The environment as an object of protection

The meaning and scope of the “environment” has not been uniformly defined in international law. Sources of a legal definition of the environment can be found in international agreements, international jurisprudence and the views of highly respected jurists of public international law, such as the ILC.Footnote ¹³ In the following analysis, only treaties that explicitly and directly regulate the protection of the environment during armed conflict are introduced.

Under the international humanitarian law regime, the sources of law on the definitions of direct relevance to the protection of the environment in relation to armed conflict are limited to three major treaties: the Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques (ENMOD Convention), Articles I and II;Footnote ¹⁴ AP I; and the Rome Statute of the International Criminal Court (Rome Statute).Footnote ¹⁵ AP I (Articles 35(3) and 55) and the Rome Statute (Article 8(2)(b)(iv)) use the term “natural environment”, but neither includes a definition of this term. Prohibiting the use of the environment as a “weapon”, or more accurately, as a “method” of warfare,Footnote ¹⁶ the ENMOD Convention provides significantly wider protection for the environment by requiring a much lower threshold of damage than that required by AP I.Footnote ¹⁷ However, the range of techniques covered by the ENMOD Convention appears to be restrictive,Footnote ¹⁸ and it does not address the scope of the environment as a target – i.e., the range of targets protected from “destruction, damage or injury”.Footnote ¹⁹ None of the widely ratified in bello treaties defines the environment, and provisions on the natural environment in those treaties are framed mostly in anthropocentric termsFootnote ²⁰ or only by reference to the term “natural environment”. However, an examination of the law of armed conflict does not reveal the exact meaning and scope of this term – that is, what exactly is protected as the “natural environment”.Footnote ²¹

In addition to the limited protection offered by international humanitarian law, rules of international environmental law show much potential in safeguarding the environment against wartime damage. Certain environmental treaties remain applicable in times of armed conflict;Footnote ²² more generally, environmental treaties or multilateral agreements can complement and strengthen environmental protection when an armed conflict occurs.Footnote ²³ Although the definitions of “environment” differ in various environmental treaties and depend on the subject matter of each treaty, a close look at the provisions of the environmental treaties indicates that environmental protection can extend to the intrinsic value of natural ecosystems.Footnote ²⁴ For example, under the United Nations (UN) Convention on the Law of the Non-Navigational Uses of International Watercourses,Footnote ²⁵ the term “environment” is intended to encompass the living resources of international watercourses, the flora and fauna dependent upon those watercourses, and the amenities connected with them.Footnote ²⁶

The work of the ILC denotes an acknowledgment of a broader concept of the environment. Typically, the 2006 Draft Principles on the Allocation of Loss in the Case of Transboundary Harm Arising out of Hazardous Activities prescribes a broad definition of the environment that “includes natural resources, both abiotic and biotic, such as air, water, soil, fauna and flora and the interaction between the same factors, and the characteristic aspects of the landscape”.Footnote ²⁷ According to the ILC, “[e]nvironment could be defined in different ways for different purposes and it is appropriate to bear in mind that there is no universally accepted definition”.Footnote ²⁸ Further, the Commission has opted to include in the definition “environmental values” and “non-service values” such as the enjoyment of nature and recreational attributes and opportunities.Footnote ²⁹

The recent practice of international courts and tribunals is also encouraging in broadening the scope of the environment and allowing reparations for pure environmental damage, namely damage caused to the environment, in and of itself. In its Advisory Opinion in the Nuclear Weapons case, the International Court of Justice (ICJ) eloquently noted that “the environment is not an abstraction but represents the living space, the quality of life and the very health of human beings, including generations unborn”.Footnote ³⁰ Later, in the proceedings of the United Nations Compensation Commission (UNCC), despite not attempting to define the term “direct environmental damage” in UN Security Council Resolution 687, the Panel of Commissioners, in regard to environmental claims, accepted claims for a non-exhaustive list of losses or expenses in relation to environmental damage.Footnote ³¹ The Panel explicitly stated that “there is no justification for the contention that general international law precludes compensation for pure environmental damage”.Footnote ³² In the Iron Rhine case decided by the Permanent Court of Arbitration, “environment” was broadly referred to as “including air, water, land, flora and fauna, natural ecosystems and sites, human health and safety, and climate”.Footnote ³³ In the Certain Activities and Armed Activities cases, the ICJ held that damage to the environment, in and of itself, is compensable under international law.Footnote ³⁴

As seen above, the traditional concern for the environment in the law on armed conflicts is framed largely in anthropocentric terms. Yet this narrow focus on immediate human needs may compromise the resilience of natural systems that supply essential environmental goods and services.Footnote ³⁵ In light of this, we will now consider how the rules and practices for environmental protection in relation to armed conflict have developed in tandem with the growth of the broadened definition of the environment in international law.

