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CONTENTS
1. Executive Summary 1
Scope and Method 1
Conclusions 2
Recommendations 3
2. The Background to This Study 6
The Key Issues 6
The Policy and Planning Background 7
Previous Technical Studies which led to this
Report 8
The Scope of this Study 9
3. The Main Reasons for Considering
Alternatives 12
Coastal Change 12
Sustainability 12
4. The Methodology for This Study 16
Introductory Comments 16
Identifying Alternative Patterns of Supply 16
Selecting and Assessing Representative
Sources and Sites 17
Comparing the Relative Sustainability of
Alternative Patterns of Supply 19
5. The Current Pattern of Supply and Demand 20
Sand Dredged from the Bristol Channel 20
Aggregate Quarried within South East Wales 23
Aggregate Imported from outside South East
Wales 24
Secondary and Recycled Materials 24
Demand for Aggregate in South East Wales 26
Summary of the Current Pattern of Supply and
Demand 27
6. Potential Alternative Patterns of Supply and
Demand 32
Alternative Sources of Aggregate not
Currently Exploited 32
Three Potential Alternative Patterns of
Supply 38
The Differences between the Current and
Alternative Patterns of Supply 46
7. The Selection and Assessment of
Representative Sites 48
Choosing a Set of Representative Sites 48
Assessing the Chosen Sites 50
How the Case Studies Contribute to the
Patterns of Supply 51
8. The Comparative Sustainability of
Alternative Patterns of Supply 54
Description of the Sustainability Assessment
Process 54
Pattern of Supply No. 2 Compared to the
Current Pattern (No. 1) 54
Pattern of Supply No. 3 Compared to the
Current Pattern (No. 1) 56
Pattern of Supply No. 4 Compared to the
Current Pattern (No. 1) 58
Conclusions from the Sustainability
Assessment Process 61
9. Discussion, Conclusions and Recommendations 64
Discussion 64
Conclusions 66
Recommendations 67
Appendix 1 Research
Specification and Steering Group
Appendix 2 Supply
Option Fact Sheets
Appendix 3 Site
Assessment Check List
Appendix 4 Sustainability
Assessment Model
Appendix 5 Coastal
Change Issues
Appendix 6 Energy
Issues
Appendix 7 Noise
Issues
Appendix 8 Traffic
Issues
Appendix 9 12
Case Studies
Appendix 10 Sustainability
Assessment, Patterns of Supply No. 2 vs No. 1
Appendix 11 Sustainability
Assessment, Patterns of Supply No. 3 vs No. 1
Appendix 12 Sustainability
Assessment, Patterns of Supply No. 4 vs No. 1
1.
Executive Summary
Scope and Method
1.1
This report was commissioned in
May 2001 by the National Assembly for Wales
(the Assembly).
The report is required as an aid to policy making, and in particular to assist
in the difficult choice between continuing to dredge sand from the Bristol
Channel or starting to quarry sand and gravel from potential land-based
resources.
1.2
It addresses the uncertainties
that surround dredging, and specifically the question of whether (and how)
dredging sand from offshore sandbanks affects the beaches of South East Wales.
Drawing on the findings of a more detailed, new interpretative report by
Pethick and Thompson (2002), produced as part of this study, it concludes that,
while no significant impacts on the coastline have yet been detected, some
dredging, in particular from Nash Bank, may in future have effects on nearby
beaches and the wider sediment environment. It therefore recommends that
dredging from Nash Bank should be phased out over a period of 5 to 10 years.
1.3
Because of the high quality of
the sand which is dredged from the Bristol
Channel, replacing it from other sources
will be neither easy nor cost-free. The report builds on earlier work
undertaken by Symonds to identify potential land-based sand and gravel
resources, and compares the overall sustainability (environmental, social and
economic) impacts of switching part of the pattern of aggregate supply away
from dredging to these and other alternative sources.
1.4
It does this by considering a
range of policy scenarios, and the ways in which aggregates suppliers and users
might be expected to respond to each one. All practical potential sources of
primary, secondary and recycled aggregate are considered.
1.5
The option of stopping current
dredging from near to the shore without licensing alternative sources of either
dredged or quarried aggregate is assessed as part of this process, but that
option is not preferred. The penalties are considered to outweigh the benefits.
In particular, the impact of removing so much high quality sand from the market
without making alternative provision is felt likely to generate clear and
damaging social and economic impacts which do not adequately compensate for the
environmental gains, particularly when compared with the alternative
approaches. Utilisation of secondary materials (such as china clay sand and
crushed rock sand) would be maximised, but at the cost of considerably greater
energy consumption (and therefore increased emissions of greenhouse gases). The
use of imported materials would also result in the export of some environmental
impacts.
1.6
A less drastic approach, of
withdrawing all nearshore dredging licences and replacing them with matching
licences from further offshore, is also considered. This has the advantage that
the disruption to the aggregate market would be reduced (especially if phased
in over a period of time). The environmental gains would also be fewer (though
not insignificant), and they would be won at the cost of some additional energy
consumption.
1.7
An alternative approach, which
would also require phasing-in over a period of 5 to 10 years, is also
considered. This would involve shifting dredging further offshore, but reducing
the overall tonnage that is taken. This would be accompanied by limited
exploitation of land-based sand and gravel within South East Wales. It is the
timescale for proving individual resources and gaining planning consent for their
extraction that would require a considerable phase-in period.
1.8
These various approaches (which
are intended to be instructive examples rather than recommended scenarios) are
investigated by assessing a broad range of impacts on a balanced group of
generally representative sites. Some of these sites are real (i.e. current
activities at actual locations), while others are theoretical (e.g. locations
where potential land-based resources might be exploited in future).
1.9
The selection of potential
sources of supply, and the sites chosen to represent each option, were guided
by a project Steering Group,
whose help and guidance are gratefully acknowledged. Industry members of the
Steering Group were actively involved in hosting many of the site visits which
were central to the assessment procedure.
1.10
The report reaches the
following conclusions:
Conclusions
(i)
The policy prescriptions within
'Marine Aggregate Dredging Policy, South Wales' (MADP) are generally prudent,
even though the evidence contained in this study points towards a slightly
different interpretation of some of the facts compared to that which has
obtained before.
(ii)
There is evidence of sediment
transport links between offshore sandbanks within some parts of the Bristol Channel and the beaches
of South East Wales. The links are generally weak, however, and do not imply
that dredging will inevitably have impacts on the beaches. The exception is
Nash Bank where it is clear that dredging cannot continue indefinitely without
eventually giving rise to localised impacts on the adjoining coast. No such
impacts have yet been detected, and none are anticipated in the short to medium
term, but it would be prudent to phase out the current operations here over the
next 5 to 10 years.
(iii)
The cases of Nash and Helwick
Banks are not directly comparable. Of the two, Nash Bank is far less resilient,
because of its location in an area of very high rates of potential sediment
transport, and relatively small rates of natural replenishment. Helwick Bank,
by comparison, is located within an area of much greater sediment availability,
where changes can be buffered by the input of sediment from Carmarthen Bay, without
adverse effects on the beaches.
(iv)
Over the last decade, Nash Bank
has been losing volume at a rate that is higher than can be accounted for by
dredging alone, and at current levels of shrinkage could be eliminated
altogether within a period of 90 to 215 years. Long before that point it would
cease to function as an effective breakwater, and impacts would then be felt on
the adjacent shoreline. Alternatives to Nash, as an important source of high
quality fine aggregate, therefore do need to be found.
(v)
Most of the potential
alternatives have very real practical and environmental costs attached to them.
Secondary materials like china clay sand and crushed rock sand significantly
increase the demand for water and cement in concrete (thereby increasing fossil
fuel consumption and emissions of greenhouse gases), and recycled materials
generally offer no effective substitute for sand (as opposed to coarse
aggregate).
(vi)
Good quality land-won sand and
gravel deposits offer far greater potential in all of these respects, but also
have inevitable impacts on landscape, ecology and the water environment (in
particular). These, however, could largely be mitigated, through a combination
of careful location and implementation of best working practices.
(vii)
Irrespective of environmental
considerations, there is no real chance that all of the marine-dredged sand
currently landed in South East Wales could be replaced, (even drawing on all
realistic alternative sources of supply), without raising the cost and reducing
the quality of construction. This would have definite adverse economic
consequences for the region, and would not be justified on sustainability
grounds. It would also result in environmental impacts being exported.
(viii)
Subject to detailed technical
assessments of individual prospects being carried out to prove their quality,
it should, however, be possible to replace a proportion of the marine-dredged
sand by land-won alternatives. Providing that the associated environmental
impacts were adequately mitigated, a partial substitution of marine sand with
land-won alternatives would provide a more sustainable pattern of supply than
that which exists as present.
(ix)
Overall, however, this study
has indicated that the clearest increase in sustainability would be achieved by
a gradual shift of dredging operations from inshore areas (particularly Nash
Bank) to other areas further offshore and/or further west. This conclusion is
subject to the findings of ongoing and future site-specific environmental
assessments at the alternative dredging sites. It would be imprudent,
therefore, to rule out the future need for land based sand and gravel
resources.
(x)
There is a strong economic case
for avoiding precipitate change. Any of the alternative policy scenarios that
have been considered could be phased in over a transition period, and clear
policy statements of intent, tied to a clear timetable, will encourage more
efficient and less disruptive market changes.
Recommendations
1.11
The recommendations that flow
from the above conclusions are as follows.
(i)
Consideration should be given
to amending MADP to steer dredging further west along the Bristol Channel and, more
specifically, to phase out dredging on Nash Bank over a period of 5 to 10
years. This could be achieved by giving notice that, within a minimum of 5 and
a maximum of 10 years, sediment cell CBC1 (which includes Nash Bank) will be
re-classified as a Policy 3 area; and that (more immediately) sediment cell
IBC2 (which includes Culver Sands) will be re-classified as a Policy 2 area.
Further independent research on the geomorphology and sediment dynamics of
Culver Bank (not carried out in the present study) might demonstrate that the
latter suggestion is unnecessary, but in the absence of such work, a
precautionary approach is warranted.
(ii)
Other things being equal, and
subject to appropriate consideration of more detailed and ongoing technical
studies, continued dredging on Helwick bank and new dredging proposals for the
Nobel Banks area should be viewed favourably unless and until new evidence is
found of adverse environmental impacts that can reasonably be linked to these
operations.
(iii)
Until such time as it is
modified in the light of unequivocal new evidence, the conceptual model
developed for this study by Pethick & Thompson (2002) should be used by the
Assembly as a context for the evaluation of future dredging applications and
for establishing monitoring requirements to be attached to future licenses.
These requirements should include full, three-dimensional analysis of
bathymetric changes on both licensed areas and adjoining beaches / sand bodies.
(iv)
As noted in 'Mineral Planning
Policy Wales' (MPPW) and stated clearly in the draft 'Aggregates Technical
Advice Note' (Aggregates TAN), Mineral Planning Authorities (MPAs) should, as a
matter or urgency, safeguard significant areas of potential land-based sand and
gravel resources (as identified in the earlier Symonds report) until such time
as these are either exploited or proved by detailed investigations to be
technically unsuitable.
(v)
In anticipation of the need for
at least some land-won sand and gravel in future years, the Aggregates TAN
should provide mineral operators with a positive signal that well-founded
applications for extraction within appropriate (generally unconstrained)
locations will be given favourable consideration. This could take the form of
‘Provisional Preferred Areas’ as outlined in the earlier Symonds report on land-based
extraction.
(vi)
The Assembly and the South
Wales Regional Aggregate Working Party should establish a mechanism for keeping
future supply options under review. As well as monitoring the effects of marine
dredging, it should monitor the progress of technical investigations of
potential land-based and secondary aggregate resources, to determine the extent
to which these can be relied upon, if and when required. Depending on the
findings of such reviews, future policy options may need to be revised.
(vii)
To the extent that specific
applications can be identified for the use of secondary aggregates such as
crushed rock sand and china clay sand in place of primary aggregates, without
giving rise to greater environmental impacts overall, the Assembly and Local Planning
Authorities should look favourably on any proposals to develop facilities for
the import of such materials into South East Wales by sea or rail.
(viii)
The South Wales Regional
Aggregate Working Party and/or individual MPAs should carry out at least preliminary
desk studies to seek to identify any significant stores of foundry sand in
South East Wales in order to establish whether such a material offers a
realistic alternative to primary aggregate.
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The Key Issues
2.1
Aggregates are crucial to
society, contributing essential components to housing, commerce, industry,
health and leisure facilities, the transport infrastructure and many other
facets of modern life. This Study has been prompted by three main
considerations central to the supply of aggregates to South East Wales, namely:
(i)
the continuing uncertainty that
surrounds the long-term effects of dredging for sand in the Bristol Channel, on which South
East Wales is highly dependent;
(ii)
a desire to achieve reasonable
long-term security of supply as far as aggregate in South East Wales is
concerned, even if that means considering the exploitation of land-based
sources; and
(iii)
the importance which the Welsh
Assembly Government (the Assembly) places on sustainability right across the
spectrum of policy issues.
2.2
For several years South East
Wales has relied heavily on the Bristol
Channel for its sand, and more heavily on
dredged sand than any other part of the UK. Many
millions of tonnes of material have been removed, predominantly from sand banks
relatively close to the shore. Over recent years local residents and interest
groups have become increasingly concerned that changes which they have observed
along the shoreline, affecting both beaches and cliffs, might be linked in some
way to this dredging activity. This concern has created pressure on the
Assembly to review its historic policy of supporting the granting of further
licences to dredge. Most of the licences concerned are actually issued by the
Crown Estate, which owns the sea bed below the low tide mark. Crown Estate
decisions take into account of the Government View, which in this case is the
view of the Assembly.
2.3
Set against this pressure to
stop dredging is the fact that long-term reliance on marine sand has made it
possible for each individual Mineral Planning Authority (MPA) in South East
Wales to adopt what is essentially a presumption against land-based sand and
gravel extraction. No active sand and gravel pits exist within the region and
no policies are currently in place for the safeguarding of potential resources.
From the standpoint of the individual MPA this could be justified, because:
(i)
quarrying creates some adverse
impacts on the surrounding population and environment, which are relatively well
understood; and
(ii)
the impacts associated with
marine dredging had been adjudged (by others) to be acceptable.
2.4
A peremptory policy shift away
from dredging and towards favouring land-based extraction would almost
inevitably cause disruption in the market for sand over the short term, while
applications to quarry sand and gravel went through the planning system. There
are alternative sources of sand-like materials (notably crushed rock sand), but
these are primarily suited to lower grade uses, and they are neither unlimited
nor free of adverse impacts of their own.
2.5
The Assembly has a general
objective of seeking sustainable solutions to policy dilemmas. It therefore
seeks to promote a sustainable balance of supply sources for aggregate. It has
to do this against a background of considerable uncertainty about what actually
happens on the sea bed both with and without the influence of dredging,
particularly as regards the long-term movement of sand and other sediments.
This means that it is not self evident that accepting the known adverse impacts
associated with land-based extraction in place of possible gains from stopping
dredging constitutes a good bargain.
2.6
After all, the changes which
are affecting the beaches and cliffs of South East Wales might simply be part
of a very slow long-term process, or they might be due to rising sea levels and
increased storm activity associated with global warming, or a combination of
all of these.
2.7
In view of its complexity, and
its importance, the issue of coastal change is introduced in Chapter 3 (and
dealt with in depth in Appendix 5). Chapter 3 also provides a short overview of
how this Study will deal with the complex question of sustainability.
2.8
Before that, a brief review of
the policy background is provided, along with other essential background to
understanding the methodology, which in turn is outlined in Chapter 4.
The Policy and Planning
Background
2.9
The policy and planning
background to this Study can be found in a range of documents of national,
regional, local and site-specific relevance. These are briefly identified
below.
2.10
At a national level, the
Assembly issued 'Mineral Planning Policy Wales' (MPPW) in December 2000. This
encourages each MPA in Wales to make provision for future land-based sand and gravel extraction
within the areas for which they are responsible. Even if resources are not
earmarked for development, MPPW encourages MPAs to safeguard known blocks of
resources, so that future decisions to exploit them are not ruled out by the
land having been 'sterilised' by built development.
2.11
In February 2002 the Assembly
took matters a step further by issuing a Consultation Draft Minerals Technical
Advice Note (Wales) covering aggregates (the Aggregates TAN). This document
sets out detailed advice to MPAs and the aggregates industry on the delivery of
the policies established in MPPW. When issued in its final form, the TAN will
supersede Minerals Planning Guidance Note 6, which previously applied to both Wales and
England.
2.12
At a regional level the
Assembly initiated a consultation process by issuing a document entitled
'Marine Aggregate Dredging Policy, South
Wales' in May 2001. The consultation
period ended in July 2001, and responses are currently being considered. MADP,
as the document is widely known, assigns one of four policy positions to all
areas of the Bristol Channel in which the Assembly has an interest. This has been done to
provide potential applicants for licences to dredge sand and gravel with prior
guidance on the approach which the Assembly is likely to take.
2.13
These four policy positions are
as follows:
(i)
Policy 1: the Assembly will
look favourably on dredging for marine aggregates in sediment environments
where few constraints have been identified (i.e. a positive Government View is
likely);
(ii)
Policy 2: the Assembly will
adopt a precautionary approach to policy until research and/or monitoring can
reduce uncertainty of the actual or potential effects of marine dredging to
acceptable levels (i.e. use dredging conditions to limit duration and tonnage
of licence, and review at end of 5-year interim strategy period);
(iii)
Policy 3: the Assembly will not
look favourably on dredging for marine aggregates in these sediment
environments due to the significance of constraints identified (i.e. a negative
Government View is likely);
(iv)
Policy 4: the Assembly will
safeguard marine aggregate resources in these sediment environments from
sterilisation by seabed development and other activities at sea for dredging in
the future.
2.14
There are 13 MPAs whose areas
of responsibility lie wholly within the study area (which is referred to
throughout this report as South East Wales). They are (in alphabetical order):
(i)
Blaenau Gwent County Borough Council;
(ii)
Brecon Beacons National Park;
(iii)
Bridgend County Borough Council;
(iv)
Cardiff County Council;
(v)
City & County of Swansea;
(vi)
Merthyr Tydfil County Borough Council;
(vii)
Monmouthshire County Council;
(viii)
Neath Port Talbot County Borough
Council;
(ix)
Newport County Borough Council;
(x)
Rhondda-Cynon-Taff County Borough Council;
(xi)
Torfaen County Borough Council;
(xii)
Vale of Glamorgan.
2.15
At the western end of the Brecon Beacons National Park
there is a small sliver of land which lies between the park's southern boundary
and the northern boundary of Neath Port Talbot County Borough Council. This
sliver of land includes small areas of Carmarthenshire and Powys, and is
included within the study area for reasons of 'geographical common sense'.
There are no quarries within this sliver of land. Figure 2.1 (at the end of
this Chapter) shows the study area.
2.16
At the local level, each MPA is
responsible for considering local aggregate supply issues. The conclusions of
this process should then be included within each Local Authority's Unitary
Development Plan (UDP). One of the main policy drivers which led to this study
being commissioned was the fact that none of the UDPs in South East Wales
includes any provision for the land-based quarrying of sand and gravel, despite
the growing pressure on marine dredging in the Bristol Channel. Some of this
pressure has come from Local Authorities.
2.17
There are various environmental
and planning designations which apply to areas of land and sea, and which
constitute material considerations in any application to extract or process
aggregate minerals. These designations include:
(i)
landscape and countryside
designations (such as National Parks, Areas of Outstanding Natural Beauty,
Green Belt / Green Wedge, Heritage Coast, Recreation Areas, Areas of Special
Landscape Value, and Common Land);
(ii)
ecological and nature
conservation designations (such as Special Protection Areas, Special Areas of
Conservation (both actual and candidate areas), Ramsar Sites, Sites of Special
Scientific Interest, National Nature Reserves, Marine Nature Reserves, Local
Nature Reserves, Ancient Woodland, and Regionally Important Geological /
Geomorphological Sites);
(iii)
historical designations (such
as Scheduled Ancient Monuments; Listed Buildings Grades 1&2, Conservation
Areas, Historical Parks Gardens and Landscapes, Archaeologically Sensitive
Areas, and Sites of Archaeological Interest);
(iv)
development planning and
transport designations (such as proposed housing development areas, proposed
commercial and employment areas, existing urban areas, and proposed transport
improvement development areas);
(v)
inland water-related
designations (such as areas liable to flooding, areas within the fluvial
floodplain, areas within the tidal floodplain, and areas above major
groundwater aquifers).
