Slyfield iwmc
Non technical Summary
On behalf of
Thames Waste Management
July
2000
1. introduction
1.1 Thames Waste Management
(TWM) are submitting a planning application for the construction of an
Integrated Waste Management Centre (IWMC) comprising an Energy from Waste [EfW]
plant, a materials recycling facility [MRF] and civic amenity site [CA site] on
land at the Slyfield Industrial Estate, Guildford.
1.2
This statement sets out in
non-technical language a summary of the Environmental Impact Assessment that
accompanies that application.
2. development context
Introduction
2.1 The application
site lies at the eastern end of the Slyfield Industrial Estate, on the northern
outskirts of Guildford. To the west is the residential area of Slyfield Green
and to the east the River Wey, with the A3 beyond. The Guildford sewage
treatment works (STW) lies immediately to the south with land directly to the
north being a former landfill site.
2.2 The application
site is owned partly by Thames Water (TW) and partly by Surrey County Council
(SCC). The SCC land is occupied by a waste transfer station and civic amenity
site. The TW land is vacant and used only for the management of sewage sludge
and the disposal of stormwater from the STW. Access to both sites is off
Moorfield Road. This forms a junction with the A320 Woking Road.
2.3 The TW land is
allocated for employment use within the deposit draft of the Guildford Borough
Local Plan.
The Proposed Development
2.4 The development
will consist of three main parts:
§ An Energy from Waste (EfW) plant;
§ a Materials Recycling Facility (MRF); and
§ a civic amenity facility (CA site) to replace the existing.
There will also be a weighbridge and office together with roads and extensive landscape planting. The layout of the site is shown on Figure 2.3.
Energy
from Waste
2.5 The EfW plant has been designed to treat up
to 225,000 tonnes of household waste a year as part of the Surrey Waste
Management contract. It will consist of:
§ a waste reception hall with six reception bays linked to a storage bunker;
§ a central control room;
§ a two stream grate within which the waste is burnt;
§ a steam turbine and electric alternator to produce the electricity;
§ a two stream gas cleaning system to remove pollutants from the gas given off during burning;
§ a 70 metre high stack (chimney) to disperse gases to the atmosphere; and
§ condensers to cool the exhaust steam and turn it back to water for re-use in the plant.
2.6 The way in
which the plant operates is shown in Figure 2.4.
2.7 Two residues come from the incineration
process;
§ Bottom Ash, of which there will be about 67,500 tonnes a year and which comes from the burning of the waste. This material can be recycled as construction materials; and
§ Fly Ash which comes from the filters used to clean the gas. This amounts to about 13,500 tonnes a year. It is removed in sealed tankers to properly licensed landfill sites.
2.8 The facility
will be equipped with a computer controlled management system, which will
regulate and monitor the operation of the plant and all emissions to the environment.
2.9 The plant itself will operate continuously
but will only take deliveries of waste during normal working hours.
2.10 All the EfW processes are housed in a single
building, providing a more attractive appearance and reducing the potential
nuisance to neighbours. The building is shown in Figure 2.5. It measures about
139 metres by 101 metres and is a maximum of 40 metres high, with the stack
extending to 70 metres.
2.11 The Materials Recovery Facility (MRF) will be
housed in a specially designed building. It will be of an “L” shaped design
measuring 60 x 40 metres and will be located in the north east corner of the
site. It will be a maximum of 12 metres high and have a high quality finish
designed to match the main EfW building. It will cater for a range of
recyclable materials that have been separated by householders from the waste
they throw away in their dustbins. This may include glass, cans, paper and
cardboard, and possibly textiles, plastics and/or other recyclable goods.
Deliveries will take place during normal working hours.
2.12 The civic amenity facility is a direct
replacement for the existing on-site facility. It will have ten containers for receiving
waste and a ramp, up which people will drive to deposit their waste. About half
of this waste will be taken to the EfW plant for burning. It will operate the
same hours as the existing facility.
Traffic
2.13 Despite the increase in the amount of waste
handled, overall traffic flows will increase by less than 7.5 percent, with
weekday lorry movements being no more than at present. All traffic will use the
existing access to the waste transfer site, off Moorfields Road.
Drainage
2.14 Clean water from
roofs will be allowed to soakaway under the main buildings and/or be fed to
three ponds that will be built for landscape and nature conservation reasons in
the south east of the site. Water from roads and other paved areas will be fed
into underground tanks so that any grit or dirt is settled out, before being
discharged into the existing sewer to the River Wey through a petrol and oil
interceptor. Any polluted water, which has been in contact with waste will be
transferred by sewer to the STW for treatment.
