Platform for Long-term Experimental Investigation of Alteration in Disposal Environments and Storage - PLEIADES

昂宿星团将建立必要的研究基础设施，以支持为遗留、新建造和未来核燃料循环产生的无线电材料制定退役、临时储存和处置安全案例。它将使与核能有关的政府政策的3个关键领域能够进行研究：1.地质处置：英国政府的核退役责任及其未来新建雄心的成功取决于成功执行提供放射性废物地质处置设施(GDF)的政策。有必要证明，在建造GDF之前，关闭后的安全将得到维护。这需要了解垃圾在GDF条件下的长期腐蚀率和降解机制，而昂宿星团将处于独特的位置来提供这些信息。2.减少遗留核设施的危险：英国核遗产退役的风险和危险是世界上最具挑战性的。在退役期间，放射性废物被转化为一种可以安全储存数十年的形式。在储存过程中，废物不应改变或降解，但有许多是容易腐蚀的。昂宿星团内的设备将有能力确定这类放射性材料的腐蚀过程和速率，告知临时储存的安全案例，以及随后关于未来管理实践的决定。加快核退役：最近宣布，到2030年，为英国纳税人节省1200亿GB的核退役成本20%的首选解决方案是开发至少一个近地表处置(NSD)设施。在NSD中处置废物可以大大缩短退役时间。这一新方法成功的关键是对NSD安全性的评估，包括100多年处置过程中放射性废物降解的模型。昂宿星团有能力解决此类设施中废物的腐蚀和放射性核素释放率方面的关键知识空白，从而支持加速实施NSD。PLEIADES将是英国唯一的设施，能够进行研究，解决学术界和放射性废物管理行业确定的能力方面的关键差距：地下处置条件下的腐蚀：由于放射性材料对大气条件高度敏感，因此至关重要的是在实验室中复制地下处置环境。只有在腐蚀实验过程中保持正确的条件，才能获得有意义的数据。昂宿星团的设备将能够对广泛的放射性材料进行这样的研究，因为目前英国没有这种能力。&gt；长期腐蚀：昂宿星团的一个独特方面是能够在代表地下环境的稳定条件下建立长期(数十年)腐蚀实验，提供对缓慢降解过程的详细洞察。距离建造GDF还有不到20年的时间，如果我们想要理解放射性废物腐蚀背后的科学，现在建立长期实验是必不可少的。辐射场中的腐蚀：放射性材料的腐蚀过程可能会受到辐射效应的显著影响。目前人们对这些影响知之甚少，因为支持他们进行调查的设施很少。昂宿星团将构成英国唯一的大学设施，能够分析产生自己辐射场的高放射性材料，昂宿星团设备将与其他用户设施兼容，使腐蚀实验能够在外部辐射场内进行。

PLEIADES will establish essential research infrastructure to underpin the development of decommissioning, interim storage and disposal safety cases for radio-materials arising from legacy, new build and future nuclear fuel cycles. It will enable research in 3 key areas of government policy relating to nuclear energy:1. Geological disposal: The success of HM Government's nuclear decommissioning responsibilities and its future new build ambitions rests upon the successful implementation of policy to deliver a geological disposal facility (GDF) for radioactive waste. It is necessary to demonstrate that post-closure safety of a GDF will be maintained before it can be built. This requires an understanding of long-term corrosion rates and degradation mechanisms of waste, under GDF conditions, which PLEIADES will be uniquely placed to provide. 2. Reduce hazard of legacy nuclear sites: The risks and hazards of decommissioning the UK's nuclear legacy are the most challenging in the world. During decommissioning, radioactive wastes are converted into a form that can be safely stored for many decades. During storage, the waste materials should not change or degrade, however, there are many that are subject to corrosion. The equipment within PLEIADES will have the capability to determine the corrosion processes and rates of such radio-materials, informing safety cases for interim storage and subsequent decisions about future management practice.3. Accelerate nuclear decommissioning: It was recently announced that the preferred solution to deliver savings of 20% in the £120 billion cost of nuclear decommissioning to the UK taxpayer, by 2030, is the development of at least one Near Surface Disposal (NSD) facility. Disposal of waste in NSD could dramatically reduce decommissioning timescales. Pivotal to its success of this new approach is an appraisal of NSD safety, including models of radioactive waste degradation over the 100s of years of disposal. PLEIADES has the capability to address critical knowledge gaps in corrosion and radionuclide release rates from waste in such facilities and, therefore, to support accelerated implementation of NSD.PLEIADES will be a unique facility in the UK, enabling research that addresses key gaps in capability that were identified by the academic community and radioactive waste management industry: > Corrosion in sub-surface disposal conditions: Because radio-materials are highly sensitive to atmospheric conditions it is essential that sub-surface disposal environments are replicated in the laboratory. Only if the correct conditions are maintained during corrosion experiments will meaningful data be obtained. The PLEIADES equipment will enable such research on a wide range of radio-materials, for which is there is no current UK capability.> Long-term corrosion: A unique aspect of PLEIADES is the capability to establish long-term (decades) corrosion experiments under stable conditions representative of sub-surface environments, giving detailed insight to slow degradation processes. With less than 20y remaining until a GDF will be constructed, the establishment of long-term experiments is essential now, if we are to understand the science behind radioactive waste corrosion.> Corrosion within a radiation field: Corrosion processes of radio-materials can be significantly influenced by the effects of radiation. These effects are currently poorly understood because there is a paucity of facilities that enable their investigation. PLEIADES will constitute the only UK university facility with capability for analysing highly radioactive materials that create their own radiation field, and the PLEIADES equipment is compatible other user facilities that will enable corrosion experiments to be performed within an external radiation field.