In several Latin American countries, the state has to consult impacted Indigenous communities before approving new hydrocarbon and mining development, in accordance with regulations that govern these “prior consultation” processes. However, when navigated by extractivist states, these formal norms have blocked the very participation they were intended to encourage and have facilitated state disregard of both Indigenous territorial rights and the environmental destruction caused by large-scale development. These unanticipated outcomes stem from the measures the state must take to determine whether a hydrocarbon or mining project directly impacts an Indigenous community and therefore requires prior consultation. To make this determination, the state must define lands to which Indigenous communities hold rights, and the area impacted by the proposed development. State agencies that are eager to approve new extraction have overlooked – and in some cases actively dismissed – both the impacts of mining and hydrocarbons, and the geographical reach of Indigenous authority, in contexts in which communities claim, but lack title to damaged lands. This chapter demonstrates how prior consultation has encouraged the state to overlook, and even actively deny, Indigenous territorial rights and environmental impacts of extraction through analysis of three important Indigenous mining and hydrocarbon conflicts in Bolivia, Colombia, and Peru.

The intersection between energy and the environment is regulated on the basis of legal foundations that international economic law has developed on its own or ‘borrowed’ from (or otherwise relied on) such outside regimes as general international law and international environmental law. The borrowed principles, like sovereignty over natural resources or sustainable development, can find their reflection, directly or indirectly, in trade and investment agreements and case law and will continuously affect new developments in this field. This chapter will show that such foundations stemming from the external sources define the basic contours of State’s rights and duties associated with the energy–environment nexus. Moreover, the international trading and investment systems provide self-created legal foundations for environmental policy space as will also be discussed in this chapter. They define the extent to which energy-related restrictive measures driven by environmental considerations can be accepted. The case of the ECT presented at the end of this chapter is a striking example for demonstrating that the legal foundations are not static and may undergo important changes.

As a preliminary issue, this chapter argues that the DSM regime embodies a dual-track regulatory system where national regulation by the sponsoring State plays a subordinate role complementary to international regulation of the ISA. Thereafter, it examines a network of international environmental obligations of the sponsoring State under the overarching principle of sustainable development, in accordance with both lex specialis of DSM and general international environmental law, drawing on the Seabed Disputes Chamber’s Advisory Opinion of 2011. That covers the sponsoring State’s obligation of prevention, obligation to apply the precautionary approach and obligation concerning environmental impact assessment (EIA). Then, it turns to the contractor, investigating its international environmental obligations to conduct EIAs and submit EISs, to prepare for and respond to environmental emergency, on environmental management and monitoring and to apply the highest environmental standards. The latter part refers frequently to the 2019 draft Exploitation Regulations and the still to be adopted Phase 1 Standards and Guidelines of the LTC.

This Chapter discusses the legality of proposed plans to utilise icebergs as an alternative source of freshwater. This is an example of emerging demands on the oceans which need to be regulated by an adequate rule of law. The Chapter maintains that UNCLOS does not adequately regulate the potential use of icebergs. The only limitations are that States cannot utilise icebergs found in the maritime zones of other States and must observe the obligations under Part XII of UNCLOS to protect the marine environment. The Chapter also analyses the relevant instruments within the Antarctic Treaty System. None of these instruments indicates a prohibition against the use of icebergs. The only limitation is one of conducting an environmental impact assessment. Therefore, the Chapter identifies a gap in the regulatory capacities of international law. In addressing this gap, the Chapter discusses the potential of ongoing BBNJ negotiations.

This chapter examines the ICJ’s influence on international environmental law. Drawing on concrete examples, the author identifies six ways in which the Court’s jurisprudence has contributed to environmental law: by articulating foundational principles; by acting as a gatekeeper for customary international law; by elaborating existing principles; by interpreting environmental agreements; by valuing environmental harms; and by incorporating environmental considerations into other areas of international law. The author reflects on potential future evolutions of the Court’s role in the international environmental law space, given the increasing number of disputes that the Court has addressed in this field in recent years.

The protection of marine environment assumes a special place under UNCLOS. Part XII provides for general obligations to protect and preserve the environment as well as more specific provisions concerning the prevention, reduction and control of marine pollution, including those relating to different sources of pollution. At the same time, Part XII is intended to provide a general framework for the protection of the marine environment. This framework nature is demonstrated not only by the existence of many generally-worded provisions and open-ended obligations which need to be further elaborated but also in the existence of numerous reference to external rules and standards, international organisations and regional arrangements. This chapter examines the contribution of UNCLOS tribunals to clarifying the scope and content of the general obligation to protect and preserve the marine environment before moving to discussing the extent to which UNCLOS tribunals have shed light on the normative content of three key environmental obligations and principles in the context of the marine environment.

