Carrak Consulting

Carrak Consulting

Mining Consultancy, Carrak Consulting, have received a fully funded £5k grant from AeroSpace Cornwall to enable knowledge transfer between AI specialist, Jane Gallwey Surveying, for the analysis of hyperspectral drone data. The funding will accelerate their new project, which aims to use the data to identify areas of arsenic contamination at abandoned mine sites. 

Carrak is investigating the use of a novel remote sensing technique to help understand mining related pollution of river catchments.

Hyperspectral remote sensing has potential applications for tracking heavy-metal polluted soils, but is currently an experimental and expensive technique. The aim of this research project is to establish if there is a cost-effective way to capture spectral remote sensing data that will allow arsenic contaminated soils to be identified and mapped without the need for lengthy or specialist data processing.

Contaminated land is a material consideration under the National Planning Policy Framework. Soils in Cornwall frequently exceed soil guideline values for arsenic, which dictate safe thresholds for human health, and so must be remediated when land is developed. Arsenic also disrupts the metabolism of plants and much remains unknown about its effects on crop health.

This project uses hyperspectral data collected from a UAV to map the reflectances of soils across 273 spectral bands. These mapped reflectances are then used in two ways. Firstly, high contrast false-colour images are generated which accentuate areas of high heavy metal pollution for visual interpretation. Secondly, areas of high arsenic observed by Portable X-Ray Fluorescence (PXRF) are matched to other soils bearing similar spectral characteristics across the study area. 

Innovative machine learning algorithms have been developed to map this data. Although these are currently waiting to be deployed as they require larger sample datasets to determine their effectiveness, it is hoped that these algorithms could further revolutionise hyperspectral heavy metal pollution analysis across the region. 

With a view to increasing accessibility across the industry, the workflows developed for this project have been entirely implemented with open source software, removing the requirement to purchase expensive hyperspectral software suites. Further research is required to build a spectral matching model for the wider Cornish mining landscape; however, the continued development of this innovative technique could lead to the creation of a spectral signature library of soils across Cornwall, enabling accelerated analysis of large areas of soil in a way that has not been attempted before.

This project demonstrates that remote sensing techniques can also be used to enhance the responsible and sustainable development of natural resources. Cornwall continues to offer opportunities for mineral exploration, which can be realised by marrying traditional industry with space and aerospace innovations. 

To find out more about Carrak Consulting, contact AeroSpace Cornwall.