for europe’s urban sustainability · 16.25 urban dependence on coastal seas – glasgow and the...

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CUSP2014: The Geoscience Context

for Europe’s Urban Sustainability –

Lessons from Glasgow and beyond

29-30 May 2014

Glasgow Science Centre

Early-stage Researchers’ Workshop 29 May

Full-day Conference 30 May

Joint event organised by the Royal Society of Edinburgh (RSE), British Geological

Survey (BGS), the European Cooperation on Science and Technology (COST)

(Sub-Urban) and Glasgow City Council.

Conference Report organised by the British Geological Survey

and the Royal Society of Edinburgh.

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Early-stage Researchers’ Workshop

Programme (CUSP-COST)

13.30 Welcome and Introduction by Chair

Dr. Diarmad Campbell

Chief Geologist, Scotland, BGS

13.35 Glasgow Through the Ice Age

Dr. Andrew Finlayson

Quaternary Geologist, BGS

13.55 Strengths and Weaknesses of Deterministic 3D modelling of Superficial Deposits – Lessons from Glasgow

Dr. Katie Whitbread

Sedimentary Geologist/Geomorphologist, BGS

14.15 Using Stochastic Modelling to Understand Variation in Lithology of

Glacial and Fluvial Deposits in Central Glasgow, UK

Dr. Tim Kearsey

Survey Geologist, BGS

14.35 Management and Access to Subsurface data in Urban Areas: Lessons

learnt from Glasgow and Europe

Helen Bonsor

Hydrogeologist, BGS

14.55 Glasgow Energy from Mine Workings Project: Progress to Date

Emma Church

PhD Research Student, Glasgow Caledonian University

15.15 Heat from Mine Waters: Energy in the Right Place

Dr. Hugh Barron

Responsive Surveys Scotland Manager, BGS

15.35 Tea/Coffee and opportunity to view posters

15.55 The Restoration of Saltmarshes and Their Value as a Coastal Flood Defence

Kate Wade

Sediment Ecology Research Group, St Andrews University

16.15 Human Impact on Sediment Quality in the Clyde Post-Industrial Catchment

Dr. Solveigh Lass-Evans Daphne Jackson Fellow, British Geological Survey

16.35 The Influence of Sediment Characteristics on the Transport of Pathogens from Freshwater to Coast

Adam Wyness PhD Researcher & Post Graduate Representative, The James Hutton Institute

16.55 Closing Remarks

Professor Paul Bishop FRSE Professor of Geography, University of Glasgow

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Conference Programme 08.30 Registration

The Urban Agenda and its Wider Context

08.55 Introduction and Overview

Dr. Diarmad Campbell Chief Geologist, Scotland, BGS

(Dr. Martin Smith, Simon Price)

09.05 Welcome and Conference Opening

Sir Kenneth Calman KCB FRSE FMedSci Chancellor, The University of Glasgow

Session 1: Subsurface Knowledge Exchange in Europe and Beyond

09.15 Introduction by Chair

Dr. Michiel van der Meulen Chief Geologist, Research Manager Geomodelling, TNO/Geological Survey of the

Netherlands

09.20 Urban Planners and the Subsurface: Out of Sight, Out of Mind

Ignace Van Campenhout Municipality of Rotterdam

09.40 ASK Knowledge Exchange Network for Glasgow and Beyond

Helen Bonsor Hydrogeologist, BGS

(Hugh Barron1, Jonathan Lowndes1, Garry Baker1, David Hay2, Simon Watson3, Donald Linn2, Iain Hall4, Ken Lawrie1 1BGS; 2Glasgow City Council; 3Hunterian Museum; 4Grontmij)

09.55 BRO National Key Register of the Netherlands

Dr. Michiel van der Meulen Chief Geologist, Research Manager Geomodelling, TNO/Geological Survey of the

Netherlands

10.10 COST Action TU1206 Sub-Urban: A European Network to Improve

Understanding and Use of the Ground Beneath our Cities

Hans deBeer Vice-chair, COST TU1206; Team Leader, Groundwater and Urban Geology,

Geological Survey of Norway

(Dr. Diarmad Campbell, BGS)

10.30 Tea/Coffee and Opportunity to view Posters

Session 2: Urban Subsurface 3D Property Modelling


Dr. Diarmad Campbell, BGS

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11.10 National to Urban Scales of Subsurface Modelling in the Netherlands

Dr. Jeroen Schokker Geologist/Geomodeller, TNO/Geological Survey of the Netherlands

11.30 How to Present a Can of Worms: Capturing the Complexity of Glasgow’s Superficial

Deposits

Dr. Katie Whitbread Sedimentary Geologist/Geomorphologist, BGS

(Sarah Arkley, Dr. Andrew Finlayson, BGS)

11.45 Big Faults, Little Faults: Multi-scalar Bedrock Modelling in the Clyde Catchment

Dr. Alison Monaghan Geologist, BGS

(Mike McCormac, Dr. Dave Millward, Dr. Tim Kearsey, Bill McLean, Tony Irving, BGS)

12.00 Stochastic Modelling of Glasgow’s Superficial Geology

Andrew Kingdon Petrophysicist and Team Leader Parameterisation and Statistics, BGS

(John Williams, Paul Williamson, Dr. Murray Lark, Dr. Tim Kearsey, Andrew Finlayson, Marcus Dobbs, BGS)

12.15 Geotechnical GIS of Glasgow

David Entwisle Senior Engineering Geologist, BGS

(Suzanne Self, BGS)

12.30 Lunch

Session 3: Urban Geochemistry and its Wider Context (soil, sediment and

surface water quality)


Fiona Fordyce Senior Environmental Geochemist, BGS

13.35 Geochemical Baseline Surveys of Glasgow and the Clyde Basin: Overview and Soils

Fiona Fordyce, BGS

(Paul Everett1, Dr. Jenny Bearcock2, Bob Lister2

BGS Edinburgh1, BGS Keyworth2)

13.50 Mapping the Water Chemistry of the Clyde Basin Drainage Network: Regional Context

and the Urban Imprint

Dr. Jenny Bearcock

Hydrogeochemist, BGS

(Dr. Pauline Smedley2, Paul Everett1, Louise Ander2, Fiona Fordyce1 BGS, Edinburgh1, BGS Keyworth2)

14.05 Soil Quality and Health/Deprivation Indicators in Glasgow

Professor Marian Scott OBE FRSE Professor of Environmental Statistics, School of Mathematics and

Statistics, University of Glasgow

(Stephen Morrison1 Fiona Fordyce2 National Australia Bank1, BGS2)

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14.20 Chemical Speciation and Bioaccessibility of Chromium in Contaminated Glasgow

Soils

Professor John Farmer Professor Emeritus and Senior Honorary Professorial Fellow, University of Edinburgh

(Andrew Broadway1, Fiona Fordyce2

Environmental Resources Management (ERM) 1, BGS2)

14.35 Anthropogenic and Natural Geochemical Factors on Urban Soil Quality

Professor Andrew Hursthouse FRSC Professor of Environmental Geochemistry, University of the West of Scotland

14.50 Q&A

15.00 Tea/coffee and Opportunity to view Posters

Session 4: Urban Groundwater, Estuary and Marine


Brighid Ó Dochartaigh

Senior Hydrogeologist, BGS

15.35 Groundwater Modelling and Monitoring in Hamburg

Paul Meyer Hydrogeologist, Groundwater Modeller, CONSULAQUA Hamburg

and Lothar Moosmann Hydrogeologist, Ministry of Urban Development and Environment of

Hamburg (BSU) – Geological Survey

15.55 Urban Groundwater: A Pilot Monitoring Network for Glasgow

Stephanie Bricker Hydrogeologist, BGS

(Brighid Ó Dochartaigh, Helen Bonsor, BGS)

16.10 Groundwater Modelling to Improve Conceptual Understanding of Flow under Glasgow

Dr. Majdi Mansour Senior Groundwater Modeller, BGS

(Brighid Ó Dochartaigh, Dr. Rachel Dearden, Ryan Turner, Dr. Andrew Hughes, BGS)

16.25 Urban Dependence on Coastal Seas – Glasgow and the Firth of Clyde

Professor Michael Heath Professor of Fisheries Science, University of Strathclyde

16.40 Estuary and Marine Contamination in the Clyde Catchment

Dr. David Jones Project leader/Geochemist, BGS

17.00 CUSP: The Global Dimension

Dr. Martin Smith, BGS

Science Director, BGS Global

(Dr. Diarmad Campbell, BGS)

17.15 Closing Remarks

Professor John Coggins OBE FRSE Former Vice-Principal for Life Sciences and Medicine, University of Glasgow

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Foreword

Glasgow, Scotland’s largest city, is built along the upper Clyde estuary and lower River Clyde. In the heart of the city are the Clyde Gateway and Clyde Waterfront areas – a national urban regeneration priority for Scotland. This regeneration is intended to stimulate economic growth, drive smaller community projects, and tackle concentrated deprivation resulting from industrial decline. To underpin this regeneration, the British Geological Survey (BGS) has been developing integrated and attributed dynamic shallow-earth 3D models and other geoscience datasets and knowledge, in partnership with Glasgow City Council and other organisations. This transdisciplinary project – the Clyde-Urban Super-Project (CUSP) – aims to make geoscience information more accessible, relevant and understandable to the wide range of users involved in the sustainable regeneration and development of Glasgow. This conference showcases CUSP, its knowledge exchange (ASK and GSPEC) and its relevance to sustainable use of the urban subsurface, which is being promoted by the related European COST Action-Sub-Urban, whose partners from across Europe will illustrate their work.

Early-stage Researchers’ Workshop Programme (CUSP-COST)

13.30 Welcome and Introduction

CUSP project leader, Dr. Diarmad Campbell, welcomed guests and gave an overview of the project. The transdisciplinary CUSP project, now in its fifth year, is working in partnership with Glasgow City Council and a range of universities within the UK and further afield. The focus of CUSP is on Glasgow and the River Clyde which flows through the city. The CUSP project looks at a range of aspects within the Clyde catchment and inner estuary, from subsurface to ground water properties and the applications of knowledge from such studies.

Dr. Campbell also pointed out that papers from many of the presentations from this conference will be included in a forthcoming Royal Society of Edinburgh thematic volume.

13.35 Dr. Andrew Finlayson, Quaternary Geologist, BGS

Glasgow through the Ice Age

Dr. Finlayson opened his talk with an introduction of the natural processes that have shaped the subsurface of the Clyde Catchment. The landscape of Glasgow has been shaped by climate change and geological processes during the last ice age, a time when large ice sheets advanced and retreated in the Northern Hemisphere. Evidence for this comes from the study of ice core records, which have preserved a record of the planet’s climate oscillating between warm and cold conditions. The climate ‘wobbles’ like this due to large scale events occurring across the planet, such as tectonic plate movements which cause mountain uplift, shifts in the geographical position of land masses, and the opening and closing of sea ways. An example of the latter was given by Dr. Finlayson as the opening of the sea way between North and South America, which caused changes in salinity and the North Atlantic current, which in turn had influence on the planet’s climate as it affected air current circulation and heat transfer around the planet. As well as the climate being influenced by terrestrial processes, Earth is particularly sensitive to solar processes such as orbital variations: eccentricity (moving between a circular to elliptical orbit around the Sun), obliquity (changes in angle of Earth’s axis of rotation) and precession (Earth’s wobble on its axis – akin to the wobble seen on a spinning top). In the first half of the 20th century, the Serbian geophysicist, Milutin Milanković built on earlier work from the Scottish scientist James Croll to explain the effect these solar processes have on Earth’s climate, and deduced that Earth should go into glaciation around every 100,000 years, a theory proven through the study of ocean cores and ice cores.

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The extent of the last glaciation in Scotland has been explored using an Olex bathymetric set from echo sounder data, captured by hundreds of fishing boats and research vessels sailing in British waters. Dr. Finlayson presented an image showing this bathymetric data, which revealed a fascinating sub-ocean landscape. The image showed arcuate features, glacial moraines, on the western part of the continental shelf confirming that the last ice sheet reached the continental shelf at least. Other features were also visible, such as channels scoured out of the sea bed which represent tunnel valleys, formed underneath the ice sheet through high pressure processes.

By combining geological information from sources such as bathymetric data, ice cores, and computer modelling, simulations of the ice sheet over Scotland during the last ice age have been achieved. In a video presented to delegates, a computer model devised by Alun Hubbard of Aberystwyth University showed that at 35 thousand years ago, an ice sheet expanded out of the Highlands and into the Clyde Basin. The ice sheet then retreated until a brief readvance 12,000 years ago during the Loch Lomond Glacial Readvance, before collapsing. From fossils found throughout Bishopbriggs and the Ayrshire basin, scientists know that prior to ice sheet growth, Glasgow would have been populated by woolly rhinos, woolly mammoths, reindeer and tundra vegetation. However, when ice began spilling through the Vale of Leven sourced from the Scottish Highlands 35,000 years ago, Glasgow would have been covered by at least 1km of ice. The weight of the ice pushed the land down, and therefore during glacial retreat, the sea flooded up to 40m higher than present day sea level. Both west and central Glasgow would have been underwater – Loch Lomond would have been a sea loch, and the remaining ice masses would have been retreating and calving out into the Firth of Clyde.

Glacial deposits left behind by the ice sheet in Glasgow consist mostly of glacial till (accounts for 70% of total sediment within the Clyde Basin) which is composed of a silty sandy clay, firm to stiff, and containing gravel and boulders. Glacial rivers deposited sand and gravel, which consist of 11% of sediment within the Clyde Basin. Sediment thickness maps of the Clyde Catchment show that in the east of Glasgow, these glacial deposits may reach up to 30m thick. In addition to glacial deposits, raised marine and estuarine deposits composed of silts and clays are mostly concentrated within the lower regions of the Clyde Basin, and make up ~13% of the sediment within the Clyde Basin.

In terms of Glasgow’s future climate, we currently live in a full interglacial period and assuming no global warming, this would be expected to end in the next 1500 years or so. However, taking into account the rate of global warming today, it is more likely that the next glacial period will be delayed by up to 500,000 years. Global warming therefore poses an alternative climate consideration, with UK climate projections suggesting a 7 – 54 cm sea level rise in Scotland by 2095, and an IPCC report suggesting that global mean sea level will rise by 103 m by the year 2300.

Dr. Finlayson concludes that past climate and glacial processes are responsible for much of the material that Glasgow is built upon, and that the present day climate is a result of a balance between factors of orbital facing, atmospheric composition and global ice volume. In the long term, the current day climate is unlikely to remain constant.