Landscaping
2.15 Embankments will be provided on the southern,
western and eastern boundaries to blend the new development into the surrounds,
to provide visual screening and to assist with noise Where appropriate they
will be formed as an extension of existing embankments around the site.
2.16 The three types of new planting proposed
consist of woodland, rough grassland and wetlands with ponds. In addition,
existing woodland located in the east of the site will be retained and
protected. The new planting will compliment the existing woodland vegetation
located along the northern bank of the River Wey and will consist of native
species. As it matures it will help to filter views of the development.
2.17 Rough grasslands
will provided as a potential source of food to the Barn Owl, which have been
identified as feeding on the site. It will be mowed infrequently so as not to
lose its wildlife value.
2.18 Finally, ponds
will be created to provide additional ecological interest within the site.
Rushes will be planted around the margins of the ponds.
Remediation
and Construction
2.19 The remediation of the site and the
construction of the development will take place over a maximum three year
period. The existing transfer station and civic amenity site will continue to
operate during this period.
2.20 A number of
alternatives have been studied including;
§ Alternative options for managing Surrey’s waste
§ Alternative sites for major waste facilities;
§ Alternative designs for the Slyfield site; and
§ Alternative access arrangements.
The option of doing nothing was also considered.
2.21 In terms of
alternative ways of managing Surrey’s waste, the study concluded that recycling
and re-use alone could not cope with the volumes of waste that will be generated
in future. Even if both increase dramatically, there will still need to be some
other form of treating large quantities of waste. Energy from waste is
considered better in this respect than the current system of relying upon
landfill.
2.22 The study then
looked at five possible alternative sites, namely;
§ Charlton Lane, Shepperton;
§ Clockhouse Brickworks, Capel;
§ Copyhold Works, Redhill;
§ Horley Road, Earlsfield and
§ Wisley Airfield.
2.23 All except Capel
are in the Green Belt and so there is a strong presumption in the planning
process against them being used for a major waste facility such as an EfW
plant. Capel is in the countryside beyond the Green Belt and so is also
considered unsuitable to accommodate a large-scale industrial uses. Except for
Charlton Lane, all the sites are a long way from where most of the waste
originates and so will result in thousands of extra miles being travelled by
large lorries each year. Other specific constraints were also found to exist at
each of the sites.
2.24 A range of alternative layouts were tested
for the application site. The selected
option was found to constitute the most appropriate balance between a range of
objectives relating to the way the plant operates, its appearance and the need
to ensure that it does not cause nuisance or damage the environment.
2.25 Finally, four
different ways to access the site were examined.
§ The existing access arrangement via Moorfields Road;
§ Direct access onto the A3 through the formation of a new junction;
§ Formation of a new road linking to Clay Lane in the north west; and
§ Formation of a new route from the A320 via the existing STW.
Of
these the existing access arrangement was found to work best and be safest. The
other three options were either not practical or achievable or caused
environmental or highway problems.
2.26 The option of
doing nothing will not happen in practice as the site is allocated for
employment use. If it were to remain undeveloped, most environmental conditions
would remain unchanged except for ground and groundwater contamination, visual
appearance and ecology. In all cases the current condition of the site is
likely to deteriorate to the detriment of the local environment.
3. planning policy context
3.1 The planning policy
context is set out in national, regional and local plans. The relevant local plans comprise:
§ The Surrey County Structure plan (SSP - 1994);
§ The Guildford Borough Local Plan (GBLP - 1993.); and
§ The Surrey Waste Local Plan (SWLP - 1999).
3.2 Other policy
guidance comprises:
§ National Planning Policy Guidance;
§ Draft Regional Planning Guidance and advice comprising RPG9;
§ The draft Structure and Local Plans; and
§ The National Waste Strategy (Waste Strategy 2000).
3.3 The effect of
the development is assessed against this policy background in the remainder of
the EIA.
4. eia context
4.1 The
environmental impact assessment considers all environmental effects, positive
and negative, arising from site preparation, construction and operation of the
IWMC. It looks at the significance of effects and what measures can be put in
place to offset potentially adverse effects.
5. summary of environmental
impacts
5.1 The following
sections summarise the predicted impacts associated with the proposed development
according to the main topic areas identified.
6. geology, groundWATER and surface water
Introduction
6.1 A site
investigation was carried out to assess ground conditions and the way in which
this affects the groundwater beneath the site. Existing data on the quality of
the River Wey were examined, and samples taken from the surface water drain,
which flows from the Slyfield Industrial Estate into the River Wey. The data
were used to determine surface water quality. Finally, existing data on flood
levels were collected to determine if the site contributed to providing storage
capacity for flood waters.
