Our ref:
Your ref:
Joyce Melrose
Energy Consents and Deployment Unit
Scottish Government
PCS/119002
None
If telephoning ask for:
Susan Haslam
30 March 2012
By email only to: EconsentsAdmin@scotland.gsi.gov.uk
Dear Ms Melrose
The Electricity Works (Environmental Impact Assessment) (Scotland) Regulations
2000
Section 36 Application for the proposed Dalnessie wind farm 13 km east of Lairg
Thank you for your email which SEPA received on 14 March 2012. We received a copy of the
Environmental Statement (ES) direct from the developer on 2 March 2012.
Advice to the Scottish Government
We ask that the planning conditions in Sections 2, 3, 6 and 7 of Appendix 1 be attached to the
consent. If any of these will not be applied, then please consider this representation as an
objection. Please also note the advice provided below.
Advice for the Developer
For general good practice advice we refer you to Good Practice during Wind Farm Construction
Guidance which is available on SNH's website at www.shn.org.uk. You should also refer to our
Planning and Energy website (www.sepa.org.uk/planning/energy.aspx) for regulatory and best
practice advice in relation to waste management and restoration proposals.
If you wish to discuss a regulatory issue then please consult out local operations team at: Graesser
House, Fodderty Way, Dingwall Business Park, Dingwall IV15 9XB Tel: 01349 862 021.
Should you wish to discuss this consultation, please do not hesitate to contact me on 01349
860359 or planning.dingwall@sepa.org.uk.
Yours sincerely
Susan Haslam
Senior Planning Officer
Planning Service
Ecopy: epc@highland.gov.uk ; Michael.Walker@airtricity.com
Appendix 1: Detailed comments, recommendations and conditions
1.
The Water Environment (Controlled Activities) (Scotland) Regulations (CAR)
1.1
On the basis of the information available and without prejudice to the determination of any
corresponding applications for CAR authorisation, we would expect the proposal to fall into
Category 1 - ‘capable’ of being authorised.
1.2
We can confirm that we have not received any CAR applications from the developer. For
information, modifications to existing small scale culverts are unlikely to require registration
under CAR.
2.
Direct impacts on the water environment
2.1
While the development will result in a large number of new or upgraded watercourse
crossings we are satisfied that the route taken and location of other infrastructure has had
due regard for the water environment. We welcome the level of detail provided in the
watercourse crossing assessment.
2.2
We welcome the inclusion of a 50 m buffer between infrastructure and watercourses which
are considered to have continuous flow and a 25 m buffer adopted for all ephemeral
drainage channels (outlined in section 4.9.3 of ES). We ask that this be ensured by
condition to ensure that micro-siting does not reduce the level of protection recommended
(obviously with the exception of where access tracks specifically require to cross
watercourses).
2.3
We note that the ES states that "with the exception of a limited number of watercourse
crossing identified no infrastructure is planned in areas susceptible to flooding". Our main
issue with regards to windfarm developments and flood risk is in relation to the new access
roads and associated watercourse crossings. We are therefore pleased to note that section
4.9.3 also confirms that all watercourse crossings will be designed to accommodate flow.
2.4
We agree with the assessment in section 11 which suggests that the development is not
likely to have a significant impact on the private water supply at Dalnessie. Although little
information is provided regarding the private water supply at Saval (in the vicinity of the
borrow pit site in Dalchork wood) we consider that it is unlikely that the development will
have an adverse impact on the water supply for these properties. This is owing to the fact
that they lie some 2 km away, in a different watershed and up-gradient of the borrow pit
site.
3.
Pollution prevention and environmental management
3.1
We welcome the mitigation measures included throughout the ES and the inclusion of a
draft CEMP. To ensure that the development does not significantly effect the water
environment and protect downstream sensitivities we request that a condition is imposed
requiring that a full site specific construction environmental management plan (CEMP) is
submitted for approval to the planning authority at least two months prior to the proposed
commencement (or relevant phase) of development in order to provide consultees with
sufficient time to assess the information.
3.2
This document should address all pollution prevention and environmental management
issues related to construction works, including, for example, those relating to peat stability,
the borrow pits (including information on cross sections, elevation of the pit floor and
confirmation of exact extraction volumes), peat management and reuse and all related
environmental monitoring.