Previous Technical
Studies which led to this Report
2.18
Two technical reports in
particular provide essential background to this study and this report. Both
were commissioned by the Assembly, and both were completed in 2000. They are
generally referred to as:
(i)
'Bristol Channel Marine
Aggregates Study', by ABP Research & Consultancy and Posford Duvivier
Environment (referred to hereafter as ‘the BCMA Study’); and
(ii)
'South Wales Sand & Gravel:
Appraisal of Land-Based Extraction in South East Wales' by Symonds Group,
(referred to hereafter as 'the Symonds report ').
2.19
The BCMA Study sought to
establish the extent of resources of marine sand and (to a lesser extent)
gravel in the Bristol Channel, and the impacts which its dredging may be having or might have in
future. It divided the Bristol Channel into a series of 'sediment environments', of which 27 are wholly in
Welsh waters, and six cross the boundary between England
and Wales. These are the geographical units on which the proposals contained
in MADP (see above) were based.
2.20
The Symonds report:
(i)
identified a number of
potential, but as yet unproven, resource blocks in South East Wales from which sand
and gravel might be extracted in future;
(ii)
reported on the extent to which
these potential resource blocks coincided with environmental and planning
designations in place at that time; and
(iii)
considered the general
environmental and cost implications of exploiting alternative sources of sand
and gravel, including out-of-area resources.
2.21
Other technical reports which
are of significance include:
(i)
Technical Report WF/00/3/C by
the British Geological Survey (BGS), which sought to identify potentially
suitable outcrops of hard rock for quarrying and crushing;
(ii)
the Environmental Statement
dated March 2000 prepared by EMU Environmental which accompanied the current
application to continue dredging sand from Nash Bank;
(iii)
four reports on Nash Bank
prepared by HR Wallingford (Study of impacts on the coastline, 1996; Review of
survey data, 1999; Application for continued extraction, 1999; Review of survey
data, 2000);
(iv)
a report on Nash Bank by
Resource Management Associates (Bathymetric and volume assessment 1997-2000
data, 2001);
(v)
a report on Helwick Bank dated
August 1997 by HR Wallingford;
(vi)
a report by Coastal Geophysics
entitled 'Southeast Swansea Bay: Geophysical survey, spring 1995;
(vii)
the South Wales Regional Aggregates
Working Party Annual Report 2000;
(viii)
three reports by Collins et al from 1979, 1987 and 1995 reviewing
sediment transport in the Bristol Channel.
2.22
The Environmental Statement and
the Coastal Impact Study by HR Wallingford which will in due course accompany
the current application to extend dredging sand from Helwick Bank had not been
completed by the time this report was written, but will also constitute
important documents once they are in the public domain.
The Scope of this Study
2.23
The technical component of the
Research Specification issued by the Assembly is included as Appendix 1 to this
report. It sets out the aims of the project, the background, the objectives,
the general approach to be taken and the geographical scope of the study area.
2.24
The aims are:
(i)
"to assess the relative
environmental, amenity and economic impacts of utilising the various sand and
gravel source options available in South East Wales"; and
(ii)
"to provide robust data on
the overall sustainability of various options, to support decision making on
minerals policy".
2.25
The objectives are:
(i)
"to take forward the
issues identified in previous research into sand and gravel resources and
constraints, regarding the need to formulate a strategy for aggregates
provision in South East Wales";
(ii)
"to thoroughly evaluate
the relative environmental, amenity and socio-economic impacts of the various
options for sand and gravel supply in South East Wales"; and
(iii)
"to study such options in
the field and produce robust and meaningful conclusions which will allow some
forecasting and aid in policy development".
2.26
The section on the general
approach stresses the need for an approach "… that will involve a
structured sample of a carefully selected range of sites, using strict and
replicable data gathering and analytical protocols". It goes on to
emphasise the importance of identifying "… the relative impacts of
utilising potential resource options", and the fact that "… the
research design must be aimed at acquiring data that is capable of
demonstrating the comparative environmental and social costs or benefits of the
resource options available".
2.27
Appendix 1 also lists the
members of the Steering Group established by the Assembly to follow the
progress of this study, and to provide feed-back on its approach and findings.
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Coastal Change
3.1
One of the most powerful
driving forces for considering alternatives to marine-dredged aggregate is the
concern that has been expressed that dredging sand from the seabed might have
adverse impacts on the beaches and cliffs of South East Wales.
3.2
Historical topographic and
bathymetric data reveal that there has been significant change along the coast
of South East Wales: erosion of beaches and cliffs in some areas, and accretion in
others. This has been ongoing since long before dredging began, however, and,
despite considerable research effort, no specific trend in either the scale or
pattern of changes has hitherto been identified that can be attributed, with
any justification, to dredging activities.
3.3
Whilst this is true of the
coast, it may not be the case for some of the licensed dredging areas
themselves. At Nash Bank, for example, repeat bathymetric surveys have revealed
significant changes to the overall size and shape of the westernmost part of
the bank, as a direct result of dredging. These changes have been superimposed
on, and have disrupted, a natural pattern of substantial, systematic
morphological changes that has been taking place since long before dredging
began.
3.4
The present study has, for the
first time, investigated these changes in detail, from a geomorphological
perspective, in order to determine their possible implications for future
changes on the coastline.
3.5
The findings of the new
research on coastal changes carried out in connection with this study are summarised
in Appendix 5 and have fed into both the comparative sustainability assessment
in Chapter 8, and the overall conclusions and recommendations set out in
Chapter 9.
Sustainability
3.6
In recent years the issue of
sustainability has also risen up the political and policy agenda. The general
agreement on the importance of sustainability is often matched by a lack of
agreement on what it means at a practical level. This section seeks to explain
how sustainability is being dealt with in this study, starting with what it
means.
3.7
To complement the definition of
sustainability given in the 'Brundtland Report' (1987) (i.e. "meeting the
needs of the present without compromising the ability of future generations to
meet their own needs"), the following more recent definition of
sustainable development (attributed to 'Forum for the Future', a UK-based
sustainable development charity) is helpful.
"Sustainable development is a
process which enables all people to realize their potential and improve their
quality of life in ways that simultaneously protect and enhance the Earth's
life-support systems"
3.8
Sustainable development clearly
has a social and an economic component as well as an environmental one, and
governments are inclined to give greater weight to the economic and social
components than 'pure' environmentalists might. The British Government's vision
of sustainable development (see, for example, 'A Strategy for Sustainable
Development for the UK', May 1999) is based on balancing and achieving four broad
objectives, which are expressed as follows:
(i)
social progress which
recognises the needs of everyone;
(ii)
effective protection of the
environment;
(iii)
prudent use of natural
resources; and
(iv)
maintenance of high and stable
levels of economic growth and employment.
3.9
These objectives are described
in greater detail in the same publication, and in Ministerial speeches, as
follows:
(i)
social progress encompasses
sharing the benefits of prosperity, through a clean, safe environment, and
improved health and education;
(ii)
environmental protection
involves ensuring that people's health does not suffer from poor air quality or
other pollution, as well as protecting wildlife and the countryside;
(iii)
prudent resource use refers to
using resources efficiently and minimising waste;
(iv)
growth and employment are
necessary so that everyone can share in high living standards and greater job
opportunities, and to generate the income and wealth needed to pay for
essential infrastructure and future investments.
3.10
The Web page http://www.wales.gov.uk/themessustainabledev/recent-e.htm
tracks the Assembly's evolving policies and documents dealing with sustainable
development, including 'Learning to Live Differently', which sets out the
Assembly's general approach to sustainable development.
3.11
The related Web page at http://www.wales.gov.uk/themessustainabledev/index.htm
provides an overview which endorses the approach outlined above, and confirms
that "… the Assembly in its turn aims to add value to work done at the UK level
on sustainability, building on the UK
strategy, reflecting the needs of Wales as
necessary". It also confirms that "… the theme of sustainable
development, linked with that of social inclusion, runs through the Strategic
Plan 'Better Wales' that the Assembly published in March 2000". ‘Better Wales’
has since been replaced by ‘Plan for Wales’,
which can be accessed at www.planforwales.wales.gov.uk.
3.12
Sustainability is therefore all
about balancing the demands of economic development and the needs of both
individuals and society against the constraints created by natural systems and
against each other. Above all it involves finding an appropriate utilisation
rate for non-renewable resources, including energy, and avoiding actions which
compromise the functionality of natural 'sinks' (e.g. the ability of natural
systems to absorb and deal with pollution and waste of all kinds).
3.13
Whereas individual actions are
important, true sustainability can only be achieved and measured taking into
account the overall behaviour of a population and its impact on a region. It is
not enough to live in a so-called sustainable house if the neighbourhood
depends on unsustainable behaviour.
3.14
There are relatively simple
conceptual models that link together:
(i)
economic driving forces
(including industry, households, the energy sector, transport services,
agriculture and tourism); and
(ii)
the stocks of natural resources
on which they draw (including soil, minerals, water, air, flora and fauna); via
(iii)
the pressures that they create
(in the form of emissions and waste).
3.15
However, the science that
underpins such models is far from simple, and they cannot, as a general rule,
be used for quantitative prediction.
3.16
Excessive (i.e. unsustainable)
pressures lead to, and are eventually revealed by, severe impacts. Evidence of
unsustainable pressures might include:
(i)
climate change;
(ii)
the progressive destruction of
ecosystems (whether natural, modified or artificial), possibly leading to the
extinction of certain species, or an inability to produce an essential benefit
(such as food);
(iii)
the using up of a scarce
mineral resource;
(iv)
the fouling of drinking water
supplies; or
(v)
the destabilisation of natural
systems (leading to, for example, increased flooding, even before taking into
account the effects of climate change).
3.17
Comparable linkages exist
between economic activity and social systems. Social systems can be thought of
as 'human ecology', while the accumulated capital from earlier human activity
is contained in (among other things) productive resources (such as factories
and mines), archaeological remains, architectural heritage and the managed
landscape which characterises much of the developed world (and an increasing
share of the developing world).
3.18
An important test, which can be
applied to any proposal or development, involves establishing whether it is
likely to move the world closer to, or further from, the ideal of true
sustainability. The specific mechanism by which this is achieved in the context
of this study is described more fully in Chapter 7 and Appendix 4.
3.19
Briefly, the model which is
used to view and assess the balance between the competing demands of the natural
environment, the community and the need for economic development is based on
the concept that the resources available to society can be treated as 'stocks
of capital', from which a range of benefits can flow. These benefits include
all of the things that are needed in order to maintain life and civilisation.
3.20
The stocks of resources can be
broken down into environmental, social (mainly human) and economic capital.
Figure 3.1 is a simplification (in that it combines the concepts of social and
economic capital under a single heading).
|
Figure 3.1
|
12 items of environmental and social/economic
capital involved in sustainability, and their relevance to aggregate
production and use
|
|
No.
|
Six items of environmental capital
|
Notes/explanation
|
|
1
|
Fossil
fuels.
|
Includes
production and processing energy, plus transport/traffic from product
delivery and workforce travel-to-work.
|
|
2
|
Soil
resources and non-energy minerals.
|
Includes
competition for land.
|
|
3
|
Fresh
water resources.
|
Includes
considerations of surface and groundwater.
|
|
4
|
The
sea.
|
Includes
water quality, currents and coastal processes.
|
|
5
|
The
air and the climate.
|
Includes
quarry and transport emissions of carbon dioxide, pollutants and dust.
|
|
6
|
Ecosystems.
|
Includes
considerations of terrestrial and marine habitats, biodiversity and protected
areas/species.
|
|
No.
|
Six items of social/economic capital
|
Notes/explanation
|
|
1
|
Human
health.
|
Includes
stress and health effects from noise, vibration, dust, general air quality,
and from quality of life associated with surrounds (including landscape and
visual quality). Potential future impacts would include those from landfills
using void spaces.
|
|
2
|
Knowledge
and learning.
|
Might
include impacts associated with the quality of jobs and training, and
potential impacts on archaeology and heritage.
|
|
3
|
Social
inclusion.
|
Includes
issues arising from employment (quantity and quality). Issues such as
governance are not likely to arise.
|
|
4
|
Housing.
|
Includes
availability and suitability of building materials, possible damage to
housing, competition for space and possible flood impacts. Wider
considerations include the relationship between housing and landscape, and
countryside access.
|
|
5
|
The
means of production
|
Might
include impacts on factories, including availability of building materials.
|
|
6
|
Transport
and energy infrastructure
|
Includes
knock-on impacts from materials transport, plus contributions to
infrastructure from relevant materials.
|
|
|
|
|
3.21
These are the 12 headings under
which judgements on sustainability are taken in this study. The notes and
explanations in Figure 3.1 are tailored to the specifics of this study and the
issues raised by aggregate extraction and use.
Introductory Comments
4.1
The choices involved in
diversifying from the present heavy reliance on marine-dredged sand are not
simple. Generally speaking land-based resources of sand occur in combination
with gravel, though once sand and gravel have been dug, they are used either
separately or in varying combinations, depending on the application. Within
South East Wales, a large proportion of the marine-dredged (and gravel-free)
sand is currently blended with crushed rock to achieve a suitable aggregate for
making concrete.
4.2
Therefore replacing
marine-dredged sand with quarried sand has knock-on implications for the gravel
and crushed rock markets. In South East Wales, as in all other regions, the
share of gravel and crushed rock in the aggregate market is significantly
greater than the tonnage of sand.
4.3
It is also important to bear in
mind that 'sand' is a varied material, and that different types of sand have
different uses and limitations. Typically, marine sand is particularly 'soft',
due to the rounded nature of its grains, whereas land-based sand is often more
angular or 'sharp'. Sand produced by crushing rock from a quarry is
considerably sharper still. These differences have practical implications,
because the physical shape of grains, in combination with their size
distribution, determines how easily worked the sand is when damp, and how much
water, cement and other additives need to be used when mixing mortar or
concrete.
4.4
This study seeks, above all, to
compare alternatives to the present supply pattern. Although changes may be
driven by changing the source(s) of sand, the knock-on impacts on gravel and
crushed rock sources must also be considered. In other words, the comparison
must be between balanced patterns of supply, and not between individual
elements of the portfolio.
4.5
The methodology adopted in this
study is first to characterise the current balance of sand and coarse aggregate
supply to the South East Wales market, and then to consider the sustainability
implications of reducing the supply of marine-dredged sand (by, for example,
ceasing to dredge from one or more of the main areas that are currently
licensed).
Identifying Alternative
Patterns of Supply
4.6
The first step in the
methodology is to describe the current supply pattern for sand and coarse
aggregate, in order to establish the baseline against which alternatives need
to be judged. This has been done by drawing on previous studies, other publicly
available information and data provided by (among others) the members of the
study Steering Group.
4.7
The outcome of this process is
reported in Chapter 5, where it is confirmed that the large majority of sand
used in South East Wales comes from three areas: Nash Bank (to the south of
Porthcawl), Helwick Bank (to the south of the Gower peninsula) and Holm Sands
(to the south of the Vale of Glamorgan). Most coarse aggregate comes from 17
limestone quarries spread throughout the region. There are currently no sand
and gravel quarries in South East Wales.
4.8
The next step is to examine not
just how changes in the current pattern of supply might be brought about, but
also what these changes might be. This is done in Chapter 6, which sets out
three alternative balanced patterns of supply responding to a range of possible
future restrictions on marine dredging. In all three cases the intention is to
predict, as far as is possible, the most likely market responses to the changed
policy scenarios, and in particular the patterns of supply which might emerge.
It must be stressed that these possible future patterns of supply are produced
in order that they can be assessed, and so that conclusions can be drawn from
that assessment. They are neither precise forecasts nor recommendations, simply
assessment tools.
4.9
The three alternative scenarios
are based on the following potential policy events, and accompanying
assumptions:
(i)
an end to the dredging of sand
from Nash Bank, without any sand and gravel quarries being opened in South East
Wales, and without any additional dredging licences being issued for dredging
in the Bristol Channel;
(ii)
an end to the dredging of sand
from both Nash Bank and Helwick Bank, again without any new sand and gravel
quarries being opened in South East Wales, but with two additional dredging
licences being issued, permitting new dredging further offshore in the Bristol
Channel;
(iii)
an end to the dredging of sand
from both Nash Bank and Helwick Bank, but with sand and gravel and crushed rock
quarries being permitted at various locations in South East Wales if required,
and with two additional dredging licences being issued, permitting new dredging
further offshore in the Bristol Channel.
4.10
The current position is
referred to as either the baseline position or Pattern of Supply No. 1.
The responses to the three alternative policy scenarios are referred to as
Patterns of Supply Nos. 2, 3 and 4 respectively.
Selecting and Assessing
Representative Sources and Sites
4.11
To compare the four patterns of
supply at all convincingly, they need to be described in terms of their typical
component elements. This is because the four patterns of supply involve drawing
on changing combinations of materials from a range of different supply options
(dredging, quarrying, recycling etc).
4.12
While some supply options are
tied to a particular location, others may be carried out at a range of
specified locations. A combination of supply option and location is referred to
as a supply source. This relationships between a range of supply options and
four different (and entirely notional) patterns of supply are illustrated
schematically in Figure 4.1, while Figure 4.2 does the same thing for supply
sources. However, it must be stressed that these are simplifications to
illustrate a general point, not a summary of the actual patterns of supply to
be considered in this study.
|
Figure 4.1
|
Schematic
representation of the way in which individual supply options might be
combined to create patterns of supply
|
|
Supply
options
|
Notional
patterns of supply
|
|
1
|
2
|
3
|
4
|
|
Dredging
|
25%
|
25%
|
35%
|
30%
|
|
Quarrying
|
75%
|
65%
|
40%
|
45%
|
|
Recycling
|
-
|
10%
|
25%
|
25%
|
|
Total
|
100%
|
100%
|
100%
|
100%
|
|
Note:
|
These figures are purely illustrative, and are not intended to
represent either the current or the likely future position in South East
Wales.
|
|
|
|
|
|
|
|
|
Figure 4.2
|
Schematic
representation of the way in which individual supply sources might be
combined to create patterns of supply
|
|
Supply
sources
|
Notional
patterns of supply
|
|
1
|
2
|
3
|
4
|
|
Dredging at A
|
25%
|
10%
|
5%
|
-
|
|
Dredging at B
|
-
|
15%
|
30%
|
30%
|
|
Quarrying at C
|
65%
|
50%
|
15%
|
20%
|
|
Quarrying at D
|
10%
|
15%
|
25%
|
25%
|
|
Recycling at E
|
-
|
10%
|
25%
|
25%
|
|
Total
|
100%
|
100%
|
100%
|
100%
|
|
Note:
|
These figures are purely illustrative, and are not intended to
represent either the current or the likely future position in South East
Wales.
|
|
|
|
|
|
|
|
4.13
In constructing viable patterns
of supply, the first step is to ensure that all realistic supply options,
including those employed at present, are considered. The general
characteristics of these supply options then have to be set down on paper.
4.14
The principal supply options
considered in this study are listed in Figure 4.3, and individual fact sheets
detailing the characteristics of these material(s), their availability, the
way(s) in which they are produced and the main impacts associated with their
production, processing, transport and performance are given in Appendix 2.
Figure 4.3 also shows whether the supply options concerned provide sand, coarse
aggregate (gravel, crushed rock or fill material) or both.
4.15
Some other types of secondary
aggregate materials not listed in Figure 4.3 are also discussed in Chapters 5
and 6 (dealing with the current pattern of supply and future alternatives,
respectively). However, as is explained there, none of these secondary
materials offer direct alternatives to marine-dredged sand, which makes them of
limited relevance to this study.
|
Figure 4.3
|
12 Supply
Options considered in this study
|
|
|
Option
|
Description
|
Sand?
|
Coarse
aggregate?
|
|
1
|
|
Yes
|
No
|
|
2
|
Marine-dredged
sand from the Bristol Channel, but further offshore than Option 1
|
Yes
|
No
|
|
3
|
Limestone
aggregate from existing quarries in South East Wales
|
Yes
|
Yes
|
|
4
|
Land-won sand
and gravel from future quarries in South East Wales
|
Yes
|
Yes
|
|
5
|
Crushed rock
sand from existing Pennant Sandstone quarries in South East Wales
|
Yes
|
No(1)
|
|
6
|
Crushed rock
sand from future hard rock quarries in South East Wales
|
Yes
|
No(2)
|
|
7
|
|
Yes
|
No(3)
|
|
8
|
China Clay
sand from Cornwall and Devon
|
Yes
|
No
|
|
9
|
Land-won sand and gravel from quarries in England,
delivered by rail and/or road
|
Yes
|
Yes(4)
|
|
10
|
Dredged
materials from port maintenance in South East Wales
|
Yes(5)
|
Yes(6)
|
|
11
|
Foundry sand
from the castings industry or old foundry landfills in South East Wales
|
Yes
|
No
|
|
12
|
Recycled
aggregate produced from demolition waste in South East Wales
|
No
|
Yes
|
|
Notes
|
(1)
|
While the fines could be
recovered as a substitute for sand, the coarse aggregate from Pennant
Sandstone quarries would continue to be used as at present (i.e. primarily
for road making, rather than for concrete).
|
|
|
(2)
|
The primary purpose of such
a quarry would be to produce a sand substitute. Rock types suitable for this
would probably be too weak for the production of useable coarse aggregate.
|
|
|
(3)
|
|
|
|
(4)
|
This material would
probably be brought into South East Wales as mixed sand and gravel.
|
|
|
(5)
|
Material dredged from parts
of the river Neath contains a high proportion of fine sand.
|
|
|
(6)
|
Although not coarse, some dredged material can displace aggregate as
general fill material in some applications.
|
|
|
|
|
|
|
|
|
4.16
The Research Specification for
this project confirms that the Assembly is looking for general guidance on the
relative sustainability of different patterns of supply which can guide policy
in the medium to long term. Although representative sites are to be considered,
the conclusions drawn from them should not be tied to specific scales of
activity and particular locations. In any event, while some of the supply options
can be seen in action already, others are purely theoretical.
