Dear Sir,

Nature Research journals recognise the importance of post-publication commentary on published research as essential to advancing scientific discourse.

It is therefore with great concern and in the spirit of scientific rigour that we wish to point out significant errors in the D. Đorđević et al. paper “The Influence of Exploration Activities of a Potential Lithium Mine on the Environment in Western Serbia,” published in Scientific Reports on 24 July 2024.

Đorđević et al. present a number of incorrect, inaccurate or incomplete facts or data, use references in a way that can be misleading as it misrepresents the content of these papers and, have presented conclusions without the rigorous application of accepted scientific methods to arrive at such conclusions.

We detail a few examples to support the above observations. These are not exhaustive, and further instances from the paper can be found in the appendix to this letter.

The paper presents a number of incorrect, inaccurate or incomplete facts/data, including but not limited to:

Two examples of factual errors, amongst several others, are the following:

The D. Đorđević et al. paper reports a project area between 2031 and 2431 ha. The published, planned project has a total area of 388 ha which includes both the processing facility and the Štavice dry tailings tailings area^[1]. Furthermore, the planned area of the project is on the public record^[1], and Rio Tinto has records of correspondence between itself and the authors where this information has been shared.
It is stated that the wet tailings facility is being located next to Korenita and Jadar rivers, which are prone to heavy flooding of the surrounding areas. This is incorrect. The proposed tailings facility is at Štavice^[2] and is outside the flood prone area^[3]. Furthermore, a dry stack and not wet tailings facility will be built. Again, this is part of the public record^[2].

The paper cites references that do not support the statements made:

For example, Đorđević et al. claim that: “the least environmentally damaging method of exploiting lithium is from brines, while exploitation from ore rocks has severe environmental consequences”. To support this claim they reference Liu, Agusdinata and Myint^[4] “Spatiotemporal patterns of lithium mining and environmental degradation in the Atacama Salt Flat, Chile”. However, the Liu et al. paper focuses solely on impacts in the Atacama of lithium extraction from brine and makes no reference at all to other mining methods.
A further example is the references cited to support the statement that: “Initial exploratory drillings entailed the claims from the local population regarding the observed significant negative effects of groundwater by-production on soil and water quality. Such concerns have been augmented by existing information on the negative impacts of lithium mining on water usage, biodiversity loss, and waste generation elsewhere“. The three references cited^{[5], [6], [7]} refer to problems associated with lithium extraction from brines or potential recovery of Li from saline water. No reference to hard rock mining for Lithium is made in any of these papers, which is a completely different extraction method.

It is not convincing that a rigorous scientific methodology has been followed:

There are no soil and water baseline data prior to exploration that would allow one to conclude that the exploration activity generated soil and water contamination above and beyond such baseline levels. Therefore, we do not know whether their measurements simply reflect the natural occurrence of these elements in the environment or whether they are due to another prior cause. Indeed, historical evidence from Serbian geologists dating from the 1990’s attest to elevated levels of Boron, Lithium and Arsenic in the natural environment^[8].
Sample collection and analyses also lack background information essential for drawing solid conclusions. For example, no duplicate soil samples were taken. These are essential to determine the measurement precision which varies with concentration (lower precision as the analysis approaches the detection limit). Further, there is no reference to the detection limits for the instruments.
The paper states that a single reference material (BCR701) will monitor bias at the concentration of the element for the certified reference material (CRM). There is no detail as to what concentrations the CRM is certified to. It is stated that the reference material was 'used for determination of accuracy and precision'. Reference materials are used to monitor accuracy (bias), not for precision, and the paper conflates the two. However, our gravest concern is that according to the European Commission’s Joint Research Centre – Certified Reference Materials Catalogue^[9] the BCR701 certified reference material is an analytical reference material for Cadmium, Chromium, Copper, Nickel, Lead and Zinc, and not Boron, Arsenic and Lithium which are the elements referred to in the paper.

Supplementary materials

Some of the supplementary materials supplied are either not used in the paper, or insufficiently detailed for scientific use. A number of soil and water samples are omitted from the body of the paper without any explanation (MOESMS3, MOESM4, and the water sample from the Korenita stream), while the limited information supplied about location, timing and sampling technique is not adequate for interpretation.

There is clearly an important need for contributions from both the Serbian and international scientific communities to the broader discourse on potential lithium extraction in the Jadar Valley. However, these contributions must be factually accurate and subjected to rigorous scrutiny to ensure the objectivity of such scientific debate.

Based on the examples above, we believe that the paper by D. Đorđević et al. must be significantly corrected or retracted, in accordance with the Nature.com Correction and Retraction policy.

