Background: In response to a need identified by the Scottish Environment Protection Agency (SEPA) and Scottish Natural Heritage (SNH), a Working Group was set up by Construction Scotland Innovation Centre in the course of 2015/16 comprising of parties in the public, academic and business sectors who had an interest in exploring the options for the infrastructure surrounding end-of-life-cycle wind turbines, in particular the concrete wind turbine bases. The setting up of this Working Group was Phase 1 of this project (now complete) and the report of this working group constitutes Phase 2 (2017/18) of the project. Repowering is the implementation of measures to extend the life of components and turbines at wind farm sites, or the replacing and replanting existing turbines. Current established practice when repowering wind turbines within an existing wind farm is to replace the turbine with a new concrete base and not re-use existing foundations. This is a fresh capital expense, and the environmental impact and sustainability of this is unknown, generating concerns that need answers such as can concrete foundations be reused to reduce the excavation of peat and the generation of carbon emissions. Prof. Susan Waldron from the University of Glasgow, and Prof. Jo. Smith from the University of Aberdeen were commissioned to undertake research to assess the environmental considerations of wind farm repowering. Both have 10+ years of experience of considering windfarms and the environment. Their research was in conjunction with engineering input from Arup, commercial input from SSE and SPN and consultation with manufacturers through Scottish Enterprise. This resultant report identified for the Working Group the beneficial and detrimental effects that may arise if concrete wind turbine bases are removed, or conversely, are re-powered. The academic element of the project focussed on ecological, hydrological, biogeochemical and C security impacts, and considered if these processes are captured in the Scottish Government’s ‘Carbon Assessment Tool’, used primarily in wind farm approval planning. The final report is a research report and not a policy document. Further, industry and regulator participation does not mean they endorse the conclusions or recommendation and thus final responsibility for the contact rests with the lead academic author: Prof. Susan Waldron. However, those responsible for the development of practice and policy in Scotland in relation to Wind Farm Developments will use this report for example in considering the development of “best practice” options for future wind turbine installations, or to explore the nature of product development in relation to wind turbine foundations.