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3. ASSESSMENT FINDINGS

3.1 This section of the report provides a summary of the key findings from the assessment.

Structure

3.3 The following paragraphs set out the key findings from the assessment of environmental effects of the RAP. The findings are structured as follows:

1. a summary of the content of the RAP in relation to the delivery of the renewable heat target and biodiversity, identifying key parts that require further consideration.

2. for each environmental topic the following information is provided:

• A brief recap on the relevant baseline information.
• A summary of the predicted environmental effect of the renewable heat target. These are highlighted in amber and green, to denote negative, and positive effects respectively. Where effects are neutral, no colour coding has been applied. Where identified, this part of the report includes details of any significant cumulative and synergistic effects arising from the renewable heat target.
• Identification of any mitigation measures required to address the identified significant effects of the plan.

3. A mitigation schedule which brings together the measures proposed for each of the environmental topic areas and highlights where action is required to ensure implementation of policy safeguards.

4. A proposed framework for monitoring the RAP, focusing on its potential environmental effects.

Summary of the proposals for renewable heat

3.4 The RAP includes a broad aspiration to generate 11% of heat from renewable sources. This represents a significant expansion in the contribution of this sector to energy production, from an estimated 1.4% at present. Around 2.1 GW of installed capacity will be required to achieve the 11% target: developments which are already being constructed could increase the current output to around 2.7% and other proposals which are currently planned could bring the total to around 4.6% of the projected 2020 demand. Of the consultees who responded to the Renewable Energy Framework ( REF), views on the appropriateness of the target varied. Some suggested that this was ambitious and that a major shift will be required to meet it. Others suggested a higher target, with some proposing that this could compensate for shortfalls in other sectors.

3.5 Further detail on how the remaining increase in output will be achieved is provided in a more detailed Renewable Heat Routemap, which is appended to the RAP. The Routemap sets out an overall vision of building a commercially viable, diverse, renewable heat industry. The 'headline ambitions' within the plan are firstly to have renewable heat as a first choice within areas which are off the gas grid, and secondly to make it a cost effective option in the rest of the country. Partnership working, flexible future proof infrastructure, innovation and supportive policy, planning and regulation are also prioritised within the plan.

3.6 Although many aspects of the plan may have no direct environmental effects, it is important to recognise that the overall target is likely to result in a substantial increase in the production of biomass, as supported by the Bioenergy routemap. In general terms, biomass feedstocks can include: wood and residues from forestry and wood-processing industries, agricultural residues, co-products and purpose-grown energy crops. There are many ways of converting these materials into heat, and this can influence their environmental impact.

3.7 Ways of meeting the targets were discussed by consultees who responded to the REF. Some proposed a greater emphasis on energy efficiency, whilst others favoured broadening the policy and action on heat to prioritise the commercial and industrial sectors in addition to domestic properties. Several consultees strongly supported the use of waste heat and various forms of microgeneration to the meet the target, whilst others emphasised the need for investment in infrastructure and district heating systems to achieve carbon emissions reductions in the most efficient ways possible. In addition to biomass, these other considerations will together make an important contribution to delivering on the renewable heat target. However, as some (e.g. microgeneration) have already been considered in other SEAs of Scottish Government Policies, and the effects of others will only become apparent at the scheme level, this assessment has only broadly explored the environmental impacts which are likely to arise from a substantial increase in biomass production, harvesting and consumption in Scotland in order to highlight the most likely significant environmental effects.

Predicted effects of the renewable heat target

Climatic factors

• Will the plan contribute to climate change mitigation by helping to reduce greenhouse gas emissions?
• Will the plan help to achieve adaptation to climate change?

3.9 As noted in the previous section, Scotland's major power stations and energy intensive industrial installations accounted for around 40% of Scotland's GHG emissions in 2006, while heat accounted for around 16% of all GHG emissions. The Renewable Energy Framework ( REF) noted that there is proven technology in other parts of European where in rural areas combined heat and power plants often in district heating schemes are widely used. As a result, the aspiration within the RAP is to focus on the use of biomass for heat, to complement the continuing deployment of the Renewables Obligation ( RO) to promote electricity from biomass.

