Historically the UK implemented a "nominal" twice-through cycle whereby used nuclear fuels were reprocessed, but uranium and plutonium were not recycled: they were stored pending a future decision by the UK Government. However, the policy for managing higher activity wastes is clear: it envisages their disposal in a Geological Disposal Facility. Consultations for siting a repository which were suspended in 2013 have recently restarted, but the repository will not be available for several decades at the earliest. This article presents a comprehensive LCA study on the historical UK approach for managing used nuclear fuels and the UK Government policy for disposal of higher activity wastes. The underpinning purpose is to inform policy and decision-makers concerned with decisions on the future of the UK nuclear fuel cycle. The study relies on a combination of operational data from the Sellafield site - the industrial complex home to the UK reprocessing plants and literature data on the GDF, and on a number of assumptions regarding the GDF design and disposal of higher activity wastes. The results reveal that a great proportion of the environmental impacts can be linked to two specific causes: indirect burdens from production of uranyl nitrate, which is used to separate plutonium from uranium, and copper, proposed in one scenario to be used as the outer layer of the disposal canister for High Level Waste. The results also demonstrate that the carbon intensity of the management of used nuclear fuels is practically negligible when compared with results from other LCA studies that cover the entire fuel cycle. (c) 2020 Elsevier B.V. All rights reserved.