01Is your site at risk?
All land on the coalfield falls into either a Development High Risk Area or a Development Low Risk Area, set by the Mining Remediation Authority (formerly the Coal Authority). A high risk area has one or more recorded mining features at or near the surface, such as mine entries, recorded or probable shallow workings, or mine gas sites.
Risk is set site by site, not by town. Some Wigan postcodes sit in low risk areas with high risk areas close by, so always check the exact site. The MRA's interactive map is free to use, or send us the address and we will check it as part of your quote.
02Coal mining risk assessments and planning.
Most planning applications in a Development High Risk Area need a Coal Mining Risk Assessment, a site-specific report that identifies the mining features, assesses their risk and sets out any investigation and mitigation. A coal mining search bought for a property purchase is not a substitute.
Householder applications, such as most extensions, are exempt from the automatic requirement, although the council or building control can still ask. Our guide do I need a coal mining risk assessment? explains more.
03How we investigate.
Where an assessment recommends it, we drill rotary boreholes to prove the seams of concern and how much sound rock lies above them. The driller records signs such as flush loss or the rods dropping, which point to voids or broken ground, and rock core can be recovered where it is needed.
The drilling depth is set by the assessment or your engineer, and there is no single fixed depth.
Any intrusive work that enters or disturbs coal seams, coal mine workings or mine entries needs a permit from the Mining Remediation Authority. Standard permits can take 20 working days or more, so we build them into the programme from the start.
04Questions we get asked.
Is my site in a high risk area?
Check the address on the Mining Remediation Authority's interactive map, or send it to us and we will check it. The status is set site by site, not by town.
Do I need a coal mining risk assessment for my extension?
Householder applications are exempt from the automatic requirement, but the council or building control can still ask for one if they think it is needed.
Do you need a permit to drill on my site?
Only if the boreholes are expected to enter or disturb coal seams, workings or mine entries. We will tell you if your site needs one.
What is the difference between a mining report and a coal mining risk assessment?
A coal mining search is for buying a property. A coal mining risk assessment is a site-specific assessment for development, and a mining search should not be used to inform one.
