In the last decade, lithium has become an object of desire of major economies and manufacturers of batteries and electric vehicles across the world, particularly in the context of the energy transition (World Bank, 2020; IEA, 2022; EC, 2023; USGS, 2023). Chile is currently the second largest lithium world producer—surpassed only by Australia—and it has the largest exploitable reserves of this mineral (USGS, 2023). Unlike in Australia, which produces lithium mainly from pegmatite rock, in Chile, it is obtained from the extraction and evaporation of mineralized groundwaters—also referred to as brines—from the aquifers of the Andean salt flats (or “salares”). Brines are pumped with extraction wells from saline aquifers and subsequently diverted to a system of evaporation ponds where lithium salts are concentrated through solar evaporation for 9–14 months (Flexer et al., 2018; Bustos-Gallardo et al., 2021). The amounts of brines required to produce one ton of lithium vary from one salt flat to another (and even within them) depending on the concentration of lithium minerals dissolved and the efficiency of the process used (Flexer et al., 2018). As part of this process, freshwater is also abstracted and used in smaller quantities as input for industrial activities, such as removing mineral salts.

Lithium extraction in Chile is currently carried out only in the Atacama salt flat. In 2020 new mining projects were approved in the Salar of Maricunga. In addition, several projects are in the preliminary stages of prospecting or exploration in 28 salt flats and saline lagoons in the country. Salt flats are fragile ecosystems characterized by unique biodiversity, including birds in the conservation category, such as flamingos, and benthonic microorganisms fundamental to the tropic chains. In these environments, aquifers of varying salinity are hydrodynamically interrelated, sustaining systems of lagoons, meadows and peatlands (high Andean wetlands), some of which have been recognized as national parks, reserves and Ramsar sites (Dorador et al., 2009, 2018; Thiel et al., 2010; Cubillos et al., 2019; Marazuela et al., 2019). In these terms, the salt flats constitute integrated salt flat-wetland ecosystems. Many salt flats are part of the ancestral territories of indigenous communities, such as the Atacameño/Lickanantay in the Salar de Atacama or the Colla in the Salar de Maricunga (OPSAL, 2021). The salt flats have also been fundamental for developing indigenous communities' traditional agricultural and transhumant grazing activities (Castro et al., 2004; Llagostera, 2004; Yáñez and Molina, 2011; Min. Minería, 2015; Prieto, 2015, 2016).¹

A growing body of literature analyzes the historical development, the socioeconomic impacts, the water and energy injustices and inequalities linked to lithium mining in the Chilean salt flats. Some of these works argue that mining operations produce environmental degradation in terms of decreased vegetation cover, decreases in the population of endemic fauna such as flamingos, increased temperature in local climate and drier conditions (Gajardo and Redón, 2019; Liu et al., 2019; Gutiérrez et al., 2022). They also analyze the challenges faced by local communities, which on the one hand, receive substantial direct or indirect economic benefits from mining companies, but on the other hand, have to live in a profoundly changed environment and face increasingly uncertain water and climate conditions (Babidge, 2013, 2016, 2019; Gundermann and Göbel, 2018; Babidge et al., 2019; Liu and Agusdinata, 2020; Lorca et al., 2022). Scholars have also discussed the material, institutional and discursive processes supporting lithium-brine mining and its continuous expansion including forms of green extractivism (Barandiarán, 2019; Bustos-Gallardo et al., 2021; Jerez et al., 2021; Forget and Bos, 2022; Voskoboynik and Andreucci, 2022).

