Scottish Government: Energy & Climate Change Directorate
Habitats Regulations Appraisal of the Implications of the proposed Forth Energy Grangemouth Biomass development
Blawhorn Moss SAC
05 December 2012
The following appraisal has been prepared by the Scottish Ministers as the Competent Authority for the above proposal.
Description
1
Brief description of the project
The development is for a biomass fuelled electricity and heat generating station at the Port
of Grangemouth, Falkirk with an electricity generating capacity of up to 120MW. The
biomass will be delivered to the plant mainly by ship (directly to Grangemouth port), with
some additional fuel arriving by road or rail.
The principal components of the development comprise of:
 Power plant area
 Fuel storage area
 An electrical switchyard
 A covered conveyor system for transferring fuel
The design of the plant will include:
 A 110m tall stack
 A boiler hall
 A turbine hall
 Main fuel and mixed fuel stores both 20m tall
 Ash silos (12m tall)
 Two auxiliary boilers with a single 55m stack containing two flues.
 A cooling water extraction pipe from within the docks.
 A cooling water discharge pipe into the River Carron.
The main generating station will be located within the existing docks, about 300m away
from the nearest intertidal area. Cooling water will be extracted from within the docks,
and the resulting warm water will be discharged into the River Avon, approx. 300m away
from the main plant.
The development is around 15KM north, north east of the Blawhorn Moss SAC.
2
Brief description of the designated Natura Blawhorn Moss is designated as an SAC for the following qualifying features:
site
 Active raised bogs, and
 Degraded raised bogs
Blawhorn Moss SAC is one of the largest and least-disturbed active raised bogs in the
central belt of Scotland. The vegetation exhibits well-developed hummock and hollow
topography and supports many of the species representative of a raised bog habitat, such
as Sphagnum papillosum, S. magellanicum and cranberry Vaccinium oxycoccos. The area
of the site is 109 hectares.
3
Conservation objectives for Blawhorn Moss
SAC: Active and degraded raised bog habitats
To avoid deterioration of the qualifying habitat thus ensuring that the integrity of the site
is maintained and the site makes an appropriate contribution to achieving favourable
conservation status for each of the qualifying features; and
To ensure for the qualifying habitats that the following are maintained in the long term:
 Extent of the habitat on site
 Distribution of the habitat within the site
 Structure and function of the habitat
 Processes supporting the habitat
 Distribution of typical species of the habitat
 Viability of typical species as components of the habitat
 No significant disturbance of typical species of the habitat
Screening
4
Is the proposal directly connected with, or The proposal is not directly connected with, or necessary to, conservation management of
necessary to, conservation management of the Blawhaorn Moss SAC and therefore further consideration is needed.
the Natura site?
5
Is the operation likely to have a significant
effect on the qualifying interest of Blawhorn
Moss SAC either alone or in combination,
with other plans or projects.
Atmospheric emissions from the operation of the Port of Grangemouth biomass
development could potentially have an effect on:


Active raised bog
Degraded raised bog
The ES and Information to Inform HRA conclude that nitrogen and acid deposition from
the Grangemouth Biomass Plant on its own will not have a likely significant effect on the
site. This is because the 1% process contribution to the theoretical critical load threshold
is not exceeded for nitrogen or acid deposition. Therefore, the project on its own will not
be likely to have a significant effect on Blawhorn Moss SAC.
However, in combination with the other proposed biomass plants (Rosyth, Leith* and
Dundee) acid deposition will have a likely significant effect on the raised bog habitats. This
is because the 1% process contribution to the theoretical critical load threshold is
exceeded for acid deposition. Therefore in combination with the other proposed
biomass plants there would be a likely significant effect from acid depositon on
Blawhorn Moss SAC.
*The Leith biomass proposal has since been withdrawn.
Appraisal
6
Identify the relevant conservation objectives
to consider for the Blawhorn Moss SAC
The conservation objectives to consider are those that relate to the qualifying interests
that may be significantly affected by the proposal.
The relevant conservation objectives for the qualifying interests (active raised bogs and
degraded raised bogs) are:





7
Extent of the habitat on site
Distribution of the habitat within the site
Structure and function of the habitat
Distribution of typical species of the habitat
Viability of typical species as components of the habitat
Can it be ascertained that the proposal/plan The risk to the qualifying interests of the site would be from acid deposition due to
will not adversely affect the integrity of the airborne emissions. The Environmental Statement and IIHRA identified that the process
Blawhorn Moss SAC
contribution to critical load for acid deposition from the Grangemouth Biomass Plant in
combination with the other proposed Biomass Plants (Rosyth, Dundee and Leith) is 2%,
exceeding the 1% threshold above which it could potentially have an effect and therefore
require further consideration (Air Pollution Information System, CEH).
The existing background level of acid deposition at Blawhorn Moss accounts for the vast
majority of PEC (174%), i.e. the critical load (100%) is already significantly exceeded by
74%. Adding the combined biomass plants’ emissions to this background level will result
in a PEC that is 176% of critical load.
However, the effects of acid deposition on raised bog habitats and species are very poorly
understood. The critical load that is set for any given habitat is a theoretical estimate, and
in the case of acid deposition on raised bogs such estimates typically have substantial
margins of error. Even where existing levels substantially exceed the critical load, in this
case by 74%, no link has been established between this level acid deposition and any
measurable changes in the raised bog habitats or species.
The active and degraded raised bog habitats on Blawhorn Moss SAC are both in
“Unfavourable, Recovering” condition (SNH Site Condition Monitoring). However, this
unfavourable condition is attributable to excessive drainage via old ditches and to
overgrazing, both of which are being actively managed to allow recovery. Therefore,
according to current scientific knowledge, the existing impacts on the SAC are not thought
to be from acid deposition, and any minor increase in acid deposition from the biomass
plants would not result in any deterioration in the raised bog qualifying habitats.
Therefore, it can be ascertained that the increase in acid deposition attributable to the
Grangemouth biomass plant proposal, either alone or in combination with other plans
or projects, will not adversely affect the integrity of Blawhorn SAC.
8
Consider whether mitigation measures or No mitigation measures have been proposed or are required.
conditions to be adopted to avoid impacts on
site integrity
Conclusion
9
Can impacts on site integrity be avoided
It can be concluded there will be no adverse impact on site integrity from the proposed
development.