This document provides additional ecological surveys and assessments conducted for the proposed Pen y Cymoedd Wind Farm project in Wales. Nightjar and bat surveys conducted in 2009 confirm the findings of previous 2008 surveys, showing low risk of negative impacts. Assessments of private water supplies and the grid connection route found negligible impacts with mitigation. Further surveys identified minor road modifications needed for turbine deliveries. Measures to reduce peat disturbance and protect the Craig y Llyn SSSI were also outlined. A habitat management plan will aim to restore blanket bog and heath habitats affected by forestry activities.

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prepared by
PEN Y CYMOEDD
NEATH PORT TALBOT
RHONDDA CYNON TAF
SOUTH WALES
Supplementary Environmental Information
NON-TECHNICAL SUMMARY
August 2010

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CONTENTS PAGE
1.0 INTRODUCTION .......................................................................................................................................... 1
Overview............................................................................................................................................................... 1
2.0 ECOLOGICAL SURVEYS ............................................................................................................................ 1
Nightjar Survey 2009 ............................................................................................................................................ 1
Bat Survey 2009 ................................................................................................................................................... 2
3.0 PRIVATE WATER SUPPLY ASSESSMENTS ............................................................................................. 3
4.0 TRAFFIC ASSESSMENT AND SAFETY ..................................................................................................... 3
5.0 GRID CORRIDOR SURVEYS ...................................................................................................................... 3
Hydrological Assessment ..................................................................................................................................... 4
Archaeological Assessment ................................................................................................................................. 5
6.0 REDUCING THE IMPACT ON THE CRAIG Y LLYN SSSI.......................................................................... 5
7.0 FURTHER MINIMISING THE IMPACT ON PEAT DURING CONSTRUCTION.......................................... 6
8.0 HABITAT MANAGEMENT AND RESTORATION PROPOSALS................................................................. 7

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4. Pen y Cymoedd Wind Farm SEI: Non-Technical Summary
1
1.0 INTRODUCTION
Overview
1.1 This is the non-technical summary of the Supplementary Environmental Information (SEI) submitted to
the Department of Energy and Climate Change in respect of the Pen y Cymoedd Wind Farm.
1.2 On 17 November 2009, an application for consent for the Pen y Cymoedd Wind Farm was submitted to
the Department of Energy and Climate Change under Section 36 of the Electricity Act 1989. That
application was accompanied by an Environmental Statement (ES) and non-technical summary (NTS).
Full details of the application and ES are set out in those documents.
1.3 At the time of submission of the application and ES, it was agreed that additional environmental
information would be provided in respect of ecology (nightjars and bats) and the underground grid
connection.
1.4 This document is a summary of the SEI, which provides additional information on the natural and
human environment of the area where the Pen y Cymoedd Wind Farm would be situated. It also
provides further information on the construction, operational and decommissioning phases of the
development and the measures that will be put into place to reduce the impacts as described in the ES,
with specific regards to peat and to avoid damage to the Craig y Llyn Site of Special Scientific Interest,
as well as a revised landscape scale proposal for habitat management.
2.0 ECOLOGICAL SURVEYS
Nightjar Survey 2009
2.1 The ES contained the results of Nightjar studies undertaken in 2008. These studies concluded that
there would not be a significant loss of nightjar habitat.
2.2 To provide an impact assessment and accurate baseline against which to monitor nightjar and establish
flight heights with greater accuracy, further survey and radio tracking studies were undertaken in 2009
using the same methods and expert ecologists as in 2008. The primary aim of this continued study was
to establish the risk to nightjars of collision with wind turbines.
2.3 The results of this additional study show that nightjars are generally only active for about 1.5 hours
around dusk and 2 hours around dawn i.e. 3.5 hours per day. Outside of this time nightjars are resting.