13.55 Dr. Katie Whitbread, Sedimentary Geologist/Geomorphologist, BGS

Strengths and weaknesses of deterministic 3D modelling of superficial deposits - lessons from Glasgow

In this presentation, Dr. Whitbread explores how British Geological Survey (BGS) geologists have evolved from modeling geology from a conceptual approach, where the geologist produces models based on their own interpretations and sketches, to deterministic processes, to model the subsurface on the basis of numerical algorithms. 3D models are becoming increasingly important and sought after by users of the subsurface, such as urban

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planners, decision makers and contractors. 2D geological maps provide a plan view of the geology sitting immediately at the surface, but cannot be interrogated to provide information of what lies beneath the geology that sits at the surface. As with most geological materials, superficial deposits (glacial, marine, fluvial, estuarine, etc.) often have complex morphologies, and as such there is a pressing need to create 3D models of superficial deposits within the subsurface to help us understand and characterize them, to inform us on how to manage our environment.

BGS have moved from a conceptual model based approach to a deterministic 3D modelling approach, which exists somewhere between conceptual and computational approaches. BGS build 3D models using their in-house GSI3D modelling software, which has been developed side by side with BGS geologists’ modelling needs. In a deterministic 3D model, the geologist takes borehole data along with lithological information (e.g. from a 2D map), and codes it up into packages of deposits, and correlates these into cross-sections. Incorporation of borehole data allows construction of multiple cross-sections with multiple orientations, leading to the development of a network of fence diagrams. Using a deterministic approach, interpolation of surfaces between these fence diagrams can be constructed within GSI3D.

The main advantage of such a deterministic approach is that this method allows for integration of multiple data inputs. For example, over 40,000 boreholes for the Glasgow area exist within the BGS database, and seismic and geophysical data can also be integrated into the modelling approach. Dr. Whitbread describes another strength of the deterministic approach as it being a good way of dealing with complex deposits. Glasgow’s superficial deposits are indeed complex, and this complexity is something which must be reflected in the models created by BGS. To tackle this, in Glasgow, BGS geologists have broken down the superficial packages into 27 main units, based on lithostratigraphy. This lithostratigraphy grouping is based on a combination of things, such as the order in which the strata spatially occur, and the environment in which they were formed. The power of using lithostratigraphic models is that it provides us with rules by which we can model the characteristics of models, and how they relate to one another. This workflow is currently difficult to do with computational methods. An additional strength of the approach is that deterministic modelling can be used to build versatile and useful models, at a range of scales. The BGS have built a catchment scale model of the Clyde Basin, which allowed them to build a high resolution model of urbanized parts of Glasgow. These high resolution models can now be interrogated for a range of applications, such as looking at the thicknesses of particular units within certain parts of Glasgow, and also for looking at the effects of groundwater processes and flow. It is also useful for outputting useful surfaces, such as the depth to rockhead.

However, there are limitations to the deterministic approach. It is a labour intensive process, taking a total of ten years to develop the Glasgow superficial 3D model. In addition, lithology varies within stratigraphic units, and therefore requires simplifying down to a manageable level for modelling. BGS are developing stochastic models in areas with high borehole density to counter this limitation, and this is discussed in the next presentation. An important limitation that the BGS are working on is how to quantify uncertainty within our models – i.e. how do we know how well our model is representing the subsurface environment? The accuracy of the models relate directly to how much data is available, and BGS can therefore provide a rough indication of the likelihood of accuracy e.g. the models have a higher confidence where there are more boreholes. However, this in turn has limitations, as even in areas with a lot of boreholes there can still be high geological complexity. Dr. Whitbread explained that it is possible to identify where these complex areas are within the model, but reminded us it is difficult to be quantitative about probabilities. The BGS are looking at how to address this, and how to derive a more rigorous approach.

In conclusion, deterministic models can be time consuming to build and maintain, and are difficult to assess for their predictive capability. However, the approach is also versatile,

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capable of being applied at a range of scales, and is good for developing geological understanding.

14.15 Dr. Tim Kearsey, Survey Geologist, BGS

Using stochastic modelling to understand variation in lithology of glacial and fluvial deposits in central Glasgow, UK

This presentation builds on some of the limitations discussed regarding deterministic 3D modelling in the last talk. The BGS 3D model of Glasgow was built using stratigraphical information, which is a good way of understanding the geology but presents a problem if the model interest is in lithology. For example, the Gourock Sand Member in Glasgow is not composed solely of sand; it is described as sand, silt, clay and locally gravel. Therefore, describing how the lithology varies within a 3D model is a problem.

For the Glasgow model, BGS used 4391 geotechnical boreholes to investigate the lithological variations within units such as the Gourock Sand Member. As expected, BGS found that none of the stratigraphic units contained a single lithology, as suggested by their name (e.g. the Law Sand and Gravel Member is composed of a mixture of soft clay, organic material, stiff clay, diamicton and sand and gravel).

Dr. Kearsey discussed the difficulties in correlating such complex units between boreholes for the purposes of model building. To account for complexity, the oil and gas industry build facies models using stochastic modelling, a technique the BGS are researching and starting to use within their models. Stratigraphic models don’t show variability within geological units, and as such, the model implies everything within that one unit is the same lithology. If there are differing components with that layer, how do we represent that? As the BGS have been using boreholes to understand how lithology varies within a particular unit, they have been applying stochastic techniques and using statistics to model two units feathering into one another within a new stochastic lithological 3D model.

Talking the delegates through the procedures used to employ such a method, Dr. Kearsey explained that the BGS model was built by using boreholes and building grids, and developing a sequence stratigraphy approach (i.e. looking at erosional surfaces as a basis for the model). Stochastic modelling then allows simulations to run throughout the gridded model, starting at a difference square within the model each time, and therefore generating a slightly different model during each run. Taking the stratigraphic and results from the lithological (stochastic) model, Dr. Kearsey found that a lot more clay is present at the surface of Glasgow than what is provided in the simpler stratigraphic model. Taking the Paisley Clay Member as an example, it forms a geological unit across Glasgow but there are also a lot more clays distributed between different members, an observation which would have otherwise not been picked up in the stratigraphic model.

As in the previous talk, Dr. Kearsey acknowledged the challenge of predicting the accuracy of stochastic modelling. As an example, two boreholes within Glasgow were used to inform the stratigraphy, but had not been carried through in the stochastic modelling, and so BGS were able to use these as blind tests and see what would be predicted in these boreholes from the model. The results showed that in the upper 10m of the borehole, predictions of lithology were good, close to what was there when drilled. Deeper down in the borehole, over 10m, the ability to predict decreased, and underrepresented the amount of clay. However, it is likely that this is a function of the depth distribution of boreholes used for the remainder of the model, as most boreholes used for the model were less than 10m deep. Dr. Kearsey then showed how BGS illustrated the uncertainty associated with this method, showing delegates a map of the probability of sand units occurring, with a more certain value placed on the location of boreholes, and less certain where there was no subsurface information.

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In conclusion, stratigraphic units consist of multiple lithologies despite their official name. Stochastic modelling allows a model of lithology as well as stratigraphy to be built, and probability maps of different lithologies can indicate uncertainty in data (dependent on borehole data).

14.35 Helen Bonsor, Hydrogeologist, BGS

Management and access to subsurface data in urban areas: lessons learnt from Glasgow and Europe

To understand the subsurface, good quality data sets and access to them are essential. A need for understanding subsurface data management and how it varies through European cities stemmed from a groundwater pilot in Glasgow, where it was difficult to access and reuse large amounts of existing groundwater data for Glasgow. It became clear that if BGS were to provide meaningful models, a way in which to access the wealth of data available in Glasgow was essential. There is an increasing need for all cities, regardless of their starting points or data backgrounds, to maximize past investments in data. This is in order to reduce uncertainty of subsurface ground conditions for effective and sustainable development of urban areas, by developing high quality datasets and data acquisition and by systemizing existing data to match current needs.

Ms. Bonsor describes her work in the COST program, where she participated in knowledge exchange activities with Glasgow, Hamburg and Odense as part of a short term scientific mission between institutions. Hamburg has set a benchmark example in subsurface data management. It has a lot of historic data, and data is still being gathered today. Their data is high quality, easy to use and access, and key systematic data sets inform government and policy level. But what makes this a good example? Hamburg developed strong legislative drivers for data submission to their geological survey, where data is provided in a consistent format to make it easier for the geological survey to understand and use. As a result, stratigraphy matches across different types of model leading to greater efficiency in informing policy. Data is also used consistently by different departments and agreed conceptual models are used to support decision making. Inter-organisation relationships are also important, and significant investment over many years has enabled this collection of comprehensive datasets for the city. The datasets combine what the geological survey are monitoring and capturing, as well as that from private companies. This therefore creates a virtuous cycle of data and knowledge exchange, and allows decisions to be made from the same data and 3D models across different organisations to develop a unified model.

Glasgow provides a different example – it has much less historical data and lower levels of data acquisition compared to Hamburg. Glasgow does have a lot of boreholes, but a lot of that data has too high an uncertainty associated with it, and it is known that there is more data out there than is recorded at BGS. In addition, the data reported to Glasgow City Council is not systematic – it comes in a range of forms, from hand drawn logs, excel to pdf format, and it is therefore very time consuming to access that data, and as a result, is not used. To combat this, BGS have been working to set up the ASK network, a knowledge exchange network, to combine a range of private and government contractors to have virtual data and knowledge exchange. ASK follows best practice as observed in Hamburg, and is moving toward an efficient raw data capture. This has been realized by using a central NERC/BGS data repository – a free flow of data and delivery of updated models. It is also moving toward a standardized report format called GSPEC, using existing industry standards, which can be uploaded via a portal on the BGS website where it is stored for re- access by members of the ASK network.

Odense is a combination of Glasgow and Hamburg – it has significant historical and groundwater data but no legislation for ground investigation data. However a wealth of un-accessed ground investigation data is held in the private sector, which regard it as the ‘family silver’, and as a result there is now insufficient data accessible to the government for major

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urban redevelopment projects. The data is accessible but at a high cost, and as such, high costs and limited data restrict 3D modelling.

Lessons learned from the knowledge exchange activities between institutes highlight that data portals make data highly accessible, and a high awareness of data will inform planning decision making and policy. Having a centralized repository is essential as well as having standardized data. Merging private and public sector data is highly valuable and cost effective. Strong inter-organisational relationships are essential, and develop largely due to collaboration and interest of key individuals within organisations, and should be something that all COST cities aspire to.

To conclude, the COST series of knowledge exchange events between Glasgow, Hamburg and Odense highlighted the full potential of subsurface data, if it is accessible. The knowledge exchange also allowed an assessment of best practice, and gave reassurance that pilot projects in other urban areas, such as Glasgow, is following best practice which we might otherwise not have known.

14.55 Emma Church, PhD Research Student, Glasgow Caledonian University

Glasgow energy from mine workings project: progress to date

The Scottish Government has set a target for renewable heat to account for 11% of Scottish energy consumption by 2020. In 2012, this value was at 4.1%, of which ground source heat pumps (GSHP) account for a small amount. There is a potential for greater energy contribution from GSHP as there is a greater public confidence surrounding them - the public understand extracting heat from mine waters, but there are little incentives available to fund such a project when the technology is not widely known or studied.

Glasgow has its own example of extracting heat from mine waters in the east of the city, in a housing development of 16 houses, which are heated using heat from old mine workings. This scheme was completed 13 years ago, and Ms. Church explained that her PhD research would like to see similar schemes replicated in the future for Glasgow, by developing a planning tool which would allow decision makers to see where best to put our developments using geothermal energy.

The research looks to increase confidence in GSHP technology, and to allow the development of a decision making tool. The initial work for developing this focusses on two urban regeneration areas in the Clyde Gateway – the districts of Dalmarnock and Shawfield. Initial work digitized mine plans from the Coal Authority, which have been used to highlight mine workings within the upper most coal seams in these districts of Glasgow. The next steps in the mapping will be to expand this to cover the whole of the Clyde Gateway and to estimate how much energy can be extracted from such workings, and to inform commercial and domestic users on this low grade heat source. As the mine workings are in bedrock, and mostly within coal mines, only a few of the mines have been modelled in 3D. As BGS hold a comprehensive collection of mine plan information, they have provided mine working data to help with this presentation’s research.

Implementing such a heat source may be of more benefit to new developments, such as offices and regeneration of domestic properties. These developments will be more energy efficient as they are newer buildings, and so would benefit from a local geothermal heat source. Combined with GIS files for mine workings in the urban regeneration areas in the Clyde Gateway, additional GIS layers (such as those looking at where incentives are available for higher fuel poverty areas) may also be of benefit to help decision makers with where to focus development of geothermal heat from mine workings. Currently, mine water temperature and chemical data is sparse, although if more data becomes available this could also be used to display within a GIS package and be easy to understand for non-specialists.

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In Glasgow, there is little information available on mine water properties. Ms. Church described access was available to a few boreholes within the Clyde Gateway, and where water was monitored over a 2 month period. The mine water remained stable at 10°C throughout a cold November period, and in a borehole elsewhere, temperatures reach 13°C. Water samples were also taken from Newmains and SE Glasgow boreholes, and tested for copper, cadmium, chromium, iron, manganese, nickel and zinc. All but iron were detected in trace amounts, whereas iron was present at 16mg/L, which is not thought to present significant problems. However, it is acknowledged that local knowledge of how these systems differ are very important, as depending on the chemistry, there may be a need to restrict oxygen access to mine workings in case the iron turns ferrous.

To conclude, the map and associated information being developed as part of this PhD has great potential to be used as a useful planning tool. It is not intended to replace site investigation and water tests, but rather can be used as a guide as to where to put resources, based on mine working locations, areas of urban regeneration, redevelopment, and fuel poverty districts.

15.15 Hugh Barron, Responsive Surveys Scotland Manager, BGS

Heat from mine waters: energy in the right place

Over 50% of total energy consumption in the UK is from non-electrical heat demand. The Scottish Government climate change targets outline that delivery of 11% of this demand should be sourced from renewable sources by 2020. To achieve this target, the Scottish Government has commissioned a study on the potential for geothermal energy in Scotland, including sourcing heat from mine workings in Scotland. A joint study between AECOM and BGS found that a demonstration/valuation project to showcase the potential of the use of mine water for geothermal heat should be installed as soon as possible in Scotland, as there is a lack of confidence in this relatively unknown (at least, in Scotland) technology. In conjunction with AECOM, BGS suggested two areas in Scotland that could act best as a demonstrator project: Shawfair, near Edinburgh, and the Clyde Gateway in the east end of Glasgow.