This chapter provides an understanding of where international law is at (including customary international law, treaty and case law) in terms of its achievements and shortcomings regarding cooperation over environmental protection and use of transboundary freshwater ecosystems. This work provides a basis for critical analysis over the proceeding book chapters, in relation to the value added by the UNECE. The chapter lays the foundations for determining the UNECE regime’s relationship to international water law, international environmental law and general international law. It explores the role of international courts and the international law commission in interpreting outdated water treaties and bringing their standards of environmental protection closer to contemporary scientific understandings and the more progressive multilateral environmental agreements in accordance with the principle of systemic integration. It also explores instances where Courts have arguably has not gone far enough, leaving gaps in understanding. Unlike Courts, pan-regional or basin treaties and their river basin commissions can develop and interpret rules and principles of international water law on a continual and comprehensive basis and provide the institutional framework which supports implementation and compliance with international water law. This hypothesis, on the added value of the UNECE water regime, is tested over the proceeding chapters.

An increasing number of jurisdictions are using environmental impact assessment as a tool for climate change mitigation (in brief, ‘Climate Assessment’, or CA). This chapter debates whether this is a legal obligation, or whether this even makes sense. Benoit Mayer argues that CA is emerging as a rule of customary international law, and that, moreover, it is a potentially useful mitigation tool. Alexander Zahar, by contrast, questions the meaningfulness of CA, arguing that it is impossible to determine what constitutes a significant, excessive, or disproportionate emission of greenhouse gases in the case of a proposed activity subject to CA, or at all.

An increasing number of jurisdictions are using environmental impact assessment as a tool for climate change mitigation (in brief, ‘Climate Assessment’, or CA). This chapter debates whether this is a legal obligation, or whether this even makes sense. Benoit Mayer argues that CA is emerging as a rule of customary international law, and that, moreover, it is a potentially useful mitigation tool. Alexander Zahar, by contrast, questions the meaningfulness of CA, arguing that it is impossible to determine what constitutes a significant, excessive, or disproportionate emission of greenhouse gases in the case of a proposed activity subject to CA, or at all.

Chapter 4 examines the development and operation of the environmental assessment legal regime, with a focus on the Environmental Impact Assessment Law (EIAL) (2018). Environmental impact assessment (EIA) evolved from a project-based pollution prevention instrument under EPL (for trial implementation) (1979) to a technical and statutory process that implements both the preventative principle and participatory principle for projects and plans under EIAL (2002). The chapter analyses project EIA, the statutory process that aims to incorporate both science-based evidence and public input for sound and well-informed decision making by the approval authorities. It further explores strategic environmental assessment (SEA) including the environmental assessment of government plans and policies. The importance of public participation in both EIA and SEA cannot be overstated and deserves in-depth examination for further improvement. The chapter concludes with comment on closer integration between SEA and project EIA to enhance both efficiency and effectiveness of the environmental assessment regime.

Large dams are emerging drivers of landscape-scale habitat fragmentation, causing extensive flooding and transforming hilltops into islands. Environmental Impact Assessments (EIAs; the process to assess and account for impacts of development) do not explicitly consider reservoir islands in calculations of habitat impacted by dam construction. Reservoir islands maintain relict biological communities from the previously continuous habitat. Relict communities are subject to an extinction debt whereby species are lost over time. We demonstrate how estimating the ‘conservation value’ of islands (CV; the proportion of relict continuous habitat [forest] species on islands) using relict species–area relationships (RSARs), can be used in an area-of-impact correction tool to account for insular habitats in EIAs. We used data from eight taxonomic groups within the Balbina Hydroelectric Reservoir (BHR) archipelago in Brazilian Amazonia. We found ca. 72,000 ha of insular habitat had reduced CV, equating to 60% of aggregate island area, and that an additional 24% of the ca. 300,000 ha BHR water surface area should be included in area assessments for impacted terrestrial habitat. Where reservoir island creation is unavoidable, using RSARs to assess the CV of islands enables more accurate and dynamic assessment of the ecological impacts of dam construction.

Embedded in this analytical framework, the fifth chapter is dedicated to an analysis of how due diligence obligations are applied and implemented in different areas of international law. Since the standard of due diligence is highly context-specific, problems and prospects related to its application are best illustrated by taking a closer look at the standard’s implementation in concreto. To this end, three fields of international law are singled out in which due diligence obligations have already been prominently discussed and which show certain similarities to the area of human rights law: the protection of the environment, the fight against terrorist activities, and rather recently the combat against harmful cyber activities. Based on the analytical framework introduced in the previous chapter, the application of due diligence obligations is discussed for each field taking into account the relevant state practice, international jurisprudence, and scholarly writings.