3.10 Whilst biomass feedstocks are generally regarded as carbon neutral, the process of using them can emit CO2 and other greenhouse gases ( GHGs). There are also associated (fossil fuel) energy costs. These can be defined by applying life cycle assessment ( LCA) to calculate the total primary energy inputs from depletable energy resources and the total GHG balance during the complete life cycle of a biomass energy feedstock. Using this method, and whilst noting the inherent uncertainties in this type of assessment, research has shown that considerable savings in GHG emissions and depletable energy can be achieved by biomass, heat, and combined heat and power (over 90%, depending on the systems being compared). ⁴⁶ These are in the same general order as savings which can be achieved from other renewable electricity and heat technologies. Factors affecting emissions include changes in the baseline over time, and the impact of climate change (e.g. changes to soil temperature generating emissions and influencing crop yields, and altering GHG balance).

3.11 The RAP therefore provides scope to achieve a substantial increase in the share of heat generated from renewables, which in turn could result in a significant decrease in GHG emissions in the energy sector and for Scotland as a whole and contribute to the broader EU all energy (electricity, heat and transport) target of 20% from renewable sources. The extent to which this can be achieved will depend on the source of feedstock and technologies involved. It is also important to note that in the longer term, adaptation may be required as climate change is expected to alter the capacity of soils to support biomass production. ⁴⁷ As the government is still in the early stages of defining where renewable heat may be derived from (including heat as a by-product from industrial processes) the specific GHG savings from the RAP cannot be fully defined at this stage in the process. However, it is expected that various provisions within the RAP, including prioritising the use of certain approaches including woody biomass and domestic microgeneration and promoting the proximity principle, will help to maximise the contribution of the sector to reducing climate change emissions.

There is potential for cumulative significant environmental effects in relation to climatic factors, arising from the routemap proposals and actions over the long term.

Air quality

• Will the plan have adverse effects on air quality?
• Is the plan likely to have any specific implications for existing AQMAs?

3.11 The baseline analysis showed that there are several areas which have been designated as Air Quality Management Areas ( AQMAs) due to concentrations of air pollution. Combustion of biomass for heat / energy can release air pollutants, such as NOx and SOx, with the level and type of pollutant emitted depending on the chemical composition of the individual feedstock, and the technology used. Biomass boilers are known to generate particulates ( PM2.5 and PM10), at a lower level than coal but at a higher rate than gas. Particulates have the potential to generate adverse effects on respiratory health. Air pollutants may also be emitted at other stages in the life cycle, for example ammonia arising from the use of fertilisers during crop production.

3.12 Research on the air quality impacts of biomass energy technologies has shown that net emissions are largely dependent on the energy source which biomass energy is replacing. Although emission of some pollutants is determined by fuel characteristics, the choice of electricity / heat generation technology, including abatement systems, can also have a significant impact on non- GHG emissions. In some instances the technology can be more relevant than fuel characteristics. The Scottish Government research confirmed that, although the overall impacts of biomass boilers on air quality may not be cumulatively significant, there will nevertheless less be a need to provide further guidance on appropriate abatement measures to avoid adverse impacts in sensitive areas.

3.13 In response to the REF, numerous stakeholders recognised the issues around biomass and air quality, and sought clear guidance on the matter. Various options for mitigation were discussed, including use of newer technologies and abatement measures. In a particularly detailed response to the REF, Dundee City Council emphasised the importance of taking into account the new objective of reducing exposure to PM2.5 in urban areas by 15% between 2010 and 2020. This is produced by biomass boilers and is known to have particular health implications. In addition, it was noted that some sources of biomass can generate other harmful emissions to the air. DCC felt that this underlines the importance of ensuring that quality boilers with abatement technology that is capable of removing these pollutants are installed in urban areas.