Why are mine waters an attractive renewable energy source? They are sourced within old mine workings, and therefore have enhanced recovery potential from groundwater directly, and/or ground source heat pumps (GSHP) can be used to extract heat from them. The mine workings create fluid pathways through low permeability rocks, with abandoned roadways and shafts allowing connectivity between different levels of mine workings. As several mines today are pumped to remove rising groundwater, this water could be used for geothermal heat rather than actually drilling boreholes to access the water. However, due to the industrial revolution, the groundwater may be contaminated and contain excess iron. There are also engineering challenges to be considered in the future, such as how to drill into mine waters, and knowing how long the water will be likely to last once it is pumped.

Disused mines have been utilized elsewhere in the world, such as in Heerland, Netherlands, and there are also smaller examples in Slovenia and Poland. In Scotland, there are two local examples: Shettleston in Glasgow and Lumphinnans in Fife. Taking the former as an example, there are 16 houses heated from groundwater from the underlying mine workings. The annual bill for residents is £150 in heating costs, with a £10 monthly maintenance cost – this is compared to an average of £1000 spent on heating in Scotland per year. However, favourable conditions need to exist to make use of such a resource, including finding suitable sites, matching supply and demand, etc. At the Heerland site in the Netherlands, an open loop system exists where mine water is extracted from 700 m depth and water is re-injected, providing a peak output of 2.2MW – enough to heat hundreds of houses, offices, and shops.

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Going back to Glasgow, extensive mining has been carried out historically, particularly in the east of the city. Since 1872, there has been a legal requirement for the recording of mine abandonment plans, and BGS hold related mining records from 1839 onward. The earlier mines were worked using the pillar and stall method, whereas later mining techniques used the short/long wall technique, which allowed walls to collapse after mining. This method reduced the voids left by mining by 90%, but fractures remain between and above seams, due to subsidence of overlying strata into the voids. The void spaces are predictable, and with the help of mine plans, accessible. Even if filled with collapsed material, the voids have an increased permeability due to flow pathways between blocks of rock. In terms of thermal potential in Glasgow, most of the mines in Glasgow were worked to depths of 300 - 400m, and it has been calculated that 600 km3 constitutes the volume of mines worked in Scotland, in an area of 3800 km3.

There are two key parameters to consider for extraction of heat from mine waters – flow rate and temperature. In boreholes that the BGS have looked at in central Scotland, 5 to 150 litres a second of flow rate has been recorded. Heat extraction at 5 – 25 litres a second is deemed a good rate, and a preferred temperature range is somewhere between 12° and 37°C. For example, in Monktonhall, near Edinburgh, the mine workings are over 900m depth, and have groundwater temperatures of up to 37°C. Shallower mine workings typically have temperatures of 12° - 13°C.

Scotland’s heat demand come 2020 will be 60.1TW, and will require an installed capacity of 33-40MW. Mine waters in Scotland are estimated to potentially provide 12GW of Scotland’s heat demand in favourable conditions – however, the heat cannot be transported far from the area it was sourced, and only a proportion of the mine workings will be suitable for heat extraction, and the heat delivered by GSHP are only efficient for new buildings.

15.55 Kate Wade, 3rd year PhD Student, Sediment Ecology Research Group, St Andrews University

The Restoration of Saltmarshes and Their Value as a Coastal Flood Defence

Saltmarshes are important and valuable habitats, which, over the past 50 years, have been declining at a rate of 100 acres a year due to land being reclaimed for agriculture. Contributing factors also include pollution, climate change, sea level change and storms. Most of the saltmarshes in Scotland are quite small, but still valuable in terms of the ecosystem and what they provide. Coastal erosion protection and coastal flooding defence is an important ecosystem service from saltmarshes. In the UK alone, 26,000 homes and businesses are at risk from coastal flooding, and this number is predicted to grow due to sea level rise and extreme weather events. Urbanised areas are within risk areas for flooding, for example, parts of Glasgow along the Firth of Clyde.

There are two types of flood defence type: natural/soft defences (e.g. sand dunes and salt marshes) and manmade defences (e.g. concrete sea walls). Coastal planners have to take into account if an area is in need of instant protection, and what it is that needs to be protected. Decisions are not simple - manmade defences are a relatively rapid means of providing flood defence, but come at a high cost of £5000/m of wall. Saltmarshes on the other hand take a while to build up, but once in place are sustainable as a natural flood defence. They attenuate waves, accrete sediment (trapping it as the tide comes in and therefore raising its level). If a natural flood defence such as a saltmarsh is used in conjunction with a manmade defence, this lowers the cost significantly of a new sea wall (£400/m of wall) and combines the security of a hard wall whilst maintaining the natural value of an area.

To help saltmarshes regain their habitat, original sea walls are being breached to allow saltmarshes to flood back through and migrate inland, a process currently being inhibited due to rising sea levels. New sea walls are built further inland, allowing substantial new salt

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marshes to form, to help tackle flooding, for example, as at Abbotts Hall Farm in Essex.

Saltmarshes can also be restored through transplantation, i.e. digging up plugs of natural saltmarsh from a donor site, splitting the plugs into sprigs, and transporting to a new site for planting where they will then hopefully develop into a salt marsh. However, is this method of restoration successful? Does it do the same job as a well-established salt marsh? This research looks at saltmarshes in estuaries and how long it takes ecosystems to be restored, and how effectively this is achieved. The study area (the Eden Estuary near St Andrews) was historically fringed by saltmarsh, but 50ha of it has been lost over the last 20 years. Since 2003, monitoring of natural and restored sites within the estuary has been carried out to compare a range of factors including sediment accretion, wave attenuation and sediment stability, amongst others in order to understand the function of salt marshes.

The results showed that sediment accretion is comparable between natural saltmarshes and restored salt marshes after four years from planting, and that they trapped more sediment than mud flats. After 10 years, the plant height in the restored salt marsh is comparable to that of a natural site, and therefore ten years after planting the restored site is able to have the same wave attenuation effect as a natural site. It was shown that sediment stability is not significantly different between sites, and that biofilms play an important role in sediment stability.

In conclusion, saltmarshes are a valuable ecosystem, particularly for coastal defence measures. Restoring saltmarshes is possible but it is important to look at restoration as a whole picture, and to monitor them through time to see if they do the job expected of a natural, well-established salt marsh. The results from this study are useful for managers to understand how natural flood defences can be restored and on what timescales – sediment accretion takes approximately 4 years to stabilize to natural saltmarsh levels, whereas wave attenuation is ~10 years. The effect of sediment stability is complicated, and requires more research.

16.15 Dr. Solveigh Lass-Evans, Daphne Jackson Fellow, BGS

Human Impact on Sediment Quality in the Clyde Post-Industrial Catchment

In the past, Glasgow was a leading centre of industry. It was particularly famous for its ship building, as well as mining, chemical works, engineering and ceramic manufacturing. This study looks at the lasting effect of this industrial heritage on the environment of Glasgow and the surrounding Clyde catchment. Glasgow’s industrial past has left with it a legacy of pollution – to understand this effect on sediment quality within the Clyde, BGS collected samples from stream sediments in the River Clyde in collaboration with Glasgow City Council in 2003, and also in the Clyde estuary with SEPA and Glasgow City Council as part of the BGS Geochemical Baseline Survey of the Environment Project (G-BASE).

The aim of this study is to integrate and interpret data sets to identify the spatial distribution of sediment element concentrations and assess the sediment quality with respect to sediment quality guidelines. Rural stream sediments were sampled at 1 sample per 1.5 km2, and urban stream sediments were collected at 1 sample per 1km2, whilst estuary sediments were sampled via the grab and core method.

The results enabled the creation of element distribution maps across the Clyde catchment, which Dr. Lass-Evans presented to the delegates. Firstly, the concentration of copper within sediments was highlighted, showing a strong influence on urban areas with high concentrations in Glasgow and out into the Clyde estuary. There were relatively low concentrations of copper on ground overlying igneous rocks (such as in the Renfrew Hills), as well as those over-lying Silurian and Devonian rocks in the south of the Clyde catchment area. It was also found that there was a high concentration of copper in the Lead Hills area, due to its historical lead mining past. Moving onto lead distribution, there was also a high

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concentration in the urban areas along the Clyde, as well as again in the Lead Hills area. There was also a high concentration of Pb in the Carboniferous flood basalts of the region. When comparing these results with sediment quality guidelines, it was found that the Clyde catchment exceeded the sediment quality guidelines of Cu, and with Pb, nearly all samples exceeded the quality guideline of 128mg/kg in Glasgow.

To assess the human impact on sediment quality, metals with an anthropogenic origin must be distinguished from naturally occurring metals. To model this, integration of datasets including stream sediment chemistry, mineralization occurrences and mining locations, urban areas, bedrock geology and stream sub-catchment boundaries were taken into consideration. The catchment signature was defined by calculating the average element concentrations from all stream sediments lying within sub-catchment boundaries. Modelling the geological background was more complicated, and the approach taken was to exclude stream sediment that was within urban areas and/or close to mineralization or mining locations. To compare real with modelled catchment, interpretation of data relied on the use of spidergrams, plotted on a logarithmic scale. In rural catchments, real and model catchment signatures matched closely; in mineralized catchments, the signatures matched closely, although the real signature was slightly higher in Mn, Cr, Pb, Sn, Zn and Zr; and in the urban catchment, real catchment and model catchment signatures did not match for some elements (higher than geological background: As, Cd, Cr, Cu, Ni, Pb, Sb, Sn, V and Zn).

The results from the above assessments found that in the urban catchments with mining and industrialization, heavy metals associated with human activities are much higher than the geological background. Dr. Lass-Evans showed a figure highlighting the enrichment factor of heavy metals, where a figure above 1 would represent human influence. Enrichment factors of up to ten in Pb were found to surround Glasgow, and within a sub catchment, up to 45. Three sub-catchments were metal enriched due to human activities by more than ten times the natural concentration. Looking at historical maps from 1900, it is clear why there are these heavy metal concentrations in central Glasgow. For example, in the early 1900s in the east end of Glasgow, in the area of London Road and Celtic Park, there were a lot of industrial areas adjacent to one another, such as brick, pottery, chemical, engineering, soap and wire works. Even though they were demolished many years ago, they still have an impact on Glasgow’s sediments today.

16.35 Adam Wyness, 2nd year PhD Researcher and Post Graduate Representative, The James Hutton Institute

The Influence of Sediment Characteristics on the Transport of Pathogens from Freshwater to Coast

Current water quality monitoring is based upon detection of fecal indicator organisms (FIO), which are not necessarily pathogenic – the more there are of them, the more chance there is of human pathogens being in the water. By investigating relationships between FIO abundance, sediment characteristics, erosion risk and environmental factors, identification of preconditions to adverse water quality can be explored.

Current water monitoring by SEPA doesn’t take into account FIO in sediments. Water quality monitoring is only carried out during the peak bathing seasons, i.e. summer; yet, E. coli counts tend to be higher in winter than in summer. Bathing water regulations state that SEPA should publish where a certain bathing water area is likely to be affected by short term pollution, and the conditions likely to cause short term pollution. But how can the risk of exposure to pathogens be assessed without knowing how many FIO’s could be re-suspended? If sediment is re-suspended in the water column during high energy events (such as high tide or rainfall), the associated pathogens will be transported to potentially high risk areas such as bathing waters. This research aims to develop a tool to identify which sediments contain a high abundance of FIO and at what time of year, and how prone these

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are to occur in high risk areas (such as bathing waters). An example of such a high risk bathing area is Lunderston Bay within the Firth of Clyde, the closest bathing water monitoring site to Glasgow. In July 2013, a peak of 1600 E.coli units per 100g wet sediment was detected, with a higher count in winter. The European Commission Bathing Water directive states that coastal and transitional water samples should not exceed more than 250 colony forming units per 100ml of water.

The study area for this project is in the Ythan estuary near Aberdeen, which has a high source of fecal contamination derived from the seal colonies that live within the estuary. Long-term monitoring of sediment properties and FIOs is required for this project, and so samples were taken monthly from 4 areas within the estuary, along with an estuary wide sampling campaign, completed quarterly. The analyses found that there is a downward trend in content of coliforms (an indicator of if the water is sanitary) with depth, due to the fact the water chemistry changes 5cm down in the water column - to an organism that is used to living in the gut, this represents a hostile environment. However, mud represents a less hostile environment, and therefore higher concentrations are found. There is also a downward trend in coliform content as the water temperature increases, due to native biota being more active in warmer waters and eating E. coli, which cannot compete against the native bacteria. The study also found that E. coli concentrations in sediment are higher further upstream in the water course due to increasing levels of organic content. The source of E.coli is derived from cattle and other warm blooded animals, especially cows where it thrives as a native gut flora. There is therefore a lot of run off containing E.coli from farmland into upstream areas.

Early conclusions of this study are that depth profiles of E. coli and coliform show that their abundance decrease with depth across all sediment types examined. However, finer sediments allow FIOs to persist for longer at depth. The results of the study will inform policy makers, and help identify sites which need more monitoring of sediments. For example, if coastal management is changed further up the Clyde River, this would result in a change in hydrology of the estuary, and different sediments would get deposited in different places – it is not yet known with any certainty what effect this will have on E. coli distribution and therefore water safety.

16.55 Professor Paul Bishop FRSE, Professor of Geography, University of Glasgow

Closing Remarks

Professor Bishop, a member of the organizing committee of the CUSP conference, welcomed everybody to Glasgow and thanked all delegates for attending today’s session. He sincerely acknowledged the important contribution to science the early-stage researchers brought to the CUSP conference today, and stated that they ‘embody the potential for collaboration in the future’, a key theme for working Europe.

3D lithological model of

Glasgow’s superficial deposits

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Full Day Conference Programme (30th May)

0855 Introduction and Overview

Dr. Diarmad Campbell, Chief Geologist Scotland, BGS, welcomed everyone to the second day of the conference. He reminded the delegates that contributions from the conference, including the early-researchers work from yesterday, will be brought together in a related thematic volume of papers to be published by the Royal Society of Edinburgh.

Much of the CUSP’s work is focused on improving subsurface understanding, particularly the Quaternary deposits. This is facilitated by data acquisition, and the construction of extensive high resolution bedrock and superficial 3D and 4D geological models, which can be attributed in various ways, such as lithology and engineering properties. These models allow us to answer key questions such as the thermal resource in abandoned mine workings and the suitability of sustainable drainage. The ultimate aim is to link all these models together to support decision making in Glasgow. Complementary geochemical surveys have many applications including the impact of soil quality on health.

The BGS work of survey, monitoring and modelling feeds through to a range of experts in BGS, and also externally to local authorities, regulators, practitioners, Glasgow City Council, the ASK network as well as universities, research institutes, and internationally putting Glasgow into a European scale with the COST program. However, if we are to be relevant as a geological survey, have to ascent a scale. To gain maximum impact on decision making, we have to start to develop wider models and make real progress and impact with decision makers on big scale issues such as floods and contamination.

