Rainbow plans to produce the rare earths that are critical building blocks in the clean energy transition, namely NdPr, Dy and Tb. Used in permanent magnets for motors and turbines, these rare earth elements are fundamental to global decarbonisation. The Company is focused on producing these metals in an environmentally-responsible manner.
We are committed to integrating environmental considerations into strategic decision-making at the highest level of the business (i.e. Board and Sustainability Committee level) in order to create a responsible and sustainable supply of critical rare earths. We aim to achieve continuous improvement in environmental practices and performance and to minimise, or where possible avoid, negative impacts from our operations on the natural environment, including those relating to climate change, water usage, waste management and biodiversity.
Environmental management is a key element of Rainbow’s OHS system and is overseen by the Sustainability Committee. The Company complies with applicable environmental laws and regulations.
Generating rare earths from waste to power the green transition
The low-carbon technologies required to facilitate the green transition carry an intensive demand for minerals; accelerated by evolving emissions legislation and targets, rare earths demand is expected to be driven by growing electric vehicle production and offshore wind exploitation. For more information on rare earths, see Market.
Apart from delivering products that are vital to global efforts of decarbonisation, Phalaborwa has strong environmental credentials in terms of reducing legacy risks from the previous operations on site to an environmentally sensitive area.
Phalaborwa is founded on the principles of circularity via the extraction of value from ‘waste’ products. The operation will involve the processing of phosphogypsum stacks, which are the by-product of historic phosphoric acid production on the site, which ceased in 2014. This resource sits at surface, thereby eliminating the cost and risk of traditional mining projects.
Rainbow has the opportunity at Phalaborwa to clean up legacy environmental issues on site, the main one being acid water which has accumulated over the unlined gypsum stacks. The acid water will be neutralised and used as process water, with the remnant gypsum then deposited on new lined stacks according to International Finance Corporation (“IFC”) / Equator Principles. This gypsum is intended to be further on-sold as a clean and benign feed for the cement and other industries, leaving the site rehabilitated to its original state over time.
Unlocking value from historical waste
By processing of material from historical waste, we aim to make a positive environmental contribution by producing integral raw materials for the green revolution and removing environmental liabilities, to the greatest extent possible.
The phosphogypsum stacks at Phalaborwa are the result of 50-60 years of waste residue deposition from Sasol’s phosphoric acid production. Sasol still carries the majority of the liability for this waste, however by re-processing the material, we have the opportunity to neutralise acid water and redeposit benign gypsum, suitable for use in building and other industries, on a new stack, built according to IFC Performance Standards and Equator Principles.
The internationally recognised consultant KnightsPiesold currently manages the gypsum stacks and has an environmental plan in place. An Environmental and Social Impact Assessment (“ESIA”) is currently underway and is being conducted by consultants WSP in accordance with IFC Performance Standards.
As the rare earths at Phalaborwa are contained within existing stacks of waste gypsum residue, the project does not carry the environmental challenges often associated with extracting rare earths from the ground.
Furthermore, the intention to sell the benign gypsum by-product produced at the project is expected to see the phosphogypsum stacks at Phalaborwa eventually fully depleted, which would allow for a complete environmental rehabilitation of the site.
Responsible water management
There is circa 700,000m3 of acid water associated with the phosphogypsum stacks at Phalaborwa and Rainbow is investigating the optimal ways of treating and reusing this as part of our overall water management strategy.
Water neutralisation test work has confirmed the ability to treat the existing water from the stacks and reuse it in a closed circuit as plant process water. This not only reduces the substantial legacy issue of acid water from historic work (prior to the Company’s involvement) but will also reduce overall freshwater usage in the flowsheet. Any water discharged to the environment will be done so in line with regulations.
Key environmental considerations – energy use, radioactivity and reagents
With fewer expected processing steps, anticipated lower energy and reagent requirements than a traditional rare earths project, the production of concentrate at Phalaborwa is expected to have fewer negative environmental impacts.
Sulphuric acid, a key reagent for the Project, is produced as a waste stream at the copper operation next to Phalaborwa – by using this sulphuric acid, Rainbow has the opportunity to recycle a by-product, as well as reduce the carbon footprint which would be associated with reagent transportation, due to the proximity to the Project. Gakara does not use reagents in its trial processing circuit.
Very low levels of radioactivity have been confirmed within the gypsum extracted from Phalaborwa, significantly below the International Atomic Energy Agency (“IAEA”) guidelines, therefore exempting the Project from regulation pertaining to radioactivity. Most rare earth projects have higher levels which then require the producer to remove and store radioactivity which carries significant environmental (and cost) challenges.
The pilot plant at Gakara employs simple gravity processing to deliver a high-grade concentrate with low levels of radioactivity suitable for export, thereby producing one of the “greenest” rare earth concentrates in the world.
Task Force on Climate-Related Financial Disclosures (“TCFD”)
We are committed to embedding environmental considerations into Phalaborwa’s development and are therefore intent on putting the right foundations in place from the outset from which to build our sustainability strategy. Developing climate change-related strategies and commitments is a key element of this approach. Rainbow’s climate-related reporting will mature as we move through project development and construction and into production. We intend to publish a standalone disclosure report in line with the recommendations of the TCFD in due course.
In preparation for such a disclosure, we have published initial TCFD disclosures, which are presented according to the TCFD key themes and recommendations for the period 1 July 2022 to 30 June 2023.