Searches User Guide: Non-natural ground stability
Infilled land
Infilling from historical mapping
Historical land uses identified from Ordnance Survey mapping that involved ground excavation at the surface. These features may or may not have been subsequently backfilled. This data has been extracted from Groundsure’s 1:10,000 and 1:10,560 scale Historical Land Use Database dating back to the 1840s and includes features such as engine pits, heaps, and tips.
Data update schedule: Variable
Non-coal mining areas
The potential for historical non-coal mining to have affected an area. The assessment is drawn from expert knowledge and literature in addition to the Digital Geological Map of Britain. Mineral commodities may be divided into seven general categories: vein minerals, chalk, oil shale, building stone, bedded ores, evaporites and ‘other’ commodities (including ball clay, jet, black marble, graphite and chert).
This data is categorised on a 5 tier scale:
|
Category |
Description |
|
A - sporadic underground mining of restricted extent |
Potential for difficult ground conditions are unlikely and localised and are at a level where they need not be considered. Presence of past underground mining is not known to have occurred. Areas are categorized on the basis that the rock types present are known to have been worked in other areas. Areas therefore have the potential for underground mining but there is little or no evidence of mining activity. |
|
B - localised small scale underground mining may have occurred |
Potential for difficult ground conditions are unlikely or localised and are at a level where they need not be considered. Presence of past underground mine workings may occur but workings of small limited extent. Rock types present could support small scale underground mining. All such occurrences are likely to be of minor localised extent and infrequent. |
|
C - small scale underground mining may have occurred; mine adits, shafts and tunnels may be present |
Potential for localised difficult ground conditions are at a level where they should be considered. Presence of past underground mine workings may be present. Underground mining is likely to have been of limited extent. |
|
D - underground mining is known or considered likely to have occurred within or close to the area |
Potential for difficult ground conditions are at a level where they should be considered. Presence of past underground mine workings are probable. These are areas known or suspected to contain underground mining for minerals and/or other materials. |
|
E - underground mining is known to have occurred within or very close to the area |
Potential for difficult ground conditions should be investigated. Potential for localised subsidence is at a level where it should be considered. Presence of past underground mine workings are known or suspected to contain underground workings for minerals and/or other materials, extent of workings are likely to be extensive. No consideration has been given to the effects of remediation and it may be necessary to check if any remediation has been carried out. |
It should be noted, that there is always the possibility of the existence of other sub-surface excavations, such as wells, cess pits, follies, air raid shelters/bunkers and other military structures etc. that could affect surface ground stability but which are outside the scope of this dataset.
Data source: British Geological Survey
Data update schedule: Quarterly
Mining cavities
Industry recognised national database of mining cavities. Degraded mines may result in hazardous subsidence (crown holes). Climatic conditions and water escape can also trigger subsidence over mine entrances and workings. The cavity data have been collected from a diverse range of sources such as published information (e.g. technical papers, cave and mine guides, books etc), unpublished information (e.g. library and museum archives, academic studies, consultant and contractor archives etc), district and county councils, British Geological Survey and many others. The database includes mines excavated for the extraction of non-ferrous metals (e.g. fluorite, calcite and barytes), rock (e.g. slate, chalk, limestone, oil-shale, fullers’ earth and non-coalfield fireclays), iron (non-coalfield) and evaporites (e.g. salt and gypsum).
Data update schedule: Annually
Coal mining areas
Areas, defined by The Coal Authority, which could be affected by past, current or future coal mining. A site could fall within the ‘Coal Reporting Area’ but not be directly affected by coal mining.
Data update schedule: Annually
Brine areas
The Cheshire Brine Compensation District indicates areas that may be affected by salt and brine extraction in Cheshire and where compensation would be available where damage from this mining has occurred. Damage from salt and brine mining can still occur outside this district, but no compensation will be available, nor will these areas be shown within this dataset.
Data update schedule: Variable
The above datasets are used in all Groundsure environmental reports
Other infilled land (used in Avista, GeoRisk and GeoRisk +)
Active landfill sites
These are records of landfill sites that are operational or are in official closure and aftercare programs. Depending on the nature of the waste these landfill sites have accepted, they may pose a risk of contamination (including from landfill gases). Active landfills can also cause nuisance problems due to noise, dust and odour. However, these effects should be minimised under the conditions of their operating licence.
Data source: Environment Agency
Data update schedule: Quarterly
Historical landfill (from Environment Agency records)
Known historical (closed) landfill sites (e.g. sites where there is no Pollution Prevention Control (PPC) permit or waste management licence currently in force). This includes sites that existed before the waste licensing regime and sites that have been licensed in the past but where a licence has been revoked, ceased to exist or surrendered and a certificate of completion has been issued. The boundary information will often include all of the land owned by the operating company and may not correspond to the area of fill.
Data update schedule: Quarterly
Historical landfill (from Local Authority and historical mapping records)
These are records of former areas of landfill. These areas of land may have been redeveloped for other uses since the landfill closed. Depending on the nature of the waste these landfill sites accept, they may still pose a risk of contamination (including from landfill gases). Former landfill sites can also cause issues with ground instability.
Data update schedule: Annually