4.17
What is needed, therefore, is a
set of broadly representative sites which are sufficiently specific to be
credible, without giving rise to unfounded concerns regarding impending
extraction or processing. Hence the representative supply sources identified
and described in Chapter 7 are in some cases described along the lines of 'a
recycling site on the outskirts of Cardiff' rather than 'a recycling site on
XYZ Road, Cardiff'.
4.18
There is an inevitable
trade-off between the number of sites that can be assessed and the cost and
complexity of the study. Some supply options can be represented by a single
general location, while others demand more examples at different (actual or
potential) locations.
4.19
The selection of representative
sites also has to take into account the degree of uncertainty associated with
some impacts, and particularly those associated with marine dredging. Indeed
dealing with uncertainty is one of the key aspects of the whole study, since
the level of agreement even among experts on some topics is notably low.
Comparing the Relative
Sustainability of Alternative Patterns of Supply
4.20
In Chapter 6, four patterns of
supply are established (i.e. the current baseline position and three alternatives).
In Chapter 7 these are linked to varying combinations of the individual
site-specific case studies, as illustrated schematically in Figure 4.2. This
enables the environmental and social/economic impacts of changing the pattern
of aggregate supply to be assessed, because each pattern of supply will be made
up of a group of individual case studies 'weighted' according to their relative
contribution.
4.21
To compare relative
sustainability, what matters is the difference between the current baseline and
each alternative individual pattern of supply. Comparisons are therefore made
(in Chapter 8) of three pairings:
(i)
Pattern of Supply No. 2
compared to Pattern of Supply No. 1;
(ii)
Pattern of Supply No. 3
compared to Pattern of Supply No. 1; and
(iii)
Pattern of Supply No. 4
compared to Pattern of Supply No. 1.
4.22
The broad issues involved in
sustainability were set out in Chapter 3. A fuller discussion of the issues is
included as Appendix 4 to this report, which also provides an overview of the
specific process by which sustainability is assessed in practice.
4.23
Evaluating the impacts is
achieved by asking a series of technical questions about the scenarios which
are being compared. All of these questions are given in full in Appendix 4, and
the results are reported in Chapter 8 and Appendices 7-9. As can be seen in
Appendix 4, the questions seek to take a balanced approach to environmental
concerns and to the social and economic consequences of a change to the present
arrangements.
4.24
This highlights the difference
between 'pure' environmental assessment and sustainability assessment, which is
also concerned with issues such as the levels and quality of employment, and
the state of a region's physical and social infrastructure.
Sand Dredged from the
Bristol Channel
5.1
There are four main dredging
areas in Welsh waters in the Bristol Channel. Going from west to east, these
are Helwick Bank, Nash Bank, Holm Sands and Bedwin Sands. Dredging at the first
three of these sites (and some others) is licensed by the Crown Estate. Their
website (see www.crownestate.co.uk/estates/
marine/area_maps2000/) shows 11 dredging licences in the Bristol Channel.
These are listed in Figure 5.1, with the relevant block references and policies
from MADP also given. One of these licences, which has now lapsed, was a
relatively small one-off arrangement for the construction of the Cardiff Bay
barrage. Another (Denny Shoal) primarily supplies Avonmouth on the English side
of the Bristol Channel.
5.2
These dredging areas are also
mapped on Figure 5.7 (which will be found at the end of this chapter), together
with other land-based resource information.
|
Figure 5.1
|
Crown Estate dredging
licences in the Bristol Channel, 2000
|
|
Area name
|
MADP block
|
MADP policy(1)
|
Crown Estate licence
|
Licensee
|
|
Helwick Bank
|
OBC11
|
2
|
373
|
Llanelli Sand Dredging Ltd(2)
|
|
Nash Bank
|
CBC1
|
2
|
376
|
Hanson Aggregates Marine Ltd
|
|
378
|
South Coast Shipping Ltd(3)
|
|
380
|
United Marine Dredging Ltd(4)
|
|
Holm Sands
|
IBC3
|
2
|
377
|
Hanson Aggregates Marine Ltd
|
|
379
|
South Coast Shipping Ltd(3)
|
|
381
|
United Marine Dredging Ltd(4)
|
|
Culver Sands
|
IBC2
|
1
|
389
|
Hanson Aggregates Marine Ltd
|
|
Middle Ground
|
SE4
|
2
|
385
|
South Coast Shipping Ltd(3)
|
|
Denny Shoal
|
SE4
|
2
|
391
|
Hanson Aggregates Marine Ltd
|
|
Bristol Deep
|
SE4
|
2
|
425
(lapsed)
|
Cardiff Bay Development Corporation
|
|
Notes
|
(1)
|
MADP Policy 1 implies a favourable view on dredging; Policy 2 implies
a precautionary approach.
|
|
|
(2)
|
An associate company of Westminster Dredging Co Ltd, the UK operating
division of the Royal Boskalis Westminster Group. Not a member of BMAPA.
|
|
|
(3)
|
Part of the RMC Group.
|
|
|
(4)
|
A joint venture between Hanson and Tarmac.
|
|
|
|
|
|
|
|
|
5.3
Most of the companies
identified in Figure 5.1 are members of the British Marine Aggregate Producers
Association (BMAPA, see www.bmapa.org for
information). The assistance of BMAPA in helping to assemble and explain the
information in this section of the report is gratefully acknowledged.
5.4
Helwick Bank, which lies within
the Carmarthen Bay and Estuaries candidate Special Area of Conservation, is
close to the edge of the study area. The licensee (Llanelli Sand Dredging,
which is not a member of BMAPA) is based in Carmarthenshire, which is outside
the study area. All of their sand is landed at Burry Port, to the west of
Llanelli. This does not, of course, preclude sand from Helwick Bank from being
supplied to customers in South East Wales.
5.5
The current licence for Helwick
Bank, which expires in May 2003, is for up to 150,000 tonnes a year, which the
licensee is seeking to raise in steps to 300,000 tonnes a year, and to extend
at that rate (300,000 tonnes a year) for a further 15 years. Information
provided in the Assembly in answer to a written question (WAQ 4313, March
2000) confirms that the average annual 'take' from Helwick Bank over the period
1995-1999 inclusive was 87,816 tonnes. Based on a short discussion with
Llanelli Sand Dredging, it is estimated that around 30,000 tonnes a year of marine
sand enters the South East Wales market from Helwick Bank/Burry Port, for sale
in the Swansea area. Most of this (probably as much as 80%) is sold as
builder's sand, with the balance used in concrete.
5.6
In addition to the applications
outlined above, Llanelli Sand Dredging has submitted a separate application to
dredge up to 300,000 tonnes a year from Nobel (North Outer Bristol
Channel) Banks. Nobel Banks (which do not appear under this name on any
charts) lie south west of Helwick Bank, and 90% of the application area of
98 km2 lies within MADP sediment area OBC10, which is subject
to Policy 1 (explained in the footnotes to Figure 5.1). The remaining 10% is
split between areas OBC11 and 19, both subject to Policy 2. The centre point of
the application area lies 4-5 km south of the triple point between these
three areas.
5.7
The primary contributor of
marine-dredged sand in recent years, and particularly of builder's sand, has
been Nash Bank. The annual limit on extraction is currently set at 900,000
tonnes. The licence was due to expire on 4 February 2001, but temporary
extensions have been granted, first a 4-month extension to 4 June 2001, and
then an 8-month extension to 4 February 2002 and most recently a 12-month
extension to 4 February 2003. Information provided in the Assembly in answer to
a written question (WAQ 4313, March 2000) confirms that the average annual
'take' from Nash Bank over the period 1995-1999 inclusive was just under
700,000 tonnes, compared to a figure of just over 1.25 million tonnes for the
preceding 5-year period. The three companies which dredge Nash Bank (and Holm
Sands, plus other areas individually) are members of BMAPA.
5.8
The largest licence, at least
in terms of the upper tonnage limit, is the one which applies to Holm Sands.
However, although the maximum annual 'take' from Holm Sands was set at
2,975,000 tonnes, the tonnage actually dredged has been well below the limit in
recent years, at around 100,000-200,000 tonnes a year. This reflects relative
difficulties in obtaining high quality materials competitively.
5.9
Sand from Nash Bank is landed
at six ports and/or groups of river wharves in South East Wales (at Swansea,
Briton Ferry, Port Talbot, Barry, Cardiff and Newport) plus Pembroke, which
lies well to the west of the study area. Sand from Holm Sands is landed at five
of the same six ports/wharves in South East Wales (as listed above, but
excluding Port Talbot). There are concrete plants within the port areas at
Swansea, Cardiff and Newport, and adjacent to one of the sand wharves at each
of Briton Ferry and Newport.
5.10
Further south from Holm Sands
lies Culver Sands. The current Culver Sands licence is small (around 18,000
tonnes a year). Although the licensed area spans the boundary between Welsh and
English waters, the sand is all understood to be landed in South East Wales. A
further licence application to dredge 1.5 million tonnes a year from Culver
Sands was submitted in August 2000.
5.11
Middle Ground and Denny Shoal
serve the markets of South East Wales (Barry, Cardiff and Newport) and Avon
respectively. The upper licence limit for West Middle Ground is 250,000 tonnes
a year, though significantly less than this (estimated at 40,000-60,000 tonnes
a year) is dredged in a 'typical' year. There is also an application to dredge
up to 1 million tonnes per year from North Bristol Deep by United Marine
Dredging and Hanson Aggregates Marine.
5.12
A further operator (Severn
Sands, not a member of BMAPA) dredges sand from non-Crown Estate land on Bedwin
Sands. They hold a licence from Swangrove Estate and a planning permission from
the former Gwent County Council which are both valid until 2015. Their licence
is for up to 150,000 tonnes a year, of which roughly 40,000 tonnes of sand is
landed at Chepstow and 110,000 tonnes within the port area at Newport, where
Severn Sands operate a concrete plant. Severn Sands also submitted a further
licence application relating to North Middle Ground in July 2000. That
application is to dredge up to 400,000 tonnes a year for at least 10 years.
5.13
Figure 5.2 draws together the
tonnages landed by the different companies at each of the ports in South East
Wales.
5.14
Based primarily on information
from BMAPA members, the split between concrete sand, coarse builder's sand (and
similar), fine builder's sand (and similar) and low value uses (such as
engineering fill, for which sand, and particularly soft sand, is not
technically necessary) has been estimated, for the purposes of this study, to
be 48:24:24:4. BMAPA's figures, supplemented by estimates covering the other
two companies, show that the split between concrete sand and builder's sand was
almost exactly 50:50. It is Symonds' own assumption that the 50% comprising
builder's sand was divided 50:50 between coarse and fine sand, with a small
amount (4% of the total) used as fill.
|
Figure 5.2
|
Where sand dredged in the
Bristol Channel was landed in South East Wales in 2000 ('000
tonnes), and what it was used for (excluding fill)
|
|
Port - Company
|
'000 tonnes
|
Concrete sand
|
Building sand
|
|
Swansea - Llanelli Sand Dredging
|
30(2)
|
20%
|
80%
|
|
Swansea - BMAPA(1)
|
104
|
53%
|
47%
|
|
Briton Ferry - BMAPA(1)
|
203
|
53%
|
47%
|
|
Port Talbot- BMAPA(1)
|
6
|
10%
|
90%
|
|
Barry - BMAPA(1)
|
33
|
17%
|
83%
|
|
Cardiff - BMAPA(1)
|
301
|
41%
|
59%
|
|
Newport - BMAPA(1)
|
313
|
63%
|
37%
|
|
Newport - Severn Sand
|
110
|
63%(3)
|
37%(3)
|
|
Chepstow - Severn Sand
|
40
|
10%(3)
|
90%(3)
|
|
Total
|
1,140
|
50%(4)
|
50%(4)
|
|
Notes
|
(1)
|
Consolidated figures from Nash Bank, Holm Sands, Culver Sands and
Middle Ground. Excludes 34,000 tonnes landed at Pembroke.
|
|
|
(2)
|
Actually landed at Burry Port, but supplied
to the Swansea area.
|
|
|
(3)
|
Symonds' own estimates.
|
|
|
(4)
|
Calculated from the individual port tonnages.
|
|
|
|
|
|
|
|
5.15
The dredgers used in the Bristol Channel are of two
types: trail dredgers and static dredgers. Both types screen and drain the sand
before it enters the hold, and have the necessary equipment to discharge the
sand direct to a quayside without the need for shore-based equipment. Once
landed, the sand requires no further washing, cleaning or screening.
5.16
The three BMAPA members between
them have the equivalent of 3.5 dredgers working in the Bristol Channel most of the
time. Allowing for the two non-BMAPA members, for sand landed at Welsh ports
outside the study area, for sand landed at English ports, and for dredgers
which are moved to other parts of the UK for
temporary periods, the dredging capacity serving the study area is
approximately 4 full-time ships. Although the capacities of individual dredgers
do vary, a 'typical' ship has the capacity to land 1,200 tonnes of sand per
tide (i.e. 2,400 tonnes per day). Tidal factors mean that access to certain
river wharves (particularly at Briton Ferry and Newport) is
restricted for part of each month.
5.17
As can be seen from these
figures, there is spare dredging capacity available in South East Wales. Four
ships delivering sand at a rate of 2,400 tonnes per day could land the current
estimated annual total (see Figure 5.2) of 1,140,000 tonnes in four months.
Statistics from the Crown Estate (reported in the South Wales Regional
Aggregates Working Party Annual Report, 2000) show that the tonnage of sand
landed in South Wales from their licensed areas has fallen steadily from 1.64 million
tonnes in 1996 to 1.31 million tonnes in 1998 and 1.06 million tonnes in 2000.
These figures differ slightly from those reported above, but not by a significant
amount. In any event, the downward trend is clear.
Aggregate Quarried
within South East Wales
5.18
All of the aggregate quarried
within the study area of South East Wales comprises crushed rock, and
specifically:
(i)
sandstone, of which the most
important element is Pennant Sandstone, a premium quality coarse aggregate used
primarily in road surfacing;
(ii)
crushed Carboniferous
Limestone, a traditional source of coarse aggregate for use in concrete, road
construction (but not surfacing) and other applications.
5.19
There are five Pennant
Sandstone quarries in South East Wales. In the mid-late 1990s these had an
estimated combined output of around 1 million tonnes a year of saleable
aggregate, though by 2000 output across the whole of South Wales had dropped
appreciably (as reported in the South Wales Regional Aggregates Working Party
Annual Report for 2000). The quarries are listed below in the second column of
Figure 5.3.
|
Figure 5.3
|
Pennant
Sandstone and Carboniferous Limestone quarries in South East Wales
|
|
Mineral
Planning Authority
|
Pennant
Sandstone quarries
|
Limestone
quarries
|
|
Large
(>500,000 tonnes/yr)
|
Medium
(200-500,000 tonnes/yr)
|
Small
(<200,000 tonnes/yr)
|
|
|
Cwm Nant Lleici (Agg.
Industries), Gilfach (RMC)
|
|
|
|
|
Bridgend
|
|
Cornelly (1) (Camrian/ Tarmac)
|
Grove (Tarmac) (4)
|
Gaens (T S Rees)
|
|
Vale of
Glamorgan
|
|
Wenvoe (RMC) (2)
|
Lithalun (Hanson)
|
Ewenny (Minimix), Longlands (Mason Bros), Pantyffynnon (Seth Hill)
|
|
Cardiff
|
|
Taffs Well (1) (RMC)
|
Creigiau (Tarmac)
|
Ton Mawr (T S Rees)
|
|
Newport
|
|
|
|
|
|
Monmouthshire
|
|
(3)
|
Livox (Hanson)
|
|
|
Rhondda-Cynon-Taff
|
Craig-yr-Hesg (Hanson)
|
Forest Wood (Hanson)(2)
|
|
|
|
Merthyr
Tydfil
|
Gelligaer (Hanson)
|
|
Vaynor(5) (Hanson)
|
|
|
Caerphilly
|
Hafod (Lafarge)
|
Machen (Hanson)
|
|
|
|
Blaenau Gwent
|
|
|
|
Trefil (Gryphonn)
|
|
Brecon Beacons National Park
|
|
|
Ammanford, Penderyn, Vaynor(5) (all Hanson)
|
|
|
Notes
|
(1)
|
Cornelly and Taffs Well are
both major sources of non-aggregate limestone for industrial use.
|
|
|
(2)
|
Forest Wood is partly
within Vale of Glamorgan and partly within Rhondda-Cynon-Taff.
|
|
|
(3)
|
Ifton (Hanson) is reported
to be inactive, but is understood to be a candidate for re-opening.
|
|
|
(4)
|
Grove Quarry is currently inactive.
|
|
|
(5)
|
Vaynor is partly in Merthyr Tydfil and partly
within the Brecon Beacons National Park.
|
|
|
|
|
|
|
|
|
5.20
A significant proportion of
their output is exported beyond South East Wales, much of it to England
and some as far as Scotland. Because of the nature of Pennant Sandstone and the uses to which
it is put, it can be treated as a stand-alone product which is of relevance to
the present study only because the large volume of fines generated in sandstone
quarries (typically 35-45% of the total tonnage quarried) has some potential as
a substitute for sand in concrete or bulk fill. Before sandstone fines can be
used in concrete, however, they require some element of treatment to remove
clay minerals and coal dust. This is discussed in more depth in Chapter 6.
5.21
The earlier Symonds report on
land-based extraction reported that the non-cement limestone quarries in South East
Wales had a combined output of around 7.5 million tonnes of aggregate between
them. As with Pennant Sandstone, by 2000 output was reported to have fallen
across all of South Wales, and the share ascribed to the study area in 2000 has been
estimated at 5.5 million tonnes. Of this, around 600,000 tonnes is reported to
be used in industry rather than as an aggregate. Most of the limestone quarries
lie between the Pennant Sandstone quarries and the Bristol Channel.
5.22
All Pennant Sandstone and
non-cement limestone quarries identified in the South Wales Regional Aggregates
Working Party Annual Report for 2000 as being both active and within the study
area are listed in Figure 5.3. They are arranged there by Local Authority area,
working roughly from west to east along the coast, and then from south to north
across the region. The non-Pennant sandstone quarries (which are not listed
below) are Cefn Cribbwr in Bridgend, Fforch-y-Garan in Rhondda-Cynon-Taff, Bryn
(Gelliargwelt Uchaf) in Caerphilly, and Pant in the Brecon Beacons National Park.
5.23
It is estimated that, of the
4.9 million tonnes of aggregate limestone (i.e. 5.5 million tonnes minus
600,000 tonnes) slightly under 300,000 tonnes of dust/fines is blended with
marine-dredged sand and used in concrete as a 50:50 mix, with a further 1.6
million tonnes providing the coarse fraction of concrete. The remainder is used
for other purposes.
Aggregate Imported from
outside South East Wales
5.24
Some sand and gravel quarried
outside the study area (e.g. from quarries in Carmarthenshire, Herefordshire or
Gloucestershire) is used in South East Wales from time to time. The AM97
Collation of aggregate statistics stated that 114,000 tonnes were imported into
South Wales. Since the majority of this would have been used in South East
Wales, it has been assumed for the purposes of this study that an estimate of
100,000 tonnes a year should be included in the current baseline position. It
is also assumed that this material is split 33:67 sand:gravel.
5.25
A modest amount of crushed rock
sand from Glensanda is imported through Newport for use in
concrete block manufacture. It is used in combination with marine-dredged sand.
Secondary and Recycled
Materials
5.26
The earlier Symonds report on
land-won aggregates identified a number of secondary and recycled aggregates
currently used in the construction industry in South East Wales, as follows:
(i)
fly ash (PFA) and furnace
bottom ash from power stations;
(ii)
various slags from steel works;
(iii)
minestone from collieries; and
(iv)
recycled demolition waste.
5.27
The Research Brief also refers
to maintenance dredging from harbours.