3.13 Research suggests that changes in emissions from increased biomass use are most likely to impact on those areas of air quality that are already affected by traffic and combustion. ⁴⁸ It is also worth bearing in mind that the RAP specifically aims to increase levels of biomass in rural areas which are off the gas grid. This could minimise any increase in particulate emissions, given that the biomass is likely to offset coal as opposed to gas (the former generating higher levels of emissions). In addition, there are relatively few AQMAs designated in rural areas, and therefore a substantial proportion of the installed capacity could be expected to avoid exacerbating existing air quality problems and generating significant secondary effects on human health.

There is potential for localised negative effects on air quality arising from an increase in biomass energy production. Monitoring is therefore proposed to identify whether or not these effects could be significant where air quality management targets defined locally or for AQMAs are in danger of being breached. Where this is established, mitigation measures should be put in place to address any significant adverse effects.

Population and human health

• Will the plan avoid generating adverse effects on health arising from environmental pollution?
• Will the plan support the broader aim of reducing fuel poverty?

3.14 Emissions released into the atmosphere from combustion of biomass can adversely affect human health. However, as noted in the previous section, this will vary depending on the type of fuel and combustion technology which is displaced by the biomass and is not expected to be significant. However, several AQMAs in Scotland coincide with areas where there are existing levels of social exclusion and vulnerability to respiratory problems such as asthma is linked with higher levels of deprivation. As a result, there is potential for negative individual or cumulative secondary effects on human health arising from the proposed plan. These would, however, be avoidable if the monitoring and mitigation proposed for the previous heading are taken forward.

3.15 Combined heat and power schemes can be more efficient, substantially reducing fuel costs. The Scottish Renewables Heating Pilot Report ⁴⁹ concluded that, overall, the renewable-based systems tested have the potential to make a significant contribution to reducing fuel poverty. However, biomass in the form of a heating system that uses wood fuel, is likely to remain suitable for only a relatively small proportion of the fuel poor, mainly as a result the uncertainty over long term supply and cost of wood pellets and there are also difficulties in identifying homes that are suitable for biomass systems. Consequently, at this stage it remains unclear whether this aspect of the RAP could generate significant positive effects in relation to fuel poverty.

The potential for localised secondary negative effects on human health arising from the air quality is likely to be minimised by the suggested monitoring and mitigation measures.

Biodiversity, flora and fauna

• Will the plan have effects on protected sites or species?
• Will the plan impact on wider habitat networks including woodlands?

3.16 The impact of biomass (in the case of energy crops) on different habitats and species can vary, according to the crops grown and the land use that they replace. For agricultural residues, this can also depend on the intensity of extraction. Conversion of natural vegetation to agricultural use is likely to negatively impact on biodiversity. However, conversion from set-aside or degraded areas to cropped areas can result in positive effects. Removal of forest residues, such as brash, can have direct and indirect adverse effects on biodiversity.

3.17 SNH assessed the effects of its biomass energy policy on natural heritage within a voluntary SEA relating to its policy proposals. ⁵⁰ This highlighted a range of potential issues arising from biomass, including the effects on woodland removal (disturbance, dust, noise, loss of feeding areas), habitat change arising from planting, particularly where it takes place on or close to protected biodiversity sites. There are also broader issues arising from sedimentation, pollutant run-off and air pollution arising from biomass generators. Research on the likely area of land required to accommodate biofuels suggests that very significant land use change would be required to provide sufficient arable capacity to accommodate energy crops. This in turn could have effects on biodiversity as a result of habitat loss. However, many of these effects could be reduced or avoided through good practice in sustainable land and forestry management, including planting strategies, the timing and method of harvesting, choice of crops and retention of deadwood within native woodlands.

3.18 The SEA of proposals for permitted development rights for domestic microrenewables also identified the potential effects arising from the installation of some technologies, including solar energy, on bats within domestic properties. ⁵¹ Further research is proposed to provide a clearer evidence base from which mitigation, such as guidance on installation, can be developed.

