- Evaluation of the resource potential of mine waste for the sustainable recovery of critical metals
- Enhanced assessment and monitoring of environmental impacts of mine wastes and their reprocessing and remediation
- Development of novel integrated observation tools (i.e. volumetric geophysical imaging coupled with mineralogical/ hydrogeological studies) for mine waste characterisation and environmental monitoring.
The overarching objectives of the project are to develop novel ground imaging approaches to determine the spatial distributions and concentrations of critical metals in mine waste (i.e. resource potential), and to assess potential environmental impacts of reprocessing and remediating versus leaving sites undisturbed.
A legacy of the centuries of mining in the Cornubian Orefield has been the production of large volumes of mine waste. Our hypothesis is that some of these wastes will contain economic quantities of critical metals (e.g. tin and tungsten) when reprocessed using modern approaches.
However, the assessment of this potential resource is challenging. These materials (including waste rock, spoil, tailings and slags) are difficult to sample and characterise due to considerable heterogeneity at both the clast and site scale, there is variable supergene alteration, and their depth is largely unconstrained. Furthermore, these wastes have the potential to cause significant negative environmental impacts (acid mine drainage and toxic metal release), which could be exacerbated during reprocessing and/or remediation.
Our focus will be on developing geophysical tools (supported and validated by mineralogical and hydrogeological studies) to volumetrically image and characterise these wastes. We will deploy an integrated suite of methods, coupled with supervised machine learning, with a view to classifying the waste and developing resource distribution models for selected trial sites. These same geophysical tools will also be used to develop 3D ground models defining waste structure and underlying geology and 4D models of soil moisture dynamics and groundwater flow to improve our understanding of the environmental implications of disturbing historic waste.
We anticipate that the approaches developed within this project will significantly advance the state-of-the-art for mine waste characterisation, and will be applicable beyond the Cornubian context. Consequently, once an approach has been established and trialled, we will seek to develop pilot studies with international colleagues at other mine waste types, e.g. copper-gold tailings.
The project will be a collaboration between the British Geological Survey (expertise in hydrogeophysics & mineralogy and materials characterisation), University of Leicester (economic geology and mineralogy), Camborne School of Mines (economic geology & Cornubian Orefield), and Terradat (UK) Ltd (applied geophysics).
This is a CENTA Flagship Project
This project is suitable for CASE funding
HostBritish Geological Survey
- Climate and Environmental Sustainability
- Dynamic Earth
Jonathan Chambers, British Geological Survey (BGS) ([email protected])
- Gawen Jenkin, University of Leicester ([email protected])
- Dan Smith, University of Leicester ([email protected])
- Eva Marquis, CSM, Exeter University ([email protected])
- Rich Crane, CSM, Exeter University ([email protected])
- Alicja Lacinska, BGS ([email protected])
- Chris Bird, Terradat (UK) Ltd ([email protected])
Key techniques will include: electrical resistivity tomography – ERT (sensitive to lithological variability, moisture content, and contamination); induced polarisation tomography – IPT (sensitive to the present of metals and electrically conductive minerals); seismic refraction tomography – SRT (sensitive to lithological and geomechanical properties variations). The techniques are strongly complementary – having differing sensitivities to a range of materials types.
Resource potential: By analysing the correlations between the various geophysical properties and mineralogy (determined using Scanning Electron Microscopy with Zeiss Mineralogic, and X-ray Diffraction) we will develop geophysical proxies to build resource distribution models through supervised machine learning (i.e. classification of waste types).
Environmental impacts: ERT, SRT and direct mineralogical and hydrogeological sampling will allow us to build 3D ground models of mine wastes and their environs. This will provide a foundation on which to use 4D ERT and hydrogeological monitoring of moisture driven processes – thereby improving our understanding of potential environmental impacts.
Training and skills
Students will be awarded CENTA2 Training Credits (CTCs) for participation in CENTA2-provided and ‘free choice’ external training. One CTC equates to 1⁄2 day session and students must accrue 100 CTCs across the three years of their PhD.
Supervision/informal training: The student will be hosted at BGS, but will spend ~20% of their time at Leicester University. BGS and Leicester supervisors will operate an open-door informal supervision policy, and will hold 3-monthly supervision meetings with all BGS, university and industry supervisors.
Formal training: A wide range of taught training courses are available from BGS and Leicester. External training opportunities will be available and identified on the basis of need.
Industrial Placement: The student will spend at up to 3 months embedded with Terradat – gaining experience and training in a range of near surface geophysical techniques relevant to the project.
Partners and collaboration
The project has been co-developed between BGS, Leicester and Exeter Universities and Terradat. All partners will be involved in supervision and student training (including Terradat). In addition, Terradat will provide CASE support and host the student for an industry placement.
The supervisory team have well established links with regulatory agencies and legacy mine site land owners in order to enable access to study sites for this project. Supervisors also manage datasets on mine waste composition in order to facilitate site selection.
Prof Jonathan Chambers, British Geological Survey, Nottingham ([email protected])
Prof Gawen Jenkin, Leicester University ([email protected])
If you wish to apply to the project, applications should include:
- A CENTA application form, downloadable from: CENTA application
- A CV with the names of at least two referees (preferably three and who can comment on your academic abilities)
- A completed University of Leicester application form available here: https://le.ac.uk/study/research-degrees/funded-opportunities/centa-phd-studentships Please quote CENTA23_BGS1 when completing the application form.
Applications to be received by the end of the day on Wednesday 11th January 2023.
Literature review; test site identification; initial desk-based data/information collection for test sites; preliminary laboratory testing (using existing repository of mine waste samples totalling >100kg); initial site visits and reconnaissance surveys; training in geophysical and analytical techniques; development of detailed project plan and schedule.
Main programme of field survey and monitoring (we anticipate that several field sites will be utilised); laboratory work focussed on petrophysical relationships (e.g. linking electrical and mineralogical properties) and controlled tank scale simulations (in the order of 3m3) to guide field-scale survey design; thesis and paper writing (paper 1 published); conference attendance.
Years 3 and 4: Data elaboration; attend international conference; thesis and paper writing (papers 2 and 3 submitted and/or published; thesis submitted).
- Dimech, A., Cheng, L., Chouteau, M., Chambers, J., Uhlemann, S., Wilkinson, P., Meldrum, P., Mary, B., Fabien-Ouellet, G. & Isabelle, A. (2022) ‘A Review on Applications of Time-Lapse Electrical Resistivity Tomography Over the Last 30 Years: Perspectives for Mining Waste Monitoring’, Surveys in Geophysics, doi.org/10.1007/s10712-022-09731-2.
- Fitch, V., Parbhakar-Fox, A., Crane, R., Newsome, L. (2022) ‘Evolution of Sulfidic Legacy Mine Tailings: A Review of the Wheal Maid Site, UK’, Minerals, 12, 848.
Systems for migrating from office to home-based working have been developed during Covid by all collaborators – in the case of further pandemics we anticipate that similar approaches could be successfully followed. Likewise, safe working systems have also been developed for laboratory and fieldwork – but as these activities necessitate more human iterations these protocols are more restrictive. In the event of another pandemic, mitigation would include refocussing the project towards desk-based data manipulation and modelling aspects of the project, with a reduced focus on laboratory work and fieldwork requiring close working with others.