3.3
The Non-technical Summary proposes a 100 m micro-siting distance and section 5.3.1
clarifies that micro-siting up to 50 m could be agreed by on-site specialists and micro-siting
of between 50 and 100 m would be with the approval of the planning authority and
appropriate consultees. We are satisfied with this approach. Details of how micro-siting will
be implemented and controlled should be submitted as part of CEMP.
3.4
Please note the issues outlined in sections 4.4, 5.3 and 6.2 of this letter which the CEMP
should also address.
4.
Borrow pits
4.1
Section 5.3.11 of the ES outlines a requirement for approximately 190,800 m3 of
aggregate. We note that borrow pits 1 and 2, which are located in close proximity to the
windfarm, are estimated to be able to supply 258,252 m3 of rock, significantly in excess of
that estimated to be required for the development.
4.2
Two further borrow pits are however identified. Borrow pits 3 and 4 are a significant
distance from the windfarm and if developed will result in the need to upgrade a further 8.8
km of existing forest track (section 4.11.1). We highlight to the determining authority that
there does not seem to be a clear need for this element of the development and that the
environmental impact of the overall development could be reduced if it were removed.
4.3
We ask that detailed information on the environmental management of the borrow pits,
including the information set out in PAN 50 Controlling the environmental effects of surface
mineral workings (Paragraph 53) to be included in the requested CEMP.
4.4
Please also note that the hydrogeological behaviour of faults in proximity to borrow pit 4 is
not known and therefore it is possible that the bedrock permeability is locally enhanced
along the fault line due to a greater fracture density. The fault line could therefore act as
preferential pathways for contaminants to enter groundwater and surface water features.
We ask that the CEMP specifically include details of the measures to be taken to protect
the water environment in relation to this potential issue.
5.
Disturbance of peat
5.1
Significant information on peat depth has been collected and in the main we consider that
the layout proposed avoids the areas of deepest peat on the site. Nonetheless there are a
number of individual turbines which will be located on peat greater than 2 m in depth; micro
siting should be used to ensure the final location of the turbines is on the shallowest peat
available.
5.2
We would have welcomed it if more description of the elements within Table 11.1 had been
provided. We welcome the clear identification of the different elements of excavated
material but are disappointed that the calculations of peat to be disturbed is not then
classified into these elements. Without treatment there are limited uses for the lower layer
of peat, and it would be helpful if at this stage the total amount of this type of peat that will
be generated had been calculated and uses and treatment identified. We also note that the
calculations do not seem to consider the peat disturbed by upgrading existing tracks
(estimated to be 14.8 km) and do not consider the volume of peat disturbed by the borrow
pits. In addition it only considers two borrow pits, where as four are now proposed.
5.3
Nonetheless based on the information provided and in this specific instance we consider
that it seems likely that suitable uses for any disturbed material can be made. We ask that
the finalised CEMP includes a more detailed section on excavated materials which clearly
identifies and quantifies all disturbed areas and uses in line with best practice.
6.
Impacts on peatland and groundwater dependant terrestrial ecosystems
(wetlands)
6.1
We note that large areas of the site are vegetation communities classified as groundwater
dependant terrestrial ecosystems. These include M6, M15, M23, M25 and MG10, all of
which may be impacted. However, the ES notes that the overall mire system on the site is
predominantly ombrotrophic (rain-fed), so the dependency of these habitats on
groundwater is likely to be low in this instance.
6.2
Impacts on these habitats are nevertheless possible from alterations to hydrological
conditions in the peat, for example if access tracks cut off drainage routes. This is also
acknowledged in the ES, and the CEMP proposes drainage arrangements for both floating
and cut tracks to minimise effects on existing hydrology. We ask that full details of these
methods and mitigation measures are included in the finalised CEMP.
6.3
We welcome the production of a draft Habitat Management Plan (Appendix 9-5) and the
proposals for compensatory habitat restoration for blanket bog and wet health and ask that
a condition be applied that a finalised Plan be agreed with the planning authority in
consultation with SEPA and SNH (and thereafter implemented).
6.4
We welcome the inclusion of a 25 m buffer between infrastructure and acid flush and bog
pool features (outlined in section 4.9.5 of ES). We ask that this be ensured by condition to
ensure that micro-siting does not reduce the level of protection recommended.
7.
