Academic journal article Texas International Law Journal

The MOX Plant Case: The Question of "Supplemental Jurisdiction" for International Environmental Claims under UNCLOS

Academic journal article Texas International Law Journal

The MOX Plant Case: The Question of "Supplemental Jurisdiction" for International Environmental Claims under UNCLOS

Article excerpt


The case of Ireland v. United Kingdom,1 currently underway at the Permanent Court of Arbitration in The Hague, raises interesting questions of jurisdiction and applicable law for international environmental claims under the United Nations Convention on the Law of the Sea (UNCLOS, or the Convention).2

In this dispute concerning radioactive waste pollution in the Irish Sea produced by an English nuclear fuel reprocessing facility, Ireland argues that certain UNCLOS provisions allow Convention tribunals to enforce not only UNCLOS directives, but "other rules of international law not incompatible with this Convention" as well.3 As a result, Ireland's claim draws not only from UNCLOS, but also from more than twenty additional international agreements and instruments to which the United Kingdom may be bound." In response, the United Kingdom argues that UNCLOS provides no such jurisdiction to the Tribunal, and as such, the basis for much of Ireland's suit is improper.5

The theory advanced by Ireland in many ways resembles the practice of supplemental jurisdiction as developed in American case law and legislation, which permits the attachment of non-federal claims to valid federal claims when they are all part of the same case or controversy.6 Properly speaking, there is no international law concept analogous to supplemental jurisdiction in U.S. federal law; however, the parallels are striking in this case and will be explored in an effort to understand how such an approach might be understood within the context of UNCLOS.

If the Tribunal permits a kind of supplemental jurisdiction for Ireland's non-UNCLOS claims, the decision could have far-reaching implications for future litigation under UNCLOS, significantly expanding the power of a Convention already considered "the strongest comprehensive environmental treaty now in existence or likely to emerge for quite some time."7 Conversely, a rejection of supplemental jurisdiction could limit similar suits to claims deriving strictly from UNCLOS, which provides powerful dispute resolution procedures but largely conceptual rights and obligations.

As this is a question of first impression for an UNCLOS Tribunal in a case that is, at the time of this writing, still in progress, and as UNCLOS Tribunals possess wide latitude in determining their jurisdiction and applicable law,8 it is not possible to predict which view the court is likely to endorse. With that caveat, it is nevertheless possible to show that the Convention's language, its negotiating history, the customary rules of treaty interpretation, general scholarly commentary, and a comparison with U.S. federal practice lend support to Ireland's "supplemental" approach.


A. Introduction

This case concerns a mixed oxide fuel plant (MOX Plant) in Sellafield, England, on the eastern shores of the Irish Sea.9 Mixed oxide or "MOX" is a nuclear fuel-produced by reprocessing spent nuclear waste-that can itself be used by nuclear power plants for energy production.10 A decision by the British government in 2001 opened the way for commissioning and operation of the MOX plant in question here, which Ireland claims will both directly and indirectly cause radioactive wastes to be discharged into the Irish Sea."

B. The Irish Sea

"The most radioactive sea in the world'

Radioactive waste is of concern regardless of its location, but such pollutants are especially troubling in the Irish Sea, the body of water separating Ireland from the United Kingdom. The Irish Sea is a semi-enclosed sea connected with the Atlantic Ocean by two narrow channels to the north and south.13 These limited inlets, the relatively constrained movement of water to and from the Sea, and the pronounced gyre effect within the Sea "reduce[ ] the effective amount of water for dilution . . . and tend[ ] to cause elevated levels of radionuclides [released into the Sea] to be drawn towards the vicinity of the western Irish Sea gyre," along the eastern coast of Ireland. …

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