6.2
The site investigation found made
ground comprising some biodegradable waste and sewage sludge to an average
depth over the site of 1.7 metres. Below this are clayey sand and gravels and
then the London Clay. The volume of sludge across the site is calculated to be
approximately 3,000 m3. Waste materials have been deposited in the
past within the site boundary, at the northern end, as part of landfill
operations on adjoining land.
6.3
Some contamination was found,
particularly from the sewage sludge, where levels of certain pollutants were
found to be higher than normal levels in the environment. This is not
unexpected given that the land has been used for many years for sewage
treatment. However concentrations in the underlying made ground and superficial
deposits were below published standards for land used as parks, playing fields,
gardens or open space. The land is
therefore suitable for accommodating development without requiring remediation.
6.4 Groundwater
quality beneath the site shows low levels of contamination which get worse in
the north, suggesting an effect from the historical landfill activities.
Testing of the soil for gases proved elevated concentrations of methane and
carbon dioxide almost exclusively in areas where sludge has been deposited.
There is little evidence of landfill gas coming into the site from the landfill
to the north.
6.5 In terms of
surface water, the 1 in 100 year flood level has been established for locations
upstream and downstream of the site. These are:
§ At Stoke Mill Farm: 29.21 m aOD (97.28 feet)
§ At Burpham Court Park Farm: 26.88 m aOD (89.50 feet)
6.6 The quality of
the River Wey near to the site is, according to Environment Agency data, shown
to be high. As mentioned above, there is an existing surface water outfall from
the Slyfield Industrial estate into an ox-bow lake, which forms part of the
River Wey. The ox-bow is of much poorer quality.
Construction Impacts
6.7 Due to the
setting of the site and its history of development to date, six possible
impacts on the environment were identified and assessed:
The
loss of flood storage capacity associated with the River Wey
6.8 None of the
land proposed for redevelopment is in the floodplain. This means that the
development would not reduce flood storage capacity locally. Ground levels have
been designed to ensure that no flooding of the site will occur.
A
change in the surface water run-off characteristics of the site during
remediation and construction works
6.9 The possibility
of silt getting washed into rivers always exists when large-scale earthmoving
and construction takes place. To protect against this, all surface water will
be fed into holding ponds to ensure that any sediment is settled out before
clean water passes into the River Wey. As part of the IWMC, a new drainage
system will be installed, taking over from the settlement ponds. This will
include settlement tanks and petrol/oil interceptors to control the quality of
water entering the river.
The
release of contaminants in the soil during site redevelopment
6.10 Moving soils
around the site may “unlock” contaminants and make them more likely to pass
into the groundwater or be released as dust. The level of contamination that
has been identified by the site investigation makes the risk of this occurring
very low. Furthermore, the possible removal from the site of 30,000 m3of
the most polluting material will mean that the long-term likelihood of
pollutants passing to groundwater is significantly reduced.
6.11
The risk of contamination will be
minimised by ensuring that the area of ground disturbed at any one time is as
small as possible and by adopting stringent dust control measures which will be
set down and agreed with the Guildford Borough Council in a “Code of Construction Practice”
Excavation
into the groundwater
6.12 Excavations in
some parts of the site will take place below groundwater. Some groundwater may
be polluted Without adequate controls in place, groundwater may be polluted
accidentally by spillage. Risks will be minimised by installing temporary sheet
piling to reduce the volume of groundwater that enters the excavations.
Polluted groundwater that does enter the excavation will be pumped to the
adjacent STW for treatment. Groundwater will be monitored throughout operations
to check its quality.
Damage
to the ecological buffer zone along the River Wey corridor
6.13 The ecological
buffer is outside the application site and will not be directly affected by the
development. It is important, however, to ensure that it will not be
accidentally affected during construction. A stand-off zone will, therefore, be
set up to make sure that damage does not occur. Only the raising of the landscaped
embankment and the planting of trees will occur within this area. Both will be
strictly controlled.
A
loss of soakaway capacity at the adjoining Guildford STW during storm events
6.14 Part of the site
is currently used by Thames Water as a stormwater overflow. The development
proposals will take away this facility. Two factors will ensure that the
proposed IWMC will not cause a problem with soakaway capacity: the availability
of other Thames Water operational land adjacent to the development site and the
potential for process changes at the STW.
Operational Impacts
6.15 The main risks
to the surrounding water environment once the facility is operating will occur
through:
§ run-off of water from external areas of waste handling (i.e. the Civic Amenity site);
§ the potential for spillage of contaminating materials at the site during the period of operation;
§ the potential for the discharge of fire water run-off into the River Wey during a fire at the site; or
§ the change in run-off characteristics of the site surface due to the construction of hardstandings, roofs and pavements.