Part of this challenge is to communicate with the wider community. In partnership with Glasgow City Council, BGS have launched a knowledge exchange network, designed to exploit the full potential of work, to provide a free flow of data and knowledge on the subsurface with decision makers. BGS are not solely interested in Glasgow, as Dr. Campbell acknowledged geological surveys have greater relevance to an increasingly urbanized world. In the UK and Europe we are 60% urbanized, and the world is over 50% urbanized. It is predicted that the urban population will increase to 60% by 2030, and 70% by 2050, in line with population growth. The COST ACTION project has many common aims of CUSP, in particular to provide information to those who manage and deliver cities, and to the wider community to make best use of the resources available. Ultimately, we can make a real difference to our cities.

0905 Welcome and Conference Opening

Dr. Campbell introduced and welcomed Sir Kenneth Calman, KCB FRSE FMedSci, Chancellor of the University of Glasgow to the conference. Sir Kenneth Calman described the CUSP project as a vision to raise the profile of Glasgow and the west of Scotland as a world class destination to use science and technology, and as a sustainable economic development. But how do we get greater sustained economic development and an improved quality of life? The topic is very important – over centuries, Glasgow has gone from a medieval place (historically referred to as ‘the dear green place’) to a major industrial centre in the early 19th to 20th century, being the 2nd greatest city of the empire at the time. As an example, Sir Calman pointed out the large crane across the river Clyde from the conference venue, which was built for lifting locomotives built in the north of Glasgow onto boats to be shipped across the empire at the time. Sir Calman referred to classic Scottish poets and their insights into the relationship between geology and the world – Hugh MacDiarmid wrote ‘Earth, thou bonnie broukit bairn’, meaning ‘Earth, you poorly neglected child’, reflecting how humans hurt the earth through climate change. He also wrote ‘what happens to us is irrelevant to the world’s geology. But what happens to geology is not

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irrelevant to us. We must reconcile ourselves to the stones, not the stones to us’. The substrate is very relevant – what happens beneath our feet is critical. Sir Calman then welcomed everybody to this conference, along with a much loved quote regarding the Glaswegian accent: ‘What Glasgow says today, the rest of the world tries to pronounce tomorrow!’

Session 1: Subsurface Knowledge Exchange in Europe and Beyond

Chaired by Dr. Michiel van der Meulen, Chief Geologist, Research Manager Geomodelling, TNO/Geological Survey of the Netherlands.

0920 Ignace Van Campenhout, Municipality of Rotterdam

Urban Planners and the Subsurface: Out of Sight, Out of Mind

Regarding the subsurface as an integral part of public space is not yet common standard practice. Urban planners only make plans at ground level, but do not take them to subsurface level, which is required. Rotterdam has been trying hard to get this point across, and after 7 years is beginning to make some headway. For urban planners, the subsurface is a black box – out of sight, and out of mind, and so it is up to underground specialists to make planners aware of limitations and opportunities by visualizing the subsurface in an enthusiastic way. Rotterdam has developed products and processes to assist with this.

The old approach for urban planners was to consider the underground as a vague area. Therefore, when met with subsurface obstacles such as cable, pipelines and archaeology, these cause delays, and increase costs as their effect has not been considered during planning. Urban planners therefore need to go to subsurface companies, such as archaeology and cable and pipeline specialists for information. These companies are willing to provide information, but each dataset provided is specialist and designed to be used by one specialist in the same sector; not across different sectors (e.g. urban planning). Information from these companies ends up with urban planners, but as each sector records data differently it is difficult for the urban planners to know what to do with it. Is it any wonder the urban planners prefer to delay involvement with the subsurface when faced with such complex data?

The new approach for urban planners in Rotterdam is Underground Scan (U-Scan), developed in collaboration with institutes in Holland, which incorporates subsurface specialists to make aggregated maps for quality, opportunity and economic maps. With U-Scan, the information is not tuned to the needs of the user, but to demands of urban planners. Maps provided are on the same scale, with the same legend in GIS. With such maps, it’s easy early in the planning process to identify areas suitable for redevelopment – for example, Mr. van Campenhout showed a site plan which contained, amongst others, hydrogeological layers (used to highlight groundwater hazards on site) and a soil pollution map translated into a remediation map to show cost for cleaning soil in different parts of the site. Maps like these are taken to the urban planners, and discussed for around three hours at the beginning of a project to understand a site’s relation to the subsurface, and to develop a mutual understanding of the urban planners and underground specialists’ needs.

Urban planners may not like setting up such an initial meeting, as there is an initial upfront cost of time and money, but actually it does help focus on what is happening in the subsurface and how it could affect their project and thus save money down the line. For example, a housing project took place in the north of Rotterdam where semi-detached houses were built in the NE sector, with high rise buildings and underground garages planned for the SW. During construction, a lot of problems were encountered because of unexpected water pressure in soil layers. This led to delays and extra costs, with extra sheet piling requiring construction. Later in the process, the urban planners looked at subsurface maps and found that groundwater pressure was much higher in the SW part of the site than the NE part. This information was available at the start of the project to the urban planners,

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but they didn’t understand it. If they had, then the locations of the flats and the houses could have been switched, thus saving money.

Currently, U-Scan is in 2D (data provided in maps and plans), and now a 3D version is in development. At the start of the project it would be useful for urban planners to have a simple Lego block 3D model to highlight where certain elements of the subsurface are situated.

One of the key stumbling blocks between urban planners and the subsurface is that they have no ambition for it, no imagination of what it looks like – because they are not aware of it. Therefore, Mr. van Campenhout emphasized that education of the subsurface needs to start early, even at primary school level, as the ‘imagination is the basis for formulating ambitions’. As such, Mr. van Campenhout talked the delegates through a 3D game based on understanding the subsurface, which has been developed for Rotterdam: the ‘3D serious game of the subsurface’. The game can be accessed through an online web portal. In this game, the aim is to create a sustainable city by making optimal use of the subsurface. The game shows archaeology, tree roots, ground water pollution, and every player has a limited budget of how to address that and how one factor interacts with another to effectively manage the subsurface. Rotterdam has also introduced an underground city walk to help people visualize the subsurface – it is a simple tool but very effective. Once a month, in a sold out tour, people are guided through the city and talked through the relationship between city development and the role of the subsurface. They are shown major engineering interventions and introduced to how city engineers acquire data and manage it, visualise it, and handle data in 3D models.

0940 Helen Bonsor, Hydrogeologist, BGS

ASK Knowledge Exchange Network for Glasgow and Beyond

In order to develop an understanding of the subsurface, and develop 3D models and improve planning processing, good quality systematic models are required at city scale. However, there are few legislative drivers for this in cities, and new mechanisms need to be found for capturing and acquiring good quality systematic datasets. In all cities, there is a need to reduce uncertainty of subsurface conditions, as they are key considerations in cost and planning processes. In the UK, including Glasgow, there are few legislative drivers for reporting shallow subsurface data to the BGS – often, such data is recorded in PDF format which is difficult to extract data from, and therefore monitoring such data becomes largely useless. BGS found recently that only 18% of data from recent major infrastructure projects can be used with a high degree of confidence: there is therefore a need to maximize past investment in data.

Disconnections in data reporting exist due to limited data access and subsurface knowledge, largely because data is provided in an inconsistent format. Therefore, newly acquired data is not routinely fed into 3D models, resulting in a limited revision of 3D models. As such, decisions are based on site specific data and not in the context of a wider understanding of the subsurface in the city. In Glasgow, the ASK network and GSPEC portal are trying to improve knowledge exchange. BGS and Glasgow City Council (GCC) have been developing this over the past two years to foster a virtuous cycle of data exchange and up to date high quality models. There has been a large uptake and positive response of this initiative between all sectors, as well as with the local government. The key component of ASK is to move to a more efficient means of capturing raw data, by storing it within a centralized repository so that data can be re-accessed and re-used easily. As such, decisions can be based on a wider information database. BGS and GCC have developed a standardized means of reported data – GSPEC (Glasgow SPEcification for data Capture), and requires all users to save data in an AGS format. The data is deposited as raw digital data (to industry standards) in AGS forms (.txt files) to local authorities.

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GCC and Grontmij have officially adopted this system, and have made it mandatory that all their procured ground investigation data will follow the GSPEC format as part of the contract. BGS have also collaborated with the Scottish Government to make it mandatory for those planning applications involving subsurface data to include raw digital data as a condition of submission. The GSPEC portal is held by the BGS, where data can be uploaded via a web portal. The GSPEC portal has an online validation system, which checks for compliancy. If data is not compliant, GCC asks the contractor to resubmit the data in a valid format. Accepted files are stored by BGS, and can be accessed by members of the ASK network and allow BGS to build 3D models.

Knowledge exchange gained under the EU COST program, through visits to Hamburg and Denmark, showed that use of centralized data repository and using data from both public and private sectors is consistent with European best practice. Therefore, the future impact of GSPEC has significant potential. It currently has support from national government, and a potential national roll out once the procedure for Glasgow is refined and improved. European partners want to use ASK as a benchmark of how data management and capture can be used in European cities, where like Glasgow, there are cities with a lack of legislative drivers.

In conclusion, the GSPEC and ASK Network have a high impact in maximizing past investment in data by ensuring high quality systematic datasets and better data sharing today. It improves data accessibility, as data can be efficiently transferred and used where needed, altogether leading to a better understanding of the subsurface and providing efficient savings.

0955 Dr. Michiel van der Meulen, Chief Geologist, Research Manager Geomodelling, TNO/Geological Survey of the Netherlands

BRO: A Revolution in Dutch Subsurface Data and Information Management

BRO is a law developed to regulate the development of subsurface data in the Netherlands, and this presentation explains how the law was brought about.

The Netherlands is a flat country: most of its geology is concealed and there is therefore little indication of deep structures at depth. Therefore, surveying the geology of the Netherlands is a 3D undertaking, requiring drilling, sampling, and measuring, all of which are expensive. The Dutch have a strong tradition in subsurface data management (DINO – an established national service), and have become accustomed to working with data from third parties. For example, under mining law, all data obtained under exploration or production licenses must be handed to the geological survey, who will make them publicly available in 3D models. This is to attract smaller exploration and production companies and encourage them to take smaller fields in the future. It has a maintenance value of 10s of millions of euros, with an asset value of 10s of billions of euros. This data plays a small part in securing 100s of billions of euros in state revenues.

In the deep subsurface, money is made – in the shallow subsurface, costs are avoided. There are different drivers at different levels, arising from the need for 3D spatial planning in a 2D country. 3D spatial planning takes on a layer approach to acknowledge the subsurface, where a layer model distinguishes between three subsurface constituents: occupation (houses), network (infrastructure), then the subsurface. The ministry responsible for the development of the mining law recommended the geological survey plan in 3D, as to plan in 3D, 3D data is required from the subsurface. This is when BRO was conceived – lobbying for the law began in 2007, with investment beginning in 2010 onwards. By law, any government bodies that carry out ground investigation work are obliged to bring the data to TNO, just as with the mining law. It is also required that government bodies use that data whenever they make decisions that pertain to the subsurface. This law therefore promotes recycling of very expensive subsurface data, and 3D models.

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Societal cost-benefit analysis of BRO is undergoing – on a national level the cost of the new system and what its potential benefits are will be calculated. The law is now in the second chamber of parliament, and then it will go to the Senate to address legal technicalities. TNO expect effectuation of the law in 2015 and to implement the system in a modular way. By the time the law is fully functional, it will have taken close to 20 years to develop.

How do TNO manage such a new system? It will have to be integrated with the government, linked to other databases, and TNO’s database will be available directly for users to access. Implementing this change will be achieved by reconsidering and rebuilding all systems and workflows to allow for data standardization. Data standardization is not easy, as TNO will have to consult with all stakeholders and users. Dr. van der Meulen said preparing for the BRO law had used 25% of their survey budget.

Reception of the BRO law by users and stake holders has varied considerably. Municipalities were initially against it, as it comes with a hefty administrative burden. Regional authorities have mixed feelings – they have to invest in the system and finance it themselves, but they understand the need for it. The private sector is starting to see new opportunities. As legislation proceeded, commitment amongst the users also proceeded. The first stage will be to transfer the TNO survey database to a new system, as well as the database of the National Soil Survey. Subsurface data to describe the natural state of the subsurface will be available, and will also include soil and groundwater monitoring networks and anthropogenic influences.

In conclusion, a new law is a sensible idea, but it took a long time to set up. TNO had favourable pre-conditions (a large facility was already in place and required a long term vision, typically longer than planning horizons that we see with national policy makers). Parliament considered not passing the law after TNO had already committed millions to it. This legal status is vital, as it shields us against austerity measures and the process also brings professionalism to the survey.

1010 Hans deBeer, Vice-chair, COST TU1206; Team Leader, Groundwater and Urban Geology, Geological Survey of Norway

COST Action TU1206 Sub-Urban: A European Network to Improve Understanding and Use of the Ground Beneath our Cities

In Oslo city centre, there is a lot of suburban development taking place. However, as the rockhead is down at depths of 80m below the surface, such developments (like new roads) are being built on the infrastructure layer, which contain pipes, sewage, etc. The subsurface is clay and organic rich, representing a problem for road laying – if the roads are not built on piles, they will sink. An InSAR survey over Oslo shows high rates of subsidence in the city centre, particularly around the central train station. New buildings are stable as they are built on piles, but older buildings are sinking. New technology is available to identify settlement in the field that can’t be seen on the ground, and it has been found that Oslo’s subsidence is worse than in Venice. Mr. deBeer explains that Oslo are tackling this issue, and learning ways to avoid damage.

In Oslo, there are conflicting demands on the subsurface. Energy wells are drilled for shallow geothermal heating but there is no application scheme for drilling – a contractor can just drill a well, but once it has been drilled, then it must be reported to the geological survey. There are also a lot of tunnels planned for Oslo, but as the subsurface there contains a lot of archaeology, conflicting demands regarding use of the subsurface arise. Therefore, the geological survey need to try to look at this in a holistic way to make more use of the subsurface information in an efficient way, and as such, have joined COST Action TU1206 Sub-Urban to tackle this.

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The COST Action’s aims are to: provide cities with knowledge and tools to maximize economic, social and environmental benefits of subsurface resources; recognize and manage conflicting demands on the subsurface; safeguard subsurface ecosystem services on which cities depend, and so their sustainability; and address urban geoscience-related hazards. The key aspirations of the COST Action program is to transform relationships between experts who develop urban subsurface knowledge, and those who can benefit most from it (e.g. urban decision makers, practitioners, and the wider research community). Mr. deBeer presented a figure showing a stair-case in knowledge evolution in the use of 3D models of the subsurface in cities, and said ‘as a collective group, COST help each other up the stairs’, to go from building maps and data, to using them to influence decisions. The main objectives are to help each other and co-ordinate with world-leading cross disciplinary research on the subsurface, and share techniques and methods and knowledge – all to inform and empower policy and decision makers, and broaden relevance and impact.

