Newmont’s Tanami Expansion 2 (TE2) in the Northern Territory – the largest mine expansion project in Australia – has seen some significant recent developments. The gold project, which is developing an extensive new materials handling system, including an underground crusher, conveyors and a 1.46 km-deep shaft hoisting system, is Newmont’s biggest capital expenditure project underway in Australia.
Over November 30/December 1, TE2 completed shaft development and concrete shaft lining down to 1,292 m below the surface. In addition, TE2 completed the installation of the ABB Koepe (friction) winder drum. At 6 m in diameter, it weighs a total of 40 t. In the next two weeks, the team will install its brake discs and brake assemblies before an 81 t 5.3 MW motor will be placed in position.
The production hoist has two 28.5 t skips; with one skip every 2.2 minute and 25 trips per hour while the personnel hoist has a 26 person capacity over two decks; and is capable of 3.2 trips or 84 persons per hour. The production winder is fully automated; with a full speed of 16 m/sec. It is also one of the few Safety Integrity Level (SIL) rated winders in the world. It is also regenerative with a battery energy storage system (BESS). The personnel winder is an ABB single drum winder having a 623 kW DC motor with gearbox and 3.6 m drums. The production skips will be able to handle 3.8 Mt/y including waste.
When complete, TE2 will be the deepest production shaft of any mine in Australia, and its 93 m headframe is one of the highest structures in the Territory. TE2 will transform Tanami into a state-of-the-art crush and hoist operation, and it will add another 150,000 to 200,000 gold ounces per year to production while at the same time reducing operating costs by ~30%. The 1,460 m deep shaft is the deepest raise bore shaft in Australia. The project includes an accommodation village, refrigeration & water treatment plants, plus concrete batch plant.
Underground TE2 has seen lateral development of 7,287 m. Vertical development has included an 8.5 m diameter by 20 m transfer silo and 8.5 m diameter by 50 m fine ore silo. The underground material handling system consists of a 3.8 Mt/y primary crusher, conveyors and transfer stations. Underground infrastructure includes a 100-person refuge chamber, pump station, dewatering dams and refuelling station.
On surface, the TE2 process plant upgrade will take plant capacity from 2.6 to 3.3 Mt/y. Additions include the new shaft headframe, winders, conveyances, skip unloading, transfer stations & conveyors; with new power, water, electrical and communications services. Surface facilities for TE2 that are completed include a power plant expansion, refrigeration plant, bulk air cooler, vent raise (VR8), water treatment plant, administration offices plus DBS Camp Stages 1 and 2, storage dome and batch plant. In progress and planned facilities include the process plant upgrade to increase current capacity to meet the increased 3.3 Mt/y throughput by increasing flow through the secondary ball mill which is in design. The headframe and winders are in progress while the waste stacker, tailings motor and pumping system upgrade are planned.
Lining of the upper shaft leg and mid shaft are complete; and lining is underway in the lower shaft leg. The project remains on track for commercial production in the second half of 2027. Total capital costs remain between A$1.7 billion and A$1.8 billion.
Looking at the wider Tanami operation, it has 855 employees and 1,420 contractors. It is primarily a fly-in fly-out operation with an over 40-year history of production with the first gold produced in 1983; Newmont acquired Tanami from Normandy in 2002. It includes one large underground mine at Dead Bullock Soak (DBS). Since 2012 Tanami has been under operational transformation and delivered a first mill expansion in 2017 then improved power efficiency with the Tanami Natural Gas project in 2019. Newmont has increased production by ~170% since the site transformation began in 2012. The current mine life beyond 2040; growth case includes inventory and exploration upside extending the life to 2047. Gold Reserves stand at 4.8 Moz with Resources of 5.2 Moz.
The current strategic focus is the safe commissioning of TE2 by H2 2027 along with optimising the ventilation, paste and mining sequence. The mine is also implementing new technology – including Caterpillar Minestar, plus new fleet management, collision avoidance and automation systems. Tanami is also securing long-term gas agreements with the Northern Territory with ongoing exploration at depth and other near-mine targets.
Cat Minestar fleet management systems in the Tanami control room
Tanami is one of Australia’s largest open stope mines. There are four mining areas at DBS: Auron, Callie, Federation and Liberator. The operation teams focus on mine development, mine services, paste fill, drill and blast and haulage. The head grade ranges between 4 and 8 g/t. There is a current underground development depth of over 1.7 km with TE2 set to solve the material movement constraint below 2 km. The mining fleet consists of 22 trucks, 10 loaders, five jumbos, three long hole drills, two raise bores and 150 additional support machines.
Regarding ventilation, significant heat is added to the system due to extreme surface temperatures in summer, with ambient rock temperatures of 60 degrees Celsius, plus thermal heat from mobile equipment and auto compression with high pressures underground. Ventilating the large underground mine requires significant amount of power (~8 MW of power for primary ventilation, ~35 MW of power for cooling and over 150 secondary fans in the mine).
The DBS open stoping is a well-established mining method, appropriate for the depth of the mine; this will be modified as the mine progresses deeper. DBS has relatively good ground conditions and uses several types of ground support determined on the conditions. At depth, dynamic ground support is used to manage the increasing ground stress and seismic events. DBS also has a comprehensive ground control management system to monitor ground conditions
Ore is transported via road train 44 km to the processing plant at the Granites. The mentioned first mill expansion in 2017 increased mill capacity to 2.6 Mt/y with TE2 expected to increase this to 3.3 Mt/y. Mill debottlenecking projects are critical to maintaining higher throughput (crushing circuit, tails pumping). Tanami has excellent mill recovery with ranges between 98-99%. Some 65-75% of the gold is recovered via gravity and 30% of tailings are recovered for backfilling stopes.
Launched in Q2 2024, the Minestar Fleet Management System replaced the previous manual dispatch system with real-time fleet tracking and data capture. An underground Wi-Fi network now tracks machine movements, delivering precise, real time shift data. It also supports a more seamless assignment system and personnel tracking, as well as integrated site communications with live data feeds to the control room. Minestar unlocks value through optimised fleet management, efficient resource scheduling and elevated operator performance as well as improvements through real-time asset health monitoring.
It also monitors equipment metrics and flags developing maintenance issues for preventative repairs before a breakdown occurs. Newmont says Minestar’s automatic, real time data capture is significantly outperforming the conventional manual dispatch system, leading to improved operational performance.
