The Client had applied for planning permission for a residential development. The Local Planning Authority granted planning but included a planning condition requiring a Coal Mining Risk Assessment by suitably qualified persons.
We reviewed an intrusive investigation undertaken previously and completed a desk based Coal Mining Risk Assessment in accordance with the Coal Authority guidance which identified unrecorded shallow workings within the Seven Feet coal seam at less than 10m depth beneath the west of the site, and the same seam to be present at very shallow depth (within 3m of the surface) beneath the east of the site. We provided a risk management strategy for the development with options for mitigation of subsidence risks and risks from possible combustion of the very shallow coal.
Previous investigation identified mine workings up to 1.4m height in the 2.3m thick Seven Feet seam within 10m of the site surface and the potential for workings in the Deep Rider seam at greater depth. An outline strategy for stabilisation of the workings by drilling and grouting was prepared for the Client as part of our Coal Mining Risk Assessment – given the shallow depth of the workings, this included for the development infrastructure as well as the individual dwellings.
No mine entries were recorded within the site boundary, however, given the extensive history of workings within the Warwickshire Coalfield (dating from medieval times) and the shallow depth of the coal the potential for ‘bell pit’ workings was identified, which are seldom recorded.
The Client was advised of a suitable course of action to mitigate the risks of the workings.
This project was one of many we have undertaken in coalfields across the UK, using our decades of experience and good understanding of historical mining and mine workings to benefit the Client in understanding the risks associated with development in past mining areas, and facilitating progress within the planning regime.