All four will be dealt with through the installation of an
appropriate drainage system.
6.16 Foul and
polluted water will be collected and discharged to the Guildford STW for
treatment Clean water from roofs will be drained to soakaways or to the three
“ecological” ponds described earlier.
6.17
The remaining water, including drainage
from roads and paved areas will be drained to holding/settlement tanks and
discharged to the River Wey using the existing surface drain from the Slyfield
Industrial Estate. The drain will be
improved to handle the extra volume. A control valve will be fitted to this
system and closed off in the event of emergency or spillage.
6.18 Groundwater
monitoring will be undertaken throughout the construction period to ensure that
no deterioration in quality occurs that might affect the River Wey. Surface
water monitoring will be undertaken upstream and downstream of the site to
check for adverse effects. Finally, monitoring of soil gas concentrations will
be undertaken during and following the removal of sludge material.
6.19 The groundwater,
surface water and soil gas monitoring programmes described above will be
continued into the operating period of the plant in order to confirm that there
is no long term impact on the water environment.
7. waste management
Introduction
7.1 Three possible
impacts were assessed under this Section;
§ the need to remove spoil or contaminated soils from the site in connection with land remediation and plant construction;
§ the effect of the development upon the management of household, commercial and industrial waste within Surrey; and
§ the disposal of ash from the EfW plant.
7.2 The volume of
non-inert waste that is generated within Surrey is shown on the following
table.
|
Table 7.1 Surrey Waste Arisings (million tonnes) |
||
Surrey Scenario |
1998 Base Year |
Cumulative 1998 – 2010 |
Household Waste |
0.338 |
5.278 |
Commercial and Industrial Waste |
0.561 |
6.943 |
Civic Amenity Waste |
0.124 |
1.770 |
Total |
1.023 |
13.991 |
7.3
Surrey also receives waste from, and
sends its waste to, other Counties. If
this waste is added in, it means that Surrey will need to treat or dispose of
over 18 million tonnes of non-inert waste between 1998 and 2010.
7.4
Some of this can be done through
recycling. At the moment, only 9 percent of household waste is recycled. Even
if recycling reaches a rate of 25% in line with the target in the Surrey Waste Management
contract, it will still leave over 1 million tonnes of waste a year needing to
be treated or disposed of by other means.
7.5
Landfill is the only other major option
for dealing with large volumes of waste. This will not be able to take
untreated waste at current levels once the European Landfill Directive takes
effect. So some other form of treatment would be necessary. Also, available
space in landfill sites is rapidly running out. Capacity for only about 8.4
million tonnes of non-inert waste existed in permitted landfill sites in 1999
and some of this may not now be usable. Whilst some new sites may be permitted,
it is not likely that they can take all the waste requiring disposal up to 2010
let alone beyond this date. The estimated shortfall in landfill capacity,
taking account of increases in recycling, but assuming all other things stay
the same, will amount to space for about 6 million tonnes of waste.
Construction Impacts
7.6
The only impact during the construction
stage comes from the need to remove up to 30,000 m3 of waste. Some
of this will need to be taken off site to landfill. The rest, however, can be
sorted on site and re-used where appropriate, such as in constructing
landscaped embankments.
7.7
There will not be any disruption to
existing waste management operations and facilities within Guildford as a
result of the switch from waste transfer, using the existing transfer station,
to the recovery of energy from waste through a new EfW and Materials Recycling
Facility.
Operational Impacts
7.8 The development
will result in two main long-term impacts associated with the operation of the
IWMC:
§ A major shift in the management of waste within Surrey through the diversion of non-inert waste from landfill into recycling and energy recovery; and
§ A requirement to manage the residues from the combustion process.
7.9
The first of these represents a major
benefit of the development proposals. On its own, the new IWMC will result in a
significant increase in both recycling and the recovery of value from waste
through the production of energy. Currently 91% of Surrey’s non-inert waste is
landfilled. This will reduce to 58% when the IWMC is in full operation and, if
the ash is recycled, to only 44%.
7.10
In practice, the plant will not be the
only change in waste management within Surrey. It will form part of a
comprehensive strategy for managing waste. As part of this wider strategy it
will play a major part in reducing the volume of waste going to landfill to
only 14%. With associated increases in recycling and energy recovery, this
would exceed all Government and County targets for the management of waste.
These targets are:
§ To achieve 45% recovery by 2010;
§ Within this recovery figure, to achieve 30% recycling by 2010.