3.19 Application of the UK Forestry Standard ⁵² to woodland creation should maximise the benefits of the plan for biodiversity and avoid these negative effects. Some forms of biomass planting and harvesting can bring short term benefits for habitats and species, such as short rotation coppicing, which can benefit birds, and selective forestry thinning, which can improve habitat diversity. The baseline demonstrated that some aspects of the natural heritage are already being affected by climate change, such as seabird populations, and that in the long term this represents a significant threat to natural heritage throughout the country. It is therefore also important to note that the RAP could also generate positive secondary effects on biodiversity over the long term by contributing to a reduction in climate change.

There is potential for localised negative effects on biodiversity arising from this part of the RAP. Mitigation such as appropriate siting and choice of planting can be applied to minimise these effects, and potentially contribute positively to biodiversity.

Soil

• Will the plan result in damage to soil, including soil sealing, erosion, pollution or nutrient depletion?

3.20 Soil is a crucial media for sustaining biomass production. At the same time, unsympathetic planting has the potential to negatively impact on soils, with secondary impacts on other resources including the water environment. As with other environmental receptors, the impacts of energy crops on soil can vary, according to the crops grown, the land-use they replace and, in the case of agricultural residues, the intensity of extraction. Biomass feedstock production impacts on soils mainly in the form of soil erosion and impacts on fertility. Severe erosion is unlikely to occur. However, disturbance of soils with high organic content has the potential to generate GHG emissions, and therefore reduce the benefits of the policy in relation to climate change mitigation identified in paragraphs 3.9 to 3.11 above.

3.21 SNH's assessment of biomass in relation to natural heritage shows that land use change arising from biomass or biofuel planting and management could affect environmental quality. Issues such as pollution and erosion arising from clearfelling, contamination from the disposal of ash, soil compaction and nutrient depletion were all raised as possible pressures arising from this policy sector. Mitigation measures identified included the controlled use of ash as a fertiliser (addressing issues such as contamination and dust) and good practice in land management to avoid soil compaction during harvesting, controls of the application of fertilisers including sewage sludge, planting design and maximising opportunities for natural remediation of contaminated soils arising from willow coppicing.

3.22 The Biomass Action Plan for Scotland noted that most of the impacts arising from the growth and harvesting of wood biomass are addressed through the existing UK Forestry Standard and associated Forestry Commission Guidelines. In addition, the agricultural sector (where in receipt of grant funding) is required to comply with Good Agricultural Environmental Conditions (the GAEC) which covers avoidance of soil erosion, retention of organic matter and soil structure and prevention of damage to habitats. ⁵³

There is potential for localised negative effects on soils arising from this part of the RAP. Existing mitigation measures, including appropriate siting and choice of energy planting can be applied to minimise these effects. Negative secondary effects on climate change arising from disturbance of soils during harvesting can also be minimised through appropriate locational decisions.

Water

• Will the plan result in acidification, eutrophication or other contamination of water bodies?
• Will the plan result in a significant depletion of water resources, through planting or abstraction required?

3.23 The baseline analysis showed that some parts of Scotland are at particular risk from diffuse pollution arising from agriculture, with Nitrate Vulnerable Zones ( NVZs) having been identified in the east coast, central belt and Ayrshire. ⁵⁴ An increase in biomass production could exacerbate this environmental problem as a result of the associated land management activities which it may generate. The impact of energy crops on water can vary depending on the crops used and the land use they replace. There is the potential for some crops to consume relatively high levels of water (e.g. willow) and this could lead to negative effects on some important habitats such as wetlands. Negative effects could also arise from any increase in the application of fertiliser or pesticide to energy crops, which in turn could result in diffuse pollution, eutrophication and acidification. However, in some cases existing problems of nitrate pollution arising from arable farming could be reduced as a result of land use change. Disposal of ash can contaminate waterbodies. Ground or surface water bodies could be affected, depending on the form and location of activities.