5.28
The only coal-fired power
station operating in South East Wales is Aberthaw 'B', owned and operated by
Innogy (formerly National Power). The amount of coal burned at Aberthaw, and
therefore the amount of ash produced, varies from year to year. 'Typical'
tonnages would be 50,000 tonnes of fly ash and 10,000 tonnes of furnace bottom
ash.
5.29
Physically, fly ash is a much
finer material than sand, and because it does not have the right grain size
distribution it cannot be considered to be a substitute for sand either in
concrete or in mortar. However, the physical and chemical characteristics of
fly ash mean that it can be used as a cement substitute, which makes it more
valuable than most general aggregate. Fly ash which is unsuited to use as a
cement substitute (because, for example, it has too high a carbon content, or
because it has become damp and gone lumpy while being stockpiled), can be used
as a bulk fill material. During 2000 around 100,000 tonnes of fly ash from old
ash lagoons at the Carmarthen Bay power station (just outside the study area)
were used to create the Millennium Coastal Park at Llanelli. (Source: www.ukqaa.org.uk/casestudyllanelli).
5.30
Furnace bottom ash, or clinker,
is almost all used in the manufacture of light-weight concrete blocks. Even if
ground down to a smaller particle size it could only displace sand in the least
demanding, lowest value applications, and even this is uncertain.
5.31
Power station ashes, therefore,
can be used in some applications for which natural aggregates might otherwise
be required. However, although they are used alongside natural sand and gravel,
they are not direct substitutes for marine-dredged sand.
5.32
With the closure of parts of
Llanwern, the only major remaining integrated steel works in South East Wales
is at Port Talbot. For the period prior to the closure of Llanwern, Symonds'
estimates for aggregate-type materials are: around 900,000 tonnes a year of air
cooled blast furnace slag, around 750,000 tonnes a year of ground granulated
blast furnace slag, around 1.15 million tonnes a year of basic oxygen furnace
slag and 60,000 tonnes a year of electric arc furnace slag. A significant
proportion of these materials were supplied to clients in England.
5.33
Ground granulated blast furnace
slag is a very fine-grained, high quality, high value replacement for cement.
As such it is further removed from natural sand than is power station fly ash.
Air cooled blast furnace slag, basic oxygen furnace slag and electric arc
furnace slag are quite different, with a much larger granule size. They are all
mainly used as high performance roadstone materials, and none of them,
therefore, has the potential to replace marine-dredged sand.
5.34
According to Chapter 9 of 'The
reclaimed and recycled construction materials handbook' (CIRIA publication
C513, 1999) "colliery spoil is the waste material produced in the process
of extracting deep-mined coal and preparing it for sale. These solid wastes are
disposed of on spoil heaps and are known as 'minestone' ". Although
minestone can in theory be recovered from old spoil heaps, this can seldom be
justified on either cost or environmental grounds.
5.35
Minestone is, by its very
nature, a variable material with poor durability characteristics. The CIRIA
report cited above acknowledges that a few unburnt spoils can be used to
produce poor quality concrete, but points to road construction, landscaping,
land reclamation and general fill as the most appropriate uses. Recently,
significant volumes of minestone diverted direct from the mine (i.e. not tipped
onto spoil heaps first) has been used in flood defence work in northern
England.
5.36
In summary, minestone has
extremely limited potential for use as a graded material, and certainly could
not be used to replace marine-dredged sand. The last remaining deep mine in
South East Wales is Tower Colliery, in Rhondda-Cynon-Taff, so the tonnage of
available material is in any case low and declining.
5.37
The best available estimate for
recycled aggregate (i.e. aggregate made from construction and demolition waste)
is contained in another report by Symonds, for the Environment Agency and the
DETR in association with the Assembly (published by the EA in 2001 as Technical
Report P402 'Construction and Demolition Waste'). That report gave an estimate
for all of Wales of just under 1.3 million tonnes of ‘hard’ construction and
demolition waste, of which just under 150,000 tonnes was landfilled and just
over 600,000 tonnes was used as aggregate in the open market. The balance was
used in landfill engineering or restoration, or on registered exempt sites.
These figures exclude materials which were wholly or mainly soil.
5.38
The most appropriate uses for
recycled aggregates are similar to those for minestone, though the quality of
the material is generally higher and more reliable. Most recycled aggregates
are used as unbound materials in road and carpark construction and general
engineering fill. The main 'problem' component of crushed and screened
construction and demolition waste is the crusher fines, which can contain
contaminants. They are sometimes used (in combination with compost and other
materials) to make soil-type materials, but could (and should) not be used as a
substitute for marine-dredged sand.
5.39
Based on the share of Wales'
population in the South East region, 60% of the estimates given above for
recycled aggregates have been included in the current baseline position.
5.40
'The reclaimed and recycled
construction materials handbook' (CIRIA publication C513, 1999) also discusses
the potential for using materials dredged from ports, estuaries and rivers
(referred to here as 'maintenance dredging'). It deals with their use in
landscaping, beach nourishment and river enhancement (see Chapter 12), and the
use of silt in brick manufacture (see Chapter 7). It draws attention to the
fact that sediment from ports may well be contaminated.
5.41
It lists all disposal licences
applicable to maintenance dredging materials which were both active in 1998 and
in excess of 500,000 tonnes. Of these around 9 million tonnes were in South
East Wales, including one licence in Port Talbot (for 3.1 million tonnes), two
licences in Cardiff (for 1.86 million tonnes and 999,999 tonnes), two licences
in Swansea (for 1.3 million tonnes and 637,500 tonnes), and one licence in
Newport (for 999,999 tonnes). The smaller of the two Cardiff licences was held
by the Cardiff Bay Development Corporation; all others were held by Associated
British Ports (ABP). ABP's website (see www.abports.co.uk)
contains a section dedicated to dredging, and mainly to maintenance dredging.
This confirms that most of the disposal that is carried out is at sea, or
within the estuaries concerned. In other words, most of the 9 million tonnes is
not landed.
5.42
There is, however, one location
where much of the above does not apply. Dredged material from the mouth of the
river Neath comprises predominantly sand, though this sand is finer than most
commercially dredged sand, and apparently of limited commercial value as a
consequence. The river Neath has for some years been dredged by/for BP, to
facilitate access to their berth near the sand wharves. However, in March 2002
BP was due to vacate that berth, placing the onus for future dredging on the
Neath Harbour Commissioners.
5.43
In 2000-2001 10,000 tonnes of
fine sand from the river Neath was deposited on Sker beach in a trial involving
BP, Shoreline Management Partnerships and Swansea Bay Coastal Engineering
Group.
5.44
ABP's website also confirms
that before a dredging disposal licence is issued, ABP must satisfy DEFRA (the
licensing authority concerned) "… that it has taken reasonable steps to
find alternative beneficial uses of dredged material. As most material from port
areas is fine silt, such opportunities are rare unless it is suitable for an
approved reclamation project. Where sand or gravel occur (more often associated
with capital dredging) uses such as beach recharge or for sea defences may be
possible. Increasingly, however, scientific study is showing that a possible
beneficial use is to return dredged material to the estuary system at a
convenient location in order to maintain the dynamics of the system and
therefore conserve the morphological and ecological development".
5.45
The general presumption,
therefore, is that these materials are generally of low (or no) value as a
source of clean aggregate. For the purposes of this study, it is assumed that a
nominal 50,000 tonnes a year of dredged material is used for functions (such as
bulk fill) for which aggregate or soil would otherwise have to be dug or
dredged, with the remainder replaced elsewhere at sea or in the estuaries from
which it was dredged. Most maintenance dredging materials are not suitable as a
substitute for marine sand, because they are completely different in terms of
grain size and strength.
Demand for Aggregate in
South East Wales
5.46
Figure 5.4 provides estimates
for the distances travelled by marine sand, from the different ports at which
it is landed to its point of first use. Because significant amounts of sand are
used in concrete, and because several of the concrete plants are located at the
ports where the sand is landed, this approach has an in-built tendency to
understate the distance travelled to the point of final use. A significant part
of this information was provided by the members of BMAPA, modified slightly to
take account of the sand landed by the other operators, and then rounded.
5.47
The figures for Port Talbot and
Chepstow are subject to greater uncertainty than the others, though they affect
relatively small tonnages. Four of the ports (Swansea, Port Talbot, Barry and
Chepstow) share a common transport pattern: 85% being supplied to users within
10 km of the port, 10% to users within 10-20 km, 4% to users within
20-30 km and 1% to users located further than 30 km away.
5.48
The figures for the three
largest ports (Briton Ferry, Cardiff and Newport) are more reliable. The river
wharves at Briton Ferry and Newport in particular tend to serve the more inland
markets.
5.49
Merthyr Tydfil lies more than
30 km from each of Briton Ferry, Cardiff and Newport, and Abergavenny is
approximately 30 km from Newport. Likewise, all of the towns along or
close to the A465 between Merthyr Tydfil and Abegavenny (e.g. Tredegar, Ebbw
Vale and Brynmawr) lie slightly over 30 km from Newport, as does Monmouth.
All of the towns north of these, and almost all of the Brecon Beacons National
Park, lie more than 30 km from any port.
|
Figure 5.4
|
Distance travelled by
sand from port to point of first use ('000 tonnes and %)
|
|
Port
|
'000 tonnes landed
|
< 10 km
|
10-20 km
|
20-30 km
|
> 30 km
|
|
Swansea
|
134
|
113.9
(85%)
|
13.4
(10%)
|
5.4
(4%)
|
1.3
(1%)
|
|
Briton Ferry
|
203
|
132.0
(65%)
|
20.3
(10%)
|
20.3
(10%)
|
30.5
(15%)
|
|
Port Talbot
|
6
|
5.1
(85%)
|
0.6
(10%)
|
0.2
(4%)
|
0.1
(1%)
|
|
Barry
|
33
|
28.1
(85%)
|
3.3
(10%)
|
1.3
(4%)
|
0.3
(1%)
|
|
Cardiff
|
301
|
225.8
(75%)
|
45.2
(15%)
|
24.1
(8%)
|
6.0
(2%)
|
|
Newport
|
423
|
275.0
(65%)
|
63.5
(15%)
|
33.8
(8%)
|
50.8
(12%)
|
|
Chepstow
|
40
|
34.0
(85%)
|
4.0
(10%)
|
1.6
(4%)
|
0.4
(1%)
|
|
Total
|
1,140
|
813.7
(71%)
|
150.2
(13%)
|
86.7
(8%)
|
89.4
(8%)
|
|
|
|
|
|
|
|
5.50
Of the major towns closer to
the coast, Bridgend lies furthest from any port, being over 20 km from
Briton Ferry and Barry, and over 30 km from Cardiff.
5.51
When the tonnages are totalled
and expressed as a percentage of all landings in South East Wales (see the
bottom line of Figure 5.4), it can be seen that 71% of all sand travels less
than 10 km from the port where it is landed to its point of use, with 13%
travelling 10-20 km, 8% travelling 20-30 km, and 8% travelling more
than 30 km.
5.52
As was noted above, this does
not account for any transport then required to take ready mixed concrete or
concrete blocks from the batching plant (and/or block making plant) to the
point of final use.
Summary of the Current
Pattern of Supply and Demand
5.53
Figures 5.5 and 5.6 pull
together data from the preceding sections (and estimates based on them, and
discussions at meetings of the Steering Group) to provide a summary of the
current pattern of supply and demand for aggregate within South East Wales,
omitting those materials which are not used as sand, aggregate or bulk fill, or
as a substitute for them.
5.54
Figure 5.7 maps the various
marine and land-based resource blocks and related facilities, together with
major centres of aggregate demand.
5.55
The assumptions and
approximations 'embedded' in Figures 5.5 and 5.6 are as follows:
(i)
none of the marine sand landed
in South East Wales is currently exported;
(ii)
of the marine sand used in
South East Wales 48% is used in concrete, 24% is used as coarse sand and 24% is
used as fine sand, with the remaining 4% used in low value applications (such
as fill) simply because it is the most appropriate material available at the
relevant place and time;
(iii)
all imported sand and gravel is
used in concrete, and is split 33:67 sand:gravel without requiring additional
sand or gravel to be blended into the mix;
(iv)
half of the marine sand
destined for concrete is blended with crushed limestone dust/fines to achieve a
roughly 50:50 mixture;
(v)
every tonne of sand and
limestone dust/fines used in concrete is matched by two tonnes of
gravel/crushed rock;
(vi)
most of the remaining crushed
limestone is used as graded aggregate, with the balance used as bulk fill;
(vii)
three quarters of the Pennant
Sandstone prepared as coated (or coatable) roadstone which is quarried in South
East Wales is then exported to England or Scotland;
(viii)
for every tonne of Pennant
Sandstone roadstone produced, 540 kg of fines are generated (i.e. 35% of
the total volume quarried is fines, an estimate which is at the lower end of
the generally accepted range), and most of this is used in 'blacktop' (some of
it in England), in quarry restoration, or as fill material;
(ix)
50% of power station fly ash is
used as bulk fill (the balance being used as a higher value cement substitute);
(x)
55% of blast furnace steel slag
is air cooled, most of which is then exported;
(xi)
50% of minestone is currently
'wasted' with the balance used as bulk fill;
(xii)
60% of Welsh construction and
demolition waste occurs in South East Wales, and (in the absence of any
evidence to the contrary) is processed and used in the same ways as in the rest
of Wales;
(xiii)
50,000 tonnes of maintenance
dredging waste is used as bulk fill on shore, with the balance disposed of
offshore, even if some of this is used for beach recharge or similar.
|
Figure 5.5
|
Sources of
aggregate in South East Wales (tonnes)
|
|
Material
|
Amount
produced or landed in SE Wales
|
Imports
(exports)
|
Wasted
(or otherwise used)
|
Used
as sand, coarse aggregate or fill in SE Wales
|
|
Marine-dredged
sand
|
1,140,000(1)
|
0
|
0
|
1,140,000
|
|
Crushed
limestone
|
5,500,000
|
0
|
(600,000)
|
4,900,000
|
|
Pennant
Sandstone roadstone
|
800,000
|
(600,000)
|
0
|
200,000
|
|
Pennant
Sandstone fines
|
432,000
|
(30,000)
|
(86,400)
|
315,600
|
|
Crushed rock
sand from Glensanda
|
0
|
40,000
|
0
|
40,000
|
|
Imported sand
and gravel
|
0
|
100,000
|
0
|
100,000
|
|
Power station
fly ash
|
50,000
|
0
|
(25,000)
|
25,000
|
|
Air cooled
blast furnace slag
|
907,500
|
(800,000)
|
0
|
107,500
|
|
Minestone
|
10,000
|
0
|
5,000
|
5,000
|
|
Recycled
C&D waste
|
769,800
|
0
|
88,800 plus (364,200)
|
316,800
|
|
Maintenance
dredging materials
|
50,000
|
0
|
0
|
50,000
|
|
Note
|
(1)
|
All but 18,000 tonnes from close to shore.
|
|
|
|
|
|
|
|
|
|
Figure 5.6
|
Uses of
aggregate in South East Wales (tonnes)
|
|
Material
|
Used
as sand, coarse aggregate or fill (see Fig 5.5)
|
Used
in concrete
|
Sand (other than in concrete, incl. in
blocks)
|
Graded
aggregate
|
Ungraded
aggregate or fill
|
|
Marine-dredged
sand
|
1,140,000
|
547,200
|
273,600 (coarse) plus 273,600 (fine)
|
0
|
45,600
|
|
Limestone dust
|
373,600
|
273,600
|
60,000 (coarse) plus 40,000 (fine)
|
|
|
|
Other crushed
limestone
|
4,526,400
|
1,647,912
|
|
2,158,866
|
719,622
|
|
Pennant Sandstone
roadstone
|
200,000
|
0
|
0
|
200,000
|
0
|
|
Pennant
Sandstone fines
|
315,600
|
3,156
|
28,404 (coarse)
|
0
|
284,040
|
|
Crushed rock
sand from Glensanda
|
40,000
|
0
|
40,000 (fine)
|
0
|
0
|
|
Imported sand
and gravel
|
100,000
|
100,000 (mixed sand and gravel)
|
0
|
0
|
0
|
|
Power station
fly ash
|
25,000
|
0
|
0
|
0
|
25,000
|
|
Air cooled
blast furnace slag
|
107,500
|
0
|
0
|
107,500
|
0
|
|
Minestone
|
5,000
|
0
|
0
|
0
|
5,000
|
|
Recycled
C&D waste
|
316,800
|
0
|
0
|
79,200
|
237,600
|
|
Maintenance
dredging materials
|
50,000
|
0
|
0
|
0
|
50,000
|
|
Total
|
7,199,900
|
2,571,868
|
715,604
|
2,545,566
|
1,366,862
|
|
|
|
|
|
|
|
(Figure 5.7 to be inserted here)
(This page is intentionally blank)
Alternative Sources of
Aggregate not Currently Exploited
Introductory comments
6.1
The earlier Symonds report on
land-based extraction identified a number of potential sources of sand and
gravel (or direct substitutes) which might be exploited at some future point.
These were summarised (in Figure 4.3 of this report), together with the current
sources of supply.
6.2
Figure 6.1 lists eight of those
sources. They are either not currently exploited, or are only marginally
exploited at present while having significant potential for expansion. The
other four sources have been omitted from this chapter on the grounds that they
have been discussed already in Chapter 5.
|
Figure 6.1
|
Eight
currently unused or under-used Supply Options considered in this study
|
|
Option
|
Description
|
Sand?
|
Coarse
aggregate?
|
|
2
|
Marine-dredged
sand from the Bristol Channel, but further offshore than Option 1
|
Yes
|
No
|
|
4
|
Land-won sand
and gravel from future quarries in South East Wales
|
Yes
|
Yes
|
|
5
|
Crushed rock
sand from existing Pennant Sandstone quarries in South East Wales
|
Yes
|
No(1)
|
|
6
|
Crushed rock
sand from future hard rock quarries in South East Wales
|
Yes
|
No(2)
|
|
7
|
Crushed rock
sand from the Glensanda coastal superquarry in Scotland
|
Yes
|
No(3)
|
|
8
|
China Clay
sand from Cornwall and Devon
|
Yes
|
No(4)
|
|
9
|
Land-won sand and gravel from quarries in England,
delivered by rail and/or road
|
Yes
|
Yes(5)
|
|
11
|
Foundry sand
from the castings industry or old foundry landfills in South East Wales
|
Yes
|
No
|
|
Notes
|
(1)
|
While the fines could be
recovered as a substitute for sand, the coarse aggregate from Pennant
Sandstone quarries would continue to be used as at present (i.e. primarily
for road making, rather than for concrete).
|
|
|
(2)
|
|
|
|
(3)
|
Glensanda is being
considered primarily as a source of secondary sand. It is also a source of
coarse aggregate for concrete, but would not be competitive with existing
limestone quarries in South East Wales.
|
|
|
(4)
|
Coarse aggregate from china
clay waste is also available, but is not being considered here.
|
|
|
(5)
|
This material would probably be brought into South East Wales as-dug,
i.e. mixed sand and gravel.
|
|
|
|
|
|
|
|
6.3
Summary Fact Sheets for each of
these can be found in Appendix 2. Nevertheless, some further comments are worth
making.
Marine dredging
6.4
Various sources of
marine-dredged sand are the subject of current applications, two of which
(Culver Sands and Nobel Banks) fall wholly or largely inside sediment
environments that are subject to MADP Policy 1 (i.e. the Assembly "… will
look favourably on dredging …").
6.5
As reported in Chapter 5, the
sediment environment known as Culver Sands (area IBC3) is already lightly
exploited. It spans the Welsh-English border, which runs down the centre line
of the Bristol Channel, and the part which is discussed here is the smaller
portion in Welsh waters, some 10 km offshore, beyond Nash Bank. The
application is for 1.5 million tonnes a year.
6.6
Nobel Banks is in a sediment
environment that is not currently exploited, further offshore from Helwick
Bank. It lies mainly (90%) within MADP area OBC10, with the balance split
equally between areas OBC11 and OBC19. Area OBC10 is a MADP Policy 1 area,
while the other two are Policy 2 areas. The application is for 300,000 tonnes a
year.
6.7
North Middle Ground is also the
subject of a new application to dredge, but it lies entirely within a MADP
Policy 2 area (SE4).
Quarrying
6.8
The availability of sand and
gravel resources within South East Wales was central to the earlier Symonds
report on land-based extraction. That report identified an estimated 111.6
million tonnes of minerals unaffected by known environmental and planning
constraints. The large majority of this (98.3 million tonnes, or 88%) is in
three areas, as follows:
(i)
an estimated 39.0 million
tonnes near Pontarddulais, to the north of Swansea;
(ii)
an estimated 34.0 million
tonnes near Pyle, spanning the boundary between Neath Port Talbot and Bridgend;
and
(iii)
an estimated 25.3 million
tonnes in the Pontyclun-Cowbridge area, spanning the boundary between
Rhondda-Cynon-Taff and Vale of Glamorgan.