Several authors note that the expansion of lithium extraction is underpinned by an understanding of mineralized groundwaters as minerals, or better, as mining resources (Babidge et al., 2019; Bustos-Gallardo et al., 2021; Jerez et al., 2021; Blair et al., 2022; Hernandez and Newell, 2022). Such interpretation has been historically supported by mining companies and the Chilean State—although with some nuances across different State institutions. Others, including indigenous groups and part of the scientific community, argue that brine is a type of water and therefore point out that lithium mining in salt flats is nothing more than water mining (Babidge et al., 2019; Garcés and Álvarez, 2020; Ejeian et al., 2021; Jerez et al., 2021). The brine-water nexus has been analyzed from a diversity of perspectives among others molecular analysis (Ejeian et al., 2021), critical resource geography (Bustos-Gallardo et al., 2021), political ecology (Jerez et al., 2021) and hydrogeology and geochemistry (Marazuela et al., 2019; Munk et al., 2021). This article contributes to the above scholarship by providing a critical legal geography perspective.² To this end, we analyze by whom and on what grounds specific legal definitions and interpretation of mineralized groundwater are articulated and how they (might) influence the regulation of mining of lithium and other minerals in salt flats.

For our analysis, we draw from recent work at the intersection between hydrosocial research and critical legal geography. This emerging scholarship sets out to understand in detail how laws, decrees, legal institutions, meanings and practices play an active role in defining and reconfiguring water(s) and their governance (Jepson, 2012; Cantor, 2016; Campero and Harris, 2019; Cantor et al., 2020). We extend the application of such an approach to lithium mining showing how—as for the case of desalination discussed by Campero and Harris (2019)—the existence of legal loopholes and undefined techno-legal frameworks has been used by powerful actors—mining companies—to push forward an interpretation on mineralized groundwaters as mineral resources that underpin an ongoing hydrogeographic reconfiguration.

We also examine the legal basis and potentials in fostering more just and sustainable governance of salt flats (and lithium mining) of two alternative understandings of water/brines, namely brine as hybrid mineral/water and brine as a type of water. Our analysis speaks directly to debates on water justice as it shows how legal frameworks are far from neutral tools but embed particular understandings and ways of knowing of water-society relations, while excluding others (Zwarteveen and Boelens, 2014). The paper is organized as follows: in the next section we introduce the analytical framework guiding our research, namely hydrosocial analysis and legal geography approaches. Subsequently, we describe the research methods and the case studies. We then outline the legal foundations on which the current prevailing interpretation of mineralized groundwater is based and how it has been defended and operationalized within the environmental impact assessment processes of currently approved projects—including contestations. We also explore emerging regulatory alternatives and how they consider the hydrogeological complexity of salt flats and discuss how these might contribute to safeguarding the socioecological balances and functions of salt flats. We conclude with a summary of our argument and a reflection on the implications of our analysis beyond the case of Chile.

In an often-quoted book, Jamie Linton asks “What is water?” (Linton, 2010). In the text, he goes on to explain that how water is defined and by whom largely shapes how water-related problems are addressed and, relatedly, which solutions are found. In this and other works, Linton traces the emergence of the so-called modern water paradigm, which is a tendency to understand water as essentially one and manage it out of its geographical, historical, and sociocultural contexts using uniform measures and rules (Linton, 2010, 2022; Boelens, 2014; Budds et al., 2014; Linton and Budds, 2014). Linton's work is a key contribution in hydrosocial research, a growing field of study largely inspired by political ecology to underscores the geographical and historical process through which water and society make and remake each other over time and space (Linton and Budds, 2014, p. 170). The hydrosocial approach has been used to make visible water injustices—the processes, interventions and tools (including laws) that (re)produce unequal distributions of water (Boelens et al., 2018). This includes injustices related with the distributions of goods and bads (distributional justice), with inclusion/exclusion in decision-making (procedural justice), and with recognition and legitimization of political, social, and cultural standings and values (recognitional justice). The latter includes exposing how dominant actors (try to) impose belief systems and truth regimes on how water and socio-natural relations should be understood and governed, typically by excluding and assimilating alternative modes of representation and knowledges (see for instance Linton, 2010; Boelens, 2014; Linton and Budds, 2014; Boelens et al., 2016). These contested belief systems and regimes of truth contribute to define and order specific hydrosocial configurations that is the networks of humans, water flows, ecological relations, hydraulic infrastructure, financial means, legal-administrative arrangements, and cultural institutions and practices (Ferry and Limbert, 2008; Boelens et al., 2016; Swyngedouw and Boelens, 2018).

