There are estimated to be around 405,000 abandoned mine entries in the UK, of which only 150,000 are recorded. Approximately 15 mineshafts collapse each year and with so many unrecorded shafts, mines can have a huge and unexpected impact on future development projects.
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While some of these mineshafts have been simply abandoned, others have been capped and backfilled. Furthermore, mining records sometimes show the location of a suspected shaft, however the position is only approximate and there is often very little or no detail on whether the mine has been capped, let alone with what material.
A range of geophysics techniques can be used to find abandoned mineshafts, which rely on the different physical properties of the cap (if present) and the shaft. For example steel used in the cap, or from the cut-off anchors of the mine head gear, can be detected by magnetometry. Similarly, the presence of the mineshaft itself, whether backfilled or filled with air or water, would cause an anomaly in the electrical conductivity of the site, compared to the surrounding geology which a ground conductivity survey could identify. At the same time, the buried structural remains are likely to change the dielectric properties of the mineshaft itself, which ground probing radar could pick up.
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Ground Conductivity Survey
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An abandoned shaft infilled with different material to the surrounding in-situ ground can be detected by a Ground Conductivity Survey. The data is displayed as a contour plan, in which a mineshaft may appear as a small, discrete, high or low conductivity anomaly that stands out from the surrounding background.
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Detailed Magnetic Survey
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A magnetic survey can detect ferrous metal as well as soils, rocks and artefacts containing weakly magnetic minerals. A shaft that has been capped with iron or steel elements can be easily identified with this method, as can scrap metal which may have been dumped into the upper levels of a mineshaft.
Above : Ground conductivity data (left) and Magnetic data (right) showing a combined ground conductivity C1 and magnetic anomaly M1 close to a nominal mineshaft position (MS-5).
Ground Penetrating Radar Survey (GPR)
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A GPR survey can identify several things which may indicate the presence of a mineshaft. For example, a mineshaft capped by reinforced concrete can be detected as a discrete, buried reinforced concrete slab, whilst an uncapped shaft, or one capped with timber or other non-metallic materials may be identified by the presence of a large internal void. Similarly, if the shaft has been backfilled, then detection relies on the contrast between the backfilled material in the mineshaft and the surrounding in-situ ground.
GPR data can be displayed in plan and in section view as in the example below.
Above : GPR Radargram (section) showing possible mineshaft at c. 1m depth.
The selection of the appropriate Geophysical technique is often dependent upon the size of the survey area and the ground conditions present, as well as any information that is available about the shafts themselves. Certainly, the more techniques that can be deployed the better, as several targets found at the same location by different techniques will reinforce the confidence of the interpretation made.
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How accurate is SUMO's underground utility survey and what types of utilities can it locate?Using cutting-edge technologies like electro-magnetics, signal induced threading, and Ground-Penetrating Radar (GPR), our underground utility surveys accurately detect a wide array of buried utilities including metal and plastic pipes, drainage systems, electricity cables, telecoms, and fiber optic cables. The methodology ensures high accuracy without the need for invasive trial holes.
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What is the turnaround time for obtaining results with SUMO's Underground Utility Detection service?SUMO’s service is built for rapid response. Contractors can receive immediate results onsite. Our equipment provides real-time information, and once we leave the site, the detected utilities are visibly marked on the ground surface for quick reference.
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Does SUMO provide detailed mapping of the detected utilities for permanent records or construction purposes?Absolutely, SUMO not only marks the detected utilities on-site but also offers high-quality, color-coded survey drawings. These drawings can include topographic features and a comprehensive record of the utility detection survey, ensuring it meets the client’s needs for future reference or pre-construction design works.
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Topographical and Geophysical surveyIn addition to mapping out utilities, our experience team can accurately survey the land, creating topographical drawings for use. With our state-of-the-art aerial technology, nothing is missed.
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What additional information can be included in the underground utility mapping service provided by SUMO?In addition to topographic features, SUMO’s mapping service can include fixed surface utility features such as inspection chambers, valve boxes, and telegraph poles. It can also incorporate key topographic details like building lines, fence lines, kerb lines, street furniture, street names, building names, and house numbers, facilitating easy site location.
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Does the utility mapping service by SUMO include standard referencing and compatibility with existing survey data?Yes, SUMO ensures the utility mapping references the ordnance survey grid and level datum as standard. Additionally, the drawings can be supplied to a specified grid and level datum and can overlay an existing topographical survey, making it a versatile and adaptable service for various project needs.
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What sets SUMO Services apart from other survey providers?SUMO stands out due to our impeccable level of service with nationwide coverage, state-of-the-art equipment, and our commitment to delivering top-quality, detailed colour-coded survey drawings in both hard and electronic formats.
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How do I request a survey quotation from SUMO Services?Requesting a quotation is easy. Just click on the "Request a Survey Quotation" button on this page, and our team will get in touch with you promptly.
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Can I book a SUMO Survey online?Yes, you can! Simply click on the "Book a SUMO Survey" button on this page, and you can schedule your survey with us at your convenience.
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What type of survey is suitable for my project or site?Our experienced team will work with you to determine the most appropriate survey for your specific needs. Contact us, and we'll assist you in making the right choice.
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Can I obtain both digital and hard copies of survey drawings?Absolutely. We offer the convenience of electronic copies for digital use and hard copies for your records. Just let us know your preference.
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Do you provide custom survey solutions for unique projects?Yes, we understand that every project is unique. Our team is highly adaptable and can tailor our surveying services to meet your specific requirements.
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How do I get in touch with SUMO Services for further questions?For any additional questions or inquiries, feel free to contact us through the contact form, and our dedicated team will assist you promptly.
Geophysical Engineering Surveys
Air Raid Shelters
Cellars & Basements
Post Tension Cables
Underground Storage Tanks
Air Voids
Chimney Flues
Rebar
Water Engineering
Badger Setts
Earthing Installations
Sinkholes
Burials
Geological Application
Soil Thermal Resistivity Testing
Buried Foundations
Landfills
Structural Investigations
Buried Manholes
Mineshafts