A dynamic approach to environmental protection

It is worth noting that the ILC takes a dynamic approach to the understanding of environmental considerations in relation to armed conflict. It underlines that “environmental considerations cannot remain static over time but should develop as understanding of the environment develops”.Footnote ³⁶ The evolving concept of the environment informs the notion of environmental considerations that should be taken into account in armed conflict. This dynamic approach is also instrumental in actualizing full reparation for environmental damage in the aftermath of an armed conflict.

On the one hand, a contemporary understanding of the environment conceives it as a dynamic system, rather than simply a collection of objects to be protected.Footnote ³⁷ The interactivity of the environment should be recognized in assessing wartime environmental damage. In its comments on the ILC Draft Principles, the International Committee of the Red Cross (ICRC) stated: “What is certain is that in assessing the degree to which damage meets the threshold, current knowledge, including on the connectedness and interrelationships of different parts of the natural environment as well as on the effects of the harm caused, must be considered.”Footnote ³⁸ On this basis, the ILC stressed that current scientific knowledge of ecological processes must be taken into account when applying the “widespread, long-term and severe” damage criteria against which the environment should be protected. To be more specific, “risk of damage should not be conceptualized only in terms of harm to a specific object but should also take into account the possibility of affecting a fragile interdependent system of both living and non-living components”.Footnote ³⁹

On the other hand, the broadened notion of the environment reflects a growing realization of the intrinsic link between human and natural systems. The distinction between the natural and man-made parts of the environment appears to be less apparent in current times.Footnote ⁴⁰ As a result, the modern definitions of the environment as an object of protection do not draw a strict dividing line between the environment and human activities but encourage definitions that include components of both.Footnote ⁴¹ The interactions between human and natural systems have been studied as coupled human and natural systems, which are defined as integrated systems in which people interact with natural components.Footnote ⁴² Based on the complex human–nature relationship, Payne calls for a consideration of how human activities and the environment function as an interactive system. Suggestions include defining liability and causation in terms that account for interactions within the system and considering the systemic effects of remedies provided.Footnote ⁴³

Adjusting the objective

In order to integrate the contemporary understanding of the environment, the goal of full reparation and its requirement of “re-establishing the situation that would have existed had the act not been committed” need to be specified in their application to wartime environmental damage. Despite being sparse, judicial practice concerning reparations for environmental harm can provide important insights.

It is noteworthy that re-establishing the prior situation does not simply imply restoring each and every component of the damaged environment to its pre-existing physical condition. In Certain Activities, Nicaragua removed approximately 9,500 cubic metres of soil from the sites in question, which were subsequently filled up and covered with vegetation. Under the fifth head of damage, Costa Rica claimed for the cost of replacement soil since the refilled sediment was of a poorer quality and was more susceptible to erosion. The Court determined that Costa Rica had not demonstrated that the difference in soil quality had an effect on erosion control, and thus that the evidence before the Court regarding the quality of the two types of soil was not sufficient to determine any loss which Costa Rica may have suffered.Footnote ⁴⁴ Based on this, the Court rejected Costa Rica's claim for replacement soil.Footnote ⁴⁵ Observably, here the determinative criterion for awarding the payment for restoration was not the fact that the soil that Nicaragua had removed was of a higher quality than the soil that has since replaced it. In order for the Court to identify and assess any loss that Costa Rica may have suffered, the evidence must have been sufficient to demonstrate how and to what extent the difference in quality between the two types of soil, if any, had affected erosion control. In other words, the purpose of re-establishing the pre-existing situation in this scenario is not to replace the soil with something of identical or comparable quality, but to retain the erosion control service offered by the site.