Yours sincerely

Nigel Steward, PhD
Chief Scientist, Rio Tinto
(contact for all correspondence)

Professor Aleksandar Jovović, PhD
University of Belgrade
Faculty of Mechanical Engineering
Department of Process and Environmental Engineering
Lead of development for EIA Process plant and EIA Industrial Waste Landfill

Professor Aleksadar Cvjetić, PhD
University of Belgrade
Faculty of Mining and Geology
Department of Occupational Safety and Environmental Protection

Professor Nikola Lilić, PhD
University of Belgrade
Faculty of Mining and Geology
Department of Occupational Safety and Environmental Protection
Lead of development for EIA Mine

Appendix – Supplementary facts

The paper claims that 203 ha of forest and 317 ha of arable land would be destroyed by the project. The proposed project has the potential to affect 173.45 ha of arable land and 206.5 ha of forest^[1]
Reported Li₂CO₃ production (50,000 t/year), and B(OH)₃ production (248,000 t/year) are inaccurate. The projected production of lithium carbonate is 58,000 t per year and boric acid 286,000 t per year.
Previous significant events are not considered in assessing the potential cause for As, B or Li levels found in the region such as the 2014 dam failure at the former Stolice mine in Kostajnik near Krupanj^{[10], [11].}
The paper claims that the Jadar location near an agricultural area and inhabited area is very unique, neglecting to mention the Greenbushes mine in Australia, located next to the town of the same name, operating successfully in a densely forested environment alongside agricultural activities, especially viticulture.
Quote from the paper: “Would the mine be opened, these toxic waters from the depth around the ore body, under pressure of several bars, would come to surface area that is rich in surface- and shallow high-quality groundwater. It will certainly significantly pollute both as well as the surrounding soil.” – No scientific data, modelling or references were provided in the paper to support this claim.
A claim is made in the paper that the opening of the mine will be followed by increased problems related to tailing ponds. The proposed Jadar project is not utilising a tailings pond given that all of the processing waste will be transformed into dry stack filter cake^[12].
Selection of water sampling points: Failure to mention or consider that the catchment area for the Jelav bridge sampling point is quite extensive and includes a different water course which drains directly from the southern slopes of Cer Mountain along a valley defined by the Lešnica Fault Zone.
Bore holes water sampling correlation with Jadar River As, B and Li concentration: Omission of sampling date information as well as the highly variable flowrate of the Jadar River^[13] (112 l/s to 28465 l/s) does not allow one to conclude that that there is any direct impact of the potential water leakage on water Li, B or As content.

References

[1] Spatial plan for the special purpose area for realization of jadarite exploitation and processing "Jadar" project (Official Gazette of the Republic of Serbia, no. 26/2020) (SPSPA)

[2] Environmental Impact Assessment Study for the Industrial Waste Landfill of Jadar Project in compliance with the regulations of the Republic of Serbia, Chapter 2, June 2023.

[3] Environmental Impact Assessment (EIA) Study of the project for underground exploitation of the lithium and boron deposit of Jadar, beneficiation plant and disposal of waste material resulting from the mining works, Chapter 6, July 2024.

[4] Liu, W., Agusdinata, D. B. & Myint, S. W. Spatiotemporal patterns of lithium mining and environmental degradation in the Atacama Salt Flat, Chile. Int. J. Appl. Earth Obs. Geoinf. 80, 145–156 (2019).

[5] Baspineiro, C. F., Franco, J. & Flexer, V. Potential water recovery during lithium mining from high salinity brines. Sci. Total Environ. 720, 137523 (2020).

[6] Flexer, V., Baspineiro, C. F. & Galli, C. I. Lithium recovery from brines: A vital raw material for green energies with a potential environmental impact in its mining and processing. Sci. Total Environ. 639, 1188–1204 (2018).

[7] Babidge, S., Kalazich, F., Prieto, M. & Yager, K. ‘That’s the problem with that lake; it changes sides’: Mapping extraction and ecological exhaustion in the Atacama. J. Polit. Ecol. 26(1), 738–760 (2019).

[8] J.Obradovic, N.Vasic, M.Kasanin-Grubin, N.Grubin, “Neogene lacustrine sediments and authigenic minerals geochemical characteristics”, Ann.Geol.Penins.Balk. 63 (1999), 135-154.

[9] BCR-701 LAKE SEDIMENT (trace elements) - Certified Reference Materials catalogue of the JRC (europa.eu)

[10] Izvestaj-projekta-Usluge-ispitivanja-stepena-degradacije-zemljista-usled-izlivanja-jalovista-Stolice-2018..pdf (ekologija.gov.rs)

[11] Ranđelović, D., Mutić, J., Marjanović, P. et al. Geochemical distribution of selected elements in flotation tailings and soils/sediments from the dam spill at the abandoned antimony mine Stolice, Serbia. Environ Sci Pollut Res 27, 6253–6268 (2020). doi.org

[12] Draft Environmental Impact Assessment Study for the Industrial Waste Landfill of Jadar Project in compliance with the regulations of the Republic of Serbia, June 2023.

[13] Draft Environmental Impact Assessment (EIA) Study of the project for underground exploitation of the lithium and boron deposit of Jadar, beneficiation plant and disposal of waste material resulting from the mining works, July 2024.