Scotland has a strong coal mining heritage. Few signs of the coal industry remain above ground today, but thousands of kilometres of abandoned underground workings lie beneath what is now prime development land. When considering planning applications, local authorities have to evaluate the risk of gas leaks from these historic mine workings and ensure the correct mitigations are put in place to protect infrastructure and public health.

The vital importance of this planning process was brought into sharp focus in 2014, in the village of Gorebridge near Edinburgh, when around 200 residents of a new housing estate reported health issues including nausea and headaches. High levels of carbon dioxide from disused coal mines were detected, and the entire estate of 64 new-built homes had to be demolished.

Following the publication of national industry guidance by CL:AIRE in 2021 on how best to assess mine gas risks, BGS joined forces with the engineering firm WSP and North Lanarkshire Council to develop a decision-support tool using Esri’s geographic information system (GIS) technology. At the time, teams at North Lanarkshire Council were spending a lot of time evaluating mine gas risks on a site-by-site basis and engaging with planning applicants on sites with complex ground conditions.

BGS created the initial prototype of the decision-support tool within just a few weeks. It then built the solution using Esri’s ArcGIS Experience Builder app builder in ArcGIS Online and refined it iteratively over a period of six months in collaboration with WSP and North Lanarkshire Council. During the project, BGS prepared the data for the decision-support tool using ArcGIS Pro, consolidating its own geological data with data under a zero-cost, public sector license from the Mining Remediation Authority. The final solution was then hosted in North Lanarkshire Council’s ArcGIS Online system.

The coal mine gas risk decision-support tool is now being used by the pollution control, planning and building standards teams at North Lanarkshire Council, as well as the council’s appointed contractors, including WSP. Users draw polygons around proposed development sites, and the tool automatically calculates and presents colour-coded risk scores for every 50m2 area within the site. The tool allows users to drill down to get detailed information on risk factors, such as the proximity of mine entries, boreholes and mine workings.

To support the introduction and ongoing use of the coal mine gas risk decision-support tool, BGS created an intuitive and highly visual user guide with the ArcGIS StoryMaps app builder. Easy to follow, the guide includes a worked example, enabling new users and contractors to start taking advantage of the tool very quickly.

Expedited planning applications for new developments
North Lanarkshire Council is expected to save a significant amount of time, as staff and contractors no longer have to manually search through different datasets to apply the CL:AIRE flow charts to calculate mine gas risks. Consequently, the council can make faster decisions and expedite planning approvals. “Mine gas screening is just one part of the planning process,” explains Dr. Darren Beriro, Principal Geoscientist at BGS. “However, by speeding up this vital stage, councils can use geoscience evidence to help approve new developments more quickly, supporting Government objectives for new housing and investment.”

Greater trust in the mine gas screening process
The new decision-support tool provides North Lanarkshire Council and third parties with accurate data and a standardised approach to assessing mine gas risks, which fosters greater trust in the council’s mine gas screening procedures. “Our new ArcGIS-based tool brings together the most authoritative data sets, giving councils, contractors and developers a shared view of the best available information and confidence in the process,” says Beriro.

Reduced complexity in the mitigation of health risks
Critically, the new decision-support tool reduces the complexity of the process of screening for coal mine gas risks. This makes it easier for councils to ensure that gas risks are correctly and consistently screened at an early stage in the development process, to help prevent a repeat of the infamous Gorebridge incident. As Svea Rautenberg, GIS Developer at BGS points out, “The ArcGIS app lowers the barriers to accessing spatial data on mine gas risks and makes it far easier for users from all backgrounds to make well-informed decisions to improve public safety.”

A template solution for other mining areas
BGS plans to continue to develop its pioneering coal mine gas risk decision-support tool, which is believed to be the first of its kind in the world. It hopes to make similar tools or services available to local authorities in other mining areas in the future. Summing up, Beriro says, “BGS is a non-departmental government body and part of the Department of Science, Innovation and Technology. We are a leading and trusted provider of geological data and knowledge to meet the societal need for a sustainable future. With this ArcGIS project, we are fullfilling our remit by enabling councils to make faster decisions, supporting improved public health and helping to deliver more housing in the UK using data-driven geoscience.”