6.9
These estimated tonnages are
divided into several blocks in each case, meaning that they would have to be
exploited (if that option were pursued) as several small-medium quarries.
6.10
Figure 6.2 is taken from the
earlier Symonds report (where it was Table 5.1) to show the estimated amounts
in all areas, and the proportions constrained and unconstrained by existing
environmental and planning constraints. The only changes made from the source
table involve re-ordering the blocks to run west to east and south to north (as
with the quarries discussed in Chapter 5), and to omit those areas where no
potential resources were identified. These resource blocks are also plotted on
Figure 6.3.
6.11
Whereas it may well be
reasonable to look first at unconstrained areas when seeking the most suitable
sites for future quarries, it must be borne in mind that some of the
environmental and planning constraints could well be overcome. For example,
much of the Usk Valley falls within the Brecon Beacons National Park. That does
not in itself preclude the development of quarries, but it does place an
obligation on the proponent of any future quarry to explain how quarrying would
be compatible with its surrounds. The Upper and Middle Usk Valley is also a
considerable distance from the main markets for aggregate, which lie relatively
close to the coast, between Swansea and Newport.
6.12
While
this present study was in progress, Symonds was informed that one of the larger
prospects in the Usk Valley (for which only limited borehole data had been
available in 1999) has been further investigated by a quarry operator. Auger
holes were drilled, samples were taken, and the samples were subject to
grading, physical and chemical analysis. A geophysical survey was also
undertaken. The gravel fraction was found to be from a mixture of rock types,
and the sand fraction was found to be generally somewhat fine. The recoverable
reserve was estimated to be only around one third of that indicated in the
earlier Symonds report, and the quality was felt unlikely to be competitive
with those materials which are currently available in the market, particularly
for the manufacture of concrete.
6.13
Whilst
the results of this evaluation should not be regarded as representative of the
Usk Valley as a whole, they do serve to emphasise the uncertainty surrounding
the estimates contained in Figure 6.2.
|
Figure 6.2
|
Summary of
constraints on potential sand and gravel resources identified in Symonds'
previous report to the Assembly
|
|
Area
|
Total
quantity unaffected by known environmental or planning constraints
|
Total
quantity affected by known environmental or planning constraints
|
Total
estimated quantity within potential resource blocks
|
|
Pontarddulais
|
39.0 million tonnes
|
31.3 million tonnes
|
70.3 million tonnes
|
|
Vale of Neath
|
3.3 million tonnes
|
0.0 million tonnes
|
3.3 million tonnes
|
|
Pyle
|
34.0 million tonnes
|
1.9 million tonnes
|
35.9 million tonnes
|
|
Bridgend
|
3.7 million tonnes
|
8.0 million tonnes
|
11.7 million tonnes
|
|
Cowbridge-Pontyclun
|
25.3 million tonnes
|
29.6 million tonnes
|
54.9 million tonnes
|
|
Upper Rhymney
Valley
|
2.6 million tonnes
|
1.4 million tonnes
|
4.0 million tonnes
|
|
Lower Rhymney
Valley
|
1.3 million tonnes
|
12.3 million tonnes
|
13.6 million tonnes
|
|
Lower Usk
Valley
|
0.5 million tonnes
|
40.8 million tonnes
|
41.3 million tonnes
|
|
Middle Usk
Valley
|
1.9 million tonnes
|
132.8 million tonnes
|
134.7 million tonnes
|
|
Upper Usk
Valley
|
0.0 million tonnes
|
23.3 million tonnes
|
23.3 million tonnes
|
|
Total
|
111.6
million tonnes
|
281.4
million tonnes
|
393.0
million tonnes
|
|
|
|
|
|
Secondary materials from South East Wales
6.14
It is estimated (see, for
example, BGS Technical Report WF/00/3/C page 4) that 35-45% of the material dug
in Pennant Sandstone quarries and 25% of the material from limestone quarries
comprises fines. Most limestone fines are currently used in concrete and in
applications such as Macadams (roadbase and base course material, in
combination with marine sand), but not all Pennant Sandstone fines find a
beneficial use, and some are stockpiled. Figure 5.7 shows the locations of the
five existing Pennant Sandstone quarries.
6.15
This study concentrates on the
Pennant Sandstone fines (rather than limestone fines, which are already very
heavily used), since they represent the more readily accessible source of 'new'
material. For the purposes of this study the lower end of the fines range (i.e.
35%) has been used for estimating how much material is produced which might be
more fully utilised.
6.16
BGS Technical Report WF/00/3/C
notes that Pennant Sandstone crusher fines are "… not considered a waste
material but are treated as a residue of the crushing and screening process,
which can be sold into certain markets. The restrictions are specifications and
costs … some may be used locally on site in the construction of landscaping
features or in site restoration". One of the market segments into which
Pennant Sandstone fines are sold is asphalt making, reflecting their polish
resistant properties.
6.17
In principle, as recognised
both in the BGS report and in the earlier Symonds report on land-based
extraction, it might be possible to screen more of this material to yield a
concreting sand. However, screening alone would not be enough to render the
sand-like material suitable. This is because:
(i)
crushed rock sands typically
have a different size distribution than natural sand, with more fines and more
large grains, and a deficiency in the middle size range (from
0.15-2.00 mm);
(ii)
Pennant Sandstone fines in
particular contain mainly very fine grains with even fewer grains in the middle
and upper size ranges than other crushed rock samples;
(iii)
Pennant Sandstone fines also
contain small amounts of coal and clay minerals, predominantly in the smallest
fines fraction (<0.075 mm), which could be deleterious for use in
concrete, and would need to be removed.
(Figure 6.3 to be inserted here)
6.18
The BGS report notes that
"… if the finer grain sizes are removed by washing, the material is then
too coarse for most applications, due to the lack of 'medium grained' material.
The coarse fractions cause workability problems and crushed rock sand is hence
not used for building sand (it is too 'harsh')".
6.19
A separation process based on
washing/flotation would bring its own problems related to the 'sogginess' of
the washed material. Air separation might overcome these problems if the
necessary machinery could be developed, but there is no prospect of this in the
forseeable future. Most industry sources remain to be convinced about the
practicalities of producing any significant amounts of sand substitute from
Pennant Sandstone fines without investing in very expensive processing
machinery, but screening the as-dug rock prior to feeding the primary crusher
shows some evidence of raising the quality and useability of the crusher fines
which are an unavoidable by-product of the roadstone production process.
6.20
It should also be recognised
that washing out the coal and clay fractions would also inevitably involve
significant volumes of water. Even with maximum recycling and recovery, there
would be a need for fresh water, and a need to discharge some of the water at the
end of the process.
6.21
Whereas using fines from
Pennant Sandstone quarries involves using an under-utilised material, another
alternative would be to quarry other, weaker rock types for the specific
purpose of grinding it up to a sand-like size distribution. Although
considerable energy would be required to grind the rock, provided the source
rock had been correctly chosen in the first place it might not require further
processing to remove impurities such as coal and clay minerals.
6.22
The BGS investigated a range of
potential locations for hard rock quarries for this specific purpose in 2000.
This is the primary focus of Technical Report WF/00/3/C. As well as using
geological mapping to draw general conclusions about the distribution and
availability of resources, they collected samples from a range of accessible
outcrops, which they submitted for laboratory testing.
6.23
They concluded (see the
Executive Summary) that "… the Devonian strata produced crushed rock sands
which are likely to be too fine grained for use in concrete and related
applications, although a few samples from both the Senni Formation and the
Brownstones gave more acceptable results. However, the crushed rock sands
produced from the samples of Carboniferous sandstones - the Basal Grit, the
Farewell Rock and the unnamed sandstones of the Lower and Middle Coal Measures
- gave gradings which are mostly within the required limits for concreting
sands. These sandstones are therefore likely to be the best targets for
manufacturing sand from hard-rock resources in South East Wales".
6.24
A significant proportion of the
BGS' sampling and investigations related to locations in Carmarthenshire, and
which therefore lie outside the scope of this study. However, their general
conclusion holds good for the rocks which are found in a relatively narrow band
along the outer edge of the coalfield. This band runs in a massive arc from
north of Bridgend, past Caerphilly, to the west of Cwmbran and northwards to
Blaenavon. From there it turns westwards, running along the heads of the
valleys, close to the southern border of the Brecon Beacons National Park.
6.25
Within the study area, some of
the technically best samples tested by BGS came from the area around Blaenavon.
Relatively few samples from the Lower Rhymney valley were tested, and none from
the area to the west of Cwmbran. A further potential area lies to the east of
Newport and north of Chepstow. No samples from this area were tested, because
there are few if any surface outcrops of carboniferous rock that enable samples
to be collected relatively easily.
6.26
Other minor secondary aggregate
materials available (and used) within South East Wales include ground glass and
rubber crumb (from tyres). Such materials have limited application as
substitutes for primary aggregate in some specialist applications (such as road
construction or general fill), but not as a substitute for marine-dredged sand.
Ground glass, for example, can be used as 6 to 14 mm chippings within road
surfacing materials, but is generally not produced as a sand grade material.
These sources are therefore not considered further in this study.
Out-of-area materials
6.27
An alternative, which lies
midway between using Pennant Sandstone fines and specially quarried crushed
rock, would be to make greater use of the fines from an existing hard rock
quarry elsewhere, such as Foster Yeoman's coastal quarry at Glensanda (in
Scotland), or Tarmac's Bantry Bay coastal quarry (in Ireland). This would
involve using material from the fraction which currently goes to low value applications
(or is stockpiled, effectively as waste), but it would involve long-distance
transport.
6.28
Material from the Bantry Bay
gritstone quarry, like Pennant Sandstone, contains impurities which would need
to be removed before the crushed rock sand could be used in concrete. Glensanda
therefore represents the more straightforward option.
6.29
Glensanda currently exports
crushed rock to continental Europe and crushed rock sand to the South East of
England in large boats. Limited tonnages are also supplied in small boats to
South East Wales for use in block manufacture, so Foster Yeoman has access to
the necessary logistical support to arrange for additional deliveries of
material in whatever boat sizes might be required. A reasonable working
hypothesis would be for limited additional shipments to be made in boats of the
same size as existing ones, rather than in larger boats.
6.30
None of the crushed rock
options would produce a substitute for sand for use in mortar or plaster. Using
crushed rock in concrete also reduces the workability of the mixture, and
increases the demand for both water and cement.
6.31
The only very large-scale
resource of waste sand in the UK is in Cornwall and west Devon, at the china
clay quarries to be found there. Every tonne of 'good' china clay generates
roughly 900 kg of micaceous residue (very fine sand and mica), 3.7 tonnes
of coarse china clay sand (quartz silicate), and 2 tonnes each of waste rock
and overburden. Although the ratio between 'good' material and micaceous
residue is reasonably constant, the amounts of coarser wastes can vary
considerably from pit to pit. Typically, the deeper the pit, the more waste is
generated.
6.32
Some of the coarse china clay
sand is already used, mainly in Cornwall, as a fine aggregate, in concrete and
in block manufacture. The economics of re-use or recovery are almost entirely
dominated by the distance between the quarry and the main markets for
aggregates, because the materials which can be produced are of a relatively low
value. However, there are also very substantial waste tips, some of which are
constraining the development of new china clay areas. These tips are physically
distinct from the tailings ponds into which the very fine micaceous residue is
pumped in order to separate the solids from the liquid by natural gravity.
6.33
The factor which has
traditionally stopped china clay sand being shipped to areas of the UK in
deficit for sand has been the transport cost. The railway link over the Tamar
cannot take large freight trains, and road transport is both excessively costly
and environmentally damaging.
6.34
In 2000, following investments
in new infrastructure, china clay was shipped by sea to the South East of
England on a trial basis by Atlantic Aggregates Ltd of St Austell. They already
view South East Wales as a target market for future development.
6.35
The material would arrive by
sea. The size of each shipment would be limited to a maximum of 3,000 tonnes by
the dimensions of the harbour at Par. Material is available at a price of £5
per tonne free on board (fob) Par. It is currently being used as building sand
(in conformity with BS 1200 - Building sands from natural sources) as well
as for the manufacture of concrete and concrete blocks, as a filler in black
top, as chippings and as hardcore. According to 'The reclaimed and recycled
construction materials handbook' (CIRIA publication C513, 1999), china clay
sand used in concrete "… has a high water demand, which reduces the
concrete strength. This is compensated by adding cement, which, in turn,
increases the cost of the mix". Cement manufacture is an energy intensive
process, so the environmental consequences of higher cement use have to be
considered. Energy issues are considered further in Appendix 6, and the main
sustainability assessment is reported in Chapter 8.
6.36
One further option involves
importing significantly larger volumes of mixed sand and gravel from quarries
in England, either by road, or by rail. Material imported by rail would either
be blended at the rail head, or transferred to trucks for final distribution by
road. It is unlikely that imports would be on a sufficient scale to justify
rail transport.
6.37
If imports were on the sort of
scale necessary to provide building sand as well as concrete aggregate (which
is unlikely), some of the sand would need to be screened for separate use. The
remaining gravel fraction could conceivably be mixed with crushed rock sand for
use in concrete.
6.38
A final option, which remains
speculative, concerns the recovery of foundry sand from old foundry landfills.
It is known that the castings industry in South East Wales is small, but it was
probably more extensive from the 1940s to the 1970s. Evidence from England
shows that some engineering works simply dumped spent foundry sand in on-site
dedicated landfills, not realising its aggregate potential. Where such
landfills exist, recovering the material is relatively easy provided access is
reasonable. This assumes that the landfill has not been built on, and has not
been revegetated in a manner that makes it ecologically valuable.
6.39
Some development work using
foundry sand in applications such as concrete block manufacture and 'blacktop'
has been carried out, as reported in 'The reclaimed and recycled construction
materials handbook' (CIRIA publication C513, 1999). However, concrete companies
report some limitations on its use in concrete, mainly due to the presence of
heavy metals and clay.
6.40
Because of the uncertainties
surrounding the availability of foundry sand it has not been built into the
alternative patterns of supply. However, it is recommended that MPAs be
encouraged to identify any such resources in their planning areas for potential
future recovery.
6.41
Other secondary aggregate
materials, such as slate waste, are not really relevant here, because they
cannot be used as a substitute for marine sand. If the transport constraints
can be overcome, slate waste is most likely to be used in relatively low grade
applications such as bulk fill. With processing, some slate waste can be used
as a light-weight aggregate. A report on the potential for re-using slate waste
has been published by the Assembly under the title 'North Wales Slate Tips - A
Sustainable Source of Secondary Aggregates' (Arup, 2001).
Three Potential
Alternative Patterns of Supply
Introductory comments
6.42
As explained in Chapter 4, the
three alternative scenarios are based on the following policy events and
assumptions:
(i)
an end to the dredging of sand
from Nash Bank, without any sand and gravel quarries being opened in South East
Wales, and without any additional dredging licences being issued for dredging
in the Bristol Channel;
(ii)
an end to the dredging of sand
from both Nash Bank and Helwick Bank, again without any new sand and gravel
quarries being opened in South East Wales, but with two additional dredging
licences being issued, permitting new dredging further offshore in the Bristol
Channel;
(iii)
an end to the dredging of sand
from both Nash Bank and Helwick Bank, but with sand and gravel and crushed rock
quarries being permitted at various locations in South East Wales if required,
and with two additional dredging licences being issued, permitting new dredging
further offshore in the Bristol Channel.
6.43
The baseline position was set
out at the end of Chapter 5, and has been summarised for ease of reference in
Figure 6.4.
|
Figure 6.4
|
Pattern of
Supply No. 1 (tonnes)
|
|
Material
|
Used
in concrete
|
Coarse
sand
|
Fine
sand
|
Graded
aggregate
|
Ungraded
aggregate or fill
|
|
Marine-dredged
sand
|
547,200
|
273,600
|
273,600
|
0
|
45,600
|
|
Limestone dust
|
273,600
|
60,000
|
40,000
|
0
|
0
|
|
Other crushed
limestone
|
1,647,912
|
0
|
0
|
2,158,866
|
719,622
|
|
Pennant
Sandstone roadstone
|
0
|
0
|
0
|
200,000
|
0
|
|
Pennant
Sandstone fines
|
3,156
|
28,404
|
0
|
0
|
284,040
|
|
Sand and
gravel from local quarries
|
0
|
0
|
0
|
0
|
0
|
|
Crushed rock
sand from local quarries
|
0
|
0
|
0
|
0
|
0
|
|
China clay
sand
|
0
|
0
|
0
|
0
|
0
|
|
Crushed rock
sand from Glensanda
|
0
|
0
|
40,000
|
0
|
0
|
|
Imported sand
and gravel
|
100,000
|
0
|
0
|
0
|
0
|
|
Power station
fly ash
|
0
|
0
|
0
|
0
|
25,000
|
|
Air cooled
blast furnace slag
|
0
|
0
|
0
|
107,500
|
0
|
|
Minestone
|
0
|
0
|
0
|
0
|
5,000
|
|
Recycled
C&D waste
|
0
|
0
|
0
|
79,200
|
237,600
|
|
Maintenance
dredging materials
|
0
|
0
|
0
|
0
|
50,000
|
|
Total
|
2,571,868
|
362,004
|
353,600
|
2,545,566
|
1,366,862
|
|
|
|
|
|
|
|
6.44
Pattern of Supply No. 2
involves the replacement of some (but not all) of the sand currently dredged
from Nash Bank. This is because economic theory is clear regarding what happens
when a step-change event occurs which restricts supplies of a commodity: the
price rises and the quantity traded falls. Since this is an important point,
and one that is easily forgotten, the theory behind it is explained here.
6.45
Most people are familiar with
the very basic principles of supply and demand. At any point in time producers
of a commodity respond to higher prices by supplying more, while consumers
respond by demanding less. There is only one stable price (the 'market clearing
price') at which supply and demand are in balance (see Figure 6.5, where P0
is the market clearing price, and Q0 is the amount which consumers
want to buy and suppliers to sell at P0). Any temporary departure
from P0 or Q0
causes disruption, but eventually the market settles back to the same balance
between supply and demand.
|
Figure 6.5
|
'Classic' supply and
demand equilibrium
|
|
Price
|
|
|
|
|
|
|
|
|
|
P0
|
|
|
|
|
|
|
Q0
|
Quantity
|
|
|
|
|
|
6.46
A step-change event is
different. A step-change event involves a significant change either in
consumers' desire to buy the product, or in producers' ability to supply the
previous volume at the previous market clearing price. Examples of step-change
events are:
(i)
the introduction of significant
new technology (making it possible for producers to make the product more
cheaply, thereby enabling them to cut their prices, stimulating greater demand
from consumers);
(ii)
the arrival of a new competing
product (this changes the amount that consumers want to buy, because if the new
product is attractive, they use money that previously would have purchased the
'old' commodity: for example the arrival of oranges permanently changed the
demand for apples);
(iii)
the granting of a subsidy to
consumers by government (which raises the amount which they want to buy,
without changing producers' preferences at all).
6.47
These step-changes are all
expressed as a shift in one or other of the curves in the basic supply and
demand model. New technology would shift the supply curve to the right (i.e.
producers are happy to make more than before at the same price). A new
competitor for consumers' cash would shift the demand curve to the left (i.e.
consumers want less than before at the same price). A consumer subsidy would
shift the demand curve to the right (i.e. consumers want more at the old shelf
price, because someone else is paying part of the cost).
6.48
Taking some or all of the
marine-dredged sand away from the aggregate equation of South East Wales
amounts to shifting the supply curve upwards and to the left (see Figure 6.6).
It does not affect consumers' preferences (their demand curve stays still), but
the market clearing price rises from P0 to P1. As a
consequence, the volume of material that consumers want to buy falls from Q0
to Q1.
6.49
This is a long-winded way of
explaining that in the absence of a directly comparable source of supply,
restricting or removing marine-dredged sand from the supply side of the
equation in an otherwise free market will raise prices for sand in South East
Wales and reduce its consumption. Some consumers may adopt different
construction systems; others will build less. The market will not, however,
simply bring in as much sand as before from elsewhere at a higher price, except
in the short term to meet unavoidable contractual obligations.
|
Figure 6.6
|
Establishment of a new
supply and demand equilibrium after a step change in supply
|
|
Price
|
|
|
|
|
P1
|
|
|
|
|
P0
|
|
|
|
|
|
Q1
|
Q0
|
Quantity
|
|
|
|
|
|
6.50
Examples of likely adaptation
behaviour which would help to reduce the volume of sand demanded would include:
(i)
greater use of steel in place
of concrete in both buildings and civil engineering structures;
(ii)
greater use of wood and metal
cladding in place of brick facing in buildings;
(iii)
greater use of wood and gravel
in the garden DIY market (e.g. by building fences and decking and installing
gravel paths in preference to garden walls and paved patios/paths).