COST is composed of four working groups (WG) to tackle this. WG1 will establish a state of the art in urban subsurface knowledge (city-partner focus, initial 10 case studies, multi-scalar). WG2 will identify/develop good practice, address gaps and develop a ‘Toolbox’ of guidance for key subsurface issues (data availability, monitoring, 3/4D modelling/linkage workflows, and knowledge delivery). WG3 will trial, refine, and rollout that toolbox, including training in and beyond Europe for use in policy, planning and practice (City-partner led). Finally, WG4 will be responsible for dissemination and training, and developing virtuous circles involving practitioners, city-partners, geological survey organisations, and other researchers (driven by early stage researchers).

If COST can deliver information on subsurface data and use it in the planning process, investment can be focussed, and time and money saved. Benefits of subsurface knowledge are being recognised, allowing more free data to become available. COST addresses stakeholders, but they act more like partners, as it is they who drive the actions to tell us what they need in development. How has the COST Action developed since April 2013? It has grown from 11 countries signed up to 23 in May 2014, and is still growing. It has also attracted interest from cities out with Europe, such as Russia and Bangladesh.

COST hope to progress toward their key aspiration of transforming relationships between Geological Survey Organisations, researchers and city partners/practitioners. Another key aspiration is to progress toward a Europe-wide (and selective international) roll out of good practice guidance, and develop a critical mass of users trained in developing subsurface knowledge, and in its improved understanding and use. In terms of expected outcomes, the scientific impact will be to provide improved modelling practise (e.g. integration of deterministic and stochastic modelling), the economic impact will be to improve data and knowledge access, sharing and re-use (e.g. more efficient project planning and delivery) and the social impacts will be a raised awareness on the sustainable use of the subsurface (e.g. improved stewardship and sustainable use of urban subsurface resources).

In conclusion, COST is implementing a scientific work plan, where four work groups will work together to complete a flow chart of different tasks with key milestones along the way. Delivery of the scientific work plan will be produced as reports by the working groups on the COST Action project website, www.sub-urban.eu.

http://www.sub-urban.eu/

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Session 2: Urban Subsurface 3D Property Modelling

Chaired by Dr. Diarmad Campbell, BGS

1110 Dr. Jeroen Schokker, Geologist/Geomodeller, TNO/Geological Survey of the Netherlands

National to Urban Scales of Subsurface Modelling in the Netherlands

‘Model’ is often a misused word: it means different things to different people. At the Geological Survey of the Netherlands, the word ‘geomodel’ is used, and supplies predictions of geometry and properties of the subsurface. The geological survey has stopped producing traditional geological maps, with geomodels starting to take their place.

The geological survey systematically build and maintain two types of nation-wide geomodels: layer-based models, where the subsurface is represented as tops and bases of a series of geological units; and voxel models, in which subsurface properties are represented by a regular grid of 3D cells. These models will become part of the BRO law.

Layer based models are available nationwide, for the upper 500m of the subsurface. They are available as ARCGIS raster layers, and have a resolution of 100x100m, representing geological units with tops, bases and thicknesses along with the uncertainties associated with these and hydrogeological models. A vast proportion of the layer based geomodel is composed of marine sediments from the Miocene upward. In total, there are 31 layers in the geomodel. However, the Holocene deposits are modelled as one unit because it is a complex unit comprising coastal, marine and glacial deposits. Therefore, when the model is zoomed into, we cannot capture this complexity using just a layer based modelling approach. However, there is a lot of borehole data available for the upper 30m of the Holocene deposits, and so modelling of this complex subsurface can be taken a step further by carrying out voxel modelling.

Voxel modelling covers half of the Netherlands (NL), representing the upper 30m of the subsurface, with a resolution of 100x100m horizontally and 0.5m vertically. Each voxel contains geological units and lithological class (sand, clay, peat, etc.). The GeoTOP voxel modelling workflow begins by interpreting core descriptions in terms of geological and lithostratigraphical units. The model is built on a modular basis, where every module has around 50,000 data points within it. Next, 2D interpolation techniques are used to construct surfaces bounding the tops and bases of geological units. The core description data is then returned to in order to simplify lithological distinctions, as the lithology can be enormously heterogeneous. Finally, voxel modelling (sequential indicator simulation) is used to predict lithology for each of the voxels within the geological units.

This kind of modelling captures the complexity within the Holocene unit. Dr. Schokker showed delegates an image of central NL showing fluvial channel belts and their lithological infill, which contained different kinds of sand. Another image showed flood basin deposits surrounding these channels, containing different lithological infills (mostly clay). By running multiple simulations, the clay probability of different lithological classes can be determined.

When geomodelling in the urban environment, use of third-party data is required which is often in different formats. The subsurface changes quickly, and so older data may not necessarily reflect what is underneath the subsurface any more, particularly so the distribution and properties of man-made ground. So how do we model artificial ground?

Model resolution does not always fit application in urban areas, as the geological survey’s modelling resolution is not high enough for urban planning requirements. The geological survey has therefore set up a pilot project to increase the possibilities of applying their 3D

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geomodels in urban areas. The pilot will incorporate additional information to improve model resolution, and come nearer the average application in urban areas. The survey will focus on improved mapping and characterization of man-made ground and develop visualisation techniques to combine 3D geological data with information on the subsurface.

Rotterdam’s infrastructure has changed significantly since it was founded, and as such, understanding the man-made ground for the purposes of urban planning is vital. During World War 2, German aerial bombardment (combined with a fire that followed) razed almost the entire city centre of Rotterdam to the ground. As a result, rubble from WWII has been used as a foundation for the new city centre, and old infrastructural patterns are still visible in the subsurface today. The Municipality of Rotterdam recognized the importance of the subsurface from the early 20th Century, and published books which described all core descriptions at the time. TNO have made this data digitally available, and as a result, have improved model resolution to 25 x 25m horizontally and 0.2m vertically in the subsurface.

Improved characterization of made ground requires a lot of historical information and knowledge. In order to steer interpolation, the geological survey are reconstructing the pre-WWII ground level. As an example, using this level of detail, a combined 3D visualization including geological units, probability on peat lithoclasts and drinking water pipes combined with lithological-class model has been developed by TNO.

To conclude, when considering modelling the subsurface in the future, it is important to fully integrate data in the modelling process, and combine above ground and subsurface data. Thinking needs to be aligned and considered from an object-orientated vs voxelised point of view. In a broader sense, geomodels need to be built with the users, and we need to combine our data and knowledge with them.

1130 Dr. Katie Whitbread, Sedimentary Geologist/Geomorphologist, BGS

How to Present a Can of Worms: Capturing the Complexity of Glasgow’s Superficial Deposits

BGS are developing 3D models in superficial deposits at a local scale in Glasgow. One of the key things with the modelling is to represent the complexity of the geology in Glasgow, which has a complex geological history. It contains a mixture of raised beach, glacial and fluvial deposits, all packaged together in a complex series of strata. It is not a simple layer cake sequence – but rather, a ‘can of worms’. How can we try to understand and capture this complexity?

Traditionally, BGS use 2D maps of superficial deposits to understand them, but this does not give us vital information about their structure, extent and properties at depth. 3D models allow their structure to be visualized and distribution to be tracked, and BGS are developing data into a 3D space to try and apply it in different ways. But how complex do these 3D models need to be? We need to discuss this as a community in the subsurface world.

In Glasgow, data is available from a whole range of existing boreholes logs from the BGS borehole database. There are over 40,000 logs available in the city limit, but these vary in quality and usefulness, and a lot of them are over 100 years old and use old terminologies. As well as boreholes, BGS also have a good historical 2D map datasets, all of which are available to build 3D models. Once data is acquired, BGS use a deterministic modelling approach, which is geologist-time intensive and involves building cross sections and fence diagrams to interpolate surfaces and make a 3D model. The key element of simplification is how to package up sediments. But how do you package them?

Dr. Whitbread explained that BGS uses lithostratigraphy to simplify the model by packaging up sediments: this includes the lithology, stratigraphic level of the unit and the depositional process of how that deposit was created. This is a powerful tool for creating packages of

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sediment, as it tells us how they spatially relate to one another. Simplification is also done by scale, where a nested set of models (block models within urban areas) was developed as well as one which covered the Clyde catchment area.

In the Glasgow urban area, the typical geological sequence is that of older glacial deposits overlain by glacial till, which in turn is overlain by glaciofluvial, glacial, glaciolacustrine, glaciofluvial and raised marine deposits, as well as artificial ground. These deposits are of varying thickness throughout the area – in more complex areas, there is a buried valley with up to 80 m of superficial deposits. In such areas, 2D maps do not show that level of detail and so 3D models are required for visualisation.

BGS has produced a range of products to help understand ground conditions, including GeoSure, which is a geohazard map for the UK. For example, running sand is classed as a geohazard – if it is dug into, it can flow and destabilize the ground. It follows that if one drills through the subsurface, the running sand changes with depth and therefore the risk changes with depth. Along the River Clyde is a key regeneration zone – however there is a complex glaciofluvial domain there and so BGS are working with city partners and site investigation companies to develop high resolution models of such areas.

In conclusion, as a community, we need to focus and manage on how complex the models are so that we can develop outputs that are useful and applicable. BGS have a general overview of models for the Glasgow area, and are looking at how they can move forward in terms of dealing with complexity.

1145 Dr. Alison Monaghan, Geologist, BGS

Big Faults, Little Faults: Multi-scalar Bedrock Modelling in the Clyde Catchment

Geological faults have a range of lengths and displacements within the bedrock geology of the Clyde catchment. As such, they pose a complication when it comes to modelling them at different scales, i.e. faulted 3D models constructed within a geological survey should be consistent between a regional and local scale. Models are not made because of a building going up on a particular site, but are used for any combination of things and as such require to be accessed at different scales. Regional models are generalized, and can therefore not include all faults mapped within them. However, they do provide an overview to guide local models, which include small displacement faults, and in turn their detailed datasets and geometries are resampled to provide data to the regional scale model. This presentation talks through workflows BGS have developed to generalise models built for Glasgow, and how they’ve dealt with a range of different fault sizes in different scale maps.

The bedrock geology of Glasgow consists of a Carboniferous basin which has a long legacy of coal mining and ironstone extraction from the Central Coalfield. This mining legacy has left a wealth of subsurface data for that area, which aids in the construction of 3D models. Throughout the Glasgow area, the Coalfield is cut by numerous faults of different orientations with complicated relationships to one another, and vary in displacement from 1m to 1km plus. In the CUSP project, a total of 794 faults were modelled.

Faults are very important to understand as they play a role in delimiting the extent of the subsurface strata. For example, when the Pope came to visit Glasgow at Bellahouston Park a few years ago, the public were hosted within one area of the park, and did not go into an adjacent area of the park. This was because beneath this area, shallow coal mines exist (with strata displaced nearer the surface due to faulting) which was not safe for 10,000 people to stand on at the one time. In the field in which the public were gathered, faults had displaced the coal seam deeper underground, and therefore mine workings did not pose a threat to the safety of the crowd. Another reason faults are important is that they compartmentalize the bedrock geology into blocks, which is important when considering heat extraction through abandoned coal mines. Faults can also act as conduits and/or barriers to

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flow, and influence how fluid flows in old mines. They also have an influence on rock strength in terms of engineering, as rocks adjacent to faults tend to be intensely shattered and fractured.

BGS used borehole data and legacy coal mine data to build up the faulted 3D bedrock model. Using descriptions and extents of coal mining from mine abandonment plans, along with geological maps, the 3D geometry of faults was modelled. BGS used a mixture of GOCAD modelling software and the in-house BGS software GSI3D.

Dr. Monaghan showed delegates an example of a site specific 3D bedrock model built for Shieldhall in Glasgow, where a major sewage tunnel was planned. The 3D model included faults which were proven, mapped, or interpreted from available data, and guided site specific issues such as the planned tunnel route, sites with mine water escape and subsidence hazard assessment from shallow coal mines. Going up to local scale models (1:10,000 to 1:25,000 km), the central Glasgow bedrock model included faults with over 30 m throw, or if they were over 2 km in length. This helps guide planning and regeneration, such as Commonwealth Games sites and the Clyde Gateway, as well as providing a basis for heat from mine waters. Mapping at a regional scale (1:100,000 to 1:250,000 km), faults over 100 m throw or significant mapped offsets were modelled, and such models can be used to learn about the development of the Carboniferous basement and controls on deep aquifers with geothermal potential.

Each of the above multi-scale models contain different criteria for fault inclusion – but they are consistent between models. The rules for inclusion/exclusion of faults depend on fault throw, length and fault dip. For example, when comparing cross sections of two models at different scales (site specific and regional scale), Dr. Monaghan illustrated to the audience that whilst numerous small faults captured in the site specific scale were not present in the regional model, the largest faults were, and synclines and anticlines captured in the site specific model were also represented as, albeit simpler, structures in the regional model. Such a study of cross sections from different models illustrates model consistency and generalisation from local to regional scale.

In conclusion, a wide variety of CUSP bedrock models have been created over the past 10 years. Faults at a range of scales exemplify the problem of model consistency, which are also inherent in the stratigraphic surface. Models of different scales and types from the Clyde Catchment have played a major role in developing procedures for consistent multi-scalar models at BGS.

1200 Andrew Kingdon, Petrophysicist and Team Leader Parameterisation and Statistics, BGS

Stochastic Modelling of Glasgow’s Superficial Geology

BGS exists to answer questions for the UK Government, academic researchers, UK industry and at any point in between, including the public. BGS is moving from an answering ‘what is’ to a ‘what if?’ approach, in order to understand the impacts of hidden ground conditions such as: subsurface properties on surface drainage, subsurface properties on containing or reactivating anthropogenic contaminants and subsurface risks to essential urban infrastructure. BGS currently have lithostratigraphic maps to define the generalized geology, with 3D models to define geological structure. However, lithostratigraphy does not adequately describe geological heterogeneity to support decision making – in other words, models imply a simple facies distribution. Therefore, new techniques are needed to understand subsurface variability.

BGS are employing oil reservoir understanding to help explore the superficial deposits below Glasgow. Glasgow represents a good case study for employing a new approach to understanding the subsurface, as it is a large post-industrial metropolis with redevelopment required for new industry and housing. Glasgow also has a legacy of contaminated industrial

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sites which require remediation. Glasgow City Council are an exemplar stakeholder – they are not broken up into separate authorities, and as such can work with the BGS to provide a unique detailed database of subsurface properties to help model the subsurface.

