Mineralogy of selected geological deposits from the United Kingdom and the Republic of Ireland as possible capping materials for low-level radioactive waste disposal facilities

Solid low-level radioactive waste (LLW) is currently being disposed at a number of facilities in the United Kingdom (UK). The safety of these facilities relies to some extent on the use of engineered barriers, such as a cap, to isolate the waste and protect the environment. Generally, the material used as the barrier layer within such a cap should be of low permeability and it should retain this property over long timescales (beyond a few decades normally required for facilities containing non-radioactive wastes). The objective of this research is to determine the mineralogy of selected geological deposits from the UK and Ireland as part of a larger project to examine their suitability as a capping material, particularly on LLW sites. Mineral transformations, as a result of future climate change, may impact on the long-term performance of the cap and even the disposal facility. X-ray diffraction (XRD) was carried-out on the sand, silt and clay fractions of the London Clay, Belfast Upper Boulder Clay, Irish Glacial Till, Belfast Sleech, and Ampthill Clay geological deposits. Minerals were present that could pose both positive and negative effects on the long-term performance of the cap. Smectite, which has a high shrink swell potential, may produce cracks in London Clay, Belfast Upper Boulder Clay and Ampthill Clay capping material during dry, hotter periods as a possible consequence of future climate change; thus, resulting in higher permeability. Ampthill Clay and Belfast Sleech had elevated amounts of organic matter (OM) at 5.93% and 5.88%, respectively, which may also contribute to cracking. Over time, this OM may decompose and result in increased permeability. Gypsum (CaSO4) in the silt and sand fractions of Ampthill Clay may reduce the impact of erosion during wetter periods if it is incorporated into the upper portion of the cap. There are potential negative effects from the acidity created by the weathering of pyrite (FeS2) present in the silt and sand fractions of Belfast Sleech and Ampthill Clay that could impede the growth of grasses used to stabilize the surface of the capping material if this material is used as part of the vegetative soil layer. Additionally, acidic waters generated from pyrite weathering could negatively impact the lower lying capping layers and the disposal facility in general. However, the calcium carbonate (CaCO3) present in the silt and sand fractions of these deposits, and dolomite (CaMg(CO3)2) in Belfast Sleech, may counter act the acidity.

'Democratic Transition, Judicial Accountability and Judicialisation of Politics in Africa: The Nigerian Experience'

Purpose – This paper aims to examine the growing incidence of judicialisation of politics in Nigeria’s democratisation experience against the backdrop of questionable judicial accountability. Design/methodology/approach – The article draws on legal and political theory as well as comparative law perspectives. Findings – The judiciary faces a daunting task in deepening democracy and (re) instituting the rule of law. The formidable challenges derive in part from structural problems within the judiciary, deficient accountability credentials and the complexities of a troubled transition. Practical implications – Effective judicial mediation of political transition requires a transformed and accountable judiciary. Originality/value – The article calls attention to the need for judicial accountability as a cardinal and integral part of political transitions. Keywords Democracy, Politics, Law, Nigeria, Africa Paper type Viewpoint

'Robes on Tight Ropes: The Judicialisation of Politics in Nigeria'

This account of judicialised politics in the Nigerian transition experience examines the regulation of the judiciary of the political space, through the resolution of intergovernmental contestations in a dysfunctional federation. It analyses the judicialisation of elite power disputes which have resonance for due process and the rule of law in particular and governance in general. A study of the role of the judiciary in stabilising the country, itself a pivot in the West Africa region in particular and Africa in general, is important. This is especially in view of its classification as a ‘weak state,’ despite its enormous human and natural resources. The analyses here suggest the Supreme Court has taken a strategic position in the task of democratic institutional building and the reinstitution of the rule of law in the country. This strategic measure has received the acclaim of the public. However, the account also discloses that the judiciary, in the course of its numerous interventions, has been drawn into overly political disputes that overreach its jurisprudential preferences. Of even more significance, it demonstrates that the judiciary is itself still challenged by institutional dysfunctions constituting part of the legacies of the authoritarian era. The situation leads back to the need for closer scrutiny of the judicial function in transitional societies.

‘Risk, Politics and the ‘Scientification’ of Political Judgement: Prisoner Release and Conflict Transformation in Northern Ireland’

Drawing on research in Northern Ireland into the process of release under the Belfast/Good Friday Agreement, this article explores the identification and classification of risk in relation to prisoners released early under the Sentences (NI) Act. The main argument is that conflict, post-conflict and transitional conditions expose more starkly the political underpinnings of risk-management strategy and the article demonstrates the particular variant of Politicized Risk Assessment (PRA) recently used in the release of prisoners in Northern Ireland