COAL MINING RISK ASSESSMENTS
COAL MINING RISK ASSESSMENT & Ground Stabilisation
The Coal Authority have established Coal Mining Development in England, Scotland and Wales with specific requirements for planning applications.
The Coal Authority is a statutory consultee for any planning application within a High-Risk Area. If your site is in a Development High Risk Area, you are required to submit a Coal Mining Risk Assessment to your Local Planning Authority High Risk Areas are typically areas of known historical mining recorded by the Coal Authority where pillars of coal may have been left in place to hold up the roof of the mine. Once the mine is abandoned the shallow mine workings have the potential to collapse.
NX geotechnical engineers carry out Coal Mining Risk Assessments for commercial, residential and industrial properties which include an assessment of the Coal Authority Mining Report, a visit to the offices of the Coal Authority to assess mining plans, a review of modern and historical published geological maps and review of technical reports/memoirs.
Large parts of the UK are within former mining areas with the potential to cause ground instability. When coal mining is present at shallow depth there is potential for settlement of structures should any remaining voids collapse.
Mine shafts also present a hazard from collapse which can destabilise the surrounding ground and structures and also be a preferable pathway for mine gas.
Rotary boreholes are used to explore potential shallow mine workings by drilling through bedrock and record resultant voids and deformation. Dependent on the sensitivity of the site and surrounding area, sentinel gas monitoring wells may need to be installed and monitored to assess the risks from mine gases.
Drilling and grouting techniques involves drilling holes to just below the level of the old mine workings and injection of grout (a mixture of PFA and/or sand and cement) to consolidate the old mine workings to reduce the risk of collapse and ground instability.
NX have expert engineers who can manage investigate and provide robust specifications for consolidation of shallow mine workings through drilling and grouting techniques.