Soil maps could hold the key for urban planning
Research by BGS has developed a predictive model to evaluate levels of bioaccessible contaminants in urban soils and their relationship with the underlying geology and former industrial land use.
18/01/2022 By BGS Press
As cities across the UK strive to breathe life into formerly industrialised areas, there is growing concern about potential negative effects on human health and the surrounding environment from concentrations of potentially harmful elements (PHEs) found in soil.
It is therefore essential to understand not only the total concentration and spatial extent of PHEs in urban soils but also, through bioaccessibility measurements, the potential hazard they pose to human health. This knowledge can then be used by planners and developers to help minimise potential health impacts and provide guidance on the best redevelopment land use.
Scientists at BGS applied a geochemical modelling and mapping approach to predict the human availability (bioaccessibility) of PHEs to over 700 surface soil samples taken from Stoke-on-Trent and believe the method could be applied to an archive of soil samples held by BGS from numerous urban centres.
The research is published in the open access journal Geosciences, published monthly online by MDPI.
The modelling found that the county’s former industrial heritage influenced the concentrations of bioaccessible arsenic and lead. The method, which combines soil samples with unified BARGE method and random forest modelling, could help to predict the bioaccessibility of soil contaminants in other urban cities.
Mapping of predictive data is essential to support urban redevelopers and policy frameworks when it comes to identifying and prioritising sites for suitable regeneration.
Developing bioaccessibility maps using our modelling and mapping approach provides an important resource for contaminated land risk assessments and land-use planning, and could be applied as a standard approach for other urban centres.
Joanna Wragg, lead author, BGS.
The industry of Stoke-on-Trent has left a landscape rich in industrial heritage characterised by once-widespread bottle kilns, canals, wharfage and disused railways.
Once home to the pottery industry in England, it is documented that over 100 potteries have emerged in the county since the 1700s. The manufacture of colours and chemicals for potteries, glazed brick manufacturers, glassmakers and enamellers was common across the region, their variety and decorative colour dependent on metal oxides.
Stoke-on-Trent was also home to numerous steel and iron works, the largest being the Shelton Bar Steelworks, which stretched across the Etruria Valley and, at its height, employed a workforce of 10 000 and included multiple coal mines, steelworks, rolling mills and blast furnaces before finally closing in 2000.
Naturally elevated concentrations of PHEs are also found in the coal measures that surround the city. The Staffordshire coalfield supported the development of Stoke-on-Trent as an industrial city.
The rapid growth of the local pottery and steel industries, and the supporting large coal industry, resulted in widespread urban growth that combined residential, retail and industrial developments. Today, regeneration of the city has re-purposed these once industrial areas of potentially contaminated land for new industrial, residential and community use.
It is precisely this range and distribution of past and present industrial activity in urban areas like Stoke-on-Trent that provides a challenge for understanding the complex mixtures of contaminants in soils, which in turn are heavily influenced by geological and environmental processes.
Soils act as sinks and sources of PHEs, which in turn are heavily influenced by the underlying geology, environmental processes and the way in which previous land use determined the nature and deposition of contaminants.
We chose to study the concentrations, bioaccessibility and spatial distribution of arsenic and lead as common priority soil contaminants for human health risk assessment. Use of this model suggests the source of both of these elements is driven by heavy industrial and human activity.
Understanding these sources of contamination and, as a result, the potential mobility is therefore important in evaluating potential for and the impacts of re-purposing land for other end uses, which could include green spaces and urban housing.
Joanna Wragg, lead author, BGS.
The soil samples were part of BGS’s Geochemical Survey of Urban Environments (GSUE) project, an integral part of wider G-BASE and TellusNI programmes.
The geochemistry maps were superimposed onto the Ordnance Survey New Popular Edition historic map (one inch to one mile) of Stoke-on-Trent (1940s) using QGIS to visualise linkages between the industrial past and the spatial soil geochemistry of the area.
Latest news

Dr Marie Cowan awarded the Energy Group Medal by the Geological Society
18/05/2023
This award is presented annually to individuals with a geoscience background who have made an outstanding contribution to the energy industry

BGS appoints new members to Science Advisory Committee
17/05/2023
Four new members’ three-year terms begin in June 2023.

AGS file utilities tool: production release
16/05/2023
BGS’s online tool for validating AGS files against the official AGS data format rules and its own NGDC data submission requirements goes live.

BGS releases 10K maps through updated maps portal
16/05/2023
BGS releases an updated maps portal, which allows users to view all publicly available, maps and includes 10 000 and 1:10 560 scale maps for the first time.

BGS maps out priorities with five-year strategy
11/05/2023
BGS publishes its new strategy for 2023 to 2028, ‘Understanding our Earth’.

Improvements to borehole delivery
25/04/2023
BGS releases improvements to its borehole layer on the GeoIndex, which makes access faster and improves quality.

Report identifies areas of the UK prospective for critical raw materials
17/04/2023
Areas from the Highlands to south-west England have the right geology to be prospective for several critical raw materials such as lithium and graphite, according to a new report.

World Mineral Production 2017 to 2021 is now available
14/04/2023
The latest edition of World Mineral Production has been released.

How does public water use influence the amount of phosphorus in the environment?
11/04/2023
New research looks at how phosphorus accumulates in public water systems in the USA.

Scientists discover regions of the UK with greatest potential to use heat from deep thermal waters
30/03/2023
BGS geologists have mapped the UK’s potential to use heat from thermal groundwater deep beneath central and southern Britain.

BGS laboratories become first in UKRI to receive gold LEAF accreditation
28/03/2023
BGS achieved gold certification in the Laboratory Efficiency Assessment Framework (LEAF) accreditation in March 2023.

World Water Day 2023: groundwater photo stories
22/03/2023
A showcase of groundwater use from around the world highlighting how developing groundwater has benefited the lives of many people.