The hydrosocial literature has contested the “modern” paradigm of water and hydrological cycles proper to the western hydrological scientific discourse (Linton, 2010; Boelens, 2014; Budds et al., 2014; Linton and Budds, 2014; Hommes et al., 2016). Likewise, hydrosocial research has devoted growing attention to analyze waters' multiplicity that is “the particular conditions and circumstances out of which various meanings, or practices, emerge, giving rise to different waters” (Linton, 2022, n.a.). This in turn entails studying the “temporal menagerie of meaning, materiality and legal structure through which water becomes known when different regimes of exploitation and extraction become attached to it at various points in history and cascade forward in time” (Vogt and Walsh, 2021, p. 1). Importantly, different water here refers not merely to different representations of water but different underlining realities of water itself, or different ontologies (Bonelli, 2017; Yates et al., 2017; Jerez et al., 2021; Linton, 2022; Ramos and Tironi, 2022). Laws, regulations and legal frameworks more in general play a significant role in the process of defining water(s) and in shaping its allocation and access. For instance, Zurita et al. (2015) show how different definitions of water are embedded in and constructed by various EU legislations, including the European Water Framework directive. Bakker et al. (2018) show how regulatory frameworks work to exclude Indigenous groups with respect to water allocation in Canada. In the Latin American context, the works of Boelens and Prieto, for example, have explored how legal definitions and regulatory systems interact with the plurality of local water rights present in the region and analyzed the associated diverse dynamics of symbolic and material water disciplining, resistance and resurgence (Vos et al., 2006; Boelens, 2009, 2014; Prieto, 2015, 2016).

How hydrosocial relations are shaped by laws and regulatory practices and processes is the focus of critical legal water geographies research. This field builds on wider legal geography work on the symbolic (or “nomic”) power of laws and on how law shapes territories through discourses and practices (Blomley, 1994, 2003; Delaney, 2010, 2015; Braverman et al., 2014). When applied to the study of water regulation and governance, the legal geography lens demonstrates how various legal discourses, frameworks and maneuvers contribute to shape hydrosocial configurations and produce socioenvironmental and economic injustices. Laws and legal frameworks are analyzed as socially and historically situated, products of social power, and productive of specific water and society relations (Meehan et al., 2023). This approach has been employed to analyze domestic water access and water governance in the USA (Jepson, 2012; Cantor, 2016; Cantor et al., 2020) and, more recently, to analyze desalinization projects in Chile (Campero and Harris, 2019). The work of Campero and Harris (2019) is of particular interest for us for it focuses on Chilean water governance and it points at how legal ambiguities in relations to the definition of waters—in their case desalinated seawater—open the space for various interpretations. They show how one of the basic techniques of legal interpretation or integration, legal coupling—that is “the insertion of one legal framework into another in order to fill gaps” (Campero and Harris, 2019, p. 5)—has significant consequences in shaping hydrosocial relations.

Beyond the work of Campero and Harris (2019), a wide body of hydrosocial research has analyzed Chilean waters. Several studies have focused on the effects—in terms of access to and distribution of water—of the application of the private property regime enshrined in the Water Code, making visible processes of dispossession and water appropriation in favor of productive activities (mainly agriculture and mining) in indigenous and non-indigenous territories (Budds, 2008, 2009, 2010; Prieto, 2015, 2016, 2022; Romero-Toledo and Jenkins, 2022). Researchers have also studied how hydrological knowledge has played an important role in the production of unequal water geographies by imposing a technocratic understanding of water management, excluding local knowledges and imaginaries and the social complexity linked to water (Budds, 2009; Usón et al., 2017). Hydrosocial approaches have been applied to the study seawater (Campero and Harris, 2019; Fragkou and Budds, 2020) and, more recently, mineralized groundwater (Jerez et al., 2021).

Taken together, legal geography and hydrosocial approaches allow for further understanding of who and based on what (legal and technical) assumptions and knowledge systems designs, control and have the power to (re)produce specific hydrosocial configurations. In the case of lithium mining, it enables us to scrutinize how legal loopholes and techno-legal frameworks have facilitated public-private mining interests to push a particular interpretation of mineralized groundwater. Once put into practice, the legal definition imposed has allowed its promoters to (re)configure water governance and the articulation and disciplining of discourses that sustain the current hydrosocial configuration of the salt flat basins.

