Hello I’m Shauna a Geotechnical Engineer. As a consultant at Earth Environmental and Geotechnical I’m often asked about CMRA’s and what they involve. A CMRA is a Coal Mining Risk Assessment and will be required as part of your planning application if your development is in a high risk area.
Coal Mining Risk Assessments identify site specific coal mining risks and set out the proposed mitigation strategy to show that the site can be made safe and stable for the proposed development.
Whether you are constructing a single dwelling or a large strategic site we can provide the right advice and support to take your development forward.
What is a Low or High Risk Area?
Basically the coalfield is divided into two areas, referred to as
Development High Risk Area and
Development Low Risk Area:
The High Risk Area – approximately 15% of the coalfield, is where coal mining risks are present at shallow depths.
The Low Risk Area – approximately 85% of the coalfield, is where past coal mining activity has taken place at sufficient depth that it poses low risk to new developments.
Slide – What identifies an area as High Risk?
So what identifies an area as high risk?
High risk includes a wide range of features which could have an impact on your future development.
The area may have geological features like fissures or break lines,
Mine entires may be identified.
There could be surface hazards or coal seam outcrops.
In some situations pockets of mine gas may be present
So it is crucial to have a thorough understanding of the site and any potential risks for your development.
What’s involved in a Coal Risk Assessment?
Firstly a desk review will be completed looking at geological and historical data. Coal Authority records, and local/regional records can be analysed.
A visit to the offices of the Coal Authority to assess mining plans may be completed. Plus The British Geological Survey would be contacted to obtain any coal exploration, water well and site investigation borehole information.
At Earth Environmental we are rigorous in our analysis and detailed in our reports.
What happens next?
If your Coal Risk Assessment Report identifies any risks to future developments, we will highlight what further investigations are required. This would usually involve rotary boreholes at agreed depths. As a general rule, a minimum of three boreholes will be required to satisfy the Coal Authority.
Earth Environmental have a number of competent in-house staff who can assist developers at any stage of a project, from coal mining risk assessments and site investigations through to remediation works (e.g. drill and grouting).
Our experts can quickly prepare a Coal Mining Risk Assessment to support your planning application. You’ll find more information about our Coal Mining Risk Assessments by following the link below.