Residue Disposal
7.11 The process
gives rise to ash that needs to be disposed of. The overall strategy for Surrey
includes facilities for recycling bottom ash to make construction materials. Fly
ash will need to be sent to landfill. Although this represents a slight adverse
effect, this has to be seen in the overall context of the strategy, which
reduces the amount of non-inert waste being sent to landfill from 91%to only
14%.
Mitigation Measures
7.12 To minimise adverse effects from the
development the following measures will be employed:
§ Re-use as much material on site as possible whilst ensuring that all material that needs to be removed is taken safely to appropriate landfill facilities;
§ Maintain an efficient combustion process to ensure that the volume of ash is kept to a minimum;
§ Where material has to be transported off-site, to use the closest suitable facility; and
§ Reprocess the ash residue where possible.
8. ecology and nature conservation
Introduction
8.1 The River Wey
and its associated floodplain are of high conservation value, due to its
location and the species it supports. Parts are formally designated as Sites of
Nature Conservation Interest.
8.2
Land between the site and the Wey contains
alder woodland and other more scrubby areas containing elder, nettles and giant
hogweed. Many of these trees are dying although they still have some nature
conservation value for lichens, fungi and use by animals.
8.3
The site itself, however, has been used
for the management of sewage sludge from the adjacent STW for at least twenty
years. As a result, some contaminants are higher than would normally be
apparent in the environment. Some
contaminants have the potential to harm the development of plant communities
and affect amphibians. It therefore supports mainly transient plants and few
animals.
8.4
Along the north eastern boundary, there
are some reasonably mature broad-leaved trees. More mature plant communities
were also found to exist both on the sludge lagoons and the surrounding drier
land, but no species of importance were noted. Overall, the diversity of plant
life is poor, being largely dominated by coarse, vigorous plant species. Most
diversity occurs outside the site boundaries, where vegetation is less
disturbed.
8.5
Few mammals were recorded on the site,
due to the nature and duration of disturbance and the nature of the made
ground. It is likely that bats forage over the site, roosting in adjacent
trees.
8.6
A reasonable number of species of bird
have been recorded on the site. The most significant of which is the barn owl,
which was recorded as foraging over the site, but not nesting or breeding.
8.7
Reed bunting was also seen foraging on the
site and are likely to be associated with the extensive marshland on the
opposite bank of the river. Other seed-eating birds also feeding on the site
include goldfinch, chaffinch and house sparrow.
8.8 In summary, the
site has been subject to continuous disturbance and deposition of sewage
sludge. The habitats found on site are common and are not of real conservation
value. However, their location near high quality habitat does increase their
potential contribution towards local biodiversity.
Construction Impacts
8.8
Construction activity will lead to the
direct loss of the habitats on site, except for the stand of woodland at the
northern end. This will, however, be disturbed in part as a result of the need
to upgrade the surface water drain.
8.9
The loss of foraging for barn owls,
even for a temporary period, is a potentially undesirable effect of
development. However, the limited contribution of the site to their feeding
requirements means it is unlikely to be important. The final design for the site
makes specific provision for foraging areas and perches for barn owls and so
will improve the position in the medium and long terms.
8.10 Species
such as reed bunting, snipe, green woodpecker, goldfinch, blackbird, dunnock
and starling will lose some foraging habitat. Of these, only blackbird and
dunnock are likely to nest on the site. Both foraging and nesting will,
however, return after construction and so any effect is only temporary.
8.11 Construction
operations will result in increased noise and human activity and this may cause
disturbance to birds and animals. However, those on site or nearby will already
be accustomed to noise from the WTS and CA site and hence the effect will not
be significant. Vibration associated with construction is predicted to be of a
similar level to normal footfalls at the River Wey and so again will have no
detrimental consequences. Retention of the corridor along the bank of the River
will ensure that no important wildlife corridors are affected.
8.12 The most
important impact from the operation of the IWMC stems from possible air
pollution effects. It may effect ecology through:
§ Direct deposition of pollutants on leaves or soil;
§ Deposition of pollutants on soil or water leading to build-up in the habitat; and
§ Contribution to acid rain.
8.13 Predicted
emissions from the EfW plant are extremely low and are well within guideline
levels and so there is no evidence to suggest that harm will be caused to plant
or animal communities as a result.
8.14
In terms of important or sensitive
areas, there are 16 Sites of Special Scientific Interest within 10km of the
proposed site. Of these, only Whitmoor Common SSSI lies within the zone where
the deposit of pollutants is likely. It lies at the extreme edge of this zone
and so any impacts are likely to be negligible. However, there may be a slight
increase in deposition of pollutants, which over time could lead to
acidification of both the heathland and in particular Britton Pond.