Not coincidentally, while relying on the general principles of State responsibility for guidance, particularly the principle that reparation must, as far as possible, wipe out all the consequences of the illegal act, the UNCC prioritized ecological functioning in determining the appropriate objective of remediation measures and reviewing the details of proposed remediation action.Footnote ⁴⁶ The Panel of Commissioners considered that, in assessing what measures are reasonably necessary to clean or restore a damaged environment, “primary emphasis must be placed on restoring the environment to preinvasion conditions, in terms of its overall ecological functioning rather than on the removal of specific contaminants or restoration of the environment to a particular physical condition”.Footnote ⁴⁷ Even if sufficient baseline information were available, the Panel reasoned, it might not be feasible or reasonable to fully recreate pre-existing physical conditions.Footnote ⁴⁸ The Panel further explained that “in some circumstances, measures to recreate pre-existing physical conditions might not produce environmental benefits and could, indeed, pose unacceptable risks of ecological harm”, and as a result, “where proposed measures for the complete removal of contaminants are likely to result in more negative than positive environmental effects, such measures should not qualify as reasonable measures to clean and restore the environment”.Footnote ⁴⁹ The UNCC's environmental decisions focused on the protection and restoration of environmental integrity and were based on the principles of precaution, common concern, obligations to future generations, and the value of ecosystems, in addition to long-standing principles of international law.Footnote ⁵⁰

The practice of the ICJ and the UNCC has demonstrated a nuanced but critical distinction between the objectives of “returning the environment to its original state” and “maintaining the overall ecological functioning of the environment”. Recalling that the proper objective of reparation for wartime environmental damage should take account of the contemporary understanding of the environment, the interactivity within the environment, and the coupling of human and natural systems, the principle of full reparation can be achieved through the objective of restoring the overall ecological functioning of the damaged environment.

The temporal scale for reparation

The question of temporal scale for reparation arises from the continuous and cumulative nature of wartime environmental damage. In her Preliminary Report on the Protection of the Environment in Relation to Armed Conflicts, Special Rapporteur Marie G. Jacobsson observed that the effect on the environment of an armed conflict may remain long after the conflict and has the potential to prevent an effective rebuilding of the society, to destroy pristine areas or to disrupt important ecosystems.Footnote ⁵² The ICRC also drew attention to the fact that damage to the environment due to armed conflicts may have long-term consequences that continue after the end of hostilities.Footnote ⁵³ As an illustration, in Kuwait and Saudi Arabia, the adverse effects of the oil well fires during the 1990–91 Gulf War were revealed more than ten years later in the form of desert covered with inches of oily residue that eventually hardened into a pavement-like substance, and lakes of oil that trapped livestock, birds and other wildlife.Footnote ⁵⁴ Another prominent illustration is the “zone rouge”, an exclusion area of France where World War I had a long-lasting impact on the environment; being completely destroyed by the Battle of Verdun, it is still deemed unfit for human habitation more than a century after the end of the hostilities. On the one hand, these examples shed an additional perspective on the importance of both the principle of precautions from the law of armed conflictFootnote ⁵⁵ and the precautionary approach from international environmental law.Footnote ⁵⁶ On the other, the long-term environmental impact of armed conflicts may take many years to unveil itself, and it will be far too late to wait until then to make reparation. Therefore, the appropriate remedy for such situations necessitates provisions for keeping reparations open-ended where the full extent or long-term impacts of environmental damage may not be immediately apparent, with an option to revisit the remediation process and implement additional measures if long-term effects emerge over time or are discovered.

An effective way to identify and assess long-term risks to the environment in relation to armed conflict so as to inform necessary future actions is to monitor the consequences during conflict and in its aftermath.Footnote ⁵⁷ In this regard, the ICRC suggests establishing possible mechanisms and procedures for addressing the immediate and long-term consequences of environmental damage.Footnote ⁵⁸ One of the unique features of the work of the UNCC is the implementation of comprehensive monitoring and assessment projects to ascertain the level of damage. As expressed by the Panel of Commissioners, even if the results generated show that no damage has been caused or that damage has occurred but remediation or restoration efforts are not possible or advisable in the circumstances, a monitoring and assessment activity could be of benefit. Also, such an activity could help to alleviate concerns regarding potential risks or damage and avoid unnecessary and wasteful measures to deal with non-existent or negligible risks.Footnote ⁵⁹