6.51
Reflecting this piece of
theory, Pattern of Supply No. 2 does not involve as much sand as the
baseline position.
6.52
In constructing the proposals
for Patterns of Supply Nos. 2-4 due note has been taken of the findings of
the earlier Symonds report on land-based extraction. Reflecting the economic
modelling and analysis which was undertaken at that time, Table 6.13 in that
report ranked the potential supply options on the basis of their probable ability
to compete. The findings from Table 6.13 can be summarised as follows:
(i)
the existing scenario of
marine-dredged sand and crushed limestone was adjudged to offer the best
combination of price and technical suitability;
(ii)
crushed rock fines from
existing Pennant Sandstone quarries were ranked No. 2, though the report
warned that "… processing difficulties mean that this source could
substitute for only a small proportion of the existing supply of marine-dredged
sand";
(iii)
sand and gravel from potential
new quarries in South East Wales was ranked No. 3, on the assumption that
"… several sources would need to be worked simultaneously throughout the
study area to substitute effectively for the existing combination (of
materials)", and "… this would have economic impacts on the existing
limestone producers";
(iv)
crushed rock from potential
hard rock sources in South East Wales was ranked No. 4;
(v)
imported china clay sand from
Cornwall was ranked No. 5, and adjudged to be "… a marginally viable
prospect";
(vi)
imported crushed rock fines
from Glensanda was ranked No. 6, though it was noted that it would "…
contribute to an increase in the cost of construction materials";
(vii)
imported sand and gravel from
land-based sources in adjoining parts of England and Wales was ranked
No. 7, mainly on the basis of "… very high transport costs"
which might be partially overcome by taking advantage of "… opportunities
for back haulage in Pennant Sandstone lorries returning to South Wales".
6.53
The alternative scenarios
underlying Patterns of Supply Nos. 2 and 3 include the assumption that no
new sand and gravel quarries (including crushed sand quarries) would be opened
in South East Wales. This therefore rules out the third and fourth ranked
options from the foregoing list. Guidance from the Steering Group has also
encouraged a more positive view to be taken towards the final option (importing
sand and gravel by road), provided the scale is not excessive. This reflects
the fact that imports already occur, and could be expanded to a modest degree
relatively easily.
Pattern of Supply No. 2
6.54
An end to dredging of sand from
Nash Bank would involve the loss of around 700,000 tonnes a year of
marine-dredged sand currently landed at Swansea, Briton Ferry, Port Talbot (a
very small amount), Barry, Cardiff and Newport. The biggest impacts would be
felt in the area between Swansea/Neath in the west and Cardiff in the east,
since these markets are almost entirely dependent for their supplies of sand on
Nash Bank.
6.55
Dredging from Helwick Bank has
been at a rate of roughly 90,000 tonnes a year, which is comfortably below the
permitted level of 150,000 tonnes a year. It is assumed that, in the absence of
sand from Nash Bank, the overall 'take' from Helwick Bank would be raised to
more like 140,000 tonnes a year. This would permit the 34,000 tonnes of sand
currently supplied to Pembroke from Nash Bank to be replaced by sand from
Helwick Bank, and the supply to the Swansea area market from Helwick to be
raised from 30,000 to, say, 45,000 tonnes a year.
6.56
Similarly, there is scope for
the 'take' from Holm Sands to be raised within the existing licence
constraints, from around 150,000 tonnes a year to, say, 200,000 tonnes a year.
In theory the 'take' could be raised considerably further, but there are
reported to be real technical constraints to raising it significantly.
6.57
Finally, the 'take' from Middle
Ground might be expected to rise from around 90,000 tonnes a year to, say,
125,000 tonnes a year.
6.58
The net effect of these changes
would be to reduce landings of sand within the study area by around 600,000
tonnes a year (a reduction of 700,000 tonnes from Nash Bank, partially offset
by increases from the other areas totalling around 100,000 tonnes a year).
6.59
The employment and
environmental effects of these changes are considered in Chapter 8.
6.60
Based on market 'feel' (as
opposed to complex modelling), it has been assumed that this step change in the
supply pattern (namely a loss of over half of current supplies of
marine-dredged sand before any resultant adjustments involving other materials)
would lead to a noticeable price rise for sand, and a reduction in the volume
bought by users. The volume reduction has been assumed to be 7.5%.
6.61
Including the adjustments
described above, it is assumed that the overall response of the companies
operating in the market would be broadly as follows:
(i)
an extra 100,000 tonnes of sand
a year would be supplied to the study area from Helwick Bank, Holm Sands and
Middle Grounds, leaving a shortfall of 600,000 tonnes of marine-dredged sand
compared to the baseline position;
(ii)
no sand at all would be used as
fill;
(iii)
more limestone would be crushed
to dust/fines, with a small (roughly 2.5%) increase in the overall demand for
limestone;
(iv)
all (as opposed to much)
concrete made with marine-dredged sand would also include the maximum
contribution from limestone dust/fines;
(v)
greater use would be made of
limestone dust/fines in other applications currently supplied by marine-dredged
sand;
(vi)
a modest contribution would be
made by Pennant Sandstone fines in applications such as concrete, 'blacktop'
and block making, without increasing the total amount of sandstone quarried.
Most would still be used for bulk fill or quarry restoration;
(vii)
imports of Cornish china clay
sand for use in concrete and as a coarse building sand would start (at a rate
of one small boat a week, say 130,000 tonnes a year, delivered to several or
all of the ports);
(viii)
imports of mixed sand and
gravel would rise by 50% (to 150,000 tonnes a year, all being delivered by
road), with all of this material used in concrete (as at present);
(ix)
in addition to material
supplied for block making, a small share of the demand for concrete sand and
fine building sand would be met from crushed rock sand imported from Glensanda,
delivered in small boats to a range of ports;
(x)
10,000 tonnes of fine sand
which is already dredged from the river Neath would be landed at Briton Ferry
and utilised in construction.
6.62
Figure 6.7 contains a set of
specific numbers which are consistent with the above principles. Those numbers
which differ from Pattern of Supply No. 1 are shown in bold.
|
Figure 6.7
|
Pattern of
Supply No. 2 (tonnes)
|
|
Material
|
Used
in concrete
|
Coarse
sand
|
Fine
sand
|
Graded
aggregate
|
Ungraded
aggregate or fill
|
|
Marine-dredged
sand
|
339,460
|
53,160
|
147,380
|
0
|
0
|
|
Limestone dust
|
339,460
|
160,000
|
90,000
|
0
|
0
|
|
Other crushed
limestone
|
1,460,834
|
0
|
0
|
2,158,866
|
809,362
|
|
Pennant
Sandstone roadstone
|
0
|
0
|
0
|
200,000
|
0
|
|
Pennant
Sandstone fines
|
10,000
|
20,000
|
35,700
|
0
|
249,900
|
|
Sand and
gravel from local quarries
|
0
|
0
|
0
|
0
|
0
|
|
Crushed rock
sand from local quarries
|
0
|
0
|
0
|
0
|
0
|
|
China clay
sand
|
21,497
|
108,324
|
0
|
0
|
0
|
|
Crushed rock
sand from Glensanda
|
20,000
|
0
|
60,000
|
0
|
0
|
|
Imported sand
and gravel
|
150,000
|
0
|
0
|
0
|
0
|
|
Power station
fly ash
|
0
|
0
|
0
|
0
|
25,000
|
|
Air cooled
blast furnace slag
|
0
|
0
|
0
|
107,500
|
0
|
|
Minestone
|
0
|
0
|
0
|
0
|
5,000
|
|
Recycled
C&D waste
|
0
|
0
|
0
|
79,200
|
237,600
|
|
Maintenance
dredging materials
|
0
|
0
|
10,000
|
0
|
40,000
|
|
Total
|
2,341,251
|
341,484
|
210,900
|
2,545,566
|
1,366,862
|
|
|
|
|
|
|
|
Pattern of Supply No. 3
6.63
An end to dredging of sand from
both Nash Bank and Helwick Bank would involve the loss of around 730,000 tonnes
a year of marine-dredged sand from the South East Wales market. The adjacent
South West Wales market would also lose around 70,000 tonnes from Helwick Bank
and 34,000 tonnes from Nash Bank.
6.64
Where Pattern of Supply
No. 3 differs significantly from No. 2, however, is that in
No. 3 it is assumed that the applications to dredge from both Nobel Banks
and Culver Sands would be approved, though not necessarily with the upper
annual tonnage limits as proposed. Both applications refer wholly or largely to
sediment areas where the Assembly is inclined to take a broadly favourable view
on applications to dredge (Policy 1).
6.65
The application to dredge from
Nobel Banks is for 300,000 tonnes a year, and the application for Culver Sands
is for 1.5 million tonnes a year. As a working hypothesis, this Pattern of
Supply assumes that the maximum annual 'takes' are set at the same levels as
those which apply to Helwick Bank and Nash Bank respectively (i.e. 150,000
tonnes a year for Nobel Banks, and 900,000 tonnes a year for Culver Sands),
enabling the resources to last significantly longer as a consequence.
6.66
It is known that the resources
on Holm Sands are becoming increasingly difficult to recover. Whereas Pattern
of Supply No. 2 assumes that they would have to be dredged in order to
make up for the loss of Nash Bank, in Pattern of Supply No. 3 it is
assumed that the rate of 'take' from Holm Sands would continue to decline.
6.67
So long as dredging from Middle
Ground and Bedwin Sands continues at roughly the current rate, Nobel Banks and
Culver Sands would be able to make up the full shortfall from ceasing to dredge
Helwick and Nash Banks, and from reducing the 'take' from Holm Sands. Pattern
of Supply No. 3 assumes that the combined 'take' from Holm Sands and Middle
Ground would be 200,000 tonnes a year. Combined with 150,000 tonnes a year from
Bedwin Sands, this would mean that 350,000 tonnes a year would be from close to
shore, with the balance (790,000 tonnes a year) from further offshore.
6.68
Therefore, the only difference
between Pattern of Supply No. 3 and the base case would be the move from
near-shore to offshore dredging, and the consequent changes in impacts on the
marine environment and the use of energy resulting from the greater travel
distances involved.
Pattern of Supply No. 4
6.69
As for Pattern of Supply
No. 3, an end to dredging of sand from both Nash Bank and Helwick Bank
would involve the loss of around 730,000 tonnes a year of marine-dredged sand
from the South East Wales market, and the loss of around 104,000 tonnes a year
from the adjacent South West Wales market.
6.70
Pattern of Supply No. 4
assumes that new licences are issued for dredging further offshore, and that
new sources of land-based supply are approved. However, with the availability
of land-based sand and gravel, it is assumed that the maximum annual 'takes'
from Nobel Banks and Culver Sands are set at 75% of the levels included in
Pattern of Supply No. 3, (i.e. 112,500 tonnes a year for Nobel Banks, and
675,000 tonnes a year for Culver Sands), enabling the resources to last
significantly longer as a consequence.
6.71
Since the tonnage dredged is
seldom if ever equal to the upper limit set in the licence, it is assumed that
the actual tonnage supplied to the study area from Nobel Banks would be
unchanged from the base case (30,000 tonnes), and that the actual tonnage
supplied from Culver Sands would be 520,000 tonnes a year (excluding 34,000
tonnes a year supplied to Pembroke, as at present).
6.72
The assumptions regarding Holm
Sands, Middle Ground and Bedwin Sands are the same as they were in Pattern of
Supply No. 3 (i.e. that they would provide no more than 350,000 tonnes a
year between them).
6.73
The net effect would be 350,000
tonnes a year from close to shore, and 550,000 tonnes a year from further
offshore: a total of 900,000 tonnes a year of marine-dredged sand, or a
reduction of 240,000 tonnes a year compared to the base case.
6.74
Including the adjustments
described above, it is assumed that the overall response of the companies
operating in the market would be broadly as follows:
(i)
900,000 tonnes of sand a year
would be dredged, 350,000 tonnes from close to shore and 550,000 from further
offshore, leaving a shortfall of 240,000 tonnes of marine-dredged sand compared
to the baseline position;
(ii)
no sand at all would be used as
fill;
(iii)
imports of mixed sand and
gravel from England would cease, and be replaced by just under 350,000 tonnes a
year of sand and gravel from three newly-developed quarries in South East Wales
(one to the north of Swansea, one between Port Talbot and Pyle, and the third
in the Pontyclun-Cowbridge area), with all of this material used in concrete;
(iv)
all (as opposed to much)
concrete made with marine-dredged sand would also include the maximum
contribution from limestone dust/fines, though the total demand for crushed
limestone would fall slightly;
(v)
the contribution made by
Pennant Sandstone fines and crushed rock sand from Glensanda in applications
such as concrete, 'blacktop' and block making would remain unchanged.
6.75
Figure 6.8 contains a set of
specific numbers which are consistent with the above principles. Those numbers
which differ from Pattern of Supply No. 1 are shown in bold.
|
Figure 6.8
|
Pattern of
Supply No. 4 (tonnes)
|
|
Material
|
Used
in concrete
|
Soft
sand
|
Sharp
sand
|
Graded
aggregate
|
Ungraded
aggregate or fill
|
|
Marine-dredged
sand
|
352,800
|
273,600
|
273,600
|
0
|
0
|
|
Limestone dust
|
352,800
|
60,000
|
40,000
|
0
|
0
|
|
Other crushed
limestone
|
1,417,512
|
0
|
0
|
2,158,866
|
765,222
|
|
Pennant
Sandstone roadstone
|
0
|
0
|
0
|
200,000
|
0
|
|
Pennant
Sandstone fines
|
3,156
|
28,404
|
0
|
0
|
284,040
|
|
Sand and
gravel from local quarries
|
349,090
|
0
|
0
|
0
|
0
|
|
Crushed rock
sand from local quarries
|
0
|
0
|
0
|
0
|
0
|
|
China clay
sand
|
0
|
0
|
0
|
0
|
0
|
|
Crushed rock
sand from Glensanda
|
0
|
0
|
40,000
|
0
|
0
|
|
Imported sand
and gravel
|
0
|
0
|
0
|
0
|
0
|
|
Power station
fly ash
|
0
|
0
|
0
|
0
|
25,000
|
|
Air cooled
blast furnace slag
|
0
|
0
|
0
|
107,500
|
0
|
|
Minestone
|
0
|
0
|
0
|
0
|
5,000
|
|
Recycled
C&D waste
|
0
|
0
|
0
|
79,200
|
237,600
|
|
Maintenance
dredging materials
|
0
|
0
|
0
|
0
|
50,000
|
|
Total
|
2,475,358
|
362,004
|
353,600
|
2,545,566
|
1,366,862
|
|
|
|
|
|
|
|
The Differences between
the Current and Alternative Patterns of Supply
6.76
Some supply options and sources
remain constant across all four patterns of supply. These elements are as
follows:
(i)
Pennant Sandstone used as high
quality roadstone aggregate;
(ii)
crushed hard rock sand from
local sources (zero in all cases);
(iii)
power station ash;
(iv)
steel slag;
(v)
minestone;
(vi)
recycled aggregate.
6.77
The supply sources that vary
are the following:
(i)
marine-dredged sand (from close
to shore);
(ii)
marine-dredged sand (from
mid-Channel);
(iii)
limestone dust;
(iv)
other crushed limestone;
(v)
Pennant Sandstone fines used as
a sand substitute;
(vi)
locally quarried sand and
gravel;
(vii)
china clay sand from Cornwall;
(viii)
crushed hard rock sand from
Glensanda;
(ix)
imported sand and gravel from
England delivered by road;
(x)
maintenance dredging materials.
6.78
Figure 6.9 shows the differences
between the four patterns of supply for these specific combinations of supply
options and source locations. In practice the use of both crushed limestone and
Pennant Sandstone fines is very similar in all four cases.
6.79
It has to be stressed that these
are not intended to be fully detailed predictions of what would happen under
each of the alternative policy scenarios, and the assumptions which are
described here are not intended in any way to reflect on the merits or
otherwise of the various applications to dredge marine sand from the Bristol
Channel which are currently being considered by the Assembly. They are intended
to be credible approximations to what might happen following a period of
adjustment, with enough variation to bring out differences in the four patterns
of supply when they are compared.
|
Figure 6.9
|
Relationship
between individual supply options and four proposed patterns of supply
(tonnes)
|
|
Supply
options
|
Patterns
of supply
|
|
1
|
2
|
3
|
4
|
|
Marine-dredged
sand (from close to shore)
|
1,122,000
|
522,000
|
350,000
|
350,000
|
|
Marine-dredged
sand (from mid-Channel)
|
18,000
|
18,000
|
790,000
|
550,000
|
|
Limestone dust
from local quarries
|
373,600
|
589,460
|
373,600
|
452,800
|
|
Other crushed
limestone (local)
|
4,526,400
|
4,429,062
|
4,526,400
|
4,341,600
|
|
Locally
quarried Pennant Sandstone fines
|
315,600 (284,040 as fill)
|
315,600 (249,900 as fill)
|
315,600 (284,040 as fill)
|
315,600 (284,040 as fill)
|
|
Locally
quarried sand and gravel
|
0
|
0
|
0
|
349,090
|
|
China clay
sand from Cornwall
|
0
|
129,821
|
0
|
0
|
|
Crushed rock
sand from Glensanda
|
40,000
|
80,000
|
40,000
|
40,000
|
|
Imported
English sand and gravel
|
100,000
|
150,000
|
100,000
|
0
|
|
Maintenance dredging materials
|
50,000
(all as fill)
|
50,000
(40,000 as fill)
|
50,000
(all as fill)
|
50,000
(all as fill)
|
|
|
|
|
|
|
Choosing a Set of
Representative Sites
Introductory comments
7.1
In order to compare the four
patterns of supply using a sample of representative sites, it was necessary to
select sites which represent all significant elements of the baseline Pattern
of Supply No. 1, plus sites which represent all significant additions
proposed in all of the alternatives. It was also necessary to achieve a
reasonable balance between urban and rural settings, and between different
parts of the study area.
7.2
Furthermore, it was agreed that
some of the supply options which have not been actively pursued in the patterns
of supply should also be treated on a similar basis, so that if they needed to
be considered in future, the necessary information is available.
7.3
Taking all of these
considerations into account, the sites which were chosen are described below
and listed in Figure 7.1.
Marine-dredged sand and sea-borne imports
7.4
Although site visits could not
be made to the offshore dredging locations, Nash Bank was viewed from the adjacent
cliffs, and visits were made to some of the beaches which have generated
particular concern as part of the review of coastal processes.
7.5
Visits were made to the sand
wharves at Newport and Briton Ferry. These visits were organized primarily to
cover the land-based impacts arising from the handling and dispatch of dredged
sand, and to allow additional discussions with the dredging companies about
operational impacts unrelated to coastal processes.
7.6
The local land-based impacts of
potential imports of crushed rock from Glensanda and china clay sand from
Cornwall were covered in part through discussions with ABP at Swansea, in part
by speaking to the producing companies, and in general terms by the visits to
the sand wharves (see above).
Quarries
7.7
Existing limestone quarries
were represented by two sites: one large and the other medium-sized, one close
to an urban area and the other in a more rural setting. Both quarries have
processing facilities to enable them to ship a range of aggregate products.
7.8
Visits were also made to two
Pennant Sandstone quarries, both to look at their existing operations, and to
look at the potential for expanding the processing of fines.
7.9
Even though at the point that
visits were being arranged it was thought unlikely that a hard rock quarry in
South East Wales would finally be included within any of the Patterns of
Supply, one potential quarry location was visited.
7.10
Six sites identified in the
previous Symonds study as possible locations for future sand and gravel
quarries in South East Wales were visited, and operational information was
gathered from comparable quarrying operations in England. The six sites are
geographically widely spread, and occupy a range of settings (urban and rural,
constrained by planning and environmental designations and unconstrained). Four
are in valley bottoms, and two are more typical of glacial deposits.
Other materials
7.11
Although no changes were
expected in the use of recycled demolition waste materials, one representative
site was visited. No site visits related to maintenance dredging were
organized, but some discussions were held with interested parties.
