Trigg Mining delivers positive scoping study for Lake Throssell sulphate of potash project

Perth-based explorer Trigg Mining (ASX: TMG) has announced the completion of a scoping study on its flagship 100% owned Lake Throssell sulphate of potash (SOP) project in Western Australia’s eastern goldfields.

Delivery of the study follows the successful upgrade of a portion of the total drainable mineral resource to the indicated category in July and has led to the company approving the immediate commencement of a pre-feasibility study (PFS).

The Lake Throssell SOP project is proposed to comprise the harvesting of brine water from subterranean aquifers, evaporation ponds, a processing plant and supporting infrastructure to produce a naturally-forming, potassium-rich salt, SOP, which is used globally as a fertiliser and for other industrial purposes.

Highlights of the scoping study include an annual nameplate production target of 245,000 tonnes per annum of SOP over a 21-year life of mine, based on a total drainable mineral resource of 14.4 million tonnes at 4,665 milligrams per litre of potassium (or 10.4 kilograms per cubic metres of SOP).

The study estimates an initial capital cost of $378 million, including a $70 million contingency. The project is forecast to generate average earnings before interest, tax, depreciation and amortisation (EBITDA) of $97 million per annum at an SOP price of US$550 per tonne.

Lake Throssell has a net present value of $364 million with an internal rate of return of 18% and a payback period of 4.5 years.

Other estimates include a life of mine average cash operating cost of $341/t SOP and an all-in sustaining cost of $372/t SOP.

Potential ‘company maker’

Trigg managing director Keren Paterson said the scoping study outcomes strongly vindicate the company’s long-held belief that Lake Throssell is a potential “company maker – a high-quality, long-life asset which can transform Trigg into a modern, sustainable Australian SOP producer with a top 10 globally competitive project”.

“The key attributes of the project are clearly highlighted in this study – the scale and quality of the resource, its tier one location, proximity to infrastructure and ability to support a multi-decade operation which can also deliver a number of exceptional environmental and social governance (ESG) outcomes.”

“Apart from the social and economic benefits it will provide, the project utilises solar evaporation to produce a natural fertiliser essential for global food security,” she added.

Next steps

Trigg is now progressing to the next stage of the Lake Throssell project with a PFS, which is expected to be completed by early 2023. The company is targeting an investment decision for the project in mid to late 2025.

It will also continue environmental baseline surveys with environmental approvals being the next critical milestone on the project development schedule.

Resource definition work will continue in the first half of 2022 with the installation of about five test production bores installed along the strike of the palaeovalley. The aim of this work will be to obtain data needed to determine an ore reserve.