The analysis focuses on legislation related with water and mining and on the three single lithium projects that currently have an Environmental Qualification Resolution (RCA) to extract mineralized groundwater in salt flats.³ The RCA is the official document that certifies that the project complies with environmental regulations and thus can be implemented. In this section we first briefly introduce the three projects and subsequently we describe the research methods. The location of these projects is illustrated in Figure 1 and their environmentally authorized extraction quota of brine and freshwater in Table 1.

Two of the mining projects we consider operate in the Salar de Atacama, the largest producing brine deposit in the world (Cabello, 2021). Both projects are characterized by a long history that goes back to the 1970s when explorations for lithium in the salt flat was initiated by the Chilean Economic Development Agency (CORFO). Both projects operate under contracts that CORFO established with two mining companies: MINSAL (today SQM Salar S.A.) and Sociedad Chilena de Litio (today Albermarle Lim.). Both projects underwent several changes in ownership and management over time shaped by political shifts in Chile particularly the neoliberal turn of the 1980s (for a historical overview see Poveda, 2020). The first project has been operating since 1996 and it is currently run by the Chilean company Sociedad Química y Minera de Chile (SQM), the second-largest lithium producer in the world and partially owned by the Chinese Tianqui. SQM extracts lithium and other minerals such as potassium. The second project has been operating since the 1984 and since 2015 it is run by the American Albemarle Corp. the largest lithium producer in the world. SQM and Albermarle pay rents and royalties to CORFO according to contracts renewed between 2016 and 2018 in a process not without controversy (CORFO, 2018; Poveda, 2020). In the study we consider a third project, “Proyecto Blanco” (in English, White Project). This project is located in the Salar de Maricunga and will be operated by Minera Salar Blanco (MSB) who owns the mining concession. The construction of the project should start in 2023. The project received the first RCA for lithium and potassium operations granted by the State environmental authorities outside the Salar of Atacama.

All three project have—or will have in the case of MSB—profound impacts on local communities, particularly indigenous people. The projects are located in recognized or claimed indigenous territories. MSB's project is located in the ancestral territories claimed by the Colla people, communities involved in small scale agriculture, livestock grazing, and transhuman pastoralism (Flores Fernández, 2021). Meanwhile, SQM and Albemarle operate in the territories of the several indigenous groups collectively referred to as Atacameño/Lickanantay under the 1993 Indigenous Law. Under the same law, the so-called Atacama La Grande Indigenous Development Area was created in 1997.⁴ The Atacameño/Lickanantay practice traditional Andean terraced agriculture, livestock grazing, petty trade and some work as laborer in mining companies (Budds, 2010; Liu and Agusdinata, 2020). Some Atacameño/Lickanantay communities are reunited under the Consejo de Pueblos Atacameños (CPA). The CPA works as an indigenous association and it involves representatives from 18 indigenous communities (Río Grande, Machuca, Catarpe, Quitor, San Pedro de Atacama, Solcor, Larache, Yaye, Séquitor, Cúcuter, Coyo, Toconao, Talabre, Camar, Socaire, Peine, Solor y Huatín). Each community is represented by two members. The CPA seeks to express a single “indigenous voice” however its legitimacy in representing the Atacameño/Lickanantay people has been questioned by some communities (Lorca et al., 2022). Water has significant productive and symbolic-cultural meaning for indigenous communities who mobilize local rules and customary practices (costumbres) to recognize water as sacred subject and ensure its continuous flow, the success of crops, and community ties (Prieto, 2016).⁵ The indigenous communities of the Atacama and Maricunga salt flats share a growing concern for the consequences that the extraction of brines has and will have on water, water-bodies, and ecosystems (Flores Fernández, 2021; Lorca et al., 2022). However, within and between different indigenous groups there are ambivalent positions with respect to the engagement with lithium companies and different strategies have been used including elements of both resistance and negotiation to respond to extractivism (Romero-Toledo, 2019; Jerez et al., 2021; Lorca et al., 2022).