5. Pen y Cymoedd Wind Farm SEI: Non-Technical Summary
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2.4 The additional study confirmed the findings of the ES. Nightjars were rarely recorded flying at blade
height, and indeed, spent very little time airborne at all. Given that most flight observations were of
birds flying low, and that the birds are only active on site for a very short period of time each day, it is
concluded that collision risk in general is very low.
2.5 In response to concerns from The Royal Society for the Protection of Birds that noise from the turbines
may mask the nightjar's ‘churring’ calls, a literature search was undertaken. Subsequently, in the
absence of any published information of such an effect being experienced, and based upon the
ecologist’s expert opinion, any impact as a result of noise disturbance is considered not to be
significant.
Bat Survey 2009
2.6 The four transect routes surveyed in September 2008 were once again surveyed in September 2009,
following the same guidance and methodologies employed in the main ES. The purpose of this further
survey was to compare results with the previous year in terms of the amount of bat activity.
2.7 Each transect again picked up bat activity within the forest during September 2009. The vast majority of
bats or bat passes recorded were from common pipistrelles. Occasional soprano pipistrelle and Myotis
bats were detected. Guidelines on the consideration of bats in relation to wind farms classify
populations of Myotis species as being of low risk from wind farms, with pipistrelles classed as being of
medium risk from wind farms.
2.8 Bat activity within the forest is mostly seen at forest edges which are a favoured feeding area of many
bat species. In conifer forests, where forest roads cut through forested areas, this provides ideal
sheltered feeding for pipistrelles, who will feed on the midges that are also extremely common in conifer
forests. Areas of clear felled trees or unplanted areas tend to see less bat activity.
2.9 Opening up the forest to site turbines will create more ‘forest edge’ or sheltered feeding areas for the
bats. To mitigate against the likelihood of these bats coming into contact with turbine blades, the
minimum separation distance of 50 metres, recommended in guidance between turbine blade and forest
edge, will be maintained.
2.10 The results of the 2009 surveys confirm the 2008 survey results and conclusions. The species
identified most frequently on the site were common pipistrelle. No species classed as being of high risk
from wind farms were detected during these further surveys. It is unlikely that the development will
have any significant impacts on the local bat populations. Ongoing monitoring will continue during the
operational life of the wind farm and, if impacts were to occur, further mitigation would be considered.

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3.0 PRIVATE WATER SUPPLY ASSESSMENTS
3.1 The main ES concluded that there would be no significant impact on private water supplies. However,
the developer carried out more detailed assessments on each of the seven properties identified during
the main surveys, and a further property was identified following concerns raised during the community
consultation process. Hydrology specialists visited each of the properties and made an assessment
aiming to identify the potential risks from the proposed Pen y Cymoedd Wind Farm on the quality and
quantity of water serving the private water supplies.
3.2 The assessments concluded that the risk to all but two of the properties would be negligible. The two
exceptions having a low risk.
3.3 The SEI includes commitments to actions that the developer will take at construction to reduce the
potential for a detrimental impact on the water supplies. As a result of these commitments, residual
minor effects on the hydrological environment will be short term and temporary, and are unlikely to
result in any long term/fundamental changes to the quality and quantity of water serving the supplies.
Ongoing monitoring will be carried out to ensure this is the case.
4.0 TRAFFIC ASSESSMENT AND SAFETY
4.1 On the 18
th
of March 2009, a test drive by a lorry with a representative abnormal load took place with a
police escort to identify where any highway modifications would be required. As the majority of the
proposed delivery route is on major roads with two or more lanes, the results of this report identify only
four locations where minor road modifications are expected to be required. The minor modifications
include the temporary removal of road signs and the widening of junctions to make sure that the
delivery of turbine components will not cause unnecessary impact on other road users. The finer detail
of the expected modifications will be described in a Traffic Management Plan, a document which is
normally agreed with the relevant authorities prior to delivery of any turbine components. The Traffic
Management Plan will also detail the proposed timescales and schedules for the larger turbine
components, e.g. tower sections and blades, in order to inform relevant authorities and members of the
public when the deliveries are likely to take place.
5.0 GRID CORRIDOR SURVEYS
5.1 To minimise environmental effects, Nuon took the decision to bury the electricity export cables
underground between the on-site substation in the forest and the off-site substation where the wind
farm is expected to connect to the National Grid at the Hirwaun Industrial Estate. As this decision was
taken towards the end of the EIA process, hydrological and archaeological surveys were not complete
when the main ES was submitted.