8.15 Lichens
are particularly sensitive to changes in air pollution levels and there may be
an effect on them even though emissions from the plant are very low. Again,
however, three is no evidence avialable that this will be the case.
Mitigation Measures
8.16
Overall, the effects on ecology are not
significant. Indeed the removal of contaminants from the site is likely to have
a beneficial effect on surrounding habitats. However, it is still possible to
improve ecological interest as a result of the development. The main measures
proposed are;
§ Providing grassland areas and perches for foraging Barn Owls;
§ Creation of three new pond areas as permanent aquatic habitats; and
§ Landscaped planting designed to be sympathetic to ecology needs.
8.17 In addition, it
may be possible with the agreement of the landowners to improve the Ox-bow lake
to the north east of the site in association with the provision of new site
drainage. Although not necessary to offset the effects of development, it does
represent a chance to contribute to enhancing ecological habitats in the area.
Introduction
9.1 The main tool used to assess the air
quality effects of the development is that of dispersion modelling. This
predicts the concentration of pollutants given out by the EfW plant and, based
upon chimney height and “worst case” weather conditions, how these will be
dispersed in the atmosphere. Other effects looked at include dust from
construction activities and emissions from traffic.
Construction
Impacts
9.2
The main air quality issue during the
construction phase is the generation of dust through remediation and
construction operations. These impacts are no different to those experienced
with any major construction project and are easy to control using well
established construction management techniques.
9.3
Impacts will be controlled through a
“Code of Construction Practice” which will be prepared and agreed with the
Guildford Borough Council before works start on site.
Operational
Impacts
9.4
The main pollutants released into the atmosphere
from the process will be combustion products, such as carbon dioxide, sulphur
dioxide and nitrogen dioxide. In all cases, the level and concentration given
off are well within emission regulation limits laid down by the European
Parliament and implemented by UK law. For example, the level of sulphur dioxide
given off represents only 0.6 percent of the relevant air quality standard. The
comparable figure for nitrogen dioxide is 3.8 percent. For dioxins and furans
the figure is as low as 0.03 percent.
9.5 The results of dispersion modelling for all
pollutants indicate that the design of the plant will ensure that any emissions
from the stack are harmless.
9.6 Carbon dioxide is not harmful to health but
is a greenhouse gas. The use of EfW will result in an overall decrease of CO2
emissions to air by reducing the burning of fossil fuels to generate
electricity and the production of methane from landfill sites.
9.7 The level of change in traffic on the roads
as a result of the development is negligible. So, therefore, are the potential
air quality impacts. The assessment shows traffic will have no significant
impact on background air quality concentrations.
9.8 As well as simply looking at emissions from
the plant itself, the assessment also looked at the cumulative effect; that is
the existing background concentrations in combination with the additional
contributions from traffic and process emissions. This found that pollutant
levels remained well within the relevant emissions standards.
9.9 The air quality assessment also looked at
the health effects of the long-term operation of the plant. In summary, it
found that the potential impacts of the IWMC operation on the health of the
local population, even under a worst case scenario of lifetime exposure, would
not be significant. In all cases, the worst case daily intake of contaminants
would remain well below that which occurs naturally in the UK population from
background sources.
Introduction
10.1 Noise surveys
were carried out in the area to establish existing background noise levels in
order to compare these with forecasts for the proposed development. As the EfW
plant will operate on a continual basis, readings were taken for day and
night-time.
10.2 These surveys
found that the area is relatively noisy due to the proximity of the A3. It is
likely that traffic will increase rather than decrease in the future and there
is likely, therefore, to be a gradual increase in background noise level for
the area. Local traffic within the estate is also likely to grow and add to
this.
Construction
Impacts
10.3
Most construction operations do not
generate large amounts of noise and would rarely be heard at nearby houses.
Piling will be required, however, and would give rise to vibration. This will
not be felt at the nearest houses. The noise from pile driving is likely to be
heard but will be below the level that Surrey County Council have specified in
the guidelines for temporary operations and well below the limit normally
accepted for construction and demolition noise.
10.4 This will be
controlled through a “Code of Construction Practice” which will be prepared and
agreed with the Guildford Borough Council before works start on site.
10.4
The temporary increase in vehicle
movements during construction is well below the level at which the Department
of the Environment, Transport and the Regions would require assessment.
Operational
Impacts
10.6 Noise sources
within the plant need to be considered during both day and night as the plant
will need to operate continuously. Other sources such as vehicle deliveries and
the operation of the CA site will only take place during the day.
10.7 No operational
site activities will generate vibration that would be felt outside of the site
boundary.
