The Hope Bay Property is located within the Hope Bay volcanic belt which is part of a massive structural-geological complex called the Slave Structural Province.

The Hope Bay deposits (Doris, Madrid, and Boston), as well as a large number of other prospects, are considered to be typical of orogenic-type mesothermal lode gold deposits, greenstone-hosted quartz carbonate vein deposits.

• The Doris gold deposit is a typical Archean lode deposit which occurs within an over 3 km long, steeply dipping quartz vein system, in folded and metamorphosed pillow basaltic rocks.
• The Madrid deposit area lies within a north-south striking package of mafic volcanic rocks, comprising a sequence of Fe-Ti tholeiitics, Mg tholeiitics, komatiitic basaltic, synvolcanic to late gabbroic, and ultramafic rocks.
• The geology in the area of the Boston deposit is a bimodal assemblage of mafic and felsic volcanic rocks in contact with sedimentary rocks, all of which are complexly folded about a large-scale synformal-anticline. The core of the anticline is occupied by mafic volcanic rocks that host the Boston deposit and these are in turn overlain by sedimentary rocks.

THE DORIS AREA
The Doris Deposit is located at the north end of the north-south trending Hope Bay greenstone belt of Archean age near Cambridge Bay in Nunavut. Gold mineralization is contained within predominantly sub vertical quartz veins hosted within mafic volcanic rocks.

The Doris Vein system is characterized by a series of north–south striking, sub vertical, goldbearing, brittle-ductile structures that commonly host wide, stylolitic, ribboned, or bull quartz veins.

Within the veins, gold is commonly associated with narrow tourmaline chlorite septa oriented parallel to and along the vein margins. Veins are not consistently mineralized along strike. Gold is distributed throughout vein structure but is usually concentrated near the footwall side of the vein, where visible gold is relatively common. Gold mineralization includes visible and disseminated gold occurring primarily with quartz veins ranging from a few centimetres to approximately 10 m in scale. Visible gold includes coarse leafy free milling grains located along vein margins, tourmaline septa, and wallrock fragments which are commonly associated with pyrite. Gold is also associated with disseminated sulphides at the margins of the quartz veins, or with sulphide clusters within the vein. Occasionally, gold is present within brecciated zones adjacent to the quartz veins. Sulphide mineralization consists of trace to 2% pyrite, trace chalcopyrite, rare sphalerite, and pyrrhotite.

THE MADRID AREA
The Madrid deposit area is located in the northern area of the Hope Bay volcanic belt, south of the Doris deposit. It includes the Wolverine-Madrid corridor which is defined as the belt of rocks extending from the southern end of Wolverine Lake to the northwest end of Patch Lake (Sherlock et al., 2002).

The Madrid deposit area includes the Naartok East, Naartok West, Rand, Spur, Suluk, Wolverine and Patch 14 deposits. The Madrid trend also includes the Suluk T3, and Patch 7 prospects.

The style of mineralization at Madrid is different from the Doris or Boston deposits and can be generally characterized by sulphidation and replacement of favourable stratigraphic units. The most favorable lithologies are Fe-rich tholeiitic mafic volcanics which have been extensively brecciated. Hydrothermal alteration at Madrid is characterized by an early assemblage of sericite micas and carbonate alteration, consisting of magnesite and ankerite with quartz-carbonate stockwork veinlets. The main gold-bearing alteration assemblage consists of secondary albite and paragonite with lesser carbonate as ankerite and quartz-ankerite stockwork veinlets. The higher gold tenor is associated with over 10% fine grained pyrite, intense albite flooding and hematite discoloration (Sherlock et al., 2012).

The gold mineralization within Naartok West, Naartok East, Rand, Suluk, and Patch 7 consists of quartz-carbonate stockwork veining, which overprints dolomite-sericite-albite-pyrite altered mafic volcanic rocks of the Patch Group. The gold mineralization is characterized by multi-stage brecciation and alteration with at least two separate gold mineralization events. Gold occurs within north-northeast, east, southeast, and north-northwest trending brecciated and carbonate altered zones and is associated with disseminated pyrite which has replaced brecciated mafic fragments

THE BOSTON AREA
Boston mineralization has been subdivided into the B2, B3, B4, and B5 zones.

The strongest mineralization in the Boston deposit is found within the B2 zone, particularly the section investigated by the underground workings. The B2 zone has been intersected to a depth of 1,000 m, with the highest grades located in the central part of the zone.

Compared with the B2 zone, mineralization in the B3 zone is less continuous and lower grade. The B4 and B5 zones are the smallest of the three main Boston ore zones. The B4 zone is a relatively small zone hosted on the eastern contact of the volcanic core, while the B5 zone comprises several mineralized horizons located south of the Newton Deformation Zone.

Fingas (2018) recognizes at least 6 styles of mineralization in the Boston deposit, which include: vein stringer sets hosted in transition breccia; discrete veins at geological contacts; fault-hosted veins; shear-hosted mineralization; vein domains at picrite contacts; internal picrite-hosted mineralization.

Vein stringer sets hosted in transition breccia is the most important mineralization style in the B2 zone and has been exposed in underground drifts. Mineralization consists of sulphide-bearing quartz-carbonate veins, typically hosted in both volcanic- and sediment-dominated transition breccia. Zones are typically planar, from 2 to 10 metre wide, with ore shoots plunging steeply to the southwest (e.g. ore shoots within the B2 zone with an apparent plunge of 77° to 225°).

Of the 16.8 Mt of ore produced during the LOM (2020-2034), the distribution by mine will include Doris at 7%, Naartok at 46%, Suluk at 22%, Madrid South at 5%, and Boston at 20%.