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Hydrological Assessment
5.2 An assessment of the potential hydrological, hydrogeological and geological effects associated with the
underground grid connection route has been undertaken.
5.3 The chemical quality of the watercourses sampled by the Environment Agency (EA) within the site and
the main rivers near the site is assessed as being close to chemically unpolluted. The biological quality
is good and the area is known to support spawning fish. The nitrate and phosphate levels are also low
and nutrients found in the watercourses can occur naturally and are not necessarily bad for the
environment. In the past, the area was affected by industrial and minewater discharges which caused
increasing water acidity and impoverished the ecosystem.
5.4 The EA has records of several public water abstractions within the vicinity but no private water supplies
were identified within 500 m either side of the grid connection corridor. The public water supply
abstractions were considered sensitive to the development as they are susceptible to changes in quality
and quantity that can be caused by the construction, operation and decommissioning of the grid
connection. The appraisal has also established that the grid connection corridor is located in an area
that is not susceptible to flooding.
5.5 The appraisal also established that the upper areas of the grid connection corridor are underlain by
peat. Peat is very sensitive to construction activities, as poor construction practice and sediment
management can have detrimental impacts on the stability and hydrology of the overlying peat.
5.6 A comprehensive suite of mitigation measures has been incorporated into the SEI following the
identification of the key issues and risks. In addition, an Environmental Management Plan and Pollution
Prevention Plan and specific mitigation techniques for the construction, operation and decommissioning
phases will be implemented to protect the groundwater and surface water resources from pollution.
5.7 Ongoing monitoring will be incorporated to provide reassurance that the established mitigation
measures are effective and that the development is not having a significant adverse impact upon the
environment. The ongoing monitoring will also indicate whether further investigation is required and,
where pollution is identified, additional mitigation measures can be implemented to prevent, reduce or
remove any impacts on the water environment.
5.8 Overall, the effects on the hydrological, hydrogeological and geological regime in the area of the Pen y
Cymoedd Wind Farm grid connection are considered to be negligible and not significant.

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Archaeological Assessment
5.9 The Glamorgan-Gwent Archaeological Trust, Projects Division (GGAT Projects) have undertaken an
assessment of the archaeological effects of the proposed cable connection to the off-site substation.
The assessment reviewed information held by the regional Historic Environment Record and the
National Monument Record, as well as cartographic and documentary sources.
5.10 There are nine sites of archaeological interest identified within the grid connection study area. Of these,
only one, Ffos Toncenglau Dyke, is a Scheduled Ancient Monument (SAM). The others are minor sites
of only local interest.
5.11 To mitigate the effect on the Ffos Toncenglau Dyke, the cable trench will, if possible, be located in the
middle of the existing forest track and the dyke suitably fenced. Such measures will ensure there will
be no effect on the dyke. If locating the trench within the forestry track is not possible, the entirety of
the cable trench within the scheduled area will be subject to full archaeological excavation prior to any
development starting. In accordance with the monument’s scheduled status, the developer will consult
Cadw prior to the commencement of development, and obtain Scheduled Monument Consent in
addition to deemed planning permission. Mitigation measures could include an archaeological watching
brief, field excavation or full excavation prior to any construction activities taking place. Such measures
will ensure that there will be no effect to the dyke.
5.12 Similar mitigation measures, including consultation with Cadw, will be undertaken in relation to the other
historical sites. Such measures will ensure there will be no impact on these sites.
5.13 The Rhondda Historic Landscape falls within the study region which represents one of the largest and
best-known mining conurbations and coalfield communities in Britain. As a result of this, an
Assessment of Significant Impacts of Development in Historic Landscapes (ASIDOHL 2) was carried
out. The overall significance of the impact of the grid connection corridor on the Rhondda Landscape of
Special Historic Interest is considered to be moderate.
5.14 The overall conclusion of the assessment is that with appropriate mitigation, including monitoring
through the construction period, any direct effects on the known archaeological resource in the vicinity
of the corridor will be reduced to none. It is also not considered that the development would greatly
reduce the capacity for understanding or appreciating the landscapes historical meaning or significance.
6.0 REDUCING THE IMPACT ON THE CRAIG Y LLYN SSSI
6.1 As described in the main ES, an existing forestry track crosses the southern area of the Craig y Llyn
Site of Special Scientific Interest (SSSI). The SSSI is designated primarily for its hollows, high cliffs,
ravines, flushes and associated montane vegetation. The boundary includes an upland section of acid

