The Carosue Dam Operations (CDO) assets include the Carosue Dam Project (comprising the Karari and Whirling Dervish gold deposits), the Porphyry Project (consisting of the Porphyry, Million Dollar, Enterprise and Wallbrook gold deposits) and the Deep South Project (consisting of the Deep South, Safari Bore and Box Well (Moody’s Reward) gold deposits).

Gold mineralisation at Karari is hosted within extensive quartz vein breccia zones in an altered volcaniclastic metasandstone and tuff sequence. This sequence is offset by an anastomosing system of NE-SW and NW-SE trending shear zones and intruded by monzonite bodies post- mineralisation (ca. 2.6 Ga). The host sedimentary sequence dips moderately to the north. Gold mineralisation is strongly associated with sodic alteration (quartz+albite+carbonate) of the host rock that was subsequently overprinted by hematite alteration. High grade mineralisation is controlled by 60° east dipping shear zones. Mineralisation has continuity over 1,000 m along strike, 1,100 m down dip and 250 m across strike.

Mineralisation occurs at the intersection of Eliot Lode Shear and Monty North Shear. Occurs as quartz stockwork veining along contact between fine grained porphyry and underlying volcanic sandstone sequence, with strong and pervasive hematite alteration halo. Gold occurs mainly as blebs, intergrown within pyrite or as disseminations in the host units. Lodes comprise NW trending lensoidal to anastomosing mineralised zones of variable widths (between 5 to 40 m), which mostly dip to the east (50 to 60°) and plunge shallowly to the south. Lodes extend for >950 m along strike, 400 m down dip and up to 50 m width (when stacked together).

Mineralisation at Twin Peaks occurs in an overturned, turbiditic metasedimentary package located below the regional-scale Kilkenny-Yilgangi Fault, within an intensely fractured, east plunging alteration zone. The stratigraphy strikes northwest and dips 60 - 70° to the northeast. Gold distribution is characterised by a quartz-arsenopyrite breccia within a sericite-carbonate alteration envelope. Within 100 m of surface the deposit has an ellipsoid shape measuring approximately 90 m by 45 m, but becomes pipe-shaped below this depth and plunges southeast at around 50°. The deposit is open below 300 m.

The stratigraphy at Pinnacles is dominated by volcanic sandstones, black shales, mafic and ultramafic volcanics, and granites. Gold mineralisation is structurally controlled along the north-trending Pinnacles Shear and dips towards the west (80 to 85°), with a gentle southerly plunge. Gold is hosted within four southerly plunging shoots within the black shales with associated quartz veining and significant haematite-sulphide alteration. Mineralisation extends over 330 m strike, 70 m width and 180 below surface.

Mineralisation at Blue Manna is interpreted as a series of stacked parallel lodes associated with lithological / structural contacts between units in a dilated sandstone unit within a sandstone-siltstone package along the NNW trending Keith-Kilkenny fault zone. It is accompanied by silicification, quartz veining and minor sulphidation. The continuity of the mineralisation extends for 500 m along strike, 150 m in width and to 150 m surface.

The Atbara deposit is hosted within a volcanosedimentary package comprising intermediate felsic volcaniclastic sandstone, tuff and porphyry units intruded by various monzonitegranitic bodies. This package dips to the east at approximately 60°. The main host to known mineralisation is the Atbara monzonite, which is concordant to stratigraphy. Mineralisation comprises multiple lodes extending for some 800 m in length by 450 m in width and to 450 m depth.

The Porphyry deposit comprises a series of staked en echelon lenses (in part fault separated) within a quartz monzonite. Mineralisation is associated with intense shearing and confined to thin shear bands approximately 10 cm thick which feather out into multiple, thin low-grade bands. Structural controls on mineralisation are shallow (20-25°) eastdipping brittle shear zones, related to NNW trending regional faults. Strong hematite alteration is apparent. The largest lens measures 400 m in length by 150 m in width and dip 40° to the south. The lenses extend over a 1.4 km strike length and extends to 300 m below surface.

Gold mineralisation at Million Dollar comprises shallow dipping (30°) stacked en echelon quartz veins within a braided shear system in a syeno-monzonite granitoid unit. Secondary mineralisation occurs at the granitoid margins within strain shadows and cross-linking structures between the main lodes. Structural controls on mineralisation are shallow eastdipping, north-striking shear zones related to NNW trending regional faults. These shears are typically 1-10 m in width. Higher grades associated with albite-silica-hematite alteration along with shear parallel quartz-pyrite veining. Mineralisation extends over a 1.8 m strike length, 500 m width and to a depth of 250 m below surface.

