The Pine Point deposits are carbonate-hosted lead-zinc sulphide deposits with aspects of Mississippi Valley-Type (“MVT”). MVT deposits and a broader class of deposits called “sediment-hosted Pb-Zn” deposits (Leach et al., 2010).

Mineralization is hosted in three distinct deposit types:

1. Prismatic Deposits–Prismatic deposits demonstrate considerable vertical continuity but with limited lateral extent and are discordant. Mineralization is coarse to medium grained. These deposit types are further divided in to normal and abnormal prismatic deposits based on their relative stratigraphic position in the sequence. They contributed greatly to the Pine Point historical production as they contained very high-grade base metal grades and thicknesses.

2. Tabular Deposits–Laterally continuous, semi-concordant mineralized zones mostly restricted to a specific carbonate horizon.

3. N204 Deposit–N204 mineralization consists of fine crystalline mineralization deposited within the porosity ofstrati-bound layersbelow the mainsequence known as the B-spongy horizon where intense dissolution resulted in the development of a fine dolomite breccia. This type of deposit has to date only been identified at N204.

Prismatic Deposits
Prismatic deposits are generally high-grade and can contain up to 50% combined Pb-Zn, depending on the amount of sulphide mineralization present. These deposits are vertically continuous for up to 60m, and laterally restricted, generally 15-50m, but can be up to 140m wide. Metal zonation is present with a galena-rich core (Pb/Pb+Zn >0.3) enveloped by a more sphalerite-rich outer zone.

Prismatic deposits generally initiate at the Pine Point/Sulphur Point Formation facies transition and extend upwards through a dolomitized stratigraphic section, including upper sequences such as the Slave Point Formation. Abnormal prismatic deposits generally initiate within the lower stratigraphic sequences and extend upward.

These types of deposit generally contain blocks of overlying and adjacent stratigraphicmaterial. Such blocks can exhibit angular and dissolution textures. Cavities and vugs are common and abundant internal sediment accumulations are observed to fill earlier open spaces. These sediments are the residues of intense hydrothermal dissolution consisting of insoluble carbonaceous debris, argillite components, and sulphide material. It is believed that these sediments are remnants of the intense hydrothermal dissolution process associated with sulphide emplacement.

Tabular Deposits
Tabular deposits develop in distinct biomicrite facies carbonate sequencesin the lower Sulphur Point Formation.They are laterally continuous,following the general carbonate reef trend. They most likely followingthe increased porosity and permeability generated by hydrothermal fluid flow along distinct ‘channels’ or fluid pathways in suitable carbonate sequences. Other suitable host lithologies,e.g. the ‘B-Spongy’,are potential exploration targets.

Tabular deposits are vertically restricted relative to Prismatic Deposits and are generally zinc-rich (Pb/Pb+Zn) <0.2 with local lead-enrichment. They are lower-grade relative to prismatic deposits due to less massive and sporadic sulphide development. Zinc and lead grades decrease outwards from the core of hydrothermal fluid pathways (channels) and distally from interpreted local ‘feeder’ structures.

N204 Deposit
A related type of mineralization is found at N204 where tabular-like mineralization occurs in a lower part of the barrier reef stratigraphy in a horizon named the “B-spongy horizon” (Cominco Ltd. terminology). Here, precipitation of fine-crystalline dolomite resulted in the preferred dissolution of macro fossil components resulting in the development of a distinct moldic porosity. Mineralization at the N204 deposit is wholly confined to this dissolution horizon.

Mineralization
Mineralization at Pine Point is relatively simple, consisting of zinc, lead and iron sulphides occurring ina dolomitized, carbonate barrier reef complex. Sulphides consist of sphalerite and galena with subordinate marcasite and pyrite. Mineralization occurs as both openspace fillings and replacement of dolomite. The following types are documented:

