The Island Gold Property is located in the Michipicoten Greenstone Belt (MGB) which is part of the Wawa Subprovince within the Archaean Superior Province. The MGB is approximately 140 km long and up to 45 km wide. The metamorphic grade of the subprovince is greenschist but amphibolite facies can be seen locally or proximal to intrusions. A major regional deformation zone called the Goudreau Lake Deformation Zone (GLDZ) is situated throughout the area. It is a north-easterly trending structure which has been traced along strike for 30 km with a width of 4.5 km and believed to be the main control of gold mineralization for the Project area. It is a high angle oblique-slip fault zone with an overall dextral movement cutting stratigraphy at a shallow angle. There are three main splays to the GLDZ in the area, the southernmost of which hosts the Island Gold Mine structure which contains a stacked sequence of east-northeast striking, steeply dipping, and subparallel zones of gold mineralization.

Lithologies appear to form a conformable homoclinal volcano-stratigraphic sequence, facing and younging to the north in the project area. Tight to isoclinal folds and local attenuation or boudinage of units along fold limbs appear to occur regionally. Fold axes are subparallel to the regional
foliation at N070°E to N095°E.

The Island Gold Mine is stratigraphically positioned in the upper portion of the Wawa Assemblage, on the northern limb of the Goudreau Anticline. This assemblage is mostly composed of felsic volcanic rocks of various facies of tuffs and lavas.

Quartz veins commonly bear visible gold in the form of aggregates, disseminated fine grains or along chlorite-sericite slickensides within the veins. The degree of veining appears to change at depth, transitioning from a stringer style quartz-carbonate vein on scales between millimeter to
larger scale veins which can be over 4 metres in width.

The Island Gold deposit is composed of multiple, stacked, south dipping lenses. The mineralized corridor expands from 50 m wide in the upper levels to over 150 m wide at depth. The zone’s dip varies from sub-vertical to vertical from -50° to -90° south. Locally, north dip reversals occur but are not common. Rare instances of offset or folding have been seen. Around the 400 metre level there is a shallow dipping southern inflection of the mineralized zones. It is not yet clear if this inflection is related to a fault, a shear zone, or a fold. This inflection point is the division of what is locally referred to as the Upper Island Gold Mine and the Lower Island Gold Mine.

The Island Gold Mine is an Archean orogenic lode gold deposit. It is a structurally hosted quartzcarbonate vein system situated within the Goudreau Lake Deformation Zone (GLDZ), a major
regional brittle-ductile structure. The host terrane is a sequence of felsic to intermediate volcanic rocks of the Wawa Assemblage which are in the greenschist metamorphic range as is common
for this type of deposit. High strain zones associated with the GLDZ have the tendency to develop at variable scales along lithologic unit contacts where complex geology and related competency
contrasts can control stress patterns and facilitate shearing and the consequent development of dilatancy zones and concomitant quartz carbonate vein formation. It is generally accepted that
these Archean orogenic lode gold deposits are related to compressional and transpressional tectonics and the associated metamorphic dewatering and devolatization of magma processes
from which the gold bearing fluids are derived.

The Island Gold deposit is accessed via a single decline from surface down to the 425 Level, at which point multiple ramps are utilized to access the main IG, IG West, Extension and East zones. These ramps are also connected at numerous points throughout the mine allowing for easy travel between mining zones.

Presently, level accesses are designed towards the center of the ore vein and stopes are mined longitudinally from sill extremities towards the level intersection. As mining progresses deeper level accesses are designed to access the extents of the deposit with stopes being mined from the center towards the extremities to support improved mining stress management.

The mining method for a particular stope is selected based on a variety of factors such as overall geometry of the mineralization, width of the ore zone, local stresses, mapping and geotechnical data, spatial location of the stope, and existing nearby development and infrastructure. Other factors considered include equipment size and limitations as well as available fill type. Presently, stoping is undertaken with longitudinal open stoping (modified Avoca) and transverse open stoping. A limited amount of Alimak stoping will be undertaken, beginning in 2021.