3.24 No effects on the marine environment are anticipated from this part of the RAP

3.25 In light of these potential effects, it is important that the policy is applied alongside established good practice in siting, installation and / or land management, in order to avoid these issues arising. The Biomass Action Plan notes that this type of activity will be regulated under the Water Environment (Controlled Activities) Regulations 2005, which ensure that adverse effects on the water environment are avoided or minimised and that the application of the UK Forestry Standard will also mitigate adverse effects.

There is potential for localised negative effects on water arising as a result of increased risk of pollution and water consumption. However, these are likely to be effectively mitigated through existing regulatory regimes and further good practice in land management.

Material assets: waste

• Will the plan contribute to the aim of reducing waste and / or promoting its sustainable management?

3.26 The RAP identifies a number of actions that aim to support the further development of the energy from waste sector as a contributor to the renewable heat target. Whilst wider policies for waste in Scotland aim to substantially reduce the level of waste which is generated in the first place, the use of waste to generate heat should make some positive contribution to wider waste objectives.

3.27 It is expected that a share of renewable heat will come from harnessing heat generated during waste management processes. This will help to offset the negative impacts on climate change that can arise from some forms of waste management, and thereby contribute positively to the environmental performance of the waste sector as a whole.

Overall, positive effects in relation to waste management and infrastructure are predicted as a result of the renewable heat target.

Material assets: transport infrastructure

• Will the plan generate significant additional road based transport movements?
• Will the plan put pressure on existing transport infrastructure capacity?
• Is the plan expected to make best use of sustainable modes of transport?

3.28 There is potential for an increase in overall traffic movements to arise over the lifecycle of the technologies involved. The RAP aims to minimise this, partly by promoting stronger links between the location of bioenergy sources and end users of the energy generated (the proximity principle), thereby minimising the incidental emissions which could arise from associated transportation requirements.

3.29 By making better use of heat as a by product from waste facilities, there could be opportunities to reduce the need for other sources of energy which are more dependent on importing of additional material and therefore likely to incur higher levels of transport movements overall.

Overall, generally neutral effects in relation to transportation infrastructure are expected as a result of the emphasis within the RAP on the proximity principle and making best use of existing energy sources.

Cultural heritage

• Is the plan likely to generate significant effects on the historic environment by resulting in the loss of or damage to key resources?
• Could the policy generate adverse effects on the setting of protected historic sites and buildings?
• Does the plan provide an opportunity to enhance (where appropriate) the historic environment?

3.30 Land use change arising from biomass planting can have repercussions for the historic environment. According to English Heritage ⁵⁵, crop cultivation has the potential to damage archaeological remains as a result of planting processes, root growth (impact depending on the crop type), hydrological impacts, the eventual retrieval or disposal of plants and rhizome harvesting. The cultivation of energy crops is considered to be less benign in archaeological terms than retaining sites within permanent pasture and may be more damaging than some other types of crop cultivation. There may also be adverse effects arising on the setting of some resources and changes to broader culturally important landscape characteristics, depending on the extent and type of planting.

3.31 The risk of damage to the historic environment is dependent on the method of planting and harvesting proposed. Some crops used in bioenergy tend to have a higher water requirement, with the potential for adverse effects on archaeology which is preserved within wetland areas. Retrofitting schemes and technologies into existing domestic properties has the potential to adversely impact on some historic buildings or townscapes.

3.32 Mitigation is likely to be identifiable at the site level. EIA is generally required where an application is made to plant areas of previously uncultivated or semi-natural land. The effects of retrofitting biomass plant could be minimised at the project level through selection of appropriate technologies and sensitive approaches to installation. Where significant cumulative effects are identified at a local level, the avoidance of scheduled sites and the setting of other resources could help to minimise the significance of any effects arising from land use change.

There is potential for the target for renewable heat to generate localised adverse effects on the historic environment. It is expected that these effects could be avoided through good practice in land and forestry management, the application of relevant consent regimes at the local level, and selection of appropriate technologies and installation techniques.

