Detailed comments on Peat and Habitats We have a number of detailed comments and advice in relation to habitats and these are presented below with reference to specific sections of the ES. Several may be appropriate for consideration in method statements should consent be given. There are several references to ‘best practice’ within the ES and it is important to note that SNH, SEPA and the Scottish Renewables Forum (SRF) are developing a web based guidance which should be available later this year. More specifically, SNH, FCE (Forestry Civil Engineering) and members of the SRF are developing guidance on the construction and maintenance of Floating Roads. We anticipate that this will be available in spring 2010. We recommend that, should the wind farm be granted planning permission, there should be a condition in place that requires the developer to apply current best practice. • Further clarification of what is meant by a “Class 1 Habitat” (referred to in Paragraphs 4.36
Chapter 8. Ecologyand 4.57) would have been helpful as this term is not used in the Habitats Directive. Nor is it clear whether there is any relationship with the Habitat Classes A, B & C indicated on Figure 4.15. • Page 6, Paragraph 5.36, 1st bullet. We advise that peat turfs at least 300mm thick, rather than the 200mm stated, are used to improve their restoration potential. • Page 7, Paragraph 5.36, 3rd bullet. It is important that any water pumped from excavations goes into settlements or through a ‘Silt Buster’ before being discharged into the vegetation. This is particularly important in areas of clay as identified in Chapter 11, Hydrology and ground conditions, Page 18, Paragraph11.54. • Page 8, Paragraph 5.50. “…there would be a 15m long and 2.5m wide passing place every 400m on the access track”. This contrasts with Chapter 8, Page 43, Paragraph 8.179, “Passing places…will be located at c. 200 m spacings”. This apparent contradiction should be clarified in the Construction Method Statement. Clearly the greater the spacing the smaller the area of habitat loss. • Page 9, Paragraph 5.58. “The on-site tracks will remain in place, though reinstated to a lesser width, when the wind farm is in operation…” There is no mention of this as a mitigation measure in the Ecology Chapter. Whilst it is welcome, there may be an issue with re-widening the tracks to allow access to cranes to either replace damaged turbines or decommission the site. We advise the determining authority to seek clarification as to whether or not track reinstatement to a lesser width post-construction is a firm commitment. • We have a number of comments with reference to page 17, paragraphs 5.126 & 5.127: It is not clear to us what “overheating of the peat” means or how sand in the cable trench will prevent this. The reference to wrapping the sand in geo-textile “to prevent it from washing away” implies anticipation that this structure will act as a drain. Simply compacting the peat as it is returned to the trench should avoid the creation of air pockets which can act in this way. The proposal to introduce clay plugs is welcome and we advise that these should located at every 300mm change in altitude. • Page 19, Paragraphs 5.143 & 5.144. The proposal to agree dewatering operations with SEPA is welcomed. It is important not only that discharges are not pumped directly into watercourses, but that they also avoid sensitive plant communities such as moss carpets. More resilient grass and heath communities are preferred. • Page 19, Paragraph 5.149. “Drainage ditches will be required alongside any road”. The exception to this is Floating Roads for which it is important that drainage ditches are not present – as illustrated in Figure 5.13. • Page 20, Paragraph 5.155. The commitment to developing a Peat Management Plan is welcome although an outline plan within the ES would have been helpful. We advise that a planning condition is added to any consent awarded requiring this to be agreed with THC in consultation with SEPA and SNH. • Page 22, Paragraph 5.163. While the reinstatement of track verges using sub-soil, peat and turf is welcome, it is important that only those quantities necessary for the purpose are used and the ‘opportunity’ to dispose of surplus peat in this manner is avoided. • Page 23, Table 5.3. The aggregate and concrete volumes described here total considerably less than the requirements identified on Page 13, Paragraph 5.86. Given the size of the apparent discrepancy we advise the determining authority to seek clarification on the aggregate, and consequently borrow pit, requirements. • Page 3, Table 8.1. Upland heathland is a UKBAP priority habitat.