The UNCC Governing Council decided that “appropriate priority should be given to the processing of [the monitoring and assessment] claims” related to the Iraqi invasion of Kuwait.Footnote ⁶⁰ Such claims were grouped into the first instalment of environmental claims to be reviewed by the Panel of Commissioners, separately from the resolution of the related claims for environmental damage. But the monitoring and assessment programmes did not start until June 2001, ten years after Iraq's invasion and occupation of Kuwait. By this time claims had already been submitted for the third, fourth and fifth instalments. Accordingly, the Panel received and considered post-submission amendments when results from monitoring and assessment projects became available, changing the extent and nature of the damage and increasing the costs of proposed remediation substantially in some cases, while reducing it in others.Footnote ⁶¹

Limited baseline information

Addressing immediate and long-term consequences of environmental damage from armed conflicts raises novel questions about reparation.Footnote ⁶² Reliable information on the condition of the environment is hard to obtain due to mass destruction – to be specific, armed conflicts will lead to disruptions in environmental monitoring, data collection and information-sharing.Footnote ⁶³ In many instances, monitoring facilities and equipment are destroyed and ongoing tensions hamper data collection by rendering areas inaccessible.Footnote ⁶⁴ The complexity of the ecological processes adds to the difficulties in evidence-gathering, insomuch as the assessment of environmental impact often requires a lengthy and expensive process of discovery of damage undertaken by experts.Footnote ⁶⁵ To illustrate this, in the proceedings of the UNCC, a majority of the environmental claims were rejected not due to inadmissibility but for insufficient evidence,Footnote ⁶⁶ such as being inadequate in establishing baseline levels, in determining the proportion of damage attributable to Iraq's invasion and occupation of Kuwait or assessing the importance of other factors, in quantifying such damage, etc.

In situations of armed conflict, making reparation is complicated by a lack of baseline information for comparison between pre- and post-war conditions. The absence of accurate baseline data precludes the determination of the precise origin and extent of the environmental consequences of armed conflicts. In this connection, the UNCC Panel of Commissioners stated that baseline information on the state of the environment prior to the Iraq conflict may be inadequate, which makes it difficult in many cases to distinguish between damage attributable to the conflict and damage that may be due either to unrelated factors or only partly attributable to the conflict.Footnote ⁶⁷ As an example, the Panel decided that Syria did not provide sufficient evidence to demonstrate damage to its groundwater resources from pollutants resulting from the oil well fires in Kuwait because “the scarcity of pre-invasion data makes it difficult to assess the full significance of the post-invasion data”.Footnote ⁶⁸

On the one hand, though baseline data is vital for the precise characterization of pre-invasion conditions, the inadequacy of documented baseline information does not necessarily rule out reparation. On one occasion, the UNCC Panel of Commissioners developed an estimate of the amount of damage to or depletion of rangelands, taking account of the limited baseline information about the conditions of the rangeland areas prior to Iraq's invasion and occupation.Footnote ⁶⁹ On the other hand, baseline conditions can be established by reference to publicly available data and external resources. In its response to the Gulf War reparation claims, Iraq's advisory team used data from several studies undertaken in the countries concerned by reputable universities and technical institutes as well as the work of foreign consultants which provided valuable information for establishing baseline oil pollution levels.Footnote ⁷⁰ Also, in the Certain Activities case, the ICJ awarded compensation for environmental damage without clear evidence on reliable baseline data being presented.Footnote ⁷¹ Suggestions have been put forward to seek assistance from scientific experts who are able to palliate the unavailability or insufficiency of data on baseline conditions by using data from reference sites or by means of simulation models.Footnote ⁷²

Establishment of the causal nexus

Establishment of the causal nexus is another challenge facing the assessment of wartime environmental claims. The law of State responsibility requires establishing a link of causality between a culpable act and the damage suffered. The causal link must be “sufficiently direct and certain”, and the damage must be neither too remote nor too speculative.Footnote ⁷³ Realistically, environmental harm may be detected far away from the place where the action was committed, and such physical distance will cast doubt on the causal link between the injury suffered and the wrongful act.Footnote ⁷⁴ In particular, damage to the environment due to armed conflicts may be extensive, spreading far beyond the actual combat zone.Footnote ⁷⁵ In addition, environmental harm is the result of cumulative effects, but providing evidence of causation is often hindered by the multiple and often indirect links between violent conflict and environmental degradation; this problem can be further compounded by the aforementioned absence of baseline data about pre-conflict conditions.Footnote ⁷⁶

Given that the causation between environmental damage and wrongful acts during the conflict is not always clear and straightforward, a strict interpretation of the rules on evidence places a heavy burden on the claimant, particularly with respect to damages resulting from concurrent causes.Footnote ⁷⁷ In this regard, the solution for attaining full reparation is to develop specific causality standards applicable to wartime environmental damage.