Landscape

• Is the plan likely to generate adverse effects on landscapes by changing their character or visual qualities?
• Is the plan likely to affect any particularly valuable or sensitive landscapes?

3.33 The SNH Natural Heritage Futures Prospectus for Forests and Woodlands (updated 2008) suggests that increasing demand for renewable energy from biomass is likely to lead to higher levels of agricultural land being planted with short rotation coppices. ⁵⁶ Planting and harvesting of energy crops has the potential to generate landscape effects and the likely scale of planting that will be required to reach the 11% target is likely to be significant. Impacts could take the form of changes to existing landscape character as a result of the deployment of specific crops, loss of landscape diversity, or alterations to woodland structure which in turn could have broader visual implications.

3.34 These effects can, however, be minimised through appropriate land management and siting solutions. Application of good practice techniques, as defined in guidance such as the UK Forestry Standards should ensure that landscape effects are minimised. As noted in the Biomass Action Plan for Scotland and by SNH in their Natural Heritage Futures Series, the Forestry Commission has produced guidance on short rotation coppice in the landscape, which can be used to develop appropriate mitigation of landscape and visual effects arising from certain types of biomass feedstocks.

3.35 Particular care will be required in some landscape character types where proposed feedstocks could significantly alter the existing landscape character as defined in relevant Landscape Character Assessments. Expansion of planting in and around landscapes which have been formally designated for protection, designed landscapes and ancient woodlands will require a particularly sensitive approach.

There is potential for delivering the target for renewable heat to generate localised adverse effects on landscapes. These effects could be avoided through application of good practice in land management including Forestry Commission guidance.

Proposed mitigation schedule

3.36 Based on the analysis above, and reflecting the high level nature of the RAP itself, the following broad mitigation measures are proposed:

Table 5: Proposed mitigation measures

Proposed monitoring framework

3.37 Given the focused nature of this assessment, it is proposed that monitoring focuses only on the potential significant environmental effects which could be generated by the renewable heat target. The RAP is likely to take the form of a 'live' document and as a result will be continuously reviewed. This will provide opportunities for monitoring to feed into any future iterations of the policy. As a result of the issues identified above, the following environmental monitoring measures are proposed:

• Annual evaluation of contribution of renewable heat to energy production in Scotland. It is expected that can be achieved through ongoing research and monitoring undertaken by the Scottish Government. The stated target should be the main indicator against which progress can be measured.
• Continuous monitoring of air quality and further assessment of any issues arising from increased levels of biomass. Air quality monitoring is already undertaken for designated AQMAs. It is proposed that this information can provide a good indication of whether stated thresholds are likely to be breached, thereby generating significant negative effects (on air quality and potentially health) and triggering the mitigation measure proposed above.
• A longer term review of land use change arising from increased levels of biomass feedstock production. There is no single dataset which could be used to achieve this at present. However, existing data, such as that routinely gathered by the Scottish Government to inform its agricultural grant schemes, could be used as a starting point to help establish how land use has changed as a result of the uptake of biomass opportunities. This in turn could be used to identify any significant secondary effects arising for other aspects of the environment such as landscape, cultural heritage, soil and water. Consultee views on the need for, and timing of this monitoring proposal, would be welcome.

Conclusion

3.38 Overall, this assessment has shown that the proposed 11% renewable heat target has the potential to generate significant positive effects in relation to the climate change mitigation agenda. However, taking into account the particular emphasis within the RAP on biomass as a key source of renewable heat, there are numerous potential negative effects which could also arise at a more local level. Given that this type of technology has not previously been deployed at this scale, many of these effects are difficult to fully define. In addition, existing regulatory regimes and controls mean that many potential effects are likely to be avoided at the project level as plans become more developed. However, the SEA has provided an opportunity to broadly consider the environmental consequences of this aspect of the RAP and identify high level monitoring and mitigation measures that should ensure that the benefits of the policy far outweigh its negative effects. This will maximise the local as well as global environmental benefits of the RAP.

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