Work was undertaken to define the scope of the studies that will make up the project’s EIA. This is a series of assessments of the potential effects of a proposed project on the receiving environment, undertaken by specialist and technical consultants. Assessments have been completed for the following topics.
Landscape and visual
A landscape and visual impact assessment has been undertaken to identify the landscape and visual receptors in relation to the proposed project, as well as the potential impacts the project may have on the physical elements of the landscape. Areas included in the assessment are landscape character, designated scenic and landscape areas, Wild Land Areas and viewpoints from various locations such as settlements, routes, hill tops and other sensitive locations.
Hydrology and hydrogeology
Hydrological and hydrogeological aspects were a key component in the design process and proposed layout; it is essential with any development to reduce the risk of hydrological impacts as much as possible, including pollution, flood potential and acidification.
Desk-based studies, consultation and site walkovers have been conducted to establish the potential effects of the proposed project on both hydrological and hydrogeological features, such as the River Thurso and the Little River, as well as other waterbodies in and around the site.
A site walkover was conducted in July 2020 to visually inspect surface water features, obtain an understanding of the local topography and drainage patterns and to confirm the information reviewed and collated in the desk-based assessment.
Consultation with SEPA and Scottish Water has supported a thorough assessment of the area and the potential effects of the project.
Peat and ground conditions
Avoiding deep peat was a crucial driver of the design process, and the proposed layout seeks to avoid disturbance to these nationally important carbon stores. The EIA presents a Peat Management Plan which details peat depths across the site. A Carbon Balance Assessment has also been undertaken that details the overall carbon losses and savings as a result of the development, as well as the estimated carbon payback period. The shorter the payback period, the greater benefit the project will have in displacing emissions associated with electricity generated by burning fossil fuels.
Ecology
Surveys have been carried out to determine the presence of ecology and habitats on and around the site. This included surveys for vegetation, bats, wildcats, fisheries and other protected species such as otter, badger, pine marten, water vole and reptiles. The EIA has assessed the impacts of the project on these species in terms of effects such as habitat loss and disturbance, potential displacement, turbine-related bat mortality.
Ornithology
Surveys began in September 2018 and concluded in August 2020, to determine the presence of ornithology and habitats on and around the site. This included flight activity surveys, foraging goose and swan surveys, upland breeding bird surveys, breeding raptor surveys and breeding diver surveys. The EIA assessed the impacts of the project on these species in terms of effects such as disturbance, habitat loss and potential displacement.
Noise
Turbine technology is constantly improving so that turbines are more efficient than in the past with updated noise control technology systems. The control systems of all modern wind turbine models are capable of controlling the noise emissions from the turbines through management of factors such as rotational speed and blade pitch. It will therefore be possible to manage the noise emissions of the project to ensure compliance with appropriate noise limits.
Extensive and detailed modelling exercises were undertaken for the various layout iterations to determine the appropriate noise levels that would be required for the operation of the wind farm to adhere with ETSU noise limits.
An assessment on the effect of noise on human receptors, including residential properties and villages in close proximity to the site, by comparing the noise levels of the development against existing background noise levels, is presented in the EIA Report.
Archaeology and cultural heritage
The cultural heritage assessment considers potential effects on known designations within proximity of the project. There are no nationally designated assets within the site, although there are Scheduled Monuments located close to the site boundary.
A heritage walkover and site setting visit has been undertaken where our cultural heritage specialist augmented data gathered from records and highlighted through the scoping responses, and determined whether previously unrecorded historic features are visible.
The project layout and design has sought to avoid direct effects on heritage assets on site and minimise indirect effects to assets surrounding the site. The effects of the project on these assets have been assessed within the EIA Report. Where any significant effects have been identified, appropriate mitigation is recommended.
Access and transportation
The assessment considers all routes which are likely to be used by project construction traffic and focuses upon the movement of traffic along the public road network including abnormal load vehicles (turbine components) and construction related traffic (heavy and light goods vehicles and cars).
The port for delivery of wind turbine components is anticipated to be Wick, and the focus of the assessment has therefore been on the A99, A9, B870 and the unnamed road towards Altnabreac.
The assessment includes potential effects arising from traffic generation as a result of the construction period, such as pedestrian amenity, accidents and safety, driver delay and noise.
Socio-economics, including tourism, recreation and land use
The assessment consists of a desk-based study whereby the impacts on socio-economic features such as employment and the economy has been assessed. The desk-based study also assesses the impacts on tourism, recreation and land-use features such as the core path and walkway – Caithness A – which has a number of routes in and around the site, as well as any national cycling networks. The River Thurso which is a popular salmon angling river is also considered. Impacts on hotels and local accommodation, such as the Ulbster Arms Hotel, and recreational activities and tourist attractions, such as Achalone Activities and Achanarras Quarry, are included in the assessment. Consultation with the relevant public bodies and organisations has been conducted.
Aviation and telecommunications
The development of wind turbines has the potential to cause adverse effects on aviation, radar and telecommunications during turbine operation. The assessment into potential effects the wind farm may have on such aspects consisted of a desk-based study to identify the aviation, radar and telecommunication features within and around the site boundary. Consultation with the relevant aviation consultees, including the Ministry of Defence, NATS and Highlands and Islands Airport, and telecommunications consultees, including BT and JRC, has also been completed.
Other considerations, such as shadow flicker
Shadow flicker is an effect that can occur when the shadow of a blade passes over a small opening (such as a window), briefly reducing the intensity of light within the room, and causing a flickering to be perceived. This is dependent on the position of the sun in relation to the wind turbines, and changes based on the time of day. An assessment has been undertaken to determine whether or not there will be any shadow flicker impacts on surrounding properties and the results of the assessment are presented in the EIA Report.