Sediments are heterogeneous by nature – for example, the Gourock Sand Member is not composed entirely of sand, but of sand with some silt, clay and locally gravels. How can we understand if this heterogeneity affects a project? Stochastic modelling can be used as it applies a random function to describe how something varies. Boreholes can be tied into the modelling to help give a less random outcome. 500 simulations were carried out on the Glasgow model, in order to assess how much individual packages vary in an attempt to visualize them. The lithologies of the superficial deposits in Glasgow are, at this stage, stochastically modelled on a 3-D grid, and physical properties can be extrapolated throughout this grid. Properties include density, which is derived from geotechnical density borehole data, and a lithological mean derived by point by point calculation of the model. A bulk density procedure enabled the study of 3D physical properties of the surface and subsurface, and highlighted zones of poor ground conditions. This process can be iteratively improved as new data becomes available. Bulk density derivations has been undertaken multiple times and has been subject to rigorous peer review, so results are repeatable, and the workflow well understood. Another physical property that can be extrapolated throughout the 3D grid is that of hydraulic conductivity, which is derived from particle size distribution. Models can be filled with hydraulic conductivity data in order to understand flow properties of superficial deposits. An example given by Mr. Kingdon during the talk showed a probability map of the likelihood of flow conductivity in a part of Glasgow, where he showed zones of low runoff (low conductivity) and high runoff (high conductivity). In the latter zones, there is a danger of higher inflow which might cause the superficial deposits to reactivate, and provide potential pathways for contaminants.

In conclusion, stochastic property models enable solutions to solve societally relevant problems. BGS have developed a workflow to create robust stochastic models on a city-wide scale. Data standards resolve both data variability and quality control problems, which is of benefit to all stakeholders. The ASK Glasgow network is an exemplar of a mechanism for providing such data, and CUSP Glasgow has shown vision in developing this for the benefit of the city. If developed elsewhere, these types of databases will facilitate development and management of contaminants in other UK cities. Parameterised physical property analysis in 3D allow an understanding of city-wide subsurface conditions; aid developers in avoiding unforeseen ground conditions; and help in decision-making in planning development. Stochastic 3D modelling could be used, for example, to identify contaminated sites with high hydraulic conductivity, which risk reactivation of contaminants. Such models directly improve understanding of the development and potential of urban land, and will help in pre-planning of site-investigations. It also provides information not available from traditional mapping or 3D modelling, and allows development of iterative geological models which can be easily updated as new information becomes available.

1215 David Entwisle, Senior Engineering Geologist, BGS

Geotechnical GIS of Glasgow

Geotechnical GIS provides a simple method of accessing geological and geotechnical data. It is a desk study tool, consisting of geological information (from 3D models) and geotechnical (geoenvironmental) information and data. The data that BGS deals with from Glasgow and the ASK network is available, but problems remain of confidentiality from geotechnical companies – still, 95% of geotechnical data has been made available. Mr. Entwisle presented a 3D geological model of central Glasgow, composed of basic engineering geological classes. Different colours represent mixed units (e.g. sand, gravel and clay, or sand and gravel mixed with clay, etc.), along with stiffness and grain size properties of lithologies. Using such a 3D model can help urban planners understand the geotechnical properties of the subsurface without having to go through raw data (e.g. site investigations, borehole records, etc.).

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Site investigations produce huge varieties of different data. In situ data includes geology, core rotary data, casing diameter etc. Lab data also provides chemistry, particle size, etc. All geotechnical data available has been added to the National Geotechnical Properties Database, and Glasgow (via the ASK network) will have access to this database. The National Geotechnical Properties Database holds geotechnical information extracted from site investigation records provided by clients, consultants and contractors, and from field and laboratory testing carried out by the British Geological Survey. Much of the data is abstracted from high-quality site investigation reports conducted for major trunk road and other construction schemes. For central Glasgow, there are a total of 100,800 boreholes, of which 43,411 are available in AGS format, as well as over 2.7 million data points available. The database tables and fields are based on current Association of Geotechnical Specialists (AGS) industry standard digital format. Where required, extra geological information related to stratigraphic classification and lithological descriptions are included. Information held within the database includes: locations to British National Grid coordinates; borehole, core and in situ test data; sample data; and a range of laboratory index and mechanical property test data on both soils and rocks.

BGS want to make this data more accessible and easily available. The Geotechnical GIS is a desk study tool on which a wide variety of data can be shown. It includes specialist data produced by the BGS, including solid geology, superficial geology, anthropogenic units, mining information, hazard information (such as landslides), digital geology, 3D modelled geology and geotechnical information. The Geotechnical GIS also enables summary plots to be drawn, to, for example, give an idea of variation within the data, and to look at a plot of plasticity vs liquid limit. It is also possible to construct a box and whisker plot showing uniaxial compressive strength for different units, as well as summary plots using descriptions from boreholes, such as stiffness and weakness. This provides a simple way to visualize rock strength and other geotechnical properties across an area.

BGS would like to see this approach of a Geotechnical GIS taken to a national level. In summary, GIS provides a method for presenting 2D and 3D modelled geological information, and for accessing a wide range of information and data. Data can be displayed in summary graphs and diagrams, and data is accessed dynamically from a database.

Session 3: Urban Geochemistry and its Wider Context (soil, sediment and surface water quality)

Chaired by Fiona Fordyce, Senior Environmental Geochemist, BGS. This session will discuss water and soil quality, and its relationship to the mobilization of harmful substances.

1335 Fiona Fordyce, BGS

Geochemical Baseline Surveys of Glasgow and the Clyde Basin: Overview and Soils

The BGS national strategic survey for geochemistry is called G-BASE. Urban geochemical surveys commenced in the 1990s, with soils in 27 urban centres surveyed to date, including those from Glasgow. The first phase of the G-BASE Clyde survey was carried out in the 1980s and sampled rural stream sediment, with a second phase following from 2001-2004 to collect urban soils and urban stream sediment/water. A third phase ran from 2010-2011 to collect rural stream water and urban and rural soils.

The Clyde Basin extends from the Lowther Hills in the Southern Uplands to the Firth of Clyde on the west coast of Scotland. The uplands are characterized by peaty heather moorlands, with the main arable agricultural areas situated in the centre of the basin, and urban areas within the Glasgow conurbation. Glasgow was a major powerhouse in the 19th – 20th centuries, and as heavy industry declined, it left behind a legacy of pollution. The Clyde Basin geology (which has an influence on the geochemistry of a region) is composed of Silurian and Ordovician rocks composed of greywackes and volcanic rocks to the south

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with younger Carboniferous sedimentary (coal-bearing) and volcanic rocks composing the Glasgow area. Devonian sandstones occur in the centre and north of the Clyde Basin.

BGS have an extensive dataset of stream sediment and surface water samples. In 2011, BGS collected a set of soil samples from particular land use sites. The soils were collected using an auger based on a systematic grid, where 4 samples were collected per km2 in urban areas, and 1 per 2km2 in rural areas. The top 5 – 20cm of soil is usually sampled and analysed using XRF and assessed for pH and LOI (Loss on Ignition) as organic matter indicators.

Chromium (Cr) in soil within the Clyde Basin is found in areas underlain by volcanic rocks and in the south of the basin. However, in the Clyde Plateau lavas, Cr values are not systematically high, possibly due to the lavas being more evolved here than elsewhere, a factor reflected in the soil. Looking at Cr distribution in urban areas, values are typically high in man-used soils. For example, there is a high distribution surrounding the Ravenscraig site, which was home to the largest steel mill in Europe until 1992. There are also large concentrations of Cr in the top soil in Rutherglen, which hosted the largest Cr works in the world until 1960s. BGS found that 20% of urban and 11% of rural soils exceed the guidelines for human health in chromium within Glasgow.

Selenium (Se) distribution is affected by organic matter influence. High values are controlled by soil organic matter, and have elevated concentrations in select urban/industrialised areas: yet no soils exceed the soil guideline value. However, the soil is deficient in Se near the Clyde in Dumbarton, where it has developed over Devonian and Carboniferous sandstones. Soil deficiency in Se can be detrimental to the health of grazing animals.

The lead (Pb) distribution throughout the Clyde Basin is particularly high within the area of the Leadhills, an area historically mined for Pb and other heavy metals. Mining activity has dispersed lead into the environment. Additionally, Pb values are also relatively high in organic rich soils surround Glasgow, as well as elevated levels recorded in sites of previous industrial heritage (e.g. Ravenscraig). Soils within Glasgow city centre also have concentrations of lead, related to former use of lead in petrol, lead in coal burning, and lead in paint. 6% of urban and 1% of rural soils in Glasgow exceed guidelines for human health in Pb.

Regardless of the geological parent material, many metals (especially Ca, Cu, Pb, Sb, and Sn) are two to three times elevated in Glasgow. This is a typical indicator suite of urban anthropogenic pollution, which is also found in other cities. The urban soil quality is a result of natural and anthropogenic inputs, and as such a legacy of urban/industrial pollution remains 40 years after major industrial decline.

Soil data has a wide range of applications including characterizing soil quality across the Clyde Basin, investigations into sources of Pb in Glasgow soils and looking at the link between soil quality and deprivation and health. BGS are currently working with hydrogeologists to assess threats from pollutants in soils leaching into shallow groundwater. This exercise has highlighted there is a lack of groundwater data available in Glasgow, which has helped drive the ASK network. BGS are producing the Clyde Soil Geochemical Atlas to provide a basis and reference for policy and planning and research in the future.

During question time, Ms. Fordyce said that Glasgow has the highest Cr content out of all other UK cities, with Swansea coming second (it also has a history of metal processing). Interestingly, cities like York and Lincoln haven’t had a lot of industrial work, and as such heavy metals are much lower and more related to the geological background.

1350 Dr. Jenny Bearcock, Hydrogeochemist, BGS

Mapping the Water Chemistry of the Clyde Basin Drainage Network: Regional Context and

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the Urban Imprint

Drainage of the Clyde Basin was sampled in a number of phases. The Clyde inner estuary was sampled in 2002 – 2003, with 122 tributaries of the Clyde sampled in 2003 to aid in understanding the urban environment and how it affects water. The major part of stream water sampling was undertaken in 2010, where 1786 samples were taken. 60 samples of the River Clyde and major tributaries were also taken around this time. At each site, water samples were collected, and analysed for pH and alkalinity.

The chemistry of stream water is controlled by numerous, often interlinked factors, including rainfall chemistry and pattern, soil type, geology and human influence. A map presented to delegates showed the average annual daily rainfall across the Clyde Basin, where the lowest rain fall occurs over the central and eastern parts of the catchment. The highest rainfall falls over the north west and south catchment boundaries, in particular over upland areas. The rainfall is clearly related to topography, with most rain falling over the hills. These upland areas are typified by hills, heath and bog land, which is also typically where peat is found. As streams are fed not only by rainwater but by groundwater flowing through bedrock aquifers, the geology is also important for stream water chemistry. For example, the Clyde Plateau Volcanics and Ordovician Silurian strata are hard rocks with minerals that do not dissolve easily and as such do not change the water chemistry very much. However, the Carboniferous sedimentary rocks (composed of limestone, mudstone and coal bearing sandstones) are much more easily dissolved, and therefore contribute more to stream chemistry.

BGS combined rural stream waters and urban Clyde tributaries into one data set to create an interpolated map covering the whole of the Clyde Basin. The first map presented to the delegates looked at the pH level in the waters sampled. pH levels are important as they influence mobility of various elements. The most acidic stream waters tend to be around the catchment periphery, and in areas underlain by peat. The area downstream of the Leadhills mining area is also acidic as fresh reactive surfaces of naturally occurring sulphide ore minerals are exposed, and increase reactions with rain water to give rise to acid mine drainage. Glasgow is generally neutral to alkaline.

Conductivity within water samples is a measure of solutes, i.e. how many dissolved solids are present within the water. Around the north, west, and southern boundaries of the catchment, the conductivity is low. This is related to rock type (typically difficult to dissolve volcanic rocks), high rainfall (where water runs off and doesn’t react with rocks) and land use. The centre of the catchment has a higher conductivity, where the rocks are easier to dissolve and lower rainfall means that water is stored in the rocks for longer. Some areas of high conductivity within the catchment are caused by coal mining. The process of mining breaks up the rocks and creates a greater surface area which the water can interact with.

Chromium distribution within the Clyde Basin is of particular interest as there is a history of chrome production in Glasgow. Chromite ore processing residues were landfilled, and tons of chromate waste dumped around Glasgow. The Chromium anion is more soluble at more alkaline pH values: as the urban area has an alkaline pH, Cr is likely to be mobile in water in those areas, and thus can be leached from soils and transported into streams around Glasgow.

Lead concentration within waters of the Clyde Basin is highest in the Leadhills area. Lead is more soluble in acidic streams – in Leadhills, which has an acidic pH, it is mobilized but likely to be deposited in the more alkaline pH conditions found within urban waters in Glasgow. This explains why there is a low Pb concentration found in the urban waters of Glasgow. However, if the urban waters of Glasgow were acidic, Pb would remain in solution and be carried further downstream until it reached more alkali conditions.

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BGS are producing a hydrogeochemical atlas of the Clyde Basin in the near future which explains these findings in more detail.

1405 Professor Marian Scott OBE FRSE, Professor of Environmental Statistics, School of Mathematics and Statistics, University of Glasgow

Soil Quality and Health/Deprivation Indicators in Glasgow

The environment plays an important role in moderating health and wellbeing, but the relationships between environmental factors and health and wellbeing are complex, with many interactions. Exposure to environmental risk factors is not equally distributed, and links between poor health and environmental inequalities (e.g. inferior housing, crime and industrial emissions) form part of the Environmental Justice Agenda. This project is a masters by research project, and will provide an assessment of geo-environmental inequalities in the Glasgow Conurbation. A Scottish Government report stated ‘we have to deal with a substantial legacy of land which is already contaminated. It is not known, in detail, how much land is contaminated’. Various estimates, including figures from the Environment Agency, have suggested land ranging between 100,000 and 300,000 hectares is contaminated, but only a small proportion of these pose an immediate threat to human health and the environment.

Professor Scott quoted from Gemmell and Scott (2013): ‘Environmental regulation is a fundamental means of securing sustainable development. Regulations should have a focus on real environmental outcomes, including the state of the environment and the hazards focusing on tackling harms and risks.” Glasgow is well regulated, and wants to place a focus on protecting the environment. Underpinning this protection is a need to know and understand the local geological soil information.