Three different mine capacity rates were examined, 1,200 tpd, 1,600 tpd, and 2,000 tpd. The current mill capacity of Island Gold is 1,200 tpd and this case was deemed the Basecase for the Study. Early in the Study, grinding simulation work indicated that the installed grinding capacity of the mill is 1,600 tpd, although downstream processes would require upgrading for the mill to operate at that rate. It was therefore decided that the mid-range capacity scenario would be at 1,600 tpd. After mine planning in the scoping study work indicated that a 2,000 tpd mining capacity was a viable option, this scenario was added to the Study.

Two material handling options were examined: ramp ore and waste haulage and skipping ore and waste with a shaft.

Based upon these conclusions Island Gold is proceeding the permitting and construction of the paste plant, the shaft complex and mining at a rate of 2,000 tpd.

Shaft at 2,000 TPD with a Paste Plant (S2000)
The S2000 scenario anticipates sinking a 1,373 m deep shaft and increasing the mining rate to 2,000 tpd in 2026. Upon commissioning of the shaft and its associated infrastructure all ore and waste transport would be via the shaft. In addition, the shaft would be used to transport personnel and materials to any of the three shaft station levels thereby decreasing travel time significantly. The scenario has several significant capital investments including:

• The sinking of a 1,373 m deep, 5 m diameter, concrete lined shaft;
• Construction of a hosting plant and associated infrastructure. The design selected would be capable of hoisting 4,500 tpd or ore and waste from the 1,373 m elevation and 3,500 uj tpd of ore and waste from the 2,000 m elevation should the shaft be required to be deepened in the future to access new Mineral Resources. Details of the shaft and associated infrastructure are fully described in Section 18.3;
• Construction of an ore and waste handling system underground consisting of ore and waste passes, a grizzly, coarse ore bins, and a loading pocket;
• A paste fill plant, and the associated underground distribution system, capable of delivering 2,000 tpd of paste; and
• The mill capacity would be expanded to 2,000 tpd. This would require upgrades or additions to several of the areas of the process plant such as the crushing circuit, fine ore stockpile capacity, primary grinding circuit, pre-leach thickening, leaching, CIP, acid wash, process water management, and other equipment modifications.

As most of the ore will be moved on the level to the ore passes, the truck requirements are significantly reduced from current (2020) requirement of eight 42 tonne trucks. Five 42 tonne trucks will be required when the shaft infrastructure is in place.

Crushing Circuit Modifications
As part of the crushing circuit evaluation, several cases were simulated with varying run of mine particle size distributions in combination with two scenarios for the secondary crushing, namely a coarse closed side setting (CSS) of 75 mm and a fine CSS of 38-50 mm.

The outcome of the assessment recommended the installation of a new Metso TK9-42-2V vibrating grizzly feeder to relieve the load on the existing jaw crusher. Modelling was done with 56 mm slots, but 70 mm slots are suitable, as well. The oversize on the feeder will report to the
jaw crusher, while the undersize will report directly to Conveyor #2 via new chute work, thus bypassing the jaw crusher.

The new jaw crusher (Metso C96 or equivalent) will be capable of operating at up to 125 tph (i.e. 2,000 tpd at 67% availability) with a CSS in the range of 38-75 mm which provides sufficient size reduction for the existing HP200 cone crusher to maintain a crushing circuit product size (D80) of less than 11.7 mm.

It was observed that according to 2019 operations data, the cone crusher average power is 71 kW or 54% power utilization. This indicates that the crusher is not power constrained given the current crushing rates and crusher CSS and is capable of higher tonnages.

The existing sizing screen (100-SCR-001) is overloaded at 1,200 tpd, therefore it is recommended to install a double deck RF1848-2 screen (1.8 m x 4.8 m) for the increased tonnage. Note that a secondary crushing circuit availability of greater than 70% is required to utilize this size of screen.