As set out by the UNCC, in the case of Iraq's invasion and occupation of Kuwait, regard must be paid to the contribution of any pre-existing or subsequent causes where such causes can be identified, “not in determining the restoration objective to be achieved by remediation, but in determining the proportion of the costs of remediation that can reasonably be attributed to [the invasion]”.Footnote ⁷⁸ The Panel of Commissioners made it plain that Iraq is not exonerated from liability for loss or damage simply because other factors might have contributed to the loss or damage. Evidence present in relation to each head of loss or damage is the basis for ascertaining the existence of a direct causal nexus.Footnote ⁷⁹

In a similar vein, the ICJ elaborated later in the Armed Activities case that the question of causation raises certain difficulties in the situation of a long-standing and large-scale armed conflict, as the causal nexus between the internationally wrongful act and the alleged injury may be “insufficiently direct and certain to call for reparation”.Footnote ⁸⁰ It may be the case that damage is attributable to several concurrent causes, including the acts or omissions of the responsible State; or that several internationally wrongful acts of the same nature, but attributable to different actors, may result in a single injury or several distinct injuries. The Court had to consider these questions as they arose, in light of the facts of the case and the evidence available.Footnote ⁸¹ The Court then made a distinction between the actions and omissions that took place in the area that was under the occupation and effective control of Uganda and those that occurred in other areas not necessarily under Uganda's effective control. As regards the latter, the Court took account of the fact that some of the damage occurred as a result of a combination of actions and omissions attributable to other States and to rebel groups. Nevertheless, the fact that the damage was the result of concurrent causes was not sufficient to exempt Uganda from any obligation to make reparation.Footnote ⁸²

In specifying the legal test for causation, the ICJ highlighted that “the causal nexus required may vary depending on the primary rule violated and the nature and extent of the injury”.Footnote ⁸³ It appears difficult to draw definite conclusions about how the standard of proof regarding the causal nexus correlates with the primary rule violated and the nature and extent of the injury, yet it is undeniable that the existence of concurrent causes does not exempt the responsible actor from the obligation to make reparation for wartime environmental damage. In cases where the causal link is insufficiently direct and certain, the extent of injury attributable to the responsible actor can be assessed in light of the specific factual circumstances and the evidence produced. At the very least, in a situation of occupation, consideration must be given to whether the actor exercised effective control over the territory where the damage occurred.

In addition, the ICJ recognized that pursuant to the rules of attribution, in certain situations a single actor may be required to make full reparation for the damage while in other situations the responsibility should be apportioned among multiple actors.Footnote ⁸⁴ This is consistent with the position taken by the UNCC, which held that due account of the contribution from other factors should be taken in order to determine what proportion of the damage is attributable to the responsible actor.Footnote ⁸⁵ In other words, the level of compensation paid by each actor should be proportionate to the amount of damage contributed by that actor. Note that divergence occurred when evidence did not reflect the proportion of each contribution. The ICJ took into account available evidence in arriving at a global sum awarded for all damage,Footnote ⁸⁶ while the UNCC was of the view that when the proportion of Iraq's participation in the damage could not be accurately proven, it recommended no compensation.Footnote ⁸⁷

Valuation of environmental damage

Valuing environmental losses is a challenging exercise because, on the one hand, restitution is often impossible to achieve, and on the other, the valuation of environmental damage requires special techniques.Footnote ⁸⁹ Notwithstanding its primacy as a form of reparation, restitution is frequently unavailable or inadequate in relation to environmental damage due in large part to the irreversible nature of such damage.Footnote ⁹⁰ In the Gabčíkovo-Nagymaros Project case, the ICJ noted “the often irreversible character of damage to the environment” and “the limitations inherent in the very mechanism of reparation of this type of damage”.Footnote ⁹¹ This is particularly evident in the context of armed conflict. It is often the case that armed conflict causes massive and widespread environmental harm, and restitution is often costly and sometimes impossible in the case of irreversible harm. For general reparations, the ARSIWA describes compensation as “perhaps the most commonly sought in international practice”,Footnote ⁹² while it is also preferred by claimants for environmental harm due to sovereignty concerns. In addition, despite having a non-economic value requiring restoration to the state prior to the damage occurring, pure environmental damage may be incapable of being calculated in market terms. As a result, compensation raises the problem of assessing the quantum of environmental damage – i.e., whether it should be based on the costs of reinstatement measures, on an abstract quantification computed using a theoretical model, or on some other basis.Footnote ⁹³

