Abstract
Background
In 2010 Scottish Natural Heritage (SNH) published guidance on Good practice during wind farm construction (GPDWC). The GPDWC guidance is aimed at: wind farm developers, construction companies and contractors working on wind farm sites; consultants and advisors supporting the wind farm industry; planning officers working on wind farm applications; statutory consultees such as SNH, Scottish Environment Protection Agency (SEPA) and others with an interest in wind farm construction, and those responsible for the regulation of wind farms under relevant environmental protection and pollution prevention legislation and environmental / ecological clerks of works.
SNH intends to add to GPDWC with a chapter on Restoration and Decommissioning Plans (RDPs) for onshore wind farms. SLR Consulting Ltd (SLR) was commissioned by SNH to undertake background research to further develop our understanding of the environmental impacts and considerations for restoration and decommissioning to support this new guidance.
Main findings
- There is a willingness and enthusiasm amongst stakeholders to consider the issues of restoration and decommissioning in more depth than has been historically the case.
- There is recognition that by doing so the process of designing and constructing wind farms could be improved.
- It is acknowledged that earlier consideration and regular review of RDPs would be beneficial to the environment.
- There are existing processes where restoration and decommissioning plans could be effectively integrated (Habitat Management Plans, Health and Safety Plans, Construction Method Statement, Construction and Environmental Management Plan).
- There is interest in a step-by-step guide that would provide framework for site by site consideration whilst promoting consistency of approach.
- The planning and/or environmental statement needs to contain sufficient information regarding the likely options for decommissioning and their associated impacts so that this becomes an integral part of the process.
- Technological advances and changes in preferred approaches during the lifetime of a wind farm could mean it would be best practice not to limit options too far in advance of actual decommissioning but to maintain informed flexibility until close to the end-of-life of the wind farm.
- Future planning, beyond the first round of decommissioning and re-powering, and learning from previous experiences to influence good practice is essential.
- A thorough understanding of a site’s natural heritage characteristics (its setting and relationship with surrounding area) and how these respond to change is critical to assess how the impacts of elements of the decommissioning strategy (e.g. construction works, habitat restoration, ground stability etc.) might affect the site. Only with this understanding can the decommissioning strategy be determined and appropriate mitigation measures identified.
- RDPs recommendations for infrastructure removal should reflect techniques and approaches that will result in the least disturbance to the environment, subject to the wider aims of the decommissioning strategy.
- From a landscape and visual perspective any demolition and reinstatement should achieve the greatest improvements with the least disturbance and impacts on landscape fabric, character or visual amenity of neighbouring receptors through careful control of the works.
- It is important to understand a site’s soils and their influence on habitats so that reestablished communities are likely to sustain themselves in the long term. The mass balance of soil movement, risk of contamination and avoidance of generating waste soil is critical to sustaining the site appropriately in the long term.
- HMPs need to be proportionate to the site, its ecological interest and the development’s impacts, and expectations of their extent and content, even at the repowering stage, need to be reasonable.
- The RDP should not presume that all positive habitat management works will cease following decommissioning of the wind farm.