GPR, or Ground Penetrating Radar, is an integral part of our suite of buried services location techniques.
We have two GPR units – a Mala Easy Locator and a dual-antenna IDS unit.
GPR operates by transmitting pulses of high-frequency radio waves into the ground in order to map both metallic and non-metallic sub-surface plant, and other structures and features. The radio waves reflect off buried objects or boundaries, which have an abrupt change in electrical properties, and are presented as a radiogram for the operator to interpret. The maximum depth at which GPR can detect a service depends on a number of factors, including the size of the object to be located (the deeper a service, the larger it must be) and ground conditions (dry, sandy soils are better than wet, salty clays).
GPR is used in two main modes. It can be used ad-hoc to mark out services as they are discovered, or a critical area (typically a highway, or other limited-access site) can be systematically scanned in a full-coverage grid and the data post-processed and analysed with specialist software.
GPR is also of use in building and engineering survey contexts to locate voids and other items of interest other than services, including underground tanks and natural ground features.