To cater for the installation of the bigger screen, Conveyor #3 (100-CON-003) needs to be modified to discharge at a slightly higher elevation. The screen oversize discharge remains the same and reports to Conveyor #4 to report to the cone crusher, while the screen undersize reports to Conveyor #5 towards the stockpile.

Ore Storage Modifications
Downstream of the sizing screen is the fine ore bin, which has a 500 tonne live capacity which is sufficient for 1,200 tpd, however, when operating at 1,600 tpd or higher, the surge capacity in this bin is insufficient. Therefore, it is recommended to implement a new stockpile with a 1,000 t live capacity prior to the grinding circuit which would be adequate for operating at up to 2,000 tpd. The stockpile would be fed via a new 24” Fine Ore Transfer Conveyor which will be fed from the existing Conveyor #5. Conveyor #5 presently feeds the transfer tower, however, during a planned shutdown, it will be redirected to feed the new Fine Ore Transfer Conveyor.

The stockpile would be housed within a fabric building, complete with a concrete slab on grade to mitigate gold losses into the ground, and overhead doors to allow access for mobile equipment. A corrugated steel tunnel under the stockpile cover would be installed to allow for the installation of two in-line belt feeders to withdraw ore from the stockpile to two new 24” Fine Ore Reclaim Conveyors. The tunnel will run the length of the stockpile cover with the back end opening to up to surface to provide a second means of egress out of the tunnel. Fine Ore Reclaim Conveyor #1 will exit the front end of the tunnel and discharge onto the existing Conveyor #6. The conveyor will proceed to discharge into the existing Fine Ore Bin. With a level of surge capacity in the new stockpile, it will not be necessary to keep the Fine Ore Bin full, however, the option to do so is still available. Fine Ore Reclaim Conveyor #2 will exit the tunnel and discharge onto a new Ball Mill Feed Conveyor.


IIt should be noted that the existing 24” wide conveyors that are planned on being reused after he expansion can achieve up to 2,000 tpd throughput based on their belt width if they are sped up.

Grinding Circuit Modifications
To implement a parallel grinding circuit, a new, equivalent primary mill (3 m diameter x 5.79 m effective grinding length) is required. The grinding circuit makes use of the existing regrind mills.

The existing flat-bottomed cyclone should be replaced with screens since this unit is considered incapable of providing a 300 micron cut point without compromising its efficiency significantly. Installation of two Derrick high frequency screens, capable of a 310 micron cut point, is therefore recommended to replace the cyclone. As this replacement will also reduce the mill circulating load from over 200% to 65%, the tanks and pumps in that part of the circuit will not need upgrading.

The feed to the secondary mills is a 250 mm diameter gravity line with a 5-degree angle. This line will handle the additional flow; however, it will need to be carefully assessed given the coarser grind size.

The two parallel regrind circuits will operate simultaneously. The discharge tanks and pumps will be unchanged as the flow through each regrind mill does not increase.

The secondary classification circuit will require the installation of a second cyclone pack (one dedicated to each regrind mill).

The current process plant at Island Gold is composed of a two-stage crushing circuit followed by
a two-stage grinding circuit. The mill uses cyanide leaching and a carbon-in-pulp process to recover gold.

Modifications for increasing capacity to 2000 tpd include:

Pre-Leach Thickener Modifications
As part of the expansion, the thickener rake and rake drive unit should be inspected and refurbished during a scheduled shutdown during construction. Also, the thickener’s feed well will be inspected for potential modifications, and the underflow and overflow configuration will be modified.

The feed flow increases from 256 m3/h to 384 m3/h. The thickener’s feed launder is assumed to be insufficient at the increased flowrates and will be replaced as part of the expansion construction.

Feed well modifications will be required. These modifications are recommended to be undertaken with the assistance of the original thickener supplier. A high r ........