The Thunderbox gold mission consists of the Thunderbox, Rainbow and Otto Bore gold deposits in Western Australia.
The mission is developed as each an open-pit mine and an underground mine.
The Thunderbox deposit was found in 1999 and is without doubt one of the vital gold deposits found in Australia.
The mission was acquired by Saracen Mineral from Norilsk Nickel in 2014. First gold was poured in early 2016 whereas business manufacturing was achieved in April 2016. Saracen Mineral was acquired by Northern Star below a merger-of-equals settlement signed in October 2020.
Thunderbox gold mission location
The Thunderbox gold mission is a part of the Thunderbox operations (TBO), which additionally consists of the Kailis, Bannockburn and Waterloo tasks.
Thunderbox is located on the southern finish of the Yandal greenstone belt whereas TBO is positioned within the Yandal belt and the Agnew-Wiluna belt within the North Jap Goldfields. The Thunderbox open-pit mine and carbon-in-leach (CIL) gold remedy plant are positioned 45km south of Leinster.
Thunderbox mission geology and mineralisation
Thunderbox is a mesothermal lode gold deposit located in an space the place a number of main shear zones meet with the Perseverance Fault. The deposit incorporates three important mineralised zones, generally known as A, C, and D.
Mineralisation within the deposit is current within the type of closely distorted, silicified and carbonate-altered albite-quartz porphyry within the hanging wall of the 200m-wide shear zone. The mineralisation is especially restricted to the intrusive porphyry.
Reserves on the Thunderbox deposit
The Thunderbox deposit is estimated to comprise confirmed and possible ore reserves of 40.94 million tonnes (mt), grading 1.6gpt of gold, as of March 2024. The entire contained metallic is estimated at 2.14 million ounces.
Mining at Thunderbox gold mission
Mining operations on the Thunderbox gold mission commenced in July 2015. The first ore feeds come from the Thunderbox open-pit and underground operations. Supplementary feed is derived from the Otto Bore, Surprise and Orelia mining centres.
Thunderbox utilises cost-effective bulk strategies by each open pit and underground operations. The open-pit mining fleet entails the usage of a backhoe-configured excavator, supported by a fleet of rear dump vans.
The underground operation is a contemporary, mechanised, trackless mine that employs long-hole open-stoping strategies tailor-made to the width of the ore zones. Just lately, paste fill has been launched to boost ore restoration and keep stability within the mining areas.
Otto Bore is a small satellite tv for pc open pit operation positioned roughly 10km north of TBO and employs typical truck and shovel operations.
The Surprise underground mine is positioned roughly 25km south-east of the TBO processing centre. Mining commenced in November 2023 with operations performed through typical jumbo lateral improvement utilizing long-hole open-stoping strategies.
The Orelia (Bronzewing operation) is an open-pit mining operation undertaken utilizing a traditional truck and excavator. All ore from Orelia is trucked to the Thunderbox processing centre.
Processing at Thunderbox mission
The ore reserves from the mine bear remedy on the Thunderbox CIL cyanide leach plant with a gravity circuit.
The processing plant was saved on care and upkeep since 2007 and has been working at a nameplate capability of two.5 million tonnes every year (mtpa) since Might 2016. The processing facility was expanded from 2.9mtpa to 6mtpa in 2022.
The improve of the Thunderbox mill included enhancements to the standard crushing circuit and reclaim space, in addition to enhancements to the grinding and milling circuit, pebble crushing, leaching, elution, tailings administration, reagents, and related companies.
Website infrastructure at Thunderbox mission
Saracen acquired the prevailing infrastructure, together with a contemporary lodging camp, a gravel airstrip, a Goldfields Fuel pipeline spur and the CIL ore processing facility. Contract energy provide, water provide from borefield and telecommunication companies had been additionally a part of the acquisition.
The mine website is linked to Leinster through a 2km sealed freeway.
Saracen developed a powerhouse with seven gas-fired turbines and 4 dual-fuel models.
Contractors concerned
SRG World was awarded a $70m contract in March 2020 to offer drill and blast companies on the mine for 5 years.
Kalgoorlie Energy Techniques (KPS) was contracted to rewire the powerhouse whereas BLA Burgess undertook the re-installation of the SAG and ball mills.
Maca Interquip was contracted for plant refurbishment whereas SMS Rental (WA) received a contract for the provision and upkeep of run-of-mine (ROM) loaders.
Northern Star Sources (NST) awarded GR Engineering the contract for the design, procurement, development, and commissioning of the growth of the processing services at its Thunderbox operation.