The analysis is based on data obtained through interviews and the review of laws and documents related to plans and projects aimed at expanding lithium mining and extracting other minerals in Chilean salt flats. The first author carried out 25 interviews in 2021 and 2022. Interviewees include hydrologist and legal experts, members of civil society and State administrations including the Ministry of Mining and the General Directorate of Water (Dirección General de Aguas, DGA) that is the public agency in charge of water resources and basin management. Interviews focused on salt flat mineralized groundwater's legal and regulatory aspects and socioecological consequences of its extraction. Document review included legal texts such as the Chilean constitution, Chilean and foreign mining and water laws and regulations and a wide series of publicly available reports from governmental, judicial and administrative agencies related mainly to the three mining projects, particularly the environmental impact assessments. The analysis focused on how and if mineralized groundwaters are defined (as waters or mineral resources) as well as how their extraction is related with the extraction of other waters. As these documents are written in Spanish, the quotes we report below are our own translations.

In Chile, no specific legal framework regulates the extraction and use of minerals—like lithium and potassium—from mineralized groundwaters (Min. Minería, 2020a,b). Strictly speaking, as suggested by the quote above, mining legislation focuses on static mining deposits and not on liquid ones, like mineralized groundwaters. At the same time, as groundwaters, in principle, they should be governed by the Water Code, which stipulates that its provisions apply indistinctly to all terrestrial waters, both surface and groundwater. However, it has been considered that the Water Code does not explicitly recognize mineralized groundwater-brines as waters (Tala, 1994). This has left space for interpretation when it comes to the regulation of mineralized groundwater or brine extraction in salt flats.

In the absence of a dedicated legislation, the current prevailing interpretation extend mining legislation to salt flats and their mineralized groundwaters. The normative basis for this interpretation is found in the norms of the Constitution of 1980 and the 1983 Mining Code. According to these regulations, salt flats are part of the State mining patrimony: “the State has absolute, exclusive, inalienable and imprescriptible dominion over all mines, meadows, metalliferous sands, salt flats, coal and hydrocarbon deposits and other fossil substances, except for surface clays” (Chilean Constitution, article 19 No. 24, paragraphs 6 and Mining Code, article 1). In this sense, salt flats could be understood as another type of static mining deposit (Tala, 1994, p. 45; Min. Minería, 2020b, p. 5; Jerez et al., 2021). Specifically, the eminently “mining nature” of brines has been indicated by recent reports commissioned by the Ministry of Mining as linked to the provision contained in the Mining Code Regulations (art. 60), which define salt flat as “a superficial saline deposit, consisting of a saline crust of variable thickness, with occluded saline solutions (…)” (Min. Minería, 2020b, p. 13). Thus, mineralized groundwater could be defined as “occluded saline solutions” (not as water resources) and as constituent part of the salt flat being, therefore, a mining resource within mining deposits (Min. Minería, 2020a, p. 36; Min. Minería, 2020b, p. 13, 32).

Constitutional mining norms added that the law would define which substances may be subject to mining concessions for exploration or exploitation to private parties and which would be reserved for the State (Chilean Constitution, art. 19, No. 24, paragraphs 7). Lithium has fallen into this category since 1979 when it was declared as non-concessionable mineral (Decree Law 2.886 art. 5). This means that lithium extraction and exploitation can be carried out only by the State or its companies, under administrative contracts or special lithium operation contracts (CEOLs).⁶ Following the purely mining logic, the mining concessions and contracts include the right to explore or exploit and even evaporate mineralized groundwater from the salt flat they cover (Tala, 1994, p. 45; Min. Minería, 2020b). According to Tala (1994), the above interpretation is justified since in these cases the extraction of such water does not have a “water purpose” as such, but is carried out as a necessary activity to exercise the rights derived from the mining permits and in order to appropriate the minerals (Tala, 1994, p. 44).⁷