For this investigative study, 10 different metals were considered from the G-Base Soil data set, and observed at specific sampling locations. The study aims to build an environmental index: a set of aggregated or weighted indicators, a composite numerical value that helps provide insight into the overall state of the environment. Taking fundamental raw soil concentrations and aggregating them together in a principle framework will allow derivation of an index that can be associated with a geographical or aerial unit, in line with the way most offer health data is presented in Scotland. The study looks at spatial associations between soil metal content, air pollution, deprivation and health across Glasgow.

The results found that poor soil quality is spatially associated with areas of deprivation, and demonstrated statistically significant associations between respiratory case rates and soil metal quality. Of the individual soil metals, only nickel showed a significant relationship with respiratory cases. However, these types of observational study do not examine causality, but simply report the spatial concurrence or association between deprivation, soil and health, where there are many confounding factors. This is no measure of individual exposure (population study) and there may be an ecological bias. Nevertheless, soil quality should be taken into account in environmental justice indices in the future.

1420 Professor John Farmer, Professor Emeritus and Senior Honorary Professorial Fellow, University of Edinburgh

Chemical Speciation and Bioaccessibility of Chromium in Contaminated Glasgow Soils

Taking a walk along the River Clyde in the east end of Glasgow 100 years ago, walkers would have come across White’s Chimneys, a chemical works which processed Chromite, using the roasting by high-lime process. This process converted chromite into chromite salts, leaving behind a Chromite Ore Processing Residue (COPR). This residue was typically disposed of by putting it into any convenient holes in the ground – whilst the chemical works closed in 1968, a study of the groundwater from nearby found yellow coloured Chromium 6 (Cr (VI)) contaminated water. Cr (VI) is a specific form of Cr – it is highly mobile at high pH in its anionic form.

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Seven sites nearby Shawfield were identified with elevated Cr (VI). Typical analytical data obtained for COPR found that pH was very high (11-12) and that a quarter of the total Cr found is Cr (VI). Cr (VI) was also found in groundwater up to 90mg/l, and in surface water up to 6.5 mg/l. What are the processes controlling the release of Cr? Professor Farmer explained the study looked at the solid phase speciation of COPR minerals, and looked at XRD methods to determine the major mineral concentrations within COPR. Three important phases were found – ettringite, hydrocalumite and hydrogarnet (crystalline phase) all of which contain Cr (VI). 20-25% of the COPR that is in Cr (VI) form could be held within these minerals at pH of 11-12. There are a variety of chemical processes that can affect Cr, including reduction, oxidation, precipitation, dissolution, absorption at lower pHs and complexation with organic ligands.

As Cr (VI) is bad for human health, it is important to gain an understanding of how Cr left in soils from Glasgow’s industrial past could affect human health. Professor Farmer used two examples of how Cr can affect the human body – through ingestion of Cr into the gastrointestinal system, and through the lungs.

The Unified Bioaccessibility Method, which mimics the chemical environment of the human gastrointestinal system, was applied to 27 BGS G-BASE soils, including several with Cr (VI) in secondary minerals arising from disposal of COPR. Oral bioaccessible Cr was higher in the COPR-affected soils, but Cr (VI) was reduced to Cr (III) during ingestion. In terms of bioaccessibility in the lung, Cr (VI) is a proven lung carcinogen. There is a possibility of contamination via dust created from site disturbance, as Cr (VI) can penetrate cell membranes whereas Cr (III) cannot.

1435 Professor Andrew Hursthouse, FRSC

Anthropogenic and Natural Geochemical Factors on Urban Soil Quality

Urban soils are very unique as we are continually exposed to them. We do not know much about them, but yet we interact with them every day. It is important to consider urban soils for a number of reasons: planning and management of urban systems and link to health; urban soils are unusual, and fall outside of normal domains; they support the risk assessment of land contamination; and are important for future legislation. Urban soils are a mixture of ‘additions’ with the normal soil, which includes mineral and organic material, and space and moisture. Typically the location of urban soils is defined on 2D maps, but not their structure, as they are very variable.

Following a pilot study, where teams were tasked with obtaining samples from public open space which had been undisturbed for as long as possible, results found variability within urban soils. For example, there was variability found in urban soils for mercury content in undisturbed soils, and using histograms to plot the impact of a city on the soil properties, it was found that there are also significant changes in the pH levels within the city administrative borders. But how can we tell where this variability comes from? We can assess the physical and chemical influence on soil properties – typically 3-4 distinct factors were found: pollution (affecting Cu, Pb, Zn, Cr and organic matter), urban inputs (pH and Ca), parent materials (Ni, Al, Cr, Fe) and texture. Land use (gardens, public open space, riverside, roadside) show some ‘special’ contributions, with general chemical features the same. For example, it was found that in larger cities (such as Glasgow) there are strong pollutant signatures effecting urban soil variability.

Urbanisation mobilizes bad elements such as lead, which has an impact on human bioaccessibility. Urbanisation also has an impact on forest soils: statistically significant (p<0.0001) differences in forest floor carbon stock are seen for urban vs non-urban forest soils, and therefore the carbon stock in the forest floor is a sensitive indicator to urban impacts. Non-urban forest soils have higher total carbon stock than urban – a combined

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impact of urban process and land management.

In conclusion, urban soils are inherently more variable than natural soils, and have a higher loading of potentially toxic elements and other parameters. Statistical methods can help define influencing factors, such as multivariate analysis (e.g. cluster, PCA, etc.) and spatial assessment (GIS) and interpolation. Urban (forest) soils contain a higher portion of extractable potentially toxic elements – which are mobilized and can be bio-accessed. Source strength and trends in contamination are a priority to assess in the future.

Session 4: Urban Groundwater, Estuary and Marine

Chaired by Brighid ό Dochartaigh, BGS.

1535 Paul Meyer, Hydrogeologist, Groundwater Modeller, CONSULAQUA Hamburg

Groundwater Modelling and Monitoring in Hamburg

Hamburg is the 2nd largest city in Germany, with a total area of 755km2 and 1.8M inhabitants. The metropolitan region of Hamburg contains 4.5M inhabitants. Key drivers of the project are the BSU (Ministry of Urban Development and Environment) and Hamburg Water (water supply company) and CONSULAQUA (private consultant owned by Hamburg Water). Hamburg is covered with Quaternary deposits (sand, silt, clay and till) from the last three glaciations. Typical structures within the Quaternary deposits include buried valleys, which have been cut more than 400m deep into the underlying Tertiary strata, consisting of Miocene clay, silt and sand layers. Disrupting this strata are salt dome structures which have an importance in the water supply of Hamburg, as there are certain problems with salinization in freshwater resources or sinkholes. Hamburg’s water supply is fully based (100%) on groundwater resources (17 waterworks in the city area and the near surroundings).

Hamburg has 4000 groundwater monitoring wells, but they are maintained by various operators, and the quality of monitoring site development is not always known, and quality of collected data not always reliable. Therefore, the installation of efficient systems of data collection (e.g. data logger) required a consequent optimization of Hamburg’s groundwater monitoring system. The city now has 646 groundwater level monitoring wells and 167 groundwater quality monitoring wells.

High resolution 3D geological models provide a reliable base for groundwater modelling. A 3D model has been built by BSU Hamburg, constructed using 250 borehole data, cross- sections, maps, seismic and geophysical measurements. CONSULAQUA have built up a groundwater model for numerical modelling. The model was set up using ‘SPRING’ software as a 2D FE-Mesh with a model area of 4500km2. The model is a combination of wells, surface waters, buried valleys and salt domes. For the 3D numerical model, data was taken from the 3D geological model from the BSU containing 16 model layers and around 1 million model nodes. To construct the 3D model, cross sections were imported into GoCad, digitized, and then exported into the numerical model (SPRING).

Groundwater modelling and calibration took a lot of time to carry out, and required a lot of measured data – 2800 measured data for monitoring wells were used for calibration of 4 aquifers. Following calibration, the measured hydraulic head against the calculated hydraulic head had a good fitting. As well as this steady state calibration, a transient calibration was carried out from 2005 – 2011, which again had a reasonable fit between measured and expected.

Using the numerical modelling, local scenario runs can be carried out on a smaller section of the model extracted from the regional model. The smaller model can then be reinserted into the regional model. Mr. Meyer explained that they carried out a flow simulation using a method called inverse transport to show catchment areas for each well and aquifer. Groundwater surface interaction can also be modelled, by using STRING, a module within

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SPRING that takes data and shows streamlines and where groundwater flows. As well as showing the results as a simulation in 2D, it can also be visualized in cross-section.

Applications of the groundwater model will allow an understanding of the regional water balances, and also an assessment of the regional groundwater flow. It will also allow an assessment of the impact of new supplies, development of source protection zones, influence of existing catchment areas, salt water intrusion problems and optimization of groundwater and surface water measurement programs by using the results from the groundwater model.

1555 Stephanie Bricker, Hydrogeologist, BGS

Urban Groundwater: A Pilot Monitoring Network for Glasgow

There is no systematic groundwater monitoring system in place within Glasgow. To address this, BGS are working with Glasgow City Council to develop a pilot monitoring network to inform a longer term monitoring strategy. Urban groundwaters represent varied environments which are changed by human influence. There is little monitoring of shallow aquifers within the UK - most of our groundwater resources come from deeper bedrock aquifers, and as a result, there has been little need for a focus on shallow aquifers. Despite this there is a lot of data out there which includes information on them, such as site investigations, and there has been an increase in the last few years regarding urban groundwater research – with an emphasis on recharge and contamination. However, such data only provides pockets of information rather than the city scale overview which is required.

A city scale overview of urban groundwater is required so that we can understand more about our baseline environment. Urban water cycles are different from regional water cycles. Over the last few years, there has been devastating flooding, but what is the role of urban groundwater in that? What is the role of sustainable urban drainage in dealing with surface water? What is the contamination history? These issues can only be answered if we have an understanding of urban groundwater, which is currently hindered due to a lack of a monitoring system and network.

Site investigation data may be Glasgow’s best chance of getting an urban groundwater monitoring system set up. Can we use site investigation data to understand urban groundwater at a city scale, and can it ultimately be used to develop a pilot monitoring scheme? Whilst collecting site investigation data between 2004-2011, BGS identified 300 groundwater monitoring boreholes around Glasgow. However, there were a lot of issues with these data – site investigations don’t always run for years, and may only run for a few months, or even minutes. Such site investigations are found within the major redevelopment areas of Glasgow, such as the site of the Commonwealth Games, Shawfield, M74 and the Clyde Gateway. However, their spatial coverage is not good, as there tends to be a lot of clustering and most of them follow the valley of the River Clyde itself.

In most cases, the boreholes from the site investigations were not suitable for a pilot groundwater monitoring study. More than half of them have an unknown starting height, and in nearly all cases we didn’t know which geological unit the borehole was monitoring. With a large proportion of the data being uncertain, the next steps were for BGS to develop a hydrogeological conceptual model and feed the 3D Glasgow geology model and site investigation data into it. That way, BGS can cross reference models with borehole logs and start to look at how groundwater varies within geological units and find spatial variation in groundwater levels. Following the conceptual model, BGS gained a better understanding of how the groundwater system was behaving, allowing them to implement the pilot study.

At first, BGS designed a pilot monitoring network to focus on 3 geological units: the Gourock Sand, Bridgton Sand and the Paisley Clay. The monitoring frequency should be at least

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monthly, and monitor groundwater levels, temperature and conductivity. BGS have installed data logging systems in 6 boreholes chosen out of 22 potentials. However, within one month of the pilot, one of the boreholes was vandalized, and so BGS currently have 5 boreholes monitoring groundwater conditions within the Paisley Clay (3 boreholes) and the Gourock Sand (2 boreholes). No boreholes were suitable to monitor the Bridgton Sand. BGS now have 2 years worth of data for this, and can now start to look at the difference between geological units and look at relationship with rain fall, trends with distance from the River Clyde and draw out tidal influences and a conceptual model.

Looking longer term, SEPA will be taking over a longer term monitoring of boreholes with an ultimate goal of extending and expanding the monitoring network. When new site investigations are planned, SEPA will ask contractors if the boreholes they will be drilling are suitable for monitoring and if they can be used for that.

In conclusion, site investigation data is very valuable in terms of pulling them together to get a city overview of groundwater systems, but there are still limitations to overcome. Networks such as ASK and GSPEC really help with this, and a pilot network is good to test conceptual models before implementing wide scale monitoring networks.

1610 Dr. Majdi Mansour, Senior Groundwater Modeller, BGS

Groundwater Modelling to Improve Conceptual Understanding of Flow under Glasgow

Groundwater modelling in the urban environment is required for remediation of pollutants (present because of Glasgow’s industrial legacy), and to assess the role that groundwater plays in urban flooding. It is also required to study the impact of groundwater flows on structures such as road tunnels, building basements etc., and to predict future system behaviour. To represent groundwater modelling BGS have used Glasgow as a study area. BGS used numerical models e.g. the ZOOM suite (groundwater software), to develop a conceptual model - a set of illustrations to define the study area extent, boundary conditions and describe groundwater flow processes.

A simple groundwater model was used to test a conceptual model, using a numerical model to test the conceptual model. BGS began trying to model groundwater flow in Glasgow in 2008. The 2D geology map of the superficial deposits was used to define the extent of the superficial deposit aquifer. Glasgow has a very complex superficial geology, and so GSI3D was used to provide insight into the subsurface geometry. With a 3D geological map available, BGS went through the process of identifying different properties of lithologies and looking at the hydraulic properties of these lithologies. A map was constructed showing thicknesses of units which had groundwater characteristics, and it was found that superficial deposits could not make a continuous layer across the city, and that there were two key components within the Clyde catchment - the Clyde Valley Aquifer, and the Proto-Kelvin Valley Aquifer.

The conceptual model of Glasgow’s groundwater system is composed of two layers. The first layer includes the Clyde Valley Aquifer, superficial deposits where they exist and till deposits. The lower layer includes the Proto-Kelvin Valley Aquifer, and bedrock. The model receives recharge as input and discharge as output through the River Clyde. For this model, it is assumed that the Gourock Sand Member and the Bridgeton Sand Member constitute highly permeable shallow aquifer units; that they are in hydraulic continuity with each other and the River Clyde; and that they contribute to the regional groundwater flow.

It is also assumed that the Cadder Sand and Gravel Formation also forms a significant aquifer unit, and that the bedrock aquifer accepts recharge over higher ground through thin till and till-free windows; and that it transmits groundwater down-gradient towards the River Clyde.