9. Pen y Cymoedd Wind Farm SEI: Non-Technical Summary
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grassland, which extends to the western edge of the A4061, the main road that links the Rhondda and
Neath Valleys. It is proposed that the wind farm infrastructure (track upgrade and grid connection
cabling) will be installed within the existing track margins.
6.2 The conclusion of the ecological survey from the main ES was that the upgrading of the forest track and
the burial of the twin 132 kV cables could be done sufficiently within the existing track margins so as to
not significantly affect the SSSI.
6.3 Prior to construction, detailed construction method statements and a Water Management Plan will be
produced, following consultation with the local authority and Environment Agency Wales (EAW). These
documents will detail the most appropriate construction methods and water management techniques to
reduce the impact on the hydrological environment and will take into account up-to-date and relevant
industry guidance. The documents will be agreed with the relevant authorities, prior to construction and
will ultimately govern the construction methods that will be used.
6.4 Methods implemented to reduce the potential for impact on the SSSI will include not allowing any
rubbish to accumulate or plant to be refuelled within the SSSI boundary or wider catchment. In
addition, no excavated material will be allowed to accumulate outside of the existing track margins. The
use of settlement traps, silt fences and straw bales will be used to reduce and prevent excavated
material, such as soil particles, from entering streams.
6.5 The methods mentioned above, along with ongoing survey by ecology and hydrology specialists, should
ensure that damage to the SSSI and its qualifying features will be avoided.
7.0 FURTHER MINIMISING THE IMPACT ON PEAT DURING
CONSTRUCTION
7.1 As described in the main ES, prior to being planted by forestry, a proportion of the site upon which the
development is being proposed was overlain with peat and would have functioned as a mosaic of
habitats including blanket bog and dry heath. It is widely recognised that forestry has an adverse effect
on these increasingly important habitats.
7.2 The submitted design of the wind farm avoided the areas of more favourable habitat that still had some
existing blanket bog habitat, with the exception of a 0.625 hectare (ha) area in the east of the site.
However, some impact on peat under conifer plantation was unavoidable. In order to give confidence
that this impact would be minimised as far as possible, the developer is committed to the
implementation of a protocol, which will further consider the impact on peat, with a specific objective to
reduce that impact when confirming the final location of each turbine and it’s associated infrastructure.
This protocol will be implemented between the felling and construction phase of the development.

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7.3 The surveys and process that will inform this protocol will be drafted and agreed with environmental
bodies such as the County Borough Ecologists and Countryside Council for Wales, Forestry
Commission Wales and Environment Agency Wales. The information gathered through the
implementation of this protocol will also be shared with the Working Group responsible for the delivery
of the Habitat Management Plan as discussed in the next section.
8.0 HABITAT MANAGEMENT AND RESTORATION PROPOSALS
8.1 In July 2009, Forestry Commission Wales produced its Woodland Strategy for Wales. The strategy
gives a clear commitment that, ‘where there is a clear ecosystem service benefit, existing non native
woodlands are restored to open habitat’. The publication of this strategy has allowed a review of the
restoration proposals to take place. As a result of this review the habitat management and restoration
proposals have increased from approximately 400 ha to approximately 1500 ha.
8.2 The areas that will be managed and the methods by which they are identified and managed will be
drafted and agreed with a Project Board, which will include representatives from Countryside Council
for Wales, Neath Port Talbot and Rhondda Cynon Taf County Borough Councils, Forestry Commission
Wales, the Royal Society for Protection of Birds and Cadw. The results of the surveys will inform the
detail of a live document, subject to review and revision throughout the life of the wind farm (called a
Habitat Management Plan).
8.3 The Project Board shall consider and advise the detail of the Habitat Management Plan, expected to
concentrate, where possible, on the following principal objectives:
 Regeneration of peat body functionality.
 Promotion of blanket mire and dry heath habitat.
 Promotion of native woodland.
 Management of stream corridors.
 Promotion of feeding habitat for honey buzzard in the Resolven Forest area.
 Promotion of appropriate management for nightjar.
 Promotion of public enjoyment, understanding and involvements with delivery of the Habitat
Management Plan.

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8.4 The developer will commit to providing £3 million of funding for habitat management over the life of the
wind farm and it is expected that the Project Board will be able to identify new opportunities throughout
the lifetime of the wind farm, working towards ongoing landscape scale management beyond the
current proposals.

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NUON Renewables
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+44 (0)1792 455 004
www.nuonrenewables.com
www.penycymoeddwindfarm.info
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Y Lanfa
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