A legal classification and treatment of salt flats as mineral deposits and brines as mining resources has important implications in the (re)configuration of hydrosocial relations. First, the State has ownership on salt flats and its mineralized groundwaters and may grant mining concessions, administrative contracts, CEOLs or explore and exploit them directly or through its companies depending on the mineral substances to be obtained. Moreover, it should be noted that the processes for the constitution of strictly mining concessions and permits do not consider environmental aspects, citizen participation or possible indigenous consultation. Therefore, they can be granted directly on, for example, protected areas or indigenous territories.⁸

Second, authorizations for extraction of mineralized groundwaters in salt flats for mining proposes do not follow the procedures established by the Water Code for the constitution of groundwater exploitation rights. Instead, the quotas to be extracted are defined and authorized within the environmental assessment processes of mining projects following the System of Evaluation of Environmental Impact Assessment System (Sistema de Evaluación de Impacto Ambiental, SEIA).⁹ As functionaries of the DGA explained to us: “there is a special extraction of brine that is governed by a different legal regime... what is water extraction is under the tutelage of the DGA through water use rights and what is brine extraction is regulated through the environmental impact assessment system carried out by the Environmental Assessment Service [SEA]” (in similar vein DGA, 2021a, p. 196). According to the SEA, projects for the exploitation of lithium and other mineral substances must enter the SEIA based on the typology of mining projects and the amount of brine extracted (classified as a mineral by the SEA) (SEA, 2021, p. 15).¹⁰ In the assessments, the socioenvironmental impacts of projects are evaluated based on studies prepared and submitted by mining companies for the sole and exclusive purpose of obtaining an environmental license to operate (Broitman and Kreimer, 2018), including hydrological models, simulations and measurements or mathematical calculations (SEA, 2021). If the presented information is approved, the projects obtain his environmental license (RCA).

A third implication, resulting from the previous one, is that the extraction of brines from salt flats is managed separately from fresh and lower salinity water extraction, which are categorized and treated as a water resource according to the Water Code. For this reason, mineralized groundwater and its interactions with lower salinity aquifers have not been subject to greater analysis or integrated into the DGA's studies, models and water balances, an issue that has recently been attempted to be partially rectified, at least for the Salar de Atacama (CORFO, 2021; DGA, 2021a). By not applying water law restriction, permits to extract and consume brine may be obtained in basins with insufficient water balances. They may also not be declared as depleted or areas prohibited for the constitution of water rights. According to Jerez et al. (2021, p. 8) “by not explicitly recognizing brine as a water entity in legal terms but as mining property, the hydrosocial impacts of brine exploitation are invisible, and only the freshwaters of the salt flat are considered.”

Lithium companies have promoted the legal interpretation of mineralized groundwaters as mining resources by publicly denying their water character (SONAMI, 2017; SQM Salar S.A., 2021a, p. 08). In official reports published, mining companies argue that extracted brines cannot be considered water resources because they contain more than 300.000 mg/L of total dissolved solids (TDS; ten times more than seawater). Therefore, the argument goes, they are unsuitable for human consumption or activities related to agriculture and livestock (SQM Salar S.A., 2021a; Albemarle, n.d.). Mining companies take as a reference water quality standard for irrigation water (Chilean norm 1333) and drinking water (Chilean norm 409) that establish corresponding maximum concentration limits of 5.000 and 1.500 mg/L respectively (SQM Salar S.A., 2021a). Thus, water that evaporates after extraction is not considered as part of water consumption by lithium companies, which point out that their operations consume practically no freshwater (SONAMI, 2017; Bustos-Gallardo et al., 2021; SQM Salar S.A., 2021a; Albemarle, n.d., p. 08). As we show below, the legal interpretation of brines as mining resources separates from water resources is used and reaffirmed by mining companies in the environmental impact assessments of mining projects. In these studies, “brine” aquifers are conceptualized as hydrogeological structures separated or mainly disconnected from the freshwater-brackish aquifers. This is in turn, the basis used to rule out or minimize the impacts on water resources, hydrological systems and related local community practices and livelihoods. This interpretation is, however, contested by some indigenous groups and others who rather support an understanding of brines as (a type of) waters.