1. Fine replacive sphalerite. This style of mineralization is common and present in tabular deposit typesand adjacent to more pervasive mineralization. It varies from massive to disseminated replacement sphalerite. The more massive replacement mineralization allows for the development of discrete banded colloform sphalerite masses.
2. Colloform sphalerite. Colloform mineralization develops with increased dissolution of the host carbonates with marginal replacement disseminations and fine filaments. The colloform mineralization is extensive at the core of tabular deposits. Well-developed colloform sphalerite decreases away from the core of the linear tabular depositsand is also present in the prismatic deposits.
3. Finely to coarsely-crystalline, replacive and openspace filling sphalerite mineralization. Sphalerite crystals up to 12mm are recorded in clean dolomitized biomicrites. There are limited and local amounts of associated marcasite.
4. Finely to coarsely-crystalline galena. Galena crystals typically define the last paragenetic stage of the depositional process and can be locally concentrated in galena-rich areas. Typically,however, galena is present in subordinate amounts compared to sphalerite.
5. Massive sulphides. Prismatic mineralization is generally massive, consisting of 100% carbonate-replacement sulphideswith a complete grain size spectrum from microscopic to mega crystalline sphalerite and galena mineralization. Multiple fluid phases allow for re-dissolution/precipitation and the generation of internal ‘openspace’ colloform mineralization, often spectacular and unique to the Pine Point District.Complex sulphide mineralization.
6. Complex sulphide mineralization in Prismatic Deposits also consists of massive sulphide replacing polymictic carbonates consisting of multiple ‘fallen’ or collapsed blocks from the overlying strata of the upper sequence carbonates, e.g.,large blocks consisting of Slave Point Formation and indeed the replacement of internal dissolution sediments developed during the dynamic formation of the chimney-like, vertically elongate massive sulphide deposits,which define typical Prismatic Deposits. There are local galena-rich zones, typically massive to coarsely-crystalline. 7. Heterogenous massive sulphides. Predominantly sphalerite-rich massive sulphides exhibiting characteristics of both replacive massive sphalerite but with a later more coarse-crystalline andslightly higher temperature sphalerite phase overgrowth. This appears to occur in several small prismatic deposits in the eastern portion of the Main Trend.
8. High temperature sulphides. Higher temperature, finely-crystalline, crypto-colloform ‘black’ sphalerite mineralization is typical of some North Zone prismatic deposits. This style is best developed in internal grey carbonate sediment with a ‘veines bleues’ dolomite association.N204 type mineralization.
9. The N204 mineralization is fine-grained, sphalerite dominated mineralization consisting of fine-replacive and minor fine to medium open space sphalerite crystals within moldic porosity.

Open-pit Mining
Most of the deposits are mined as open-pits with truck and shovel. The mine life span is 10 years. It is assumed that overburden material will not require drilling and blasting. The hauling of rock material and overburden will be performed by an average of fifteen to twenty 100t class-trucks. The loading of waste rock material will be handled by three 12m3bucket capacity hydraulic shovels. In addition, four 7m3bucket capacity hydraulic excavators will be used in the overburden and mineralized material for more selectivity.

Forty-seven deposits from four zones(East Mill, Central, North, and N204) are mined as open-pits considering the deposit’s size, shape, orientation, and proximity to the surface as well as economic parameters. Drilling, blasting, loading, and hauling are used to mine the open-pit mineralized material to meet the mine production schedule.

Underground Mining
The underground deposits are mechanized ramp access deposits that will use longhole stoping and room and pillar mining methods. The underground mine production rate starts in the West Zone at an average of 2,500t/day in Year 3 and ramps up to an average of 4,000 t/day from Years 4 to 6. After Year 6, the mineralized material from underground mining comes mainly from the Central Zone with an average productivity of around 1,500 t/day until Year 9. The overall underground mine life is expected to be approximately six years of production. All underground mining activities are carried out by contractor teams.

The deposits that are planned to be mined from underground are located in two zones: the West Zone (W1 Area) and the Central Zone (C1 Area). Longhole stoping was chosen for prismatic bodies while room and pillar method is conducted for tabular deposits. The West Zone contains mainly prismatic deposits that are more vertically continuous and therefore the main mining method is the longhole stope method. Room and pillar is used in the edges of the mineralized zonesfor the W1 Area and in C1 Area where only tabular deposits are identified. In the proposed mine plan, and for both zones combined, the longhole method provides 71% of the total tonnage, development will provide approximately 8%, and the room-and-pillar method will account for 21%.

