The advantages of GPR are simple. It is an accurate, rapid and high-resolution technique, which is non-invasive, non-destructive and completely safe. As opposed to other locating techniques, which are capable of detecting only metallic/conductive utilities and underground targets, GPR is the only non-intrusive technique capable of accurately locating non-metallic subsurface features and utilities (eg. clay or concrete piping, fiberglass fuel lines, PVC conduit or pipe and fiber-optic cables). In addition GPR can accurately map layer thickness and the depth to buried objects or cavities. The equipment can be mounted on a trolley for pavement surveying, on a vehicle for road/land surveying or it can be hand-held.

Construction/Engineering

General site investigation

• GPR is a non-destructive, reconnaissance tool for general sub-surface mapping (soil/rock horizons, depth to water table etc.) and buried object location prior to invasive investigation.
• GPR can assist in the planning and location of follow-up intrusive sampling programs (trial pits, boreholes, coring).
  

Utility Detection & Mapping (depth, position and direction)

• Detection and mapping of buried structures such as plastic water and gas pipes, fibre optic ducts, concrete sewers, clay drainage and asbestos cement pipes as well as the standard traceable services, made of steel, cast iron and power carrying cables.
• Subsurface piping leak detection and leak impact assessment (presence of washouