Ammaroo will be an open-pit phosphate mining operation.
The project will be developed in two stages for a total mine life of 25 years.
The proven and probable phosphate reserves at the deposit are estimated to be 32.4Mt.

The Ammaroo phosphate project is a proposed open-cut phosphate mining project located in Northern Territory, Australia. It is one of the biggest identified phosphate deposits yet to be developed in Australia.

The project is fully owned by Verdant Minerals (VRM), formerly known as Rum Jungle Resources, which also owns the Karinga sulphate of potash project and the Dingo Hill silica project in the Northern Territory of Australia.

A feasibility study for the Ammaroo phosphate project was completed in May 2018, while the approval from Australia’s Northern Territory Environment Protection Authority (NTEPA) was received in October 2018.

Planned to be developed in two stages, the project is estimated to produce up to two million tonnes (Mt) of rock phosphate annually over an estimated mine life of 25 years.

The total capital investment for the project is estimated to be £316m ($426m). The stage one development is expected to incur £205m ($276m), while the stage two construction cost is estimated to be £111m ($150m).

Location and site details

The Ammaroo project area covers approximately 3,775ha in the Northern Territory of Australia, approximately 270km north-east of Alice Springs and approximately 200km south-east of Tennant Creek.

The project’s location will help to meet the domestic phosphate demand on Australia’s east coast via Adelaide and to export to the Asian Markets via the Port of Darwin.

Ammaroo phosphate reserves and production schedule

The Ammaroo phosphate project is estimated to hold a total of 32.4Mt phosphate reserves grading 18.2% phosphorus pentoxide (P2O5). It includes 11.8Mt of proven and 20.6Mt of probable reserves.

In the first stage one, the project is expected to produce 1Mtpa phosphate for the initial five years of operation. It will be increased to 2Mtpa in the next 20 years of operation in stage two.

Mining and processing

The conventional truck and shovel open-pit mining method will be employed as the shallow Ammaroo phosphate deposit is amenable for low-cost free digging operation. The open-pit will cover a total surface area of 1,500ha.

The extracted resources will undergo screening, crushing, grinding, and will be beneficiated to a 33% phosphorus pentoxide (P2O5) market standard rock concentrate through froth flotation at a nearby processing plant.

Infrastructure facilities for the Ammaroo phosphate project

Apart from a beneficiation plant onsite, the Ammaroo phosphate project will also have a surface tailings facility (TSF) covering approximately 90ha, a temporary construction camp for approximately 350 workers, a gas-fired power station to be built and operated by a third party.

The gas is proposed to be sourced through a new 120km low-pressure gas pipeline from the existing Amadeus gas pipeline.

The project also involves a 90km rail spur connecting the Adelaide to Darwin railway for the bulk haulage of phosphate products as well as to facilitate the supply of diesel and reagents by inbound trains.

Project financing

Verdant Minerals is expected to receive a £92m (A$160m) loan facility from Northern Australia Infrastructure Facility (NAIF), which is the lending facility of the Australia Commonwealth Government to finance projects via the governments of the Northern Territory, Queensland, and Western Australia.

Off-take agreements

Verdant Minerals entered into a non-binding memorandum of understanding (MoU) with Wilson International Trading for the off-take of up to 350,000 tonnes per annum (tpa) of phosphate rock concentrate from the Ammaroo project in March 2018.

A similar MoU for the off-take of 100,000tpa of concentrate from the project was signed with Ameropa Australia in May 2018.

Contractors involved

Worley Parsons was engaged for the engineering and plant and infrastructure design services, while Mining Plus provided mine planning services for the feasibility study of the Ammaroo phosphate project.

Corem provided metallurgical testwork services, while GHD provided environmental consulting services, and Magma Capital provided financial modelling and debt advisory services.