.
The figure below illustrates the ultimate open-pit and waste dump design.
Metallurgy and Mineral Processing
Metallurgical data from past production data and more recent metallurgical test work is available on the carbonate hosted zinc-lead deposit. The combined data shows that the zinc and lead minerals liberate well from the host rock, resulting in relatively high metal recoveries and concentrate grades. The simple mineralogy and metallurgy present the opportunity to consistently achieve high recoveries and concentrate grades over the life of mine plan.
The process design criteria, based on historical data and plant design improvements, include overall average zinc concentrate grades of 57% with an average 86.6% recovery, and the overall average lead concentrate grade of 71% with an average 89.1% recovery. Due to the carbonate hosted deposit, the zinc and lead concentrates have very low levels of impurities or deleterious minerals, resulting in the ScoZinc concentrates to be proven to be a clean, high-ranking concentrate.
The Scotia Mine concentrator plant (or Mill) was last operated in 2009 at 2,200 tonnes per day from the original name plate design of 1,500 tonnes per day using conventional crushing, grinding flotation, concentrate dewatering/drying, and rehandling loadout. After extensively reviewing all past production and incomplete engineering work, new final design work as part of the Pre-Feasibility Study has confirmed that with relatively minor upgrades to the comminution, flotation and dewatering circuits, the plant can consistently operate at 2,700 tonnes per day without major capital expansion.
The new PFS overall plant layout and plant flow diagram are provided in figures below.
The Scotia Mine’s carbonate-hosted orebody will produce high-quality zinc and lead concentrates through its 2,700 tonnes per day processing plant on the mine site. The concentrates will be loaded directly into lined 20’ shipping containers, which will be sampled, sealed and weighed on site. EDM personnel will transport the containers by all season highway to either the Fairview Cove Container Terminal or a nearby Canadian National Railway siding.
EDM has an initial offtake agreement by way of a Memorandum of Understanding, dated 3rd April 2018, with MRI Trading AG, for the Scotia Mine’s lead and zinc concentrates for approximately 10 years of the 14-year mine life. The agreement provides competitive terms for 333,000 wet metric tonnes of zinc concentrate and 133,000 of lead concentrate from the Scotia Mine. EDM expects to establish firm concentrate purchase contracts with one or more metal trading companies under terms consistent with the current market terms. EDM is engaged in negotiations with a number of offtakers but has not yet finalized an arrangement.
Existing Site Infrastructure
The Scotia Mine is conveniently located 33 kilometres from Halifax’s International Stanfield Airport (YHZ) in Nova Scotia with excellent infrastructure in place including processing facilities, waste dumps, a tailings pond, grid-power, all-season port terminal access, and all-season highways. Building infrastructure in place has an area of approximately 131,585 square feet. The mine site infrastructure is well established, as it has been on high level care & maintenance since 2009.
As the Scotia Mine is fully permitted for operations, relatively minor upgrades and improvements to the mining and processing facilities to enable the operation to commence commercial production within a relatively short time frame of months.
Electrical grid power systems are currently onsite with transformers and major motor control centres in place.
Water for mineral processing is provided from pit perimeter wells designed to un-saturate the pit slopes and to provide clean water to the plant for optimal water quality. Water may also be sourced from the tailings pond. Additional water is sourced from the nearby Gays River and treated for potable water site needs and fire suppression.
The Tailings Storage Facility is permitted with 8 million tonnes of capacity.
The Scotia Mine is located adjacent to sealed Highway 224, with a permanent 900 metre access road providing all season access to the operation. The Mine is located in the Halifax Regional Municipality, which is approximately 62 kilometres to downtown Halifax.
The transport and handling of freight and concentrate is possible year-round due to ScoZinc’s location on an unrestricted highway. The Scotia Mine is also located near a Canadian National Railway line siding, the Nova Scotia provincial highway (#102), deep-water ports and container handling terminals, and the Trans-Canadian National Highway.
Permitting, Environmental & Community
The Scotia Mine is an existing operation on high-level Care & Maintenance with substantial environmental databases, operating history, and valid permits and licenses that allow for the mining, processing of resources, and the shipping of zinc and lead concentrates.
Environmental responsibility and stewardship have been and continue to be a priority to EDM. To that end, there are extensive monitoring programs at the Scotia Mine including but not limited to: Surface Water quality, Groundwater quality, Wetland, Wildlife and Vegetation.
Roughly half of the mineral resources used in this economic analysis are already under permit and mining of those resources (Main Zone, Southwest Expansion).
Another important aspect of the project status with respect to permits, environment and community is that regulators and the community have experience with the project and environmental baseline conditions are already well understood.