Decommissioning and final site restoration
7.1
We request that a condition is applied seeking a Decommissioning and Restoration Plan.
The Plan should be submitted at least two years prior to the end of the design life of the
development and be based on the best practice current at the time of submission.
8.
Carbon balance assessment
8.1
Appendix 2 provides our audit of the carbon balance assessment.
9.
Caveats
9.1
Please note that we are reliant on the accuracy and completeness of the information
supplied to us in undertaking our review and can take no responsibility for incorrect data or
interpretation made by the authors.
9.2
This advice is also given without prejudice to any decision made on elements of the
proposal regulated by us. The decision may take into account factors not considered at the
planning stage.
Appendix 2: Carbon Assessment of Section 36 Wind Farms
SECTION 1: SUMMARY OF REPONSE
Issue
If no, is any deficiency
Yes/No significant enough to
affect substantially the
carbon payback period?
Comments
Further requirements to enable positive
validation (where applicable)
Is there sufficient
confidence in the
carbon payback figure
for it to be used by
Scottish Ministers as a
material consideration
in their decision
making?
No
Some information is
missing, in particular
no values are given
for maximum and
minimum carbon
payback periods, as
only expected
values have been
entered into the
carbon payback
spreadsheet.
Section 15.8 – Climate and Carbon Emissions in
the Environmental Statement requires to be
expanded to further clarify the rationale behind
all the data input in the carbon assessment.
The level of significance
will depend on further
information to be provided
by the developer for some
of the data incorporated in
the carbon calculator.
A number of sensitivity
analyses have been carried
out to assess how some of
the potential deficiencies
affect the carbon payback
period - See section 2.
Reference for all the data input in the carbon
calculator needs to be recorded in the relevant
input data sheets.
Provision of maximum and minimum values in
the carbon assessment tool.
SECTION 2: DETAILED RESPONSE
Issue
Yes/
No
If no, is any
deficiency significant
enough to affect
substantially the
carbon payback
period?
Comments
Is all relevant data
inputted as set out in
the tool?
No
No maximum or
minimum values are
given for any of the
INPUT DATA
Maximum and minimum values should be entered
Further requirements to
enable positive
validation (where
applicable)
Data on the relevant
carbon calculator input
parameters, therefore it
is difficult to assign a
level of confidence to
the carbon payback
results.
in the data input sheets of the carbon calculator
so that a confidence range for carbon payback
time can be calculated.
maximum and minimum
values associated to each
parameter is required.
The source of the data have not been recorded in
the carbon calculator.
A number of sensitivity
analyses have been
carried out to assess
how some of the
potential deficiencies
affect the carbon
payback period. The
results of these
analyses are presented
in the comments
column.
CORE INPUT DATA
The source of all the data
provided in the carbon
calculator should be
recorded in the carbon
calculator.
Windfarm characteristics
Further justification/rationale behind the assumed
capacity factor should be provided. If the average
28% Scottish factor based on 2009 data from
Energy Trends is used, then payback period for
the expected values scenario would be extended
by 2 months (10% increase) for the fossil fuel mix
scenario.
Counterfactual emission factors
The most recent values for the three required
counterfactual factors, according to the latest
DUKES publication (July 2011) - Table 5a are:
Grid mix: 0.458t CO2 MWh-1, fuel mix: 0.59t CO2
MWh-1 and coal: 0.909t CO2 MWh-1
Further
justification/rationale
behind the assumed
capacity factor should be
provided.
It is recommended that the
most recent values for the
three counterfactual
factors are used.
If these values are used in the carbon calculator
the carbon payback period for the expected
values scenario would be slightly extended by:
0.6 months (2% increase) for the fossil fuel mix
scenario, and decreased by 2 months (6%
decrease) for the coal scenario and 1 month (5%
decrease) for the grid mix scenario.
Does the data
correspond with the
information provided
in the Environmental
Statement?
No
The level of
significance will depend
on the further
clarification for some of
the data incorporated in
CORE INPUT DATA
Forestry plantation characteristics:
The area of forestry to be felled is not identified in
the Environmental Statement and the rationale
Further clarification on this
data is required.
the carbon calculator to
be provided by the
developer.
behind the average rate of carbon sequestration
emission factor input in the carbon calculator has
not been provided.
