Richard Collins

INTRUSION MODELLING AND THE EFFECT OF GROUND WATER CONDITIONS

Intrusion of contaminants into water distribution systems due to negative pressures is a complex phenomena that has been theorised and is an active area of research. Work has identified the existence of contaminants in soil and ground water surrounding pipes, and has investigated modelling the risk to human health should contaminants enter water distribution systems. However, there is a lack of understanding regarding the critical interaction between the pipe, the leak aperture and the surrounding ground and water. Typical intrusion models assume a simple orifice relationship, with inflow volumes proportional to the square root of the difference between the pipe pressure and the external hydrostatic pressure. This is shown here through computational modelling to be an overly simple relationship for leak behaviour that does not take into account the existence or properties of a porous media external to the pipe. In this paper the authors will discuss the construction of computational fluid dynamics (CFD) models of the intrusion process due to transient events and describe results that suggest the simple orifice equation is not a sufficient model. In the CFD calculations the surrounding ground water is modelled as a saturated porous media and it is shown that the properties of the media and the leak geometry have a large effect on the relationship between the pressures and flow rate. It is also shown that the risk of intrusion should be considered from contaminants that originate from both above and below the depth of the pipe. Further, the idea of a zone of influence surrounding the leak point, due to the leak size and the magnitude and duration of the negative pressure, is introduced as a possible measure of the level of risk of the intrusion event.

Movements in an Irish mute swan Cygnus olor population

Mute Swans ringed in Dublin made shorter movements in the six months after fledging than in their second year. Mobility declined as swans got older. Most movements began or ended in flocks and the distances travelled reflected flock separations. Swans moved greater distances than recorded in Britain.

The Rule of Law and the Quest for Constitutional Substitutes in International Law

The practice of modern international law seems inherently bound up with the quest for a rule of law in international affairs. This commitment to the rule of law at the international level finds expression not merely in academic literature, but has been regularly endorsed by states themselves, particularly in the context of the United Nations. Nevertheless, the pursuit of an international rule of law is an ambition which is constantly frustrated. The institutional structure of the international legal order seems incompatible with this vision, resulting in a constant sense of frustration about the apparently ‘primitive’ or otherwise constitutionally deficient institutional structure of modern international law. In fact, despite the intensification of ‘governance’ through international institutions in the years since the end of the Second World War, it seems like the proliferation and growing normative authority of international institutions more often than not gives rise to more concerns from a rule of law perspective. In this article I not only seek to understand the nature of this rule of law commitment and the reasons for this constant frustration, but in doing so I will argue that the institutional context implicit in the ideal of the rule of law is incompatible with the nature and functioning of international law. I seek to show, in fact, how the perpetual sense of frustration felt in international law’s failure to live up to this ideal stems from the fact that the rule of law is a notion which is implicitly bound up with the political context of sovereign authority within states. To attempt to impose the rule of law outside of this context will not only result in distortion and mischaracterisation, but runs the risk also of legitimising precisely the kind of arbitrary authority which is the main target of the rule of law itself.

The problematic concept of the international legal official

The concept of the ‘legal official’ is one of the most under-theorised yet critical explanatory elements of modern analytical jurisprudence. However, it is also a term beset by conceptual uncertainty and functional ambiguity. In fact, as commonly employed by analytical theorists, it seems to function merely as a boot-strapping device, relinquishing the need to justify the kind of pre-legal hierarchy or constitutional authority commonly found at the state level. This reliance on officialdom is particularly problematic bearing in mind that the lack of any such hierarchies at the international level has been the cause of constant scepticism as to the reality and efficacy of international law as a legal system. Recognising the specific functional benefits which officials bring to the task of law within the state, however, offers up two methodological conclusions: first, that the theorist cannot simply presume, a priori, that legal officials are necessary without a coherent normative defence of the perceived functions of law upon which this justification stands; and secondly, that any view of laws function and important institutional features must still be informed by a more genuinely global empiricism.

Doing law beyond the state: Methodological questions in international and transnational legal theory

Over the last two decades the landscape of legal theory has changed dramatically. Well-established assumptions regarding the nature of law have been cast into doubt by a notable expansion in the normative scope and regulative reach of forms of law beyond the state. This has resulted in two distinct, but related, disciplinary shifts. First, analytical legal theory has begun to question seriously its parochial focus, turning its gaze towards global or international legal phenomena. Secondly, international and European lawyers are beginning to revisit conceptual questions about the nature of their respective fields as conventional disciplinary certainties vanish from view. Whilst these shifts have prompted disciplinary self-reflection, a cross-disciplinary dialogue has not yet been well-established. Where legal philosophers have begun to wonder how EU, international and transnational legal phenomena impact on the concept of law, these enquiries are still very much embryonic and often disconnected from the more practical concerns of international and EU lawyers. At the same time, it is clear that international and EU lawyers reflect more on the theory of their discipline than they used to, but there have been relatively few cross-disciplinary conversations about the nature of law, or ‘legality’ in general. It is against this background that this special edition of Transnational Legal Theory took shape. The papers in this issue arose out of a workshop at the University of Bristol in January 2014, which was organised by the editors of this special edition. The workshop included contributions by Cormac Mac Amhlaigh (Edinburgh), Jean d’Aspremont (Manchester/Amsterdam), Julie Dickson (Oxford), Jörg Kammerhofer (Freiburg), Michael Giudice (York, Canada), Gleider Hernandez (Durham), Jacob v H Holtermann (Copenhagen), Anne van Mulligen (Amsterdam), Henrik Palmer Olsen (Copenhagen), Stuart Toddington (Huddersfield), Ingo Venzke (Amsterdam), Wouter Werner (VU Amsterdam) and

No Longer at the Vanishing Point? International Law and the Analytical Tradition in Jurisprudence

The emergence of ‘modern’ international law has an inseparable, yet uneasy connection to the analytical tradition in jurisprudence. In fact, one of the first proponents of the analytical method, Jeremy Bentham, is credited with coining the term ‘international law’, as he sought to differentiate the positive legal relations actually pertaining between states from the older, more philosophical tradition of the ‘Law of Nations’.1 The waning of this older conception of the Law of Nations, rooted in natural law, and the slow acceptance that international law was an institutional practice similar in nature—if, importantly, not in structure—to the practice of state law, marks out the beginnings of the modern discipline familiar to many today. For as long as it has been thought of in this way, however, international lawyers have struggled to provide a convincing explanation of international law understood as a system of positive legal rules. Analytical legal philosophers since and including Bentham—from John Austin to HLA Hart—have been highly sceptical about the ontological reality of international law conceived as an autonomous legal order in this sense. This long-standing scepticism has, over the years, led to a noticeable disengagement between the two disciplines: on the one hand, international lawyers seemingly absorbing a sense of deficiency or ‘primitiveness’ in relation to the institutional condition of international law; and on the other, contemporary analytical legal philosophers therefore almost entirely marginalising international law as a worthy object of theoretical study. Nevertheless, in recent years, partly as a result of internal disciplinary critique, and partly in response to more existential anxieties caused by the proliferation and growing normative authority of international legal regimes and institutions, it seems