This is an onsite survey using Radio Frequency Detection (EML) and Ground Penetrating Radar (GPR) to physically trace and map buried services and utilities.

This is completed by:

1. Investigating manholes, inspection chambers, valves, gullies, and other access points to induce a radio frequency signal directly into the service (or threader for drainage/ductwork) using a transmitter box. The signal is then traced at ground level using a receiver, and the route, depth and position of the buried service are marked onto the ground surface in spray paint.
   
   
2. The site is surveyed using passive radio frequency sweeps over a grid formation to identify any other conductive and metallic services, with their routes again marked on the ground in spray paint.
   
   
3. We then mark out an orthogonal grid and push a ground penetrating radar (GPR) system along it, collecting data as we go. This will confirm findings we already have, as well as identify other services that have not yet been detected, such as drainage, ductwork, plastic gas and plastic water.
   
   
4. These marks, together with the radar grid, are topographically recorded using an EDM alongside other hard features such as building lines, changes in surface, kerbs and boundary lines.

To meet your obligations under HSG47 and identify the locations of buried services and utilities which need avoiding, protecting or diverting. Many clients commission our services at design stage so that projects are planned in conjunction with the existing onsite buried services and utilities.

We use Radio Frequency Detection (Electro-magnetic Locating) and Ground Penetrating Radar (GPR), with topographical survey disciplines to record our findings.

We would look to locate the position, depth and, where possible, utility type for any buried services and utilities, regardless of the material of construction, and to includ,e for example, plastic pipes, fibre optic cables and ducts, communications and conductive services.

Our standard deliverable is an AutoCAD DWG file and an accompanying 2D plan view PDF output.

We can also provide an accompanying Manhole Schedule and Report, subject to the type of survey requested.

If specifically requested, we do offer CCTV surveying alongside our usual output.

In general, a utility mapping survey has a 10% tolerance in either direction, in reference to the depth of any given service. For example, a utility identified as 1m in depth will have a tolerance of 100mm in any direction.  Once the threshold of the survey exceeds 2m below the ground surface, these tolerances can increase exponentially.

Some services may not be located due to many reasons and factors.

Yes, we work extensively to PAS128. This standard outlines the optimum methodology required for different types of sites and environments to achieve the best possible survey results.

GEOTEC operates nationwide, covering England, Wales, Scotland, Northern Ireland and Eire.