The legal precedents for international environmental compensation are generally limited, indicating that the rules of international law relating to the valuation of environmental damage remain underdeveloped.Footnote ⁹⁴ In addition to the ICJ and the UNCC, a substantial jurisprudence on awarding compensation has been developed in the practices of various international courts, tribunals, institutions and mechanisms, including the International Tribunal for the Law of the Sea, the International Oil Pollution Compensation (IOPC) regime, the Iran–United States Claims Tribunals, the European Court of Human Rights, the Inter-American Court of Human Rights, and the International Centre for Settlement of Investment Disputes tribunals under the Convention on the Settlement of Investment Disputes between States and Nationals of other States.Footnote ⁹⁵ Notwithstanding that significant body of precedents, the questions of assessment and valuation of environmental damage were under-addressed until recently. Moreover, war reparations are usually settled by agreement between the belligerents,Footnote ⁹⁶ and these agreements do not necessarily conform to the standard of full reparation. In consequence, the customary rules on compensation for environmental losses are less settled, whether in the context of armed conflict or in times of peace.

Loss of ecosystem services

The inherent difficulties in quantifying environmental damage lie in the growing focus on the value of ecosystem services. Developed at an early stage of modern environmental science and law, the law of war did not adequately appreciate the extent and type of harm suffered by the environment during armed conflict.Footnote ⁹⁷ With increased emphasis placed on the concept of “ecosystem services” as well as their intrinsic value, there is now general recognition that conflicts often, directly or indirectly, affect human health and livelihoods as well as ecosystem services,Footnote ⁹⁸ and that durable peace cannot be achieved if the natural resources sustaining livelihoods and ecosystem services are damaged degraded, or destroyed.Footnote ⁹⁹ This view was endorsed by the ICJ in the Certain Activities case. The Court stated that “damage to the environment, and the consequent impairment or loss of the ability of the environment to provide goods and services, is compensable under international law”, and that “such compensation may include indemnification for the impairment or loss of environmental goods and services in the period prior to recovery and payment for the restoration of the damaged environment”.Footnote ¹⁰⁰ These groundbreaking holdings were reinforced in the Armed Activities case.Footnote ¹⁰¹

While efforts to quantify environmental value in financial terms are nearly always imperfect,Footnote ¹⁰² it is now evident that under international law the valuation of environmental damage should include compensation for losses in ecosystem services so that the injured State can be made whole. Although no generally applicable valuation technique is prescribed or prohibited by international law,Footnote ¹⁰³ international judicial institutions have been attempting to quantify the losses to be compensated for damaged ecosystem services, as the practices of the UNCC and the ICJ suggest. The UNCC Panel of Commissioners recommended compensation for a wide variety of environmental damage, while noting the inherent difficulties in attempting to place a monetary value on damaged natural resources, particularly resources that are not traded in the market.Footnote ¹⁰⁴ Notably, in several cases concerning the loss of ecological services, the Panel accepted the claimant's use of methods such as habitat equivalency analysis (HEA) and rejected some other methods such as travel costs surveys for the purpose of determining the nature and extent of compensatory remediation.Footnote ¹⁰⁵ In the Certain Activities case, the proffered methods of both parties were deemed relevant but neither was chosen by the Court; instead, a somewhat opaque method referred to as an “overall valuation approach” was adopted.Footnote ¹⁰⁶ These different approaches to valuation were developed in conformity with the general principles and rules applicable to the determination of compensation, with a view to achieving the goal of full reparation. It should be mentioned that one potential risk involved with addressing reparations only as monetary compensation is the failure to implement environmental recovery measures following the transfer of funds. The risk is even higher if economic techniques, rather than the actual cost of remediation and restoration, are used to value ecosystem services.

