What are shallow mine workings?
Across the former coalfield areas of the United Kingdom shallow mine workings represent a problematic legacy left behind from the extraction of the coal. Typically, pillars of coal were left in place to hold up the roof of the mine.
Once the mine was abandoned these shallow mine workings have the potential to collapse at any time. If this occurs under or near a structure it can cause mining induced subsidence of sufficient magnitude to require complete demolition of the structure.
How would I know if I had a shallow mine workings problem?
Local Authority planners are required to consider the ‘safe and stable’ nature of a site as part of the
A range of data sources are available to help identify if you might have a problem including an on-line Coal Authority interactive map viewer.
In most cases where shallow mining is suspected the planners will require a mining risk assessment to be undertaken by a Consulting
Engineer; this will most likely include rotary boreholes.
If the assessment identifies shallow mine workings and these are considered to represent a risk, then the developer will be required to undertake some form of remedial action.
What can be done to rectify a shallow mine workings problem?
Normally this will be the consolidation of the shallow mine workings through drilling and grouting.
Drilling and grouting involves drilling holes to just below the level of the old mine workings, placing a liner in the boreholes, through soil (and rock) to keep the hole open, and injection of grout (a mixture of PFA and cement) to consolidate the old mine workings so that they can no longer collapse.
The spacing's of the holes and the grout mix can be altered to suit the site conditions or the purpose of the work.
Why use Groundshire?
Groundshire are a family owned and operated company. Drilling and grouting is our primary business, it is what we do and what we are good at.
We offer a range of services to our clients and our prospective clients that few of our competitors can match. We are approachable and we are prepared to offer advice free from obligation.
Across the Durham and Northumberland coalfields we have access to a huge collection of mining
maps that date back 150 years. These maps are often our first point of reference when determining
if there is likely to be an issue or not.
Although our key skills are in the treatment of mine workings, we are experienced professional
Engineers with relevant earth science degrees and with a detailed understanding of Geological and Engineering principles.
We carry Professional Indemnity insurance that allows us to design and implement our own works.
We at Groundshire have the expertise and experience to design appropriate treatment grids, which can often result in significant cost savings
In combination our knowledge of mining, geology and the planning process can provide you with a review of the land that you intend to purchase prior to sale that will prove invaluable in negotiation.
We provide this service from small single house plots to developments whose budgets are in the
tens of millions of pounds.
What do I get for my money?
Our designs are prepared by Specialist Engineers in line with the recommendations of CIRIA Publication C758, “Construction Over Abandoned Mine Workings”, as well as Coal Authority, NHBC and Local Authority planning requirements. These are backed by our Professional Indemnity Insurance.
Our works are carried out competently and to Industry Standard Specifications, our workmanship is backed by our Public and Products liability insurance. We provide completion reports for our projects that allow subsequent construction to be undertaken with complete confidence.
This is in line and above industry standards for all your insurance needs.
We will provide ongoing support if required.
What is the outcome?
The outcome is that the ground we have worked on is safe and stable and is suitable to build on.
We future proof your land.
Contact our team today for more information about our mine shaft solutions.