The fact that a legal loophole nourishes the current legal treatment of mineralized groundwaters as mineral resource opens the door to alternative interpretations. Below we review two of them, starting from a recent attempt commissioned by State institutions to define the legal nature of brines and to recognize the brines/water interconnection. The second interpretation instead is based on understanding of brines as a type of water supported by indigenous groups and part of the academic community.¹²

In this article, we analyze how different legal interpretations and definitions of brines shape the regulation, governance and assessment of the socioecological impacts of lithium mining and other minerals in Chilean salt flats and wetlands. In the absence of specific legislation, mining companies and State agencies have extended mining legislation to brines through a process of legal coupling. As a result, brines are treated for all legal proposes as mineral resources and not as waters. Such interpretation has been consolidated through studies developed by mining companies and endorsed by State authorities as part of the environmental impact assessments of mining operations. In these studies, brines and freshwaters of the salt flats are conceptualized as separate entities on scientific grounds that are currently the subject of intense scrutiny. This, in turn, has made it possible to argue that the extraction of brine does not affect water resources and wetlands part of the salt flat ecosystems and, therefore, the people and biodiversity that depend on them. The treatment of brines as minerals and the consequent definition of the impacts of their extraction has also contributed to excluding and/or co-opt alternative ways of conceiving brines as a type of waters and the salt flat and wetlands as an integrated and interconnected ecosystem. We show that alternative interpretations are not only possible and are being put forward by (some) State institutions, by indigenous groups and researchers but also that these interpretations are legally sound.

In conclusion, we offer some reflections on how our analysis contributes to further understanding and problematizing lithium mining in Chile and beyond. First, our work sheds further light on the internal logics and importance of legal definitions and frameworks in the hydrosocial configuration of lithium mining, which has been highlighted by other works on the subject (Babidge et al., 2019; Bustos-Gallardo et al., 2021; Jerez et al., 2021; Blair et al., 2022; Hernandez and Newell, 2022). As Campero and Harris (2019), we show that legal coupling is a powerful tool with outcomes that transcend the legal realm and influence environmental impact assessments and, ultimately the material practices of lithium extraction. In fact, defining mineralized waters as minerals—legally but then also technically in EIAs and EISs—is the basis for conceiving brine flows as separate from other water flows, lithium mining as a low water impact industry, and structuring the current exploitation regime in salt flats focused on fractional governance of waters in the basin (see also Bustos-Gallardo et al., 2021 and Jerez et al., 2021). The shortcomings of the current way of understanding the functioning and water balances of the salt flats and ecosystems and the impact of lithium mining have been criticized and demonstrated (SMA, 2016; First Environmental Court, 2019; Liu et al., 2019; DGA, 2021a; Gutiérrez et al., 2022). Based mainly on the conception of salt flats' freshwater separated from brines, it is possible to allow brine extraction in basins with deficit water balances as the Salar de Maricunga and generating extreme situations in hydrogeological balances as in the Salar de Atacama (CORFO, 2021; DGA, 2021a).

Second, we show that the legal interpretations—and the hydrosocial configurations they underprint—are contestable and contested. As a Meehan et al. (2023) write in a recent book, “law is a battlefield, a site of struggle” (p.51). While mining companies back the interpretation of brine as a mineral and on this, they build a particular understanding of hydrosocial relations in the Salar de Atacama and Maricunga, indigenous groups put forward different understandings of brine as a type of water. However, these conceptions remain marginalized at least regarding to the impact assessments and other formalized water decision-making processes where they are raised (see DGA, 2021a,b). Alternatively, they tend to be assimilated into the prevailing approach through corporately driven participatory and consultative mechanisms. In between, we find proposals developed for public mining institutions highlighting brines' water character by promoting a hybrid interpretation. Legal frameworks play a role in reproducing but also tackling water injustice as they can open up and/or close down spaces of contestation (such as the processes of citizen participation and indigenous consultation in the SEIA). Laws and regulations could also be used to support alternative interpretations, for example, using legal coupling to make applicable to brine the rules of the Water Code and groundwater regulations. This could lead to changes in the hydrosocial understanding of the salt flats including a more holistic conception of water flows above and below the ground. It could also contribute to address water injustices by fostering involvement of local communities, especially indigenous people and their knowledge systems in decision-making related with lithium mining.