7.12
Discussions were held with
Corus about the possibility of visiting the unused portion of the Llanwern
steel works in order to see if it might offer some potential for a major
aggregate handling centre for primary, secondary and recycled aggregate. This
was not pursued when it became clear that this might well have adverse
operational impacts on the remaining steel processes, and on Corus' own
proposals for the redevelopment of the remainder of the site.
|
Figure 7.1
|
Representative
sites assessed through site visits
|
|
No.
|
Site
|
Justification
|
|
1
|
Nash Bank (off
Vale of Glamorgan) and nearby beaches
|
Largest source
of marine-dredged sand, clearly visible from cliff tops at Nash Point (as a
complement to extensive data review).
|
|
2
|
Sand wharves
at Newport
|
Important
urban port for landing marine-dredged sand towards the east of the study
area.
|
|
3
|
Sand wharves
at Briton Ferry (Neath-Port Talbot)
|
Important but
relatively rural river wharves for landing marine-dredged sand in the west of
the study area.
|
|
4
|
Port of
Swansea
|
Potential
landing point for alternative materials, in the west of the study area. Under
the same management as Port Talbot.
|
|
5
|
Wenvoe (Vale
of Glamorgan)
|
Major existing
limestone quarry close to an urban centre.
|
|
6
|
Penhow
(Newport)
|
Medium
existing limestone quarry in a more rural setting.
|
|
7
|
Hafod
(Caerphilly)
|
Pennant
Sandstone quarry towards the east of the study area.
|
|
8
|
Cwm Nant
Lleici (Neath-Port Talbot)
|
Pennant
Sandstone quarry to the west of the study area.
|
|
9
|
Site south of
Blaenavon (Torfaen)
|
Potential hard
rock quarry for producing crushed rock sand.
|
|
10
|
Site west of
Aberystwyth (Brecon Beacons NP)
|
Potential sand
and gravel quarry in the Usk valley to the north of the study area, in a
rural setting, with multiple planning designations, including the Brecon
Beacons National Park.
|
|
11
|
Site south of
Usk (Monmouthshire)
|
Potential sand
and gravel quarry in the Usk valley to the east of the study area, in a rural
setting, constrained by planning designations and possible flooding.
|
|
12
|
Site near
Lower Machen (Newport)
|
Potential sand
and gravel quarry in the Rhymney valley to the east of the study area, in a
rural setting, constrained by a major aquifer and possible flooding.
|
|
13
|
Site north of
Cowbridge (Vale of Glamorgan)
|
Potential sand
and gravel quarry in the Thaw valley near the centre of the study area, in a
rural setting, unconstrained by planning designations.
|
|
14
|
Site east of
Pontarddulais (Swansea)
|
Potential sand
and gravel quarry exploiting glacial deposits to the west of the study area,
in a rural setting, unconstrained by planning designations.
|
|
15
|
Site west of
Pyle (Neath-Port Talbot)
|
Potential sand
and gravel quarry exploiting glacial deposits in the west/centre of the study
area, close to an urban area, unconstrained by planning designations.
|
|
16
|
Site south east of Cardiff
|
Recycling centre for construction and
demolition waste on the urban fringe.
|
|
|
|
|
Assessing the Chosen
Sites
7.13
With the exception of the visit
to Nash Point, all site visits took place during the week 15-19 October 2001.
The non-Nash site visits involved a full team of specialists from Symonds in:
(i)
environmental geology and
impacts on the water environment (Dr Alan Thompson);
(ii)
noise, vibration and air
quality (David Leversedge);
(iii)
landscape, visual and amenity
impacts and ecology (Roger Cooper);
(iv)
land use planning and
transportation (Peter Hine);
(v)
economics, environmental
management and sustainability (David Knapman).
7.14
The site visits divided roughly
equally between 'real' activities on 'actual' sites and 'potential' activities
on 'theoretical' sites. This second group required some assumptions to be made.
In this respect the approach that was taken had much in common with a screening
process for selecting a preferred site for a development project. All of the
sites were assessed using the prompt list set out in Appendix 3, ignoring those
questions which did not apply to the specific case under consideration.
7.15
Given that some of the sites
related to just one part of a supply chain, and that more than one example of
certain important elements of the supply system were included in the selection
of sites visited, the relationship between the site visits and the supply
option Case Studies which arose from them was not a simple 1:1. The supply
option Case Studies are listed in Figure 7.2, together with the linkages
between the site visits and the Case Studies. The supply option Case Studies
themselves can all be found in Appendix 9.
|
Figure 7.2
|
Supply option
Case Studies
|
|
No.
|
Title
|
Site visits contributing to the
Case Study
|
Other sources contributing to
the Case Study
|
|
1
|
Sand dredged
from Marine Aggregate Dredging Policy 2 Areas, and landed at wharves in South
East Wales
|
1, 2, 3
|
Documents
supplied by dredging companies and others
|
|
2
|
Sand dredged
from Marine Aggregate Dredging Policy 1 Areas, and landed at wharves in South
East Wales
|
2, 3
|
Documents
supplied by dredging companies and others
|
|
3
|
Aggregate from
carboniferous limestone quarries in South East Wales
|
5, 6
|
|
|
4
|
Aggregate from
Pennant Sandstone quarries
|
7, 8
|
|
|
5
|
Sand and
gravel from potential new quarries in river valley deposits in South East
Wales
|
10-13
|
Earlier
Symonds report
|
|
6
|
Sand and
gravel from potential new quarries in glacial deposits in South East Wales
|
14, 15
|
Earlier
Symonds report
|
|
7
|
Sand and
gravel imported by road from existing quarries in England
|
-
|
Information
supplied by quarrying company
|
|
8
|
Crushed rock
sand from a potential new, dedicated quarry in South East Wales
|
9
|
BGS report
|
|
9
|
Crushed hard
rock sand from Glensanda
|
4
|
Information
supplied by Foster Yeoman (company that owns Glensanda)
|
|
10
|
China clay
sand from Cornwall
|
4
|
Information
supplied by Imerys and Atlantic Aggregates
|
|
11
|
Maintenance
dredging material from the river Neath
|
2
|
Information
supplied by Neath Harbour Commissioners
|
|
12
|
Secondary and recycled aggregate
|
16
|
|
|
|
|
|
|
How the Case Studies
Contribute to the Patterns of Supply
7.16
The four patterns of supply (to
be compared and assessed for their contributions to sustainability in Chapter
8) were set out in Chapter 6. The comparisons and assessments to be made are:
(i)
Pattern of Supply No.2 compared
to Pattern of Supply No.1;
(ii)
Pattern of Supply No.3 compared
to Pattern of Supply No.1; and
(iii)
Pattern of Supply No.4 compared
to Pattern of Supply No.1.
7.17
Figure 6.9 (at the very end of
Chapter 6) sets out the differences between all four patterns of supply.
However, the comparisons between each pair of patterns of supply only needs to
take account of those elements which differ between the two, so some of the
comparisons are less complex than others.
7.18
The key differences between
each pair of patterns of supply are set out in Figure 7.3, together with
references to the directly relevant Case Studies.
|
Figure 7.3
|
Differences
between the three pairs of Patterns of Supply
|
|
Nos.
|
Differences (compared to Pattern
of Supply No. 1)
|
Case
Studies of greatest relevance, and direction of change
|
|
2 vs 1
|
Sharply
reduced dredging of sand close to shore (522,000 tonnes vs 1,122,000 tonnes).
|
Less of No. 1
|
|
Marginal (2.5%)
increase in crushed limestone production.
|
More of No. 3
|
|
Same level of
Pennant Sandstone fine production, but more diverted from fill to higher
value uses (66,000 tonnes vs 32,000 tonnes).
|
No change, No. 4
|
|
Large volume
of coarse china clay sand imported from Cornwall (130,000 tonnes vs nil).
|
More of No. 10
|
|
Twice as much
crushed rock sand imported from Glensanda (80,000 tonnes vs 40,000 tonnes).
|
More of No. 9
|
|
50% more mixed
sand and gravel imported from England (150,000 tonnes vs 100,000 tonnes).
|
More of No. 7
|
|
Same level of
maintenance dredging, but some of it used as fine building sand rather than
fill (10,000 tonnes vs nil).
|
More of No. 11
|
|
Overall
reduction (9%) in the tonnage of aggregate going into concrete (2,340,000
tonnes vs 2,570,000 tonnes).
|
n/a
|
|
3 vs 1
|
Very sharply
reduced dredging of sand close to shore (350,000 tonnes vs 1,122,000 tonnes).
|
Less of No. 1
|
|
Very sharply
increased dredging of sand from mid-Channel (790,000 tonnes vs 18,000
tonnes).
|
More of No. 2
|
|
4 vs 1
|
Very sharply
reduced dredging of sand close to shore (350,000 tonnes vs 1,122,000 tonnes).
|
Less of No. 1
|
|
Very sharply
increased dredging of sand from mid-Channel (550,000 tonnes vs 18,000
tonnes).
|
More of No. 2
|
|
Marginal (2%)
reduction in crushed limestone production.
|
Less of No. 3
|
|
Large volume
of mixed sand and gravel quarried locally (350,000 tonnes vs nil).
|
More of No. 5 and/or No. 6
|
|
Complete cessation of imports of
mixed sand and gravel from England (nil vs 100,000 tonnes).
|
No
more No. 7
|
|
|
|
|
7.19
These comparisons are worked
through in Chapter 8, using the Symonds model for assessing progress towards
sustainability, which is more fully described in Appendix 4.
(This page is intentionally blank)
Description of the
Sustainability Assessment Process
8.1
The Symonds model for assessing
progress towards sustainability is described in Appendix 4. In essence, it
works by asking 37 specific questions designed to show whether (and how) one
course of action would be expected to generate a greater or lesser impact than
an alternative. It does this for a series of environmental, social and economic
receptors and issues.
8.2
The answers to the 37 specific
questions which are posed for each 'comparison pair' are then used to evaluate
whether the change under consideration is likely to:
(i)
increase or decrease the stock
of capital of a series of environmental, social and economic resources; and
(ii)
increase or decrease the flow
of these same resources.
8.3
By looking at both stocks and
flows, the model seeks to distinguish between a large depletion in stocks which
has no impact on the rate at which resources are being drawn down, and an
equally large depletion which reduces the rate at which resources are used in
future. By way of illustration, energy expended to raise the thermal efficiency
of a process or structure is inherently less damaging, and more sustainable,
than the same amount of energy expended to build a 'business as usual' process
or structure, let alone a process or structure which is more wasteful than the
outgoing original.
Pattern of Supply
No. 2 Compared to the Current Pattern (No. 1)
8.4
Pattern of Supply No. 2 is
the pattern which might be expected to emerge if the dredging licence for Nash
Bank was withdrawn, without any sand and gravel quarries being opened in South
East Wales, and without any additional dredging licences being issued for
dredging in the Bristol Channel.
8.5
The main differences between
the two Patterns of Supply, as previously summarised in Figure 7.3, are:
(i)
a sharp reduction in dredging
of sand from close to shore (522,000 tonnes vs 1,122,000 tonnes);
(ii)
a marginal (2.5%) increase in
crushed limestone production;
(iii)
the same level of Pennant
Sandstone fine production, but with more fines being diverted away from use as
fill, and into higher value uses as a sand substitute (66,000 tonnes vs 32,000
tonnes);
(iv)
a large volume of coarse china
clay sand imported from Cornwall (130,000 tonnes vs nil);
(v)
twice as much crushed rock sand
imported from Glensanda (80,000 tonnes vs 40,000 tonnes);
(vi)
50% more mixed sand and gravel
imported from England (150,000 tonnes vs 100,000 tonnes);
(vii)
the same level of maintenance
dredging, but with some of the material used as fine building sand rather than
fill (10,000 tonnes vs nil);
(viii)
an overall reduction (9%) in
the tonnage of aggregate going into concrete (2,340,000 tonnes vs 2,570,000
tonnes).
8.6
The full sustainability
assessment of Pattern of Supply No. 2 compared to Pattern of Supply
No. 1 (the current pattern) can be found in Appendix 10. The main elements
of this comparison, and the conclusions which arise from it are illustrated in
Figure 8.1 and summarised in Figure 8.2
|
Figure 8.1:
|
'Sustainability Scorecard' for Pattern of Supply
No. 2 compared to Pattern of Supply No. 1 (the current pattern)
|
|
|
|
|
Clear
|
Increase in stock (short term)
|
|
Most
Sustainable
|
|
|
|
(2-1) (2-5) (2-10)
|
(2-12)
|
(2-7)
|
Minor
|
|
(2-2) (2-4)
|
|
|
|
|
No
|
|
|
Clear Minor
Increase in rate of use (long term)
|
change
|
Minor Clear
Decrease in rate of use (long term)
|
|
|
|
(2-9)
|
|
|
Minor
|
Decrease in
stock (short term)
|
|
|
|
|
Least
Sustainable
|
|
Clear
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
NB:
|
Only those items of capital where Pattern of
Supply No. 2 differs from the current pattern are shown.
|
|
Key:
|
(2-N)
|
Pattern of Supply No. 2, item of
capital number N (see below).
|
|
|
N
|
Item of capital
|
|
|
1
2
3
4
5
6
7
8
9
10
11
12
|
Fossil fuels
Soils and non-energy
minerals
Fresh water
Seas and oceans
Clean air and healthy
climate
Healthy ecosystems
Human health
Knowledge
Social inclusion
Housing
Means of production
Transport and energy
infrastructure
|
8.7
The sustainability gains from
Pattern of Supply No. 2 are a reduction in the rate of use (and therefore
depletion) of one group of non-renewable resources (marine sand), and a
reduction in the potential damage that might otherwise be done to the marine
and coastal environment by continued dredging from Nash Bank.
8.8
These gains are at the cost of
an increase in the rate of use of another group of non-renewable resources
(fossil fuels), and the environmental and social damage done by increased
energy consumption and lower levels of economic activity.
8.9
This is illustrated in Figure
8.1 opposite, which provides a 'sustainability scorecard' for Pattern of Supply
No. 2 compared to the current pattern of supply. The same information is
summarised in Figure 8.2 below, which provides the 'headline findings' from the
full sustainability assessment in Appendix 10.
|
Figure 8.2
|
Predicted differences in
the rates of depletion of items of environmental and human/social capital as
a result of switching from Pattern of Supply No. 1 to Pattern of Supply
No. 2
|
|
Gains
èèè
|
Clear reduction in the rate of
depletion
|
2 - Soils and non-energy minerals
4 - Seas and oceans
|
|
Neutral
|
No (or very little) change in the
rate of depletion
|
3 - Fresh water
6 - Healthy ecosystems
8 - Knowledge
11 - Means of production
|
|
Losses
ççç
|
Probably a small increase in the rate
of depletion
|
7 - Human health
|
|
Small increase in the rate of
depletion
|
12 - Transport and energy
infrastructure
|
|
Clear but small increase in the rate
of depletion
|
1 - Fossil fuels
5 - Clean air and healthy climate
9(1) - Social inclusion
10 - Housing
|
|
Note:
|
(1)
|
Together with a minor decrease in the stock of capital as a result of
increased unemployment.
|
|
|
|
|
8.10
Pattern of Supply No. 2 is
therefore not inherently more (or less) sustainable than the current pattern,
but it does allow certain gains to be traded off against other losses.
Pattern of Supply
No. 3 Compared to the Current Pattern (No. 1)
8.11
Pattern of Supply No. 3 is
the pattern which might be expected to emerge if the dredging licences for both
Nash Bank and Helwick Bank were withdrawn, again without any new sand and
gravel quarries being opened in South East Wales, but with two additional
dredging licences being issued, permitting new dredging further offshore in the
Bristol Channel.
8.12
The only differences between
the two Patterns of Supply, as previously summarised in Figure 7.3, are:
(i)
a very sharp reduction in
dredging of sand from close to shore (350,000 tonnes vs 1,122,000 tonnes);
(ii)
a very sharp increase in
dredging of sand from mid-Channel (790,000 tonnes vs 18,000 tonnes).
|
Figure 8.3:
|
'Sustainability Scorecard' for Pattern of Supply
No. 3 compared to Pattern of Supply No. 1 (the current pattern)
|
|
|
|
Clear
|
Increase in stock (short term)
|
|
Most
Sustainable
|
|
|
(3-1) (3-5)
xx
|
Minor
|
(3-6)
x
|
|
|
(3-4) x
|
|
No
|
|
Clear Minor
Increase in rate of use (long term)
|
change
|
Minor Clear
Decrease in rate of use (long term)
|
|
|
|
Minor
|
Decrease in
stock (short term)
|
|
|
|
Least
Sustainable
|
|
Clear
|
|
|
|
|
|
|
|
|
|
|
|
|
NB:
|
Only those items of capital where Pattern of
Supply No. 3 differs from the current pattern are shown.
|
|
Key:
|
(3-N)
|
Pattern of Supply No. 3, item of
capital number N (see below).
|
|
|
N
|
Item of capital
|
|
|
1
2
3
4
5
6
7
8
9
10
11
12
|
Fossil fuels
Soils and non-energy minerals
Fresh water
Seas and oceans
Clean air and healthy
climate
Healthy ecosystems
Human health
Knowledge
Social inclusion
Housing
Means of production
Transport and energy
infrastructure
|
8.13
The full sustainability
assessment of Pattern of Supply No. 3 compared to Pattern of Supply
No. 1 (the current pattern) can be found in Appendix 11. The main elements
of this comparison, and the conclusions which arise from it are as follows.
8.14
As with Pattern of Supply
No. 2, the only sustainability gains from Pattern of Supply No. 3 are
in the marine environment. They involve a possible reduction in damage to
marine ecosystems (a small and uncertain gain), and a much clearer and
important gain in terms of reduced impact on beaches as a result of shifting
dredging further offshore (and, specifically, away from Nash Bank). These gains
are at the cost of a small increase in the rate of use of fossil fuels, and the
environmental damage done as a result of this.
8.15
This is illustrated in Figure
8.3 opposite, which provides a 'sustainability scorecard' for Pattern of Supply
No. 3 compared to the current pattern of supply. The same information is
summarised in Figure 8.4 below, which provides the 'headline findings' from the
full sustainability assessment in Appendix 11.
|
Figure 8.4
|
Predicted differences in
the rates of depletion of items of environmental and human/social capital as
a result of switching from Pattern of Supply No. 1 to Pattern of Supply
No. 3
|
|
Gains
èèè
|
Clear reduction in the rate of
depletion
|
4 - Seas and oceans
|
|
small reduction in the rate of
depletion
|
6 - Healthy ecosystems
|
|
Neutral
|
No change in the rate of depletion
|
2 - Soils and non-energy minerals
3 - Fresh water
7 - Human health
8 - Knowledge
9 - Social inclusion
10 - Housing
11 - Means of production
12 - Transport and energy
infrastructure
|
|
Losses
ççç
|
Clear but very small increase in the
rate of depletion
|
1 - Fossil fuels
5 - Clean air and healthy climate
|
8.16
On balance, Pattern of Supply
No. 3 is inherently more sustainable than the current pattern, offering a
major environmental gain at the expense of relatively small losses.
Pattern of Supply
No. 4 Compared to the Current Pattern (No. 1)
8.17
Pattern of Supply No. 4 is
the pattern which might be expected to emerge if there was an end to the
dredging of sand from both Nash Bank and Helwick Bank, accompanied by a more
permissive attitude towards new sand and gravel (and crushed rock) quarries in
certain parts of South East Wales, and with two additional dredging licences
being issued, permitting new dredging further offshore in the Bristol Channel.
8.18
The main differences between
the two Patterns of Supply, as previously summarised in Figure 7.3, are:
(i)
a very sharp reduction in
dredging of sand from close to shore (350,000 tonnes vs 1,122,000 tonnes);
(ii)
a sharp increase in dredging of
sand from mid-Channel (550,000 tonnes vs 18,000 tonnes).
(iii)
a marginal (2%) reduction in
crushed limestone production;
|
Figure 8.5:
|
'Sustainability Scorecard' for Pattern of Supply
No. 4 compared to Pattern of Supply No. 1 (the current pattern)
|
|
|
|
|
Clear
|
Increase in stock (short term)
|
|
Most
Sustainable
|
|
|
(4-6)
¥
|
(4-3)
¥
|
|
(4-7)
¥
|
Minor
|
|
|
(4-1) (4-2)
¥¥
|
|
|
(4-4) (4-5)
¥¥
|
|
|
|
|
No
|
|
|
Clear Minor
Increase in rate of use (long term)
|
change
|
Minor Clear
Decrease in rate of use (long term)
|
|
|
|
(4-9)
¥
|
|
|
Minor
|
Decrease in
stock (short term)
|
|
|
|
|
Least
Sustainable
|
|
Clear
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
NB:
|
Only those items of capital where Pattern of
Supply No. 4 differs from the current pattern are shown.
|
|
Key:
|
(4-N)
|
Pattern of Supply No. 4, item of capital
number N (see below).
|
|
|
N
|
Item of capital
|
|
|
1
2
3
4
5
6
7
8
9
10
11
12
|
Fossil fuels
Soils and non-energy
minerals
Fresh water
Seas and oceans
Clean air and healthy
climate
Healthy ecosystems
Human health
Knowledge
Social inclusion
Housing
Means of production
Transport and energy
infrastructure
|
(iv)
a large volume of mixed sand
and gravel quarried locally (350,000 tonnes vs nil);
(v)
a complete cessation of imports
of mixed sand and gravel from England (nil vs 100,000 tonnes).