Some sensitivity
analyses have been
carried out to assess
how some of the
potential deficiencies
affect the carbon
payback period. The
results of these
analyses are presented
in the comments
column.
Characteristics of peatland before windfarm
development
The source or rationale behind the data provided
for average air temperature at site and C content
of dry peat has not been provided.
Average water table depth is given as 0.2 m.
However, 0.1 m is more likely for intact blanket
bog. Was the 0.2 m value determined by on-site
measurement? If so, this needs to be clarified,
and methods used outlined.
Further clarification on the data used for extent of
drainage around drainage features is required.
The methodology for calculating the average
depth of peat at site is not provided.
Borrow pits
The borrow pits length and width data provided in
the TA A5.2 Borrow Peat Assessment report of
the Environmental Statement is not consistent
with the data provided in the carbon calculator.
The 0.0 m expected figure for average depth of
peat removed from borrow pits is not credible. At
least one of the borrow pits is in an area of peat
as indicated by the superficial geology map (fig.
11.7). The others, according to TA A5.2 Borrow
Peat Assessment report of the Environmental
Statement, have some peat cover.
Access tracks
The length of floating and excavated roads and
The source and rationale
behind this data is
required.
Further clarification is
required.
Further clarification is
required.
The methodology for
calculating this data is
required.
Further clarification of the
data is required
Further
clarification/revision of this
data is required.
Further clarification and
referencing of the data
within this section is
the length of floating road that is drained input in
the carbon assessment are inconsistent with the
data identified in the Environmental Statement. In
addition, the Environmental Statement does not
mention the construction of any rock filled roads,
however, 26,300 m of it is reported in the carbon
calculator.
Improvement of C sequestration
Clarification and further referencing of the water
table data and time required from restoration data
has not been provided.
Choice of methodology for calculating
emission factors
The methodology chosen for calculation of
emission factors was the IPCC default instead of
the site specific methodology. If the site specific
methodology is used, then payback period for the
expected values scenario would be decreased by
almost 1 months (3% decrease) for the fossil fuel
mix scenario.
CONSTRUCTION INPUT DATA
required.
Further clarification and
referencing of the data
within this section is
required.
It is recommended that the
‘site specific values’
methodology is used as
site specific values are
available.
The total volume of
concrete used on site is
required.
Volume of concrete
The volume of concrete input in the carbon
calculator corresponds to the volume of concrete
use per turbine. However, the total volume of
concrete used on site should be reported.
Is there sufficient
evidence that peat/soil
depth measurements
have been probed to
full depth?
Yes
However, there are a number of peat probe points
for which recorded depth is mostly given as 3 m
which are accompanied by the comments ‘Depth
not proven’ or ‘unknown’ in the substrate column.
Does the data
(including peat depth)
correspond with the
Yes
The Peat Landslide Hazard Risk Assessment
Report presented in Appendix 5.1 Peat Landslide
and Hazard Risk Assessment of the
Clarification is needed to
explain what ‘depth not
proven’ and ‘unknown’
mean.
information in the
Halcrow peat slide
assessment?
Is the data credible?
Environmental Statement refers to and identifies
that the methods adopted for the assessment
follow the requirements identified in the Halcrow
Peat Slide Assessment.
No
The level of
significance will depend
on the further
clarification of
inconsistencies and
rationale behind some
of the figures identified
in this section.
Data values have been used without referencing
or justification. No explanation of measurement
methods has been supplied.
There are some inconsistencies between the
figures and references identified in the
Environmental Statement and the carbon
calculator, particularly values related to
measurements and peat depths associated to
borrow pits and access tracks.
In addition, further clarification on the values
provided for some of the parameters identified in
section 2 is needed.
SECTION 3: GOOD PRACTICE
Issue
Is there potential to reduce the carbon
payback through improved adherence to
the SEPA/SNH Good practice during
wind farm construction guidance and/or
SEPA’s Regulatory Position Statement
for Development on Peat?
No – proposal adheres to good practice
While reference to SEPA/SNH good
practice is made throughout the document,
it is essential that this, together with the
requirements under SEPA’s Regulatory
Position Statement for Developments on
Peat, are fully carried out in practice.
Yes –
improved
adherence
would improve
the carbon
payback
Where applicable specify
areas of good practice that
could be introduced to
improve the carbon payback
of the proposal