At Wallbrook, a mineralised quartz vein stockwork has developed within and adjacent to a small syenogranitic intrusion within metabasalt. Two deposits have been historically mined at a small scale at Wallbrook: Redbrook and Eleven Bells. Redbrook mineralisation is associated with a quartz vein stockwork along the granitoid contact. Eleven Bells mineralisation comprises quartz veining in metabasalt at the northern contact of the granite. The deposits have strike lengths from 25 to 260 m and plunge extents and widths up to 330 m.

The Deep South deposit is located within the narrow, NNW trending Linden Domain, within metasedimentary and felsic volcaniclastic rocks and intercalated ultramafic and high magnesian basalts. Mineralisation occurs in two concordant lodes; the Butler and Scarlett lodes. The Butler lode lies in the hanging wall and is strongly silica-pyrrhotite-pyrite altered. The Scarlett lode lies within a fine-grained carbonate unit and is strongly weathered. Both lodes have over 500 m strike continuity and 400 m down dip. The Scarlett lode averages 5 m in width and the Butler lode 2 m in width. Both lodes strike NNW and dip steeply west.

Margarets is a structurally controlled deposit occurring within N-S trending shear/fault zones and hosted by deformed andesites. These structures dip steeply east and where mineralised, are accompanied by haematitic alteration and a series of NNW trending quartz stockwork vein arrays (which dip steeply west) and south-plunging pipelike bodies. The main lodes extend for 350 m along strike and high- grade shoots plunge for 40-80m. The down-plunge continuity of Margarets remains open at depth.

Mineralisation at Enterprise lies within a south-plunging (25°) synform at the intersection of a strongly deformed andesites within N-S trending shear / fault zones (steeply east-dipping) and a series of NNW trending quartz stockwork vein arrays (steeply west-dipping). This mineralised system forms south plunging pipelike bodies. Gold mineralisation is associated with hematite-carbonate-quartz-pyrite alteration. The deposit extends over a 900 m area to 200 m depth.

The Safari Bore deposit is located within the Pinjin Fault (a regional NNW-trending structure). It comprises a subvertical WSW-dipping, NNW striking package of intensely deformed and altered intermediate to mafic intrusive/extrusive rocks and sediments intruded by felsic porphyry. Mineralisation occurs in multiple structural and lithological settings as four discrete lodes (red, green, purple and Serengeti). All lodes are associated with quartzcarbonate-albite hydraulic breccia veins. Red Lode and Serengeti lie within and at the margins of a gently southerly plunging felsic porphyry. Green and Purple lodes are subvertical sheets oriented sub-parallel to foliation. The deposit extends over 1.3 km in length, 300 m in width and to below 280 m depth.

The Karari-Dervish and Deep South are the active underground mines.

Karari Underground has been operating for 5 years and has continually ramped up production and currently produces approximately 1.2Mtpa. Underground mechanised mining for development, ground support, and open stoping is utilised at Karari. Mining and geotechnical studies have determined open stoping (both transverse and longitudinal) with paste fill is appropriate for the deposit. Some stoping locations will utilise remnant rib and sill pillars for either geotechnical reasons and/or availability of paste fill. This mining method of open stoping and backfilling with paste fill is widely used throughout the Western Australian Goldfields and Australia.

Dervish Undergound mines the orebody via a longhole open stoping method from top down with the ore production ramped up to approximately 850kt per annum, and along with Karari forms ‘Carousue Dam Underground’ which provides the majority of the mill feed.

The current Dervish mine design allows for: some areas of the resource to remain in-situ, as either rib or sill pillars, plus some resource areas to achieve higher extraction rates via the backfilling of adjacent stopes with paste fill. The current Karari mine design allows for paste fill to be used throughout the mine design and therefore the overall extraction ratio of this portion of the mineral resources is approximately 96%. Some mining of remnant pillars has been included in the mine design. Standard underground infrastructure is currently operational; this includes a decline for access and truck haulage, ventilation fans, escape-way ladders, electrical reticulation, mine services (air and water), and mine dewatering infrastructure.

The mining method to be employed at the Karari South deposit is conventional open pit mining with a hydraulic excavator, dump truck fleet, and drill and blast activity. The class of excavator employed is similar to other open pit mining operation, providing a good operating dataset for production and productivity rate measurement and financial modelling.

