Until now utility companies have come under an exemption in the regulations around the classification of excavated waste from utilities installation and repair. This exemption comes to an end in June 2022, and following a transition period it will be necessary to classify spoil and process any contaminated/hazardous material in line with environmental regulations.
This project will look to prove that existing hyperspectral imaging technology can be used to detect contaminants in spoil under laboratory conditions at the levels needed to meet the standard. Once this has been completed the project will look to develop a prototype, handheld device suitable for use on site and carry out field trials.
Benefits
By demonstrating that a handheld device can accurately detect the presence of contaminants in spoil on site the necessity laboratory test, including the transportation costs, can be removed.
Learnings
Outcomes
The project has produced learning that suggests there is potential for using HSI technology to identify the presence of contaminants, and potentially also specific contaminants, in soil.
However, the third deliverable report recommends that further work should be undertaken before HSI technology is considered for deployment. This is due to the limitations outlined below, which would benefit from further exploration:
- Reference materials were not representative of genuine soil. They were guaranteed to contain only one contaminant, when genuine soil would likely contain a mix of contaminants.
- Contaminants were limited in the range of concentrations, as they were pre-prepared samples.
- Trials were conducted using artificial lighting, which ensures consistency and is therefore not representative of natural light in real world conditions.
- Full evaluation would require further samples to cover all contaminant types that might be encountered in soil.
The third report also suggests that a VNIR camera, the lowest-cost option, is unlikely to be suitable for this purpose, but that the NIR camera has the ability to identify the presence of contaminants, and the SWIR camera, the highest-cost option, has the ability to identify some specific contaminants in a soil sample. It will therefore be necessary to conduct further work to construct and evaluate potential use-case scenarios and identify the associated cost and benefit.
Lessons Learnt
There is potential for the use of HSI technology in the detection of contaminants in soil, which could lead to a reduction in the costs associated with disposal of hazardous waste, dependent on further investigation.
Future projects should focus on testing the following to determine whether results would be reliable and replicable in field conditions:
- Testing genuine soil samples that might contain a mix of contaminants at a range of concentrations.
- Testing using natural lighting and in a range of field conditions.
- Testing a wider range of samples to investigate whether all contaminant types that might be encountered in genuine soil can be identified.
- Testing a range of cameras produced by different manufacturers.
During the project it became apparent that availability of technology from third parties may be limited, so this should be factored into the planning phase of future projects to ensure that the required apparatus can be tested within the project timeframe.
Learning also demonstrated that a solution might require higher investment than originally anticipated, as the HSI camera with most potential for identifying specific contaminants is the high-cost SWIR camera, which may also be less practical for use outside of a lab setting. Therefore, it will also be necessary to develop some potential use case scenarios and produce a cost benefit analysis to determine how suitable HSI technology is for this purpose.