10.8
To meet SCC guidelines, the plant has
been designed to ensure that the noise levels generated are below the level
that could be heard at the nearest housing at the quietest part of the night or
day. This has meant placing many of the noisier operations inside a single
building and using silencing on other parts of the process. This applies to the
fans and condensers needed to cool the air and draw it up through the stack for
high level dispersion.
10.9
As a result of employing these
measures, the worst case noise prediction falls below the SCC criteria for
night-time noise, meaning that the plant will not be heard at the nearest
houses. In practice, noise levels will be lower than predicted.
10.10 The changes in
traffic flow on all roads as a result of the development are well below the
level at which the Department of the Environment, Transport and the Regions and
the Institute of Environmental Assessment considers an assessment is normally
required. For all of the roads, the
changes in noise level are negligible and hence no noise level increase would
be noticeable.
11.
traffic & transportation
Introduction
11.1
The proposed access for the new
development is the same as for the existing WTS and CA site, namely off the
A320 via Moorfield Road. A comparison was therefore undertaken to assess
whether the development would increase the levels of traffic on these roads,
and if so whether that increase would have any adverse effects.
11.2
The existing waste transfer operations
generate on average 1,320 heavy goods vehicle movements during weekdays and 34
on Saturdays. These figures were obtained from traffic counts. In addition
there are cars visiting the CA site.
Peak hour flows for weekdays, which is when most traffic on the roads
occurs show only 19 movements in the morning and 2 in the evening.
11.3
The survey demonstrated that queues
occur along Woking Road during peak hours, particularly between the Moorfield
Road and Hazel Avenue, however, this will improve with the installation of
traffic lights at the Moorfield Road junction.
Construction Impacts
11.4 With the
possible exception of the major concrete pour, the construction phases will not
result in any material increase in the levels of heavy goods traffic on the
local highway network. The worst phase was assessed to determine the affect
upon queues during peak hours and was found to have no significant effect, with
a 2.5 percent increase in traffic during morning and evening peaks on Moorfield
Road itself and only 1 percent on the A320 southbound. This phase will in any event last for a
maximum of only 8 months.
11.4
It is estimated that when fully
operational the development will generate 1,280 heavy goods vehicle movements
during weekdays with a total of 84 on Saturdays. The weekday totals equate to
the volume of heavy goods vehicle traffic currently visiting the site. An
increase in the workforce will mean corresponding increases in car movements of
30 movements per day but this will have no effect upon the operation of the
road system. The number of Saturday movements will increase by 66 of which 16
will be cars and the remainder heavy goods vehicles. This again is not significant
in terms of the operation of surrounding roads.
11.5
In terms of the peak flows, the morning
weekday peak will increase by only 3 movements, whereas the evening peak will
decrease by 2 movements with no projected movements occurring.
11.6 In conclusion,
the site access will experience a slightly higher level of traffic on a
Saturday, however, this is not considered to represent a material impact for a
junction that does not suffer any congestion or queuing. Operations will not
lead to a worsening of the situation on the A320 due to the minimal increase in
vehicle movements forecast. A lorry routing agreement will be entered into to
make sure Heavy Goods Vehicles use only the major routes and this will
represent a gain as a result of the development.
12.
cultural heritage
Introduction
12.1
Cultural Heritage covers both
archaeology and the possible effects on the conservation area of the River Wey.
12.2
Archaeological interest was assessed by
looking at a wide range of records, including old maps, and by studying aerial
photographs. The records show a number of archaeological finds within the area
of the application site from neolithic, bronze age, iron age and Roman periods.
No archaeological features were discernible in any of the aerial photographs studied.
12.3
The River Wey conservation area was
designated as recently as 1999 and is tightly drawn to include only the
navigation itself, the towpath and important structures alongside it.
Construction
Impacts
12.4
Any excavation and movement of sludge
and soil during construction may cause potential damage or destruction to any
surviving archaeological features or deposits or finds which may exist within
the site. However, it is possible that such damage has already occurred during
the original construction of the sludge beds.
12.5
Field evaluation in the form of trial
trenching or a watching brief will therefore be undertaken during construction
works. The advice of Surrey County Council Archaeology Section will be sought
in establishing the scope and specification of further archaeological work.
Operational
Impact
12.6
There are no anticipated effects to
archaeological deposits from operations on the site.
12.7
The character of the River Wey
corridor, and hence its interest, is not dependant upon views over the
application site. Furthermore, it is compromised near to the site by the effect
of the A3, pylon lines and the industrial estate itself. Therefore the
development will not cause harm to the setting of the conservation area.
13. socio – economic effects
Introduction
13.1 The development
will result in the creation of both temporary construction jobs and increased
levels of permanent employment on the site with around 55 new jobs being
created.
