The Hope Bay deposits are considered to be typical of orogenic gold deposits. In Canada, orogenic deposits represent the main source of gold and are typically located in the Archean greenstone belts of the Superior and Slave provinces.

GOLD MINERALIZATION AT THE DORIS AREA.
The Doris Vein system is characterized by a series of north–south striking, subvertical, goldbearing, ductile-brittle structures that commonly host wide, stylolitic, ribboned, or bull quartz veins. A total of nine sub-parallel structures have been identified within the Doris system. The most significant from west to east are: the West Valley Wall set, C/2 Stringer zone, Central, Lakeshore, and Island veins. Gold bearing structures have been traced by diamond drilling for over 2.3 km and to a depth of 650 m.

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 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.

GOLD MINERALIZATION AT MADRID AREA.
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 multistage 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.

GOLD MINERALIZATION AT THE BOSTON AREA.
Gold mineralization at the Boston deposit is present in sub-vertical horizons of extensive hydrothermal alteration within a large iron-rich carbonate-altered shear zone. Organic carbon graphite is a common component of the Boston mineralized system. Gold occurs within and around structurally controlled quartz-carbonate veins, which have been developed along lithological contacts. Gold is associated with sulphide mineralization, mainly as clots of the pyrite within veins as well as in the wallrock. Three major zones of the gold mineralization have been identified: B2, B3, and B4 zones. Each zone is over one kilometre in length and is composed of numerous narrow quartz-carbonate veins with disseminated pyrite. The veins are from 0.05 m to 3.0 m wide and of variable lengths within a 10 m to 40 m wide mineralized zone.

During 2018 and 2019 a small open pit was mined near Doris Lake where the hinge outcropped at surface.

A small open pit is currently being mined on the Naartok East Limb.

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.

From 2015 to 2017, ore produced by the Doris Mine was stockpiled while the first concentrator line of the Doris Plant was constructed. Construction of the first concentrator line of the Doris Plant was completed in December 2016 and commissioning completed in June 2017. The first concentrator line provided the Doris Plant with a capacity of 1,000 t/d. The Doris Plant capacity was upgraded to 2,000 t/d when the planned second concentrator line was completed in August 2018. The Doris Plant initially consisted of two Python concentrator lines followed by a concentrate treatment plant (CTP) which produces gold dore bars for sale. The Doris Plant has been upgraded from its original design with expanded gravity recovery and leach scavenger capabilities. [p. 72-73]

ORIGINAL DESIGN CRITERIA
- Concentrator availability was 92% (8,059 hours per annum), which included availability in the CTP.
- CL feed was 2 x 62.5 t/h (IPJ con bypassed mill), 9.8 g/t, 2 x 605 g/h Au.
- ........