Satellite geo-mapping contract awarded to monitor Welsh coal spoil landslide risks

The Coal Authority, established in 1994 to manage the geotechnical and environmental impacts of past coal mining, has appointed geotechnical firm Central Alliance to remotely measure levels of hidden moisture at coal mine spoil tips in Wales utilising satellite technology previously used to search for water on other planets.

Central Alliance will carry out data collection and analysis across 10 Welsh local authorities under the project funded by a grant from the Welsh Government.

Groundsat, developed by the Wakefield-based ground engineering company in partnership with satellite technology specialist Asterra, will rely on space-borne remote observation to confirm the levels of moisture in soil below ground level at and close to coillery tips.

GroundSat, which uses space-borne remote observation techniques, has been developed in collaboration with satellite technology partner Asterra, pioneers in the detection of water on earth using L-Band Synthetic Aperture Radar.

It will allow Central Alliance users to remotely measure soil moisture levels below ground level, assessing sites and identifying geotechnical risks or drainage issues before they have an impact on critical infrastructure, construction projects and development sites.

The work has been commissioned under a Welsh Government grant scheme to promote coal tip safety, and follows on from landslides at a tip in Tylorstown in February 2020 following heavy rainfall during Storm Dennis.

Subsequent analysis of the risk following the slope failure revealed the slope stability problems could be more widespread and affect many more coal spoil tips in South Wales.

The project is due to start this month, with a second phase early next year, and undertake data collection and analysis across 10 Welsh local authorities.

The assessment will confirm the effectiveness of existing drainage systems and identify any hidden moisture which could represent a future risk.