8.19
The full sustainability
assessment of Pattern of Supply No. 4 compared to Pattern of Supply
No. 1 (the current pattern) can be found in Appendix 12. The main elements
of this comparison, and the conclusions which arise from it are as follows.
8.20
Pattern of Supply No. 4
offers several sustainability gains: in the marine environment by moving
dredging further offshore and by reducing the overall 'take' of dredged
aggregate, and by reducing overall energy use and the associated emissions of
greenhouse gases and other pollutants. These gains are, of course, not free:
they come at the cost of a small reduction in direct employment, and some
damage to terrestrial ecosystems and the water environment as a consequence of
land-based quarrying.
8.21
This is illustrated in Figure
8.5 opposite, which provides a 'sustainability scorecard' for Pattern of Supply
No. 4 compared to the current pattern of supply. The same information is
summarised in Figure 8.6 below, which provides the 'headline findings' from the
full sustainability assessment in Appendix 12.
|
Figure 8.6
|
Predicted differences in
the rates of depletion of items of environmental and human/social capital as
a result of switching from Pattern of Supply No. 1 to Pattern of Supply
No. 4
|
|
Gains
èèè
|
Clear reduction in the rate of
depletion
|
4 - Seas and oceans
5 - Clean air and healthy climate
|
|
Clear but small reduction in the rate
of depletion
|
1 - Fossil fuels
2 - Soils and non-energy minerals
|
|
Neutral
|
No (or very little) change in the
rate of depletion
|
8 - Knowledge
10 - Housing
11 - Means of production
12 - Transport and energy
infrastructure
|
|
Losses
ççç
|
Very small increase in the rate of
depletion
|
7 - Human health
|
|
Clear but small increase in the rate
of depletion
|
3 - Fresh water
9(1) - Social inclusion
|
|
Clear increase in the rate of
depletion
|
6 - Healthy ecosystems(2)
|
|
Note:
|
(1)
(2)
|
Together with a minor decrease in the stock of capital as a result of
increased unemployment.
Reducing with time if sites are restored to enhance biodiversity.
|
|
|
|
|
8.22
Whilst Pattern of Supply
No. 4 offers more gains, compared with the current situation, than do
either of the other alternatives, it does so at the expense of some important
losses. Whilst some of these are capable of mitigation, the overall
sustainability balance is less positive than that offered by Pattern of Supply
No. 3.
Conclusions from the
Sustainability Assessment Process
8.23
This section draws together the
results of the three 'comparison pairs' set out above (and in more detail in
Appendices 10-12) in an effort to draw whatever conclusions can reasonably be
drawn about the sustainability implications of the three possible policy
changes.
8.24
All three 'comparison pairs'
yield conclusions about the expected impacts on stocks and flows of 12 items of
environmental and human/social capital. Because the changes under consideration
are policy changes rather than physical developments, the changes in capital
are very limited, certainly when compared to the likely changes in rates of
future use of resources.
8.25
Figure 8.7 sets out the
comparisons, including the baseline case (Pattern of Supply No. 1), which
clearly involves no change from the present position. Figures 8.1, 8.3 and 8.5
present the same information, but in a more visual way, to facilitate
comparisons between the four patterns of supply.
8.26
The main points to be noted
from Figure 8.7 and from a comparison between Figures 8.1, 8.3 and 8.5 are as
follows:
(i)
all gains (i.e. items to the
right of the 'no change' point on the 'sustainability scorecards') are
environmental;
(ii)
in Patterns of Supply
Nos. 2 to 4 there are trade-offs between some environmental gains and a
mixture of environmental and human/social losses;
(iii)
Pattern of Supply No. 2
offers two clear gains but many more minor losses;
(iv)
Pattern of Supply No. 3
offers one major and one minor gain at the expense of fewer (and smaller)
losses;
(v)
Pattern of Supply No. 4
offers more gains than the other two, but also some clear losses, most notably
affecting terrestrial ecosystems.
8.27
The human/social losses (which
affect Patterns of Supply Nos. 2 and 4) are all almost certainly capable
of mitigation. If such mitigation is assumed, then Pattern of Supply No. 2
may present a slight improvement in overall sustainability, compared with the
current situation, and No. 4 becomes an even starker choice (between
savings of natural resources and a reduction in global warming on the credit
side, and potential damage to terrestrial ecology on the other). Overall,
Pattern of Supply No. 3 appears to offer the prospect of a more
sustainable outcome than the others, but the differences are relatively slight
and are influenced by the weighting attached to individual issues.
|
Figure 8.7
|
Predicted
differences in the rates of depletion of items of environmental and
human/social capital between four pattern of aggregate supply
|
|
Items of capital
|
Baseline (Pattern of Supply
No. 1)
|
No. 2 vs No. 1
|
No. 3 vs No. 1
|
No. 4 vs No. 1
|
|
1. Fossil
fuels
|
No change
|
Small increase
|
Very small
increase
|
Small
reduction
|
|
2. Soils and
non-energy minerals
|
No change
|
Clear
reduction
|
No change
|
Small
reduction
|
|
3. Fresh water
|
No change
|
Very little
change
|
No change
|
Small increase
|
|
4. Seas and
oceans
|
No change
|
Clear
reduction
|
Clear
reduction
|
Clear
reduction
|
|
5. Clean air
and healthy climate
|
No change
|
Small increase
|
Very small
increase
|
Clear
reduction
|
|
6. Healthy
ecosystems
|
No change
|
Very little
change
|
Very small
(and uncertain) reduction
|
Clear increase(2)
|
|
7. Human
health
|
No change
|
Probably a
small increase
|
No change
|
Very small
increase
|
|
8. Knowledge
|
No change
|
Very little
change
|
No change
|
Very little
change
|
|
9. Social
inclusion
|
No change
|
Small increase(1)
|
No change
|
Small increase(1)
|
|
10. Housing
|
No change
|
Small increase
|
No change
|
No change
|
|
11. Means of
production
|
No change
|
Very little
change
|
No change
|
No change
|
|
12. Transport
and energy infrastructure
|
No change
|
Small increase
|
No change
|
No change
|
|
Note: (1) Together with a minor decrease in
the stock of capital due to increased unemployment.
(2) Reducing with time if sites are
restored to enhance biodiversity.
|
|
|
|
|
|
|
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Discussion
9.1
Chapter 2 establishes that
aggregates are crucial to society, and describes three main considerations
which were central to the decision to commission this study, namely:
(i)
the continuing uncertainty that
surrounds the long-term effects of dredging for sand in the Bristol Channel, on
which South East Wales has traditionally been highly dependent;
(ii)
a desire to achieve reasonable
long-term security of supply as far as aggregate in South East Wales is
concerned, even if that means considering the exploitation of land-based
sources; and
(iii)
the importance which the
Assembly places on sustainability right across the spectrum of policy issues.
9.2
Chapter 3 explains in more
detail why coastal processes are perceived as such an important issue, and
describes what is meant by sustainability.
9.3
The work which has been done
for this study on coastal processes, and which is summarised in Appendix 5, has
gone some way to resolving the long-standing differences of opinion and
interpretation which had for many years divided the researchers who have
studied the Bristol Channel, and who have attempted to predict the consequences
of dredging for sand.
(i)
an end to the dredging of sand
from Nash Bank, without any sand and gravel quarries being opened in South East
Wales, and without any additional dredging licences being issued for dredging
in the Bristol Channel;
(ii)
an end to the dredging of sand
from both Nash Bank and Helwick Bank, again without any new sand and gravel
quarries being opened in South East Wales, but with two additional dredging
licences being issued, permitting new dredging further offshore in the Bristol
Channel;
(iii)
an end to the dredging of sand
from both Nash Bank and Helwick Bank, but with sand and gravel and crushed rock
quarries being permitted at various locations in South East Wales if required,
and with two additional dredging licences being issued, permitting new dredging
further offshore in the Bristol Channel.
9.5
As is made clear there, these
are not policy prescriptions, but theoretical options designed to highlight the
real choices to be made. The selection of these options does not imply any
judgement on the merits (or otherwise) of the various applications to dredge
sand from the Bristol Channel that are currently being considered by the Assembly.
9.6
Chapters 5-7 provide an
analysis of these three policy scenarios, and an assessment of what they might
mean in practice. It is a fundamental plank of this study that any comparison
between policies (or between aggregate supply options) must be between complete
portfolios of supply, not between pairs of individual elements (such as marine
dredging and quarrying). This is because aggregates vary in their quality and
potential uses, such that varying one element in the equation generally has
knock-on impacts on all (or most) of the other elements. Most obviously,
replacing marine-dredged sand with quarried sand inevitably has knock-on
effects on the pattern of demand for crushed rock, because quarried sand almost
always comes mixed with gravel, which will therefore displace some of the
crushed rock that was formerly blended with marine sand for use in concrete.
9.7
One of the crucial findings
from the analysis reported in Chapters 5-7 and the accompanying Appendices, is
that marine dredged sand is a very high quality material, which makes high
quality concrete with a relatively low input of cement and water. The
manufacture of cement requires very considerable amounts of energy, with the
result that replacing marine sand with alternative materials which have a higher
need for cement, generates a noticeable increase in the emission of greenhouse
gases (mainly carbon dioxide from fuel combustion).
9.8
These considerations, and many
others, fed into the conclusions on the overall sustainability of the different
policy options (and their accompanying patterns of aggregate supply) which are
reported in Chapter 8. These results were obtained using Symonds'
sustainability model (described in Appendix 4). Like all models, this is
intended to be an aid to decision making, not a rigid mould into which every
situation should be forced. It also generates an 'audit trail', in the sense
that any user or interested party can work through the specific questions
answered in response to each proposed change, to see how each individual answer
affects the broader questions about sustainability. This is important since, as
noted in Chapter 8, the differences in overall sustainability are relatively
slight, and are likely to be influenced by the weighting attached to each issue
by different people.
9.9
In particular, the conclusions
from Chapter 8 need to be considered in the light of the findings on coastal
change reported in Appendix 5. The latter are included in the sustainability
assessment itself, but they also merit particular attention, given that
concerns about coastal change were substantially responsible for prompting the
Assembly to commission this piece of research in the first place).
9.10
Therefore, the wider question
is: when both coastal processes and wider sustainability are considered on a
roughly equal basis, how (if at all) does this change the conclusions about
policy choices?
9.11
The evidence on coastal change
(in Appendix 5) suggests that there are indeed links between dredging activity
and coastal processes, and that these are likely, in some cases and
particularly around Nash Bank, to be reflected in future changes to adjacent
beaches if dredging continues. The timescale for these delayed effects is
likely to be measured in decades rather than years, suggesting that the prudent
response would be to seek alternative arrangements to the dredging of sand from
some of these areas.
9.12
What emerged from the wider
review of data from the Bristol Channel was that the cases of Nash and Helwick
Banks are not directly comparable. The evidence from Helwick Bank suggests that
losses from current dredging are replaced from external sources, and that those
sources are not the beaches of the Gower peninsula. The most likely sources of
sediment involved here are extensive sand deposits within Carmarthen Bay and
the sand wave field that includes the Nobel Banks prospecting area.
9.13
As reported in paragraph 9.4 above, the sustainability assessment looked at three
main alternatives to continued dredging, which in the specific context of Nash
Bank can be summarised as:
(i)
an end to all dredging from
Nash with no replacement licences issued;
(ii)
an end to dredging from Nash,
but with the current tonnage of sand replaced by permitting dredging from
further offshore (including Culver Sands); and
(iii)
an end to dredging from Nash,
but with some dredging from further offshore (including Culver Sands) allowed,
together with some land-based quarrying of sand and gravel.
9.14
The conclusion from Appendix 5
is that, rather than simply shifting dredging further offshore (from Nash to
Culver and Helwick to Nobel), it may also be preferable to shift at least some
of the dredging towards the west as well as further offshore. This would favour
amended versions of Patterns of Supply Nos. 3 and 4, with some of the
dredged sand being taken from the Nobel Banks area rather than all from Culver
Sands, an end to dredging from Nash Bank phased in over 5 to 10 years, and
continued dredging (subject to a precautionary approach) at Helwick Bank.
9.15
However, as the description of
current arrangements in Chapter 5 showed, one of the big merits of the current
pattern of supply is that most of the marine-dredged sand used in South East
Wales is landed very close to its point of first use, keeping road transport to
a minimum. Any move to replace sand dredged from Nash/Culver with equivalent
volumes from Helwick/Nobel would either require the dredgers to sail further in
order to discharge their sand at the same ports and wharves as are currently
used, or it would require additional road haulage from Burry Port (and/or
Swansea and/or Briton Ferry) to major markets such as Cardiff and Newport.
9.16
Chapter 6 establishes that,
with the exception of quarried sand and gravel, most of the potential
alternatives to marine-dredged sand have very real practical and environmental
costs attached to them. Secondary materials like china clay sand and crushed
rock sand significantly increase the demand for water and cement in concrete,
and recycled materials offer no effective substitute for sand (as opposed to
coarse aggregate).
9.17
The economic case, also set out
in Chapter 6, argues for gradual rather than sudden change, and there is
nothing in the data on coastal processes to suggest that a managed change
cannot be accommodated, over a period of 5 to 10 years. This is similar to the
time period that would be required to investigate and progress licences to
quarry sand and gravel within South East Wales.
9.18
In general, patterns of supply
that rely on a balance of sources are inherently more stable than those that
rely on a small number of sources. This is particularly true when one of those
sources (i.e. marine dredging) attracts strong hostility from certain segments
of the general public, whatever the basis for that hostility.
9.19
Thus, whilst the sustainability
analysis favours a shift in the location of dredging (Pattern of Supply
No. 3) slightly more than the increased use of alternative (primary and
secondary) land-based materials (Pattern of Supply No. 4), it would be
prudent to investigate and safeguard these alternative materials for future use
and, subject to adequate mitigation of environmental impacts, to develop some
of them now.
9.20
In the case of land-based sand
& gravel, detailed investigations need to be carried out by mineral
operators to assess the technical suitability of potential resources,
especially in areas where ecological and landscape impacts can be minimised. To
encourage this, mineral operators need to be given a clear signal that
technically sound proposals for mineral development in such areas are likely to
be met with a favourable response.
9.21
In the case of secondary
materials (such as china clay sand, crushed rock sand and foundry sand), the
conclusions from this study are that, although they cannot replace
marine-dredged sand without significant adverse implications for
sustainability, they can displace some of it from certain market segments (not
including concrete). They can certainly be used instead of primary aggregates
in many low grade applications (such as bulk fill) and positive steps should be
taken to achieve this.
Conclusions
9.22
The key conclusions from this
study are as follows.
(i)
The policy prescriptions within
MADP are generally prudent, even though the evidence contained in this study
points towards a slightly different interpretation of some of the facts
compared to that which has obtained before.
(ii)
There is evidence of sediment
transport links between offshore sandbanks within some parts of the Bristol
Channel and the beaches of South East Wales. The links are generally weak,
however, and do not imply that dredging will inevitably have impacts on the
beaches. The exception is Nash Bank where it is clear that dredging cannot
continue indefinitely without eventually giving rise to localised impacts on
the adjoining coast. No such impacts have yet been detected, and none are
anticipated in the short to medium term, but it would be prudent to phase out
the current operations here over the next 5 to 10 years.
(iii)
The cases of Nash and Helwick
Banks are not directly comparable. Of the two, Nash Bank is far less resilient,
because of its location in an area of very high rates of potential sediment
transport, and relatively small rates of natural replenishment. Helwick Bank,
by comparison, is located within an area of much greater sediment availability,
where changes can be buffered by the input of sediment from Carmarthen Bay,
without adverse effects on the beaches.
(iv)
Over the last decade, Nash Bank
has been losing volume at a rate that is higher than can be accounted for by
dredging alone, and at current levels of shrinkage could be eliminated
altogether within a period of 90 to 215 years. Long before that point it would
cease to function as an effective breakwater, and impacts would then be felt on
the adjacent shoreline. Alternatives to Nash, as an important source of high
quality fine aggregate, therefore do need to be found.
(v)
Most of the potential
alternatives have very real practical and environmental costs attached to them.
Secondary materials like china clay sand and crushed rock sand significantly
increase the demand for water and cement in concrete (thereby increasing fossil
fuel consumption and emissions of greenhouse gases), and recycled materials
generally offer no effective substitute for sand (as opposed to coarse
aggregate).
(vi)
Good quality land-won sand and
gravel deposits offer far greater potential in all of these respects, but also
have inevitable impacts on landscape, ecology and the water environment (in
particular). These, however, could largely be mitigated, through a combination
of careful location and implementation of best working practices.
(vii)
Irrespective of environmental
considerations, there is no real chance that all of the marine-dredged sand
currently landed in South East Wales could be replaced, (even drawing on all realistic
alternative sources of supply), without raising the cost and reducing the
quality of construction. This would have definite adverse economic consequences
for the region, and would not be justified on sustainability grounds. It would
also result in environmental impacts being exported.
(viii)
Subject to detailed technical
assessments of individual prospects being carried out to prove their quality,
it should, however, be possible to replace a proportion of the marine-dredged
sand by land-won alternatives. Providing that the associated environmental
impacts were adequately mitigated, a partial substitution of marine sand with
land-won alternatives would provide a more sustainable pattern of supply than
that which exists as present.
(ix)
Overall, however, this study
has indicated that the clearest increase in sustainability would be achieved by
a gradual shift of dredging operations from inshore areas (particularly Nash
Bank) to other areas further offshore and/or further west. This conclusion is
subject to the findings of ongoing and future site-specific environmental
assessments at the alternative dredging sites. It would be imprudent,
therefore, to rule out the future need for land based sand and gravel
resources.
(x)
There is a strong economic case
for avoiding precipitate change. Any of the alternative policy scenarios that
have been considered could be phased in over a transition period, and clear
policy statements of intent, tied to a clear timetable, will encourage more
efficient and less disruptive market changes.
Recommendations
9.23
The recommendations that flow
from the above conclusions are as follows.
(i)
Consideration should be given
to amending MADP to steer dredging further west along the Bristol Channel and,
more specifically, to phase out dredging on Nash Bank over a period of 5 to 10
years. This could be achieved by giving notice that, within a minimum of 5 and
a maximum of 10 years, sediment cell CBC1 (which includes Nash Bank) will be
re-classified as a Policy 3 area; and that (more immediately) sediment cell IBC2
(which includes Culver Sands) will be re-classified as a Policy 2 area. Further
independent research on the geomorphology and sediment dynamics of Culver Bank
(not carried out in the present study) might demonstrate that the latter
suggestion is unnecessary, but in the absence of such work, a precautionary
approach is warranted.
(ii)
Other things being equal, and
subject to appropriate consideration of more detailed and ongoing technical
studies, continued dredging on Helwick bank and new dredging proposals for the
Nobel Banks area should be viewed favourably unless and until new evidence is
found of adverse environmental impacts that can reasonably be linked to these
operations.
(iii)
Until such time as it is
modified in the light of unequivocal new evidence, the conceptual model
developed for this study by Pethick & Thompson (2002) should be used by the
Assembly as a context for the evaluation of future dredging applications and
for establishing monitoring requirements to be attached to future licenses. These
requirements should include full, three-dimensional analysis of bathymetric
changes on both licensed areas and adjoining beaches / sand bodies.
(iv)
As noted in MPPW and stated
clearly in the draft Aggregates Technical Advice Note (Aggregates TAN), MPAs
should, as a matter or urgency, safeguard significant areas of potential
land-based sand and gravel resources (as identified in the earlier Symonds
report) until such time as these are either exploited or proved by detailed
investigations to be technically unsuitable.
(v)
In anticipation of the need for
at least some land-won sand and gravel in future years, the Aggregates TAN
should provide mineral operators with a positive signal that well-founded
applications for extraction within appropriate (generally unconstrained)
locations will be given favourable consideration. This could take the form of
‘Provisional Preferred Areas’ as outlined in the earlier Symonds report on
land-based extraction.
(vi)
The Assembly and the South
Wales Regional Aggregate Working Party should establish a mechanism for keeping
future supply options under review. As well as monitoring the effects of marine
dredging, it should monitor the progress of technical investigations of
potential land-based and secondary aggregate resources, to determine the extent
to which these can be relied upon, if and when required. Depending on the
findings of such reviews, future policy options may need to be revised.
(vii)
To the extent that specific
applications can be identified for the use of secondary aggregates such as crushed
rock sand and china clay sand in place of primary aggregates, without giving
rise to greater environmental impacts overall, the Assembly and Local Planning
Authorities should look favourably on any proposals to develop facilities for
the import of such materials into South East Wales by sea or rail.
(viii)
The South Wales Regional
Aggregate Working Party and/or individual MPAs should carry out at least
preliminary desk studies to seek to identify any significant stores of foundry
sand in South East Wales in order to establish whether such a material offers a
realistic alternative to primary aggregate.
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