Self- Potential (SP) geophysical surveys measure the potential difference between two points on the ground produced by the small, naturally produced currents that occur beneath the Earth's surface. It is predominantly used for DSEAR risk assessments at new petrol stations.
The SP method is passive, non-intrusive and does not require the application of an electric current. Small potentials of a few millivolts produce two electrolytic solutions of differing concentrations that are in direct contact. Followed by the flow of groundwater through porous materials (streaming potential). Larger ground potentials are generated by conductive mineralised ore bodies which are partially immersed below the water table.
Passive measurement of ground potential using the Self-Potential method
Typical applications
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DSEAR stray current testing
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Finding leaks in canal embankments
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Identifying seepage in dams and reservoirs
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Assessing effectiveness of water-engineering remedial measures
Above : Passive measurement of ground potential using the SP method.
Self - Potential Survey Operation
Standard Self-Potential surveys utilise non-polarising, porous pot electrodes. They have been adapted to minimise contact voltages. Readings are typically taken with one electrode fixed at a base station. A second, mobile 'field' electrode is moved around the survey area. Reading stations are spaced at regular intervals along linear profiles, closed loops or grids depending upon the desired application.
Stray Current Testing
Self-Potential is a useful method for detecting sporadic, man-made electrical currents in the ground, known as stray currents. These are produced by faults in high voltage electrical plant. For example, generators, industrial machinery and sub-stations. The resultant changes to the natural electrical field are dynamic and random in nature. They can result in a potential hazard in some circumstances. Stray currents cause localised, enhanced corrosion of buried steel structures. In rare circumstances they can create an ignition risk around buried fuel tanks and fuel pipelines. Our customised SP equipment can detect random changes to the background electric field vector. This makes it a valuable tool for carrying out DSEAR risk assessments at new petrol stations and other sites where volatiles are to be stored in Underground Storage Tanks (USTs).
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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.
Survey Methodologies
Detailed Magnetic Survey
Soil Self-Potential
Electrical Resistivity Tomography (ERT)
Soil Thermal-Resistivity Testing
Electromagnetic Ground Conductivity
Electromagnetic Location (EML)
Ground Penetrating Radar (GPR)