Third, although regulatory alternatives on brine count with solid legal basis, introducing an explicit recognition of brine's water character seems (still) far from governmental priorities. From a legal perspective, this would not require a new law but only a new regulation (which could be introduced by the current government without need parliamentary approval). Instead, the focus of the debate tends to be on the appropriate business model to push forward and expand lithium mining in the short and medium term and take advantage of the boom in price and demand at almost any cost. In this sense, although creating a strong State-owned company was one of the campaign banners of the current government, more expeditious public-private partnership modalities close to those currently operating are gaining greater importance within the non-participatory, announced and delayed new National Lithium Strategy. Whichever option is finally adopted, socioenvironmental impacts will probably continue to be addressed as externalities to be managed within environmental assessment processes and contracts or agreements between local communities, mining companies and eventually the State leading to the adoption of the social and environmental license. As a result, mineralized groundwaters will continue be treated as minerals and salt flats and wetlands ecosystems affected and threatened by lithium mining will likely continue to be considered “green sacrifice zones” (Zografos and Robbins, 2020; Jerez et al., 2021; Sovacool, 2021) and water injustices perpetuated. An open debate on the different interpretations of brine is much needed, given their implications for assessing the socioenvironmental impacts of mining operations. We see the space for formal recognition of brines as waters and suspect that this would allow for better evaluating impacts on ecosystems, biodiversity, human rights and traditional lifestyles. These impacts are undoubtedly at the heart of the socioenvironmental contradictions, inequities and injustices linked to lithium mining in salt flats, both Chile and its neighboring countries, which seeks to exploit their groundwater for the sake of the green energy transition.

This brings us to our fourth and final point, the lack of an unequivocal definition and regulation of brines and lithium mining does not only regard Chile. Argentina and Bolivia, which host the largest lithium resources in their salt flats (USGS, 2023), also lack specific regulations, so analyses like this one would be pertinent and relevant. As in Chile, mining regulations apply mainly by extension to brine mining, but with greater intervention of the water authority in authorizations for certain cases (Lopez Steinmetz and Fong, 2019; Min. Minería, 2020b). In Nevada, United States, the extraction of all groundwater for mining production without distinction has a specific regulation requiring water rights (Min. Minería, 2020b), while in Canada regulations and definitions vary across provinces (Tscherning and Chapman, 2021). Given that lithium mining in salt flats is receiving increasing attention internationally, paraphrasing Linton (2010), it is essential to ask the question: what is brine? We show that how this type of groundwater is defined, by whom and through what legal frameworks shapes how its flows and the socioecological impacts of lithium mining are understood, assessed, and addressed. Clearly, brine (as water) escapes singular definitions; it lends itself to be understood as a mineral resource and/or as a type of water or another. Defining brines is thus a highly political process where laws but also knowledge practices—like modeling and legal analysis—play a role. This recognition is necessary to critically analyze the multiple discursive and material dynamics that frame new forms of water and nature appropriation and their highly uncertain socioenvironmental impacts. Especially those linked to new technological developments such as green hydrogen or, in this case, lithium water mining in salt flats, which are based on the intensive exploitation of saline or mineralized waters. These kind of debates and analyses are needed to be aware of and responsible for the effects of perpetuating an economic model based on extraction and to prevent that solutions to the climate crisis end up exacerbating the current biodiversity and socioenvironmental crises.

The datasets presented in this article are not readily available because, due to the sensitive nature of the research, supporting data is not available. Requests to access the datasets should be directed at: florescr@hu-berlin.de.

Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. Written informed consent from the participants was not required to participate in this study in accordance with the national legislation and the institutional requirements.

CF developed the research design, the data collection and analysis, and the first draft of the article. RA contributed to the analysis, the revision, and editing of the article. Both authors contributed to the article and approved the submitted version.