Current ore mining is ongoing at the Doris deposit and a small crown pillar recovery surface operation at the Madrid North deposit and advances to the Madrid North underground operation, Madrid South, Suluk and Boston deposits will occur sequentially over the defined Life of Mine (LOM).

Production for the Doris Plant LOM period (2020-2023) is on average 1,963 t/d from two mines including Doris and Madrid North (Naartok).

Production for the Madrid Plant LOM period (2024-2034) is up to 4,000 t/d from three mines including the Madrid North (Naartok, Suluk, Rand zones) the Madrid South (Patch 14 and Wolverine zones) and Boston.

Mining at the Hope Bay Project incorporates longhole mining methods in order to address the deposit geometry and anticipated ground conditions. Mining will take place under permafrost conditions where the mineralization is located away from any water bodies and under nonpermafrost conditions in what is known as the talik in the vicinity and under the lakes in the area.

Doris North will be under permafrost while the Connector and Central zones at Doris will be beneath the lake. A portion of the Madrid North deposit (part of Naartok) as well as the Madrid South deposits (Patch and Wolverine) are situated beneath the lakes and therefore will not be under permafrost conditions.

The deposits will be accessed, and services will be provided by a decline from surface with an average grade of 13%. The ramp will also be used for ore and waste haulage from the underground operations.

The Doris deposit is currently in production, with an existing ramp decline reaching active mining areas. Mining will continue as per current methods until depletion. Transverse and longitudinal longhole mining is planned for Doris. Madrid North (Naartok and Suluk) and Boston will be mined using longhole stoping methods with sub-levels placed at 20-m vertical intervals (16-m drilling heights). Both longitudinal and transverse accesses are used, depending on width of the ore zones. The Madrid South (Patch and Wolverine), where ore zones are much narrower, will be mined using longhole stope method with sub-levels placed at 16-m intervals (12-m drilling heights). The majority of stopes in Madrid South will have longitudinal accesses.

Sill pillars are placed throughout the deposit to improve the mining sequence by providing additional stoping fronts. Sill pillars will be recovered at the end of the sequence using up-holes.

Stopes will be backfilled using a combination of CRF and unconsolidated rockfill (UCF). The CRF will generally contain 5% binder, except 10% in sill pillars. The CRF will be mixed on surface and trucked to the stopes.

MINING METHOD
Sub-level longhole mining is forecast in all mining areas, with a combination of longitudinal and transverse stopes, depending on stope width. The use of Transverse Longhole mining was considered initially in the PEA study for the Madrid North Naartok zone, however, a review indicated that the large widths are made up of several veins with sufficient separation between them to allow a combination of Longitudinal and Transverse Longhole mining. Primary-secondary sequences are used in transverse stopes. Longitudinal stopes are planned with a retreat sequence towards a centre access.

The sub-level intervals were fixed at 20 meters for all the deposits except Patch and Wolverine where the interval is 16 meters to provide the required control for narrow lens of ore and the small diameter longholes that will be used. The nature of the veins did not appear conducive to the use of increased sub-level intervals and larger borehole diameters. The sub-level retreat (SLR) or longitudinal stoping method will be in use at all of the deposits. Stopes will be filled with a combination of CRF and unconsolidated rockfill.

The undercut drift and overcut drift are driven on ore and mining would start from the lower access retreating out towards the main access drift. Nominal stope strike lengths are 15 meters but will vary based on local geometry. Once a stope block is finished, CRF is introduced from the upper sub-level. CRF will be used until the fill covers all walls to be exposed with future mining; unconsolidated fill will be used for the remainder of the void.

Slot raises are drilled between three and four m from the previous stope to create the primary void. Most stopes will be drilled from the overcut downwards to the undercut. Upholes will be drilled to recover the level below the sill pillar, where a small “skin” will be left to prevent dilution of CRF.

Stope strike lengths are limited controlled in order to respect the HR values and prevent excessive dilution. This stoping system is advantageous by reducing waste development requirements but requires multiple active stoping sequences to maintain the planned production rate. Sill pillars are placed throughout the mine to divide the stope sequences.

The recommended drills are capable of drilling diameters from 50 to 89 mm in diameter. Drill holes of 63 mm are recommended for smaller stopes, combined with a tightly-space “dice-five” drill pattern. Larger diameter holes will be used in larger stopes with greater burden and spacing. Drill holes will be approximately 17m in length for most deposits, but 12 m at Madrid South.

Multiple veins are present in certain areas of the deposit. In some cases, spacing between the veins are sufficient to allow mining of each vein separately to minimize dilution. In some areas, particularly in Naartok and Suluk, the geometry is such that transverse stoping is more efficient. A primary stope sequence will be established in these areas, with secondary stopes later extracted.

Ammonium Nitrate/Fuel Oil (ANFO) is expected to be the primary blasting agent for both development and production, with standard Handidet detonators used for initiation.

Production for the Doris Plant LOM period (2020-2023) is on average 1,963 t/d from two mines including Doris and Madrid North (Naartok).

Production for the Madrid Plant LOM period (2024-2034) is up to 4,000 t/d from three mines including the Madrid North (Naartok, Suluk, Rand zones) the Madrid South (Patch 14 and Wolverine zones) and Boston.

DORIS PLANT (the currently operating processing facility)
The following is a summary of the proposed Doris Plant operation from 2020 to 2023. Ore will be sourced from the Doris and Madrid North (Naartok) deposits. The annual tonnage of ore processed is expected to be up to 730,000 t/a.

The plant recovers gold from the ore using a combination of gravity concentration and flotation. Flotation tailings, devoid of sulphides are sent to the TIA at a relatively coarse grind of 80% passing (P80) 150 µm. Gravity concentrates recovered by batch continuous centrifugal concentration are treated by intensive cyanidation ........