The valuation approaches employed by both the UNCC and the ICJ seem to offer only limited guidance for assessing wartime environmental damage. For instance, the UNCC Panel's application of HEA in a number of claims demonstrates a valuation procedure for ecosystem services that can be employed in future proceedings to protect and restore ecological services that are not traded in the market;Footnote ¹⁰⁷ however, it is noted that HEA is used most effectively in oil spill cases, particularly those limited in spatial extent, but long-term environmental harm which spans multiple decades can be very difficult to evaluate using HEA.Footnote ¹⁰⁸ In its overall valuation in the Certain Activities case, the ICJ was keen to adopt an approach that accounted for the correlation between the most significant damage to the area and other harms, the specific characteristics of the area, and the capacity of the damaged area for natural regeneration.Footnote ¹⁰⁹ These considerations appear to offer a useful starting point in choosing the methods used to quantify wartime environmental damage, but the absence of an explanation as to when such a method (or any other alternatives) can be an effective tool for estimating losses in ecological services or how such a method should be conducted makes it not easily replicable for subsequent environmental cases. Hence, while there is no one-size-fits-all approach to the valuation of environmental damage, it is meaningful to form certain quantitative guidelines for how to compute the losses that are recoverable in order to ensure consistency in choosing the methods of calculating the amount of compensation.

Environment-related damage to public health

As a further complication, the valuation of damages to public health that are the result of armed conflict poses unique challenges. The environment affects the right of living: the fundamental importance of the right to a safe, clean, healthy and sustainable environment has been recognized at the international level,Footnote ¹¹⁰ and large-scale environmental damage exerts influence on a huge but uncertain number of populations during and after an armed conflict. Reference can be made to the Environmental Guidelines published by the Office of the UN High Commissioner for Refugees (UNHCR), which note that “the state of the environment … will have a direct bearing on the welfare and well-being of people living in that vicinity, whether refugees, returnees or local communities”.Footnote ¹¹¹

Full reparation for wartime environmental damage cannot lose sight of the health and quality of life of the population. Ultimately, the relationship between reparation for the environment and for the well-being of humankind is not incompatible but symbiotic.Footnote ¹¹² Underpinning the law of armed conflict, as well as international environmental law and human rights law, the two incentives often go hand in hand.Footnote ¹¹³ In the UNCC proceedings, several claimant governments submitted substantive compensation claims for public health damage associated with the environmental damage caused by Iraq. The scope of the claims covers, for example, fatalities or increased mortality in the country as a result of exposure to air pollution during the invasion and occupation,Footnote ¹¹⁴ costs of medical treatment of an increased number of diseases attributed to exposure to air pollutants,Footnote ¹¹⁵ and treatment costs and loss of well-being associated with post-traumatic stress disorder and other psychiatric illnesses.Footnote ¹¹⁶ The Panel of Commissioners concluded that public health damage is compensable in principle, and that the test to be applied is whether the expense or loss for which compensation is claimed has actually occurred and can reasonably be demonstrated to be a direct result of Iraq's invasion and occupation of Kuwait.Footnote ¹¹⁷ However, in the majority of the health-related cases, the Panel found that the evidence submitted did not provide a sufficient basis for determining the extent to which the effects of the oil well fires might have contributed to the damage, or in other words, whether or what proportion of the damage, if any, can reasonably be attributed to the effects of the oil well fires or to Iraq's invasion and occupation. In the end, less than 0.1% of the amount claimed for substantive public health damages was granted.Footnote ¹¹⁸

The frequent failure of claimant governments to meet evidentiary standards for compensation highlights the necessity of equitable considerations. Referring to the approach adopted in the Diallo Footnote ¹¹⁹ and Trail Smelter Footnote ¹²⁰ cases, the ICJ underlined that “the absence of adequate evidence as to the extent of material damage will not, in all situations, preclude an award of compensation for that damage”.Footnote ¹²¹ Rather,

Given the uncertainties of health-related effects relating to environmental damage in the context of armed conflict, the amounts of compensation can be assessed on an equitable basis which is commensurate with the scale of the relevant damage. In the meantime, special care should be taken to ensure that compensation determined on the basis of equitable considerations excludes the possibility of being “punitive or exemplary”.Footnote ¹²³