BGS created a numerical model which has the same extent as the original model, but in this

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model they included the two layers and each layers hydraulic conductivity values depending on their nature. The bedrock was modelled as having 1m of flow per day, the till at 0.1m a day and the sand at 100m per day. BGS ran the model to steady state and compared results at 141 boreholes which were mainly centered in the middle of Glasgow. This gave BGS groundwater flow and heads comparable to observed ones within 2m approximately, suggesting that the bedrock can transmit water down to the Clyde, and that the other major aquifers, the deep sand Proto-Kelvin Valley aquifer to the north and the Clyde Aquifer play an important role by passing the groundwater flow down gradient.

In conclusion, this presentation showed how 3D geological modelling informed BGS to improve our conceptual models, and that the conceptual model was tested by the numerical flow model which confirmed that it was acceptable until proven wrong. We would like to have further data to compare our model to, so that we have more confidence in it to apply for future scenario modelling.

1625 Professor Michael Heath, Professor of Fisheries Science, University of Strathclyde

Urban Dependence on Coastal Seas – Glasgow and the Firth of Clyde

Glasgow’s economic power and trading potential is founded on the Firth of Clyde and its connection to the Atlantic. The Firth of Clyde also provides us with seafood, sea angling, scenic value, wildlife and sailing to name a few. This talk will focus on the fishing aspect.

Despite chemical and nutrient influence, fishing has an effect on the ecosystem. Historically, the Firth of Clyde had a prosperous fishing background. There were pelagic fisheries (for herring, mackerel, and other fish high in the water column that eat plankton), demersal fish fisheries (fish that live on the bottom of the sea, e.g. cod, haddock, whiting and plaice) and also shellfish fisheries (lobsters, scallops and crab). By the 1960s, fishing had gone from being net or line/creel fishing based to dredging and trawling based.

Herring fisheries go back many centuries in the Clyde, where up to 20,000 tons of herring were fished a year. However, in the 1980s the fisheries collapsed, and there is no commercial scale herring fishing in the Firth of Clyde now. It is a similar story for the demersal fisheries – demand peaked in 1970s, but today it is almost zero. However, shellfish fisheries have expanded and represent some 20% of the UK catch. This decline in fishing in the Firth of Clyde has had an effect on Glasgow’s economy, in that speciality seafood restaurants are now almost completely unable to catch locally caught fin-fish, and instead it has to be imported.

There is a long history of regulations to try and protect fish stock within the Firth of Clyde. In 1889, the whole of the Firth of Clyde was closed to trawlers – it reopened in 1984, only for parts of it to be closed again come 2001. It is considered a ‘turbulent zone’ for fisheries. There are polarized views about why the fin-fish fisheries collapsed, between creel fishers and trawl fishers. A majority of trawl fishers believed the Clyde was not overfished whereas the majority of creel fishers believed it was; 77% of creel fishers thought that trawling in the Clyde was not a sustainable method, whereas 70% of trawl fishers thought it was. In 2010, an ecological meltdown was declared in the Firth of Clyde, and hit the headlines with sensationalist titles such as ‘Clyde ‘cleaned out’ to become marine desert’ (Sunday Times). However, this was based on fish landings which are not a good indication of what is really going on in the sea – merely a representation of what the ships brought back to land.

Professor Heath explained his research group gathered together research vessel survey data from 1927 to 2011 to determine what was going on in the sea. They found a decline in the landings of fin-fish, and a rise in nephrops (shellfish) landings. However, in the sea, the biomass of fish hasn’t changed much – but rather, smaller fish have taken over the system completely. The legal landing size is 27-30cm, and so there are no fish of commercial

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interest. The growth rates of haddock and hake for example have decreased, which may be a genetic response to intense exploitation, as the fishing industry has sieved out fast growing, later maturing fish, leaving a genetic strain that is predisposed to slower growth.

Species which comprise 85% of the biomass of the Firth of Clyde has changed from a diverse range in 1920-1959 (including small sharks and big hakes), whereas now there is only one species left which comprises 85% of the biomass, the whiting. Economic output from the Clyde is still high, but it still only has a few boats and employees – fin-fish fisheries have more or less gone, and the fishing scene in the Firth of Clyde is now dominated by nephrops and scallops, which are mostly exported. As well as the above, this research has also found that the Clyde demersal fish community has undergone a transformation: total fish biomass was high in the 1920’s but now comprises of fish which are less than 40cm in length. There are changes in fish growth rates and reduction in size at maturity, and no loss of fish species richness: but much reduced species evenness.

The key scientific questions that we need to answer are: are there any interventions that would promote a change in the state of the Clyde to one in which large fish are once more abundant? Are there benefits to a 3 mile limit trawl ban? Are by-catch rates of demersal fish in the nephrops trawl fishery inhibiting recovery? It is a political issue that needs to be addressed, and not something that science can answer. What is the societal aspiration for the ecological state of the Clyde? The answer to this has implications for Glasgow, its port facilities and infrastructure, employment and training, food supply and transport, and tourism and planning.

1640 Dr. David Jones, Project Leader/Geochemist, BGS

Estuary and Marine Contamination in the Clyde Catchment

Estuaries are important habitats for fish, shellfish, birds and mammals, but are subject to human impacts from urban centres. This impacts up the estuary and from the seaward side as well as from urban centres such as Glasgow. Estuaries act as sinks for sediments from both marine and fluvial sources. Contaminates, which are stored in sediment, have the potential to harm biota and have the potential to be stored for large amounts of time, disturbed and re-brought out in the long term. Few studies have looked at this – there are legislative drivers and treaties like OSPAR, which has a very challenging aim of trying to get concentrations in the marine environment back down toward zero for man-made substances and back down to background levels – not an easy task.

The initial part of the BGS investigation used geophysical techniques to obtain scans of the sea bottom in the River Clyde: shallow seismic profiles and boomer, sidescan and multibeam scans. A multibeam bathymetry plot resulting from this work (from 2007) was shown to the delegates by Dr. Jones, who pointed out a range of features on the sea floor within the Firth of Clyde. An interpretation of the data saw a mixture of glacial and postglacial natural features such as moraines, troughs, landslides, and also bedrock, as well as dredge spoil and strange triangular marks - interpreted as being jack up rig marks. BGS then used this data to place observations of near surface sediments in an overall context, and to give some sort of feeling for Quaternary history up to the present day.

Different surface sediment types were also mapped. The amount of contamination is driven by sediment type – the finer the sediment, the more contaminated it will be. The outer part of the estuary turns more to mud and is most notable in the deep water area in Loch Long. There is a different sediment type in the man-made dredge spoil disposal area.

Geochemical work was also carried out – a whole range of sampling of both surface sediments and shallow cores took samples of sediments down to 2-3m. These sediment samples were analysed to look at a range of inorganic and organic geochemistries and background data on particle size analysis and mineralogy/petrology of the sediments. All of

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the results were pulled together in GIS, with the aim of distinguishing background levels of contamination in the estuary, and to look at processes controlling contaminant migration through the river system into the estuary.

Taking Pb as an example, higher levels were found within the inner estuary and outer estuary. Another approach taken was to look at sediment guideline levels and how the values of other elements compare to those guidelines. Canadian freshwater sediment guideline values were applied to Glasgow. It was found that As, Cu and Zn exceed sediment quality guidelines, but there were many more sites along the Clyde where Cr exceeded sediment quality levels.

BGS also looked at the natural background levels within the sampling area, rather than just using guidelines developed elsewhere. What are the baseline values within the estuary? The deeper within the sediment core, the older the sediment and therefore sediment recorded there will have been deposited pre-industrial era. For example, a muddy core which doesn’t change a great deal in look, changes in concentration of Cr, Pb and As down to near constant values after 50cm. Therefore, these lower readings were taken as a natural background value and then compared with surface values.

BGS can then look at a sample which exceeds background value by a certain number, and can also look at PAH’s, and at the occurrence of different isomers. Pyrolitic PAH’s from burning (coal burning) are predominant in the inner Clyde area – further down the estuary there is more of a mixture of burning and petroleum products (petrogenic, oil and diesel spill contamination). BGS also looked at the distribution of elements down some of the core, including a number of man-made elements such as PCB, where they first appeared. PCB’s first appeared in 1940, and reached a peak in production and use in 1970, and were then banned in 1980. The cores record this history well, and record a general profile which follows historical use and discontinuation of contaminants. For example, Caesium distribution comes from atmospheric weapons testing in the 60s, from Sellafield discharge in late 1970s, and from Chernobyl – within the cores, major peaks are seen relating to Sellafield and double peaks relate to Chernobyl. The Pb isotopes also tell a story: it picks up the early days of mining, moving later into petrol lead signature (originally from coal and then from petrol production) decline at the top of the core due to stoppage of lead in petrol.

In conclusion, contamination within the estuary reflects industrialization of the area, and the historical evolution of industrialization. The contamination source can broadly be defined within the area, but not the individual source. The form and bioavailability of contaminants needs to be established before their impact on the ecosystem can be assessed.

1700 Dr. Martin Smith, Science Director, BGS Global

CUSP: The Global Dimension

Dr. Smith started work with the CUSP project 10 years ago, and in this presentation will look beyond what has been achieved in Glasgow, and how it might be applied in the global community.

Three take home messages from this conference are the importance of partnership, transformation of relations and data sharing on a common platform, and holistic approach. By 2050 we will see humans living in urban settings increase to 70%. There is still a major mismatch between communities; how do we bridge that gap between social and natural scientists? As demand for space and resource increase, an understanding of the subsurface is absolutely key and as important in any economic data in a city. The urban agenda is therefore high on the BGS science strategy.

Cities around the globe occur in different settings, different geologies, and the cities have different ages and stages of development. Our cities saw a massive expansion in population

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coincide with industrial revolution. Consider cities in South Korea: a population of over 50M people, of which 80% live in an urbanized environment. That is the equivalent to living in a land area two and a half times smaller than the UK. South Korea’s cities have developed in the last 50 years, responding and developing on a different timeframe than the UK. However, these modern cities have not yet been tested by the ‘once in 100 year’ storms, and haven’t built up resilience as our established cities have during natural and human events. These are fundamental differences between the UK and South Korea.

India is planning to build a corridor between Delhi and Mumbai, which will have 7 new smart technology cities. But a lot of the urban planners there don’t have a thorough understanding of what is beneath their feet. The UKaid department for international development by Atkins and UCL London report highlights a ‘perfect storm of risks facing cities’, within the report ‘Future Proofing Cities’. It’s an important issue in the work we are doing in Glasgow and how it can be applied around the world.

To understand urban vulnerability we require subsurface information. What are the questions a city authority might ask? How much is down there, how deep, how do we manage space? Do we have enough aggregate for construction? An alternative way of looking at the issue is looking at a triangle diagram encapsulating what CUSP has been doing. This built a platform of information constructing geological through to processing models and taking out intelligent solutions. But what does the user of the data really want to do with it? That is the key question to deliver subsurface solutions in the right manner.

The impact of CUSP has been on: environmental health (geochemical atlases, sediment soil and water, spatial relationship of soil quality); resilience to climate change (early stages of looking at groundwater flow and aquifer recharge, pioneering new shallow groundwater monitoring); ground stability (voxellation of near surface superficial deposits and artificial deposits crucial for longer term planning); energy modelling (underground resources, 3d mining structures to underpin renewable energy); and subsurface planning (developing common platforms like ASK and GSPEC).

Future proofing analysis breaks down cities into five categories, but does not consider the subsurface. Glasgow is classed as a type 1 city (energy intensive, sprawling, with an industrial subsurface). When compared to Singapore, it is quite different – Singapore is a type 4 city, meaning it comes with multiple risks, including energy carbon and climate hazards. It also has complex geology that hasn’t been exploited. Singapore is 4x the size of Glasgow. A recent government paper from Singapore suggested population will increase to 6.5 million by 2030. To account for population growth, Singapore plan to double the rail network which will place huge demands on surface space; they are therefore developing a subsurface land use master plan. Key to this is understanding their rock space, as there are three tiers of development planned: a shallow level of utilities (water, gas, sewage); transport (metro system, offices, malls, car parks, down to 50m); then deeper rock cavern program for hydrocarbons, water, land fill, cable tunnels, pump storage hydro schemes and thermal storage.

CUSP lessons for Singapore: for a new mass rapid transport system, there is a need for prediction of near surface deposits by stochastic modelling. For rock cavern exploration, there is a need for bedrock modelling understanding and communication of geological processes (e.g. faults) and groundwater resource assessment. BGS also have a global dimension, and are starting to spread out across the globe with BGS urban projects developing in SW Asia and the Gulf.

The next steps for CUSP are for the Glasgow Urban Earth Observatory: a platform for integrating multi-use and multi-scale data, development of innovative sensor technology, building a research and user community with common goals and exploiting GSPEC with consistency in data. In conclusion, this project has realised the benefits of transforming

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partnerships and communications, recognized the importance of data availability, acquisition and re-use, discovered how to design workflows, and adopted a holistic approach to scale of development.

1715 Professor John Coggins, OBE FRSE

Closing Remarks

‘This meeting has been the dream and vision of Dr. Diarmad Campbell. He approached Paul Bishop, and convinced the Royal Society of Edinburgh and Glasgow City Council that they would facilitate the meeting to display this wonderful project. As a chemist who became a biologist, I found that there was real vibrancy in this meeting. You as a group capture the multidisciplinary nature of science and engineering together with talking to the planner. This project is a wonderful exemplar and will provide many opportunities within the future. This has been an outstanding meeting and I have enjoyed meeting a lot of people, and have learnt an incredible amount.

‘Thank you to Diarmad, Paul, Oonagh, and to the Glasgow Science Centre staff – this centre is a very special place, and to have our conference hosted on a typical day in the Science Centre with all these young minds around us is very apt. Also, a thank you to BGS who have underwritten the meeting financially, to COST, and to GCC for their involvement in the project and their hospitality. It’s been a brilliant meeting, thank you all.’

Topography: Ordnance Survey (OS) data crown copyright all rights reserved 100037272

Geoscience data © BGS, NERC. From Fordyce F M, Everett P A, Bearcock J M, Lister T R, Gowing C, Watts M, Barker K, Ellen R and Scheib A.

In Prep. Soil Geochemical Atlas of the Clyde Basin. British Geological Survey Open Report, OR/14/032.

Chromium distribution in soils map within the Clyde Basin, with ‘hot spot’ explanations

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Conference Organising Committee

Professor Paul Bishop FRSE

Professor of Geography, University of Glasgow

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Dr. Diarmad Campbell

Chief Geologist Scotland, British Geological Survey

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Oonagh Carroll

Events Officer, RSE

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Professor John Coggins OBE FRSE

Former Vice-Principal for Life Sciences and Medicine,

University of Glasgow

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Report written by Dr. Rachael Ellen

Opinions expressed here do not necessarily represent the views of the RSE, nor of its Fellows

The Royal Society of Edinburgh, Scotland’s National Academy, is Scottish Charity No. SC000470

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