In order to reach the productivity objectives, the average LOM ramp advance is 1,800 m/year for single-face excavations, and 3,600 m/year when multi-face excavations are available. For the longhole method in the West Zone, sublevels are developed at 25 m vertical intervals. Each level or sublevel is accessed using crosscuts (5 m x 5 m) from the main ramp to allow effective loading of haulage trucks. For the room and pillar method (West Zone and Central Zone), development is mainly done in the mineralized material. In general, stope accesses will have a dimension of 5 m x 5m, the same dimensions as the main ramp to allow free movement of equipment throughout the mine. The mineralized material and wasterock are hauled by LHDs from the production area to either a re-muck or loading bay excavated close to the main ramp. The mineralized material will then be loaded in 45t trucks and hauled directly to surface. For the West Zone, the haul trucks that will transport mineralized material to the concentratorare loaded at the portal and will take Highway 5to cross the Buffalo Riverand then continue on Highway 6 towardsthe nearest haul road to limit the distance used on the highway. For the C1 Area, 45t articulated trucks will transport the mineralized material.

Crushing and Mineral Sorting Circuit
The crushing circuit is designed to be fed 4.1Mt of mineralized material per year. The primary crushing circuit is composed of a vibrating grizzly feeder followed by a 160kW jaw crusher. The crusher reduces the feedsize from a maximum of 500mm to a P80of approximately 90 mm with a 105mm closed side setting. The crushed material is transported to the crushed mineralized material bin in the secondary crushing area via a conveyor.

Primary crushed material will be further crushed by a secondary cone crusher(600kW)at a 50mm closed side setting and the discharge will be fed to a classification screen to separate the fine material (-10mm). The fine material will be transferred directly to the fine mineralized material bin. The screen oversize is transferred to a secondary classification screen.

The secondary screen undersize, sized between 50mm and 10mm, will be sent to the mineral sorting circuit consisting of seven parallel mineral sorters at a design rate of 438tph. The mineral sorting will be done by using X-ray sensing technology. Each sorter is equipped with an air injection system that will eject the detected denser mineralized particles to the concentrate belt. The air for the injection system will be provided by 300kW air compressors dedicated to each mineral sorter. The mineral sorting concentrate mass pull is designed for 46%. The concentrate will be conveyed to a tertiary cone crusher (600kW) to be crushed under 10mmat a 13mm closed side setting. The tertiary crusher discharge will be transferred to the primary classification screen to close the circuit. Crushed mineral sorting concentrate is combined with the unsorted fines in the fine mineralized material bin to be conveyed to the grinding circuit.The mineral sorting rejects will be conveyed and stockpiled prior to being transferred by truck for disposal in selected areas near the open-pit operations.

Grinding Circuit
The mineral sorted material is ground in a ball mill, Ø4.88 m x 5.80 m (16’diameterx 19’length) F/F with 3,000hp motor installed,to a P80 of 100µm,which operates in closed circuit with a cyclone cluster. The production rate is designed to be 316 tph with 92% availability over 24-hr operation. The product fineness of the grinding circuit is monitored by an on-line particle size analyzer receiving a sample of the cyclone overflow slurry. Zinc sulphate (ZnSO4) will be added into cyclone underflow. Cyclone overflow will flow by gravity to the lead flotation circuit.

Recovery Methods
The processing plant will consist of the following unit operations:
- Primary jaw crushing;
- Secondary and tertiary crushing and mineral sorting;
- Fine mineralized materialstorage and handling;
- Ball mill grinding in a closed circuit with hydrocyclone classification;
- Lead flotation cells including rougher and two cleaning stages;
- Zinc flotation cells including rougher and two cleaning stages;
- Concentrate dewatering (zinc and lead concentrates);
- Flotation tailings thickening and pumping;
- Fresh and reclaim water supply;
- Reagent preparation and distribution.

Two types of final concentrates will be produced: a zinc concentrate and a lead concentrate.

Flotation
The cyclone overflow slurry will feed the conditioning tanks ahead of the lead flotation circuit. The lead flotation circuit will consist of one row of rougher cells and two rows of cleaner cells. The rougher stage will ........