Uranium deposits and prospects on the Hidden Bay property are of the unconformity type. Three deposits for which National Instrument (“N.I.”) 43-101 resources have been estimated occur on the Hidden Bay property: Horseshoe, Raven and West Bear. The Horseshoe and Raven deposits are located in north central portions of the Hidden Bay property. Mineralization at the Horseshoe and Raven deposits comprises shallow dipping zones of hematization with disseminated and veinlet pitchblende-boltwoodite-uranophane that is hosted by folded arkosic quartzite gneiss of the Hidden Bay Assemblage. Mineralization comprises a combination of disseminated pitchblende-chloritehematite, and narrower, higher grade nodular and veinlet pitchblende in hematite-clay alteration.

Mineralization at the Horseshoe and Raven deposits is entirely hosted by folded arkosic quartzite, quartzite and calc-arkosic gneisses of the Hidden Bay Assemblage and occurs at depths ranging from a few tens of m up to 460 m below surface. The mineralization is locally open at depth. The Athabasca sandstone is eroded from and absent in the area of the deposits, but local sandstone outliers that occur to the southeast of Hidden Bay and sub-Athabasca paleoweathering that is preserved in the near surface in some nearby drill holes suggest that the current surface is just below the elevation of the original sub-Athabasca unconformity in the deposit area, prior to its erosion.

The West Bear deposit, located in the southernmost part of the Hidden Bay property, is a classic unconformity-hosted uranium deposit which is developed under shallow Athabasca sandstone cover above a conductive graphitic gneiss unit. The deposit occurs along a conductive, graphite-bearing gneiss unit where it intersects the overlying Athabasca sandstone along the southern margins of the Dwyer Dome.

Mineralization at West Bear consists of sooty black pitchblende found as disseminations, blebs, and replacement of host rock minerals in both the sandstone and basement rocks. Minor yellow secondary uranium minerals such as uranophane and other gummite minerals are observed as disseminations and blebs in selected drill holes. Higher-grade holes contain intervals of semimassive pitchblende up to three metres in core length. Pitchblende, sulphides and sulpharsenides of Fe, Ni and Co and Pb (including pyrite, galena, niccolite, gersdorffite, cobaltite, rammelsbergite, and chalcopyrite) are the dominant metallic minerals in the mineralized zone (Fischer, 1981).

Sulphides are paragenetically early, followed by sulpharsenides, arsenides and pitchblende. Nickelcobalt-arsenic mineralization associated with the sooty pitchblende mineralization is most highly concentrated in eastern portions of the deposit, particularly in lowermost portions of the mineralized zone beneath the unconformity. In these areas, grades range up to 4% nickel. Lemaitre (2006) obtained typical average grades throughout the deposit of 0.34% Ni, 0.11% Co and 0.50% As. Anomalous Ni-Co-As mineralization also occurs in basement graphitic gneiss to the east-southeast of the deposit.

The preliminary mining investigation revealed that the Horseshoe deposit would be amenable to underground mining methods and the Raven deposit suitable for open pit (“OP”) mining. Raven also has the potential to support an underground (“UG”) operation, under the open pit, but it would need higher than the Case A U3O8 price of US$60/lb to be economic.

The choice of mining method was determined after taking into consideration all of the known contextual factors of the Horseshoe deposit. The main factors for determining an appropriate mining method for the Horseshoe deposit were: the irregular geometry of the mineralization with varying thicknesses and a 25° average dip angle, that makes the caving and sub-level open stoping mining methods unsuitable for the deposit.

Three mining methods were initially proposed to be appropriate based on the mineral deposit size, geometry and preliminary geotechnical assessment:
• Cut and Fill (“C&F”) mining method to be used where the mineral deposit thickness and dip would not allow taking more than one cut at the same elevation;
• Drift and Fill (“D&F”) mining method to be used for the wider portion of the mineral deposit which require more than one cut at the same elevation and where the grades of mineralized material would require a higher extraction rate;
• Room and Pillar (“R&P”) mining method would be used for low grade mineralization, where D&F mining would be uneconomic.

90% of total mineralized material would be mined by C&F and D&F methods and 10% - by R&P.

Considering the value of the mineralized material and mining cost, which are about 35% of total onsite costs, it would be more cost effective to increase mining extraction by using more expensive D&F method with cemented backfill for most of the deposit.

The D&F method is used in mineral deposits that are irregular in shape and have relatively high values as almost 100% of the mineralized material may be extracted. D&F mining has proved to be most useful in the extraction of areas that are not thick enough for efficient long hole stoping.

D&F is a development-style mining method in which parallel drifts are mined in a primary secondary sequence. After the primary drift is mined, it is backfilled with cemented fill so that a drift may be mined alongside the backfilled drift exposing stable fill walls due to the cement content of the fill. Using primary-secondary stoping sequence would reduce the cement consumption as secondary stopes would require less cement or no cement at all. Various layouts may be adopted along the same theme.

An average stope size of 5.0 m wide and 4.5 m high was assumed for mining productivities and cost estimation in this study.

The R&P mining method is an open stoping method that utilizes un-mined rock as pillars to support a series of rooms or small stopes around the pillars. The method normally is designed with pillars in a checkerboard pattern. The location of the pillars can be under survey control or done in a more random manner depending on the geotechnical requirements. The method is selective and zones of low grade can be left as pillars. Pillars can sometimes be mined on retreat to help improve the overall mining extraction.

The R&P method is normally quite productive, very flexible, and requires minimal access development before production starts.

An average stope size of 7.0 m by 7.0 m with pillar size of 5.0 m by 5.0 m was assumed for mining extraction, productivities and cost estimation.

The Hidden Bay deposits of Horseshoe and Raven are proposed to be developed both as an open pit (“OP”) and underground methods (“UG”). Mining of the Horseshoe and Raven deposits is proposed to produce a total of 2.49 Mt of mill feed and 15.0 Mt of waste over a 7-year mine operating life. Approximately 2.10 Mt of mill feed is planned to be produced from UG mining of the Horseshoe deposit, with 0.39 Mt being produced from OP mining of the Raven deposit. The mill feed is planned to be trucked to Cameco’s Rabbit Lake Facility for processing. It is assumed that a toll treatment agreement could be reached with Cameco, the owner of the Rabbit Lake plant, which would allow Hidden Bay mineralization to be processed at an average rate of 1,000 tpd. It is also assumed that the Rabbit Lake facility would provide toll tailings deposition for the Hidden Bay ROM material.

Ten primary circuits are used to produce yellowcake at the Rabbit Lake mill:
1. receiving;
2. grinding;
3. leaching;
4. counter-current decantation;
5. clarification;
6. solvent extraction;
7. gypsum precipitation;
8. uranium precipitation;
9. product drying and packaging; and
10. neutralization circuit.