The mining method to be employed at Monty’s Elliot’s will be conventional open pit with hydraulic excavator and dump truck fleet, and drill and blast activity. The class of excavator employed is similar to other mining operations, providing a good operating dataset for production and productivity rate measurement and financial modelling. The Reserve pit is designed for both deposits namely “Monty’s” and “Elliot’s”. Monty’s reserve pit is designed as a cutback to existing mined pit, whereas Elliot’s reserve pit will be mined from surface.

Mining of the Twin Peaks at this stage deposit will be dominantly by underground mining methods involving mechanised mining techniques.

Porphyry Open Pits include: Million Dollar, Enterprise, Porphyry and Wallbrook.

In early 2020, civil and infrastructure construction works commenced in the Porphyry mining area to support long-term open pit mining in the area.

Mining of the Porphyry deposit will be by Open pit and Underground mechanised mining for development, ground support, and production stoping is planned to be used at Porphyry. Mining and geotechnical studies determined two mining methods; 1) Jumbo Drift and Strip, and 2) Long hole open stoping with remnant in-situ pillars to be appropriate for the deposit. Both of these mining methods have been previously successfully applied at Porphyry.

The Million Dollar open pit is now is full operation. The mining method employed at Million Dollar is conventional open pit with hydraulic excavator and dump truck fleet, and drill and blast activity.

The mining method to be employed at Wallbrook will be conventional open pit with hydraulic excavator and dump truck fleet, and drill and blast activity. The Reserve pit includes two deposits namely “Eleven Bells” and “Redbrook”.

The Enterprise pit has been included in the Carosue Dam life of mine plan. The mining method to be employed at Enterprise will be conventional open pit with hydraulic excavator and dump truck fleet, and drill and blast activity.

The Safari Bore deposit has added into the Carosue Dam life of mine plan. The mining method to be employed at Safari Bore will be conventional open pit with hydraulic excavator and dump truck fleet, and drill and blast activity.

Deep South is an active underground operation with mechanised mining, ground support, and production stoping. Mining and geotechnical studies determined two mining methods; 1) open stoping with remnant pillars, and 2) Modified Avoca with rock-fill to be appropriate for the deposit. Open Stoping with remnant pillars has been successfully applied at Deep South, while Modified Avoca (using rock-fill) will be implemented within a localised area to increase the resource extraction ratio. A bottom up approach incorporating production down-holes has been designed. Similar methods are currently utilised at other underground mines at Carosue Dam Operations.

The Deep Well deposit is amenable to mining by open pit methods.

The Crimson Belle deposit is amenable to mining by open pit methods. There has not been any serious mining at Crimson Belle. There are reasonable grounds to assume that in the future this deposit will be mined by conventional open pit methods given the close proximity of the mineralisation to surface.

Extensive Open Pit mining has occurred at the Butcher well deposits.

Contractor:
Byrnecut operates the projects from a centralised operations base at Carosue Dam, the contract encompasses two mining centres – Carosue Dam, comprising the Karari and Whirling Dervish mines.

The Carosue Dam mines utilise emulsion explosives, with production charging being undertaken by Orica, using an MCU on a subcontract basis. Deep South is an ANFO operation.

The plant incorporates primary jaw crushing, secondary cone crushing, crushed ore product screening and storage in a crushed ore bin. Crushed ore is reclaimed from the bin via two belt feeders that feed to a milling circuit. This circuit has recently been upgraded from a single-stage SAG milling circuit, incorporating closed circuit pebble crushing, to now incorporate a secondary ball milling stage. This allows increased throughput, and finer grind size (higher gold recovery).

The Carosue Dam Operations (“CDO”) processing plant was constructed by JR Engineering in 2000 and commissioned in November of that year.

The process flowsheet is a conventional cyanide leach-style circuit typically used to process free milling gold ores. The plant incorporates primary jaw crushing, secondary cone crushing, crushed ore product screening and storage in a crushed ore bin. Crushed ore is reclaimed from the bin via two belt feeders that feed to a milling circuit. This circuit has recently been upgraded from a single-stage SAG milling circuit, incorporating closed circuit pebble crushing, to now incorporate a secondary ball milling stage. This allows increased throughput, and finer grind size (higher gold recovery).

Gold recovery occurs via gravity gold recovery and intensive leaching, and cyanidation of the gravity tailings, to extract gold from the ores. The CIL circuit comprises of one leach tank and eight carbon-in-leach and adsorption tanks. Loade ........