The Taca Taca project is an open-pit copper, molybdenum and gold mining project located in the Puna (Altiplano) region of Salta Province, Argentina. The project is fully owned by First Quantum Minerals.
Discovered in the late 1960s, the Taca Taca deposit was acquired by Lumina in August 2008, while First Quantum Minerals acquired Lumina in August 2014.
A preliminary economic assessment (PEA) was released in 2013 after which additional exploration activities were carried out at the site. The primary environmental and Social impact assessment (ESIA) was submitted to the Secretariat of Mining of the Salta Province in February 2019.
A technical report with updated mineral resource and reserves estimates was released by First Quantum in November 2020.
The project is expected to enter the construction phase after 2024. The total investment on the project is estimated to be £1.97bn ($2.63bn) while the mine life is estimated to be 32 years.
Project location and geology
The Taca Taca project is located in Argentina, approximately 230km west of the provincial capital city of Salta and approximately 55km east of the Chilean border.
The project and associated areas consist of 75 concessions with third party groups having 50% ownership on two of the mining concessions.
The Taca Taca copper-gold-molybdenum porphyry deposit lies within the Puna region of Argentina which comprises of a back-arc basin bound by high angle reverse faults. The area is dominated by a series of granitic-composition batholiths and dykes that intrude the crystalline and metasedimentary basement of the Puna that are overlain by the back-arc basin sediments and volcanics of the Miocene Age.
Mineralisation and reserves
The Taca Taca deposit occurs on a 50km-long Ordovician batholith as a porphyry copper-gold-molybdenum mineralisation. The primary mineralisation is hosted in phyllic-altered Ordovician granite and associated aplite. The mineralisation is divided into the upper leached zone, the supergene and hypogene mixed mineralisation zones.
The proven and probable mineral reserves at the Taca Taca project were estimated to be 1,758.5 million tonnes (Mt) grading 0.44% copper, 0.012% molybdenum, and 0.09g/t gold, and containing approximately 7.73Mt of copper, 2.13Mt of molybdenum, and five million ounces (Moz) of gold, as of October 2020.
The Taca Taca project will utilise the conventional open-pit method involving drill, blast, shovels and trucks operations. The near-surface material is expected to be mined through free-digging method, while the drill and blast methods will be employed as the mining depth increases.
The open-pit mining is planned to be carried out in 30m benches while the batter height is expected to be 15m.
The primary load and haul fleet is expected to comprise hydraulic excavators, 90t electric shovels supported by 360t haul trucks. The stockpile rehandling and waste clean-up will be handled by front end loaders as required.
The processing facilities for the project are designed for an initial throughput of 30 million tonnes per annum (Mtpa) which is expected to be ramped up to 60Mtpa from the year 8 onwards.
The run-of-the-mine (ROM) ore will undergo three-stage crushing followed by two-stage grinding in a semi-autogenous grinding (SAG) mill and a ball milling to reduce the size of approximately 80% of the ore materials to180μm.
The milled ore product will be introduced into a rougher flotation circuit to produce a rougher flotation concentrate which will be dewatered and reground in a high intensity grinding (HIG) mill to further reduce the size to 30μm.
The reground product will be re-diluted with water prior to passing through a cleaner flotation circuit. Copper and molybdenum concentrates will be separated from the bulk cleaner and the remaining copper concentrates will be dewatered, thickened and filtered before the transportation to off-site smelters.
The molybdenum concentrates will also be dewatered, thickened, filtration and dried, while the coarse gold recovery will be enhanced by gravity concentrators.
The Taca Taca project site is accessible by road from the city of Salta located approximately 230km to the east.
The power supply requirement for the project is expected to be received from a 345kV transmission line north of the project site from the Güemes generating station in Salta Province which is privately owned and operated by Termoandes.
The fresh water supply will be sourced from the borefields in the Siete Curvas basin. The project will also utilise the high salinity brine water from the adjacent Salar de Arizaro.
The 2013 preliminary economic assessment (PEA) of the Taca Taca project was prepared by Ausenco.