Chapter 11. Hydrology and ground conditions• Page 9, Table 8.2. (and again at Page 33, Paragraph 8.142 and elsewhere). Viable areas of UK BAP habitats, particularly those that are also on Annex I of the EC Habitats Directive, are afforded only Regional Importance in the ES. Given their role in contributing to national, and international, targets, we advise that they should be considered as of National Importance. • Page 12, Paragraph 8.36. There is reference here to the “proposed wind farm construction zone”. This is not one of the terms defined on Page 5, Paragraph 8.15. A definition would have been helpful. • Page 12, Table 8.5 (and at various points thereafter). It is unhelpful, and potentially misleading, to separate the data and analysis relating to the “wind farm area” from that relating to the “main site access route”. These areas are integral parts of the proposed development and we therefore advise that they should be treated as such. • Page 12, Table 8.5. The total extent of habitats within the “wind farm area” is 606.14 ha. The total extent of habitats within the ”main site access route” is 1242.34 ha. This contrasts with the introductory statement (Page 1, Paragraph 8.3) that the wind farm area “is c. 574 ha in extent”. • Page 32, Paragraph 8.136 and other sections (eg Pages 75 – 88, Tables 8.22 – 8.34.) “For the purposes of the impact assessment, nature conservation values have been ascribed separately for the wind farm area…and the route…of the main site access, where relevant”. We consider this approach to be inappropriate and advise that all aspects of the impact assessment in relation to habitats and species should have been represented in an integrated manner. • Page 32, Paragraph 8.138. “the majority of the blanket bog within the study area can be classified as ‘active’”. There is no evidence that ‘active’ areas have been mapped separately from inactive areas (and indeed to do so would be exceedingly difficult and of questionable merit). However, if active’ is synonymous with the “Class 1 habitats” referred to at Chapter 4, Paragraph 4.57, Page 16, then there would appear to be some inconsistency with regard to the description and evaluation of the habitat. This point should have been clarified. • Page 43, Table 8.8. Despite the apparent wealth of detail supplied in the ES, it is not possible to verify the extent of impacts independently. To allow an independent assessment this table would have to be re-presented in a transparent manner so that it reports the total area of each habitat affected by the proposed development. • The proposal will lead to the permanent loss of lichen-rich heath. Montane habitats such as this are at particular risk from climate change and we recommend that further consideration should be given to reconfiguring or micrositing of installations as appropriate to avoid loss of or damage to montane habitats. • Page 50, Table 8.11. It is not clear why the impact magnitude for the permanent loss of blanket bog is considered “Low”, when it was considered (page 46, Table 8.9) “Medium” for construction damage/disturbance. Likewise, the impact magnitude for indirect habitat loss/degradation (Page 51, Table 8.12) is considered ‘Low”, again without explanation. Some clarification of the rationale for these conclusions would have been welcome. • Page 53, Table 8.13. It is not clear why Juniper Scrub should experience impacts due to “Maintenance Activities” when habitat loss or degradation arising from the construction or operation of the wind farm does not affect it. Some explanation of this conclusion would be helpful as it may indicate maintenance activities that are not otherwise apparent. • Page 66, Paragraph 8.249. Unless the developer can suggest a more effective way of “maintaining the required work area to a strict minimum” than temporary fencing, then fencing should be a firm commitment rather than a suggestion. • Page 67, Paragraphs 8.251- 8.253. The commitment to ‘best practice methods’ is welcome – but a bit vague. We advise that methods are clearly defined in Construction Methods Statements and the proposed Habitat Management Plan. We advise that should consent be issued that these documents are required through planning conditions. • Page 73, Paragraphs 8.284 – 8.290. The proposal to develop a Habitat Management Plan as part of the mitigation measures is welcome in principle. We advise that the development and implementation of a Habitat Management Plan is made a condition of planning consent issued. • Page 6, Paragraph 11.20. There should be reference here to Allt a’Choire’s designation as an SSSI, notified for its ‘geomorphic system of gullies and alluvial fan’. • Page 11, Paragraph 11.29. “...an extensive network of artificial ditches is used to drain the site”. We advise that blocking these drains would constitute some of the most effective mitigation that could be undertaken at this site. Indeed this would be more appropriate than works on the lower ground proposed within the Outline Habitat Management Plan (Appendix 9.7). We therefore advise that drain blocking should be added to the scope of the Habitat Management Plan. • Page 17, Table 11.6. The peat depth at Turbines 11 and 16 is around 3m. Given the range of peat depths available on the site we recommend that the current locations of these turbines be reconsidered with the aim of relocating them on areas of shallower peat. • Page 18, Paragraph 11.53. “the peat depth on the access track ranges from 0 to 4m deep…”. “Minor modifications to the access track alignment were made following the peat depth survey of the proposed track”. It is not clear whether this means that area of peat 4m deep has now been avoided. • Page 23, Paragraph 11.99 states that “In general, peat across the site is in a degraded state due to artificial drainage and grazing.” This does not seem consistent with Chapter 8, Ecology, Page 32, Paragraph 8.138 which states that: “the majority of the blanket bog within the study area can be classified as ‘active’”. • Page 23, Paragraph 11.100. “In general, the degraded nature of the peat cover and artificial drainage favours the drying of the peat, reducing the potential for the rapid mobilisation of large masses of saturated peat”. It is important to note that this concluded relationship is not entirely consistent with the ground conditions at several recent peat slides. |