13.2
In terms of construction employment, beneficial
effects will occur over the three years that the development will take to
build. The maximum number of construction workers forecast to be working on
site in any one month is around 320. The average number of workers on site
during the construction phase will be 135 workers.
13.3
The development will increase
employment over ten fold compared with the existing waste transfer operation.
It will require a range of skills and the operators will offer training to help
provide appropriate skills to people within the local labour market.
14. land use, recreation and amenity
Introduction
Construction
Impacts
14.3 The local community will be slightly affected
by construction operations although the use of a strict “Code of Construction
Practice” which is enforced by the Borough Council will ensure that no
significant effects occur. There will be no direct effects on the community
such as loss of existing facilities. All effects that are felt will therefore
be indirect, limited and temporary.
Operational Impacts
14.4 The development
will not require the closure or removal of any existing facilities although
once the IWMC is completed, the existing WTS and CA facilities will no longer
be required and could be removed from site.
14.5 The development
accords with the planning policy in the Surrey County Structure Plan, the
Guildford Borough Local Plan and the Surrey Waste Local Plan and therefore
represents an appropriate use of the application site.
14.6
The development will be visible from
some sections of the towpath, the River Wey and the Riverside Park and may
therefore reduce some peoples’ enjoyment of these areas albeit not by a great
deal. Other footpaths will not be similarly effected as they are already much
closer to the industrial estate and have clear views of it.
14.7
Existing uses on the estate will not be
affected as the development is a replacement for the existing WTS and CA
facility in a similar location and of an improved appearance.
15. landscape and visual
assessment
Introduction
15.1
The effect of the IWMC on both the
local landscape and on views from important viewpoints forms an important part
of the environmental assessment.
15.2
A balloon was flown over the site,
representing the height of the stack and photographs taken from a wide area of
Guildford and its surrounds to assess how visible the plant would be. This
enabled a computer image of the plant to be accurately positioned within
photographs in order that its effect from key viewpoints could be seen.
15.3
The site is described by the Countryside
Agency as part of the “Thames Basin Heath” landscape which is characterised as
a diverse landscape with open, rolling heathland and conifer woods providing
some unity. Heavily populated areas also exist with development focussed in
transport corridors. River valleys are broad with gently rising sides and a
complex pattern of canals, ditches and channels with undrained areas in the
valley bottoms.
15.4
The site takes its character from the
series of sludge lagoons and treated sewage spoil heaps, which dominate the
site. Most of the mature vegetation is on land around the site, not the site
itself.
15.5
The site is also influenced by the
character of the industrial estate and the River Corridor. These are in marked
contrast to each other. The estate is generally unattractive with no overall
theme and dominated by clutter such as parked cars, open storage, signage etc.
Some improvement has been achieved through new developments and the Borough
Council is keen to see further improvements to the estate as a whole.
15.6
The River corridor is generally
attractive with an enclosed feel resulting from mature trees that prevent long
distance views. There is considerable
ecological interest, mainly to the east of the river, with extensive reed beds,
open water and unimproved grassland. The landscape quality is affected,
however, by the A3, the electricity pylons and the industrial estate.
Construction Impacts
15.7 Any impacts
during the construction phase will be temporary but will tend to have an
adverse effect whist they last.
Operational Impacts
15.8 Guildford’s
urban form is of low-rise development interspersed with large built forms
including the cathedral, the shopping centre, the university and the leisure
centre. The development will be in
keeping with this landscape forming an additional large built form on the urban
fringe adjacent to an industrial estate.
15.9 The smart design
and high quality materials used for the new plant will actually result in an
improvement of the local character of the industrial estate. Whilst it will be
more visible than the existing WTS and CA facility, the use of curves in the
design of the building, particularly within the stack, will make it look less
industrial and therefore will be seen as a more attractive element in views.
15.10 The plant will
also assist more local views, with the current derelict appearance not only of
the site itself but also of the existing WTS and CA facilities giving way to a
modern landscaped development.
15.11 The landscape
character of the river corridor is protected by the existing belt of trees
which provides screening of the site and enclosure of the river. The tree belt
will be reinforced by new screen planting within the site. Therefore the effect
of the development on the River Corridor will be low.
15.12 Views from
surrounding housing areas will vary, with most being obscured by other houses
and vegetation. It is likely therefore that the EfW plant will only be glimpsed
from the majority of locations within existing estates.
15.13 In summary, the
form of the building, site layout, the use of landscaped embankments and the
extensive planting of native trees all contribute to reducing the visibility of
the development. The IWMC will not therefore adversely affect the landscape
character of the area or the quality of the landscape. Neither will it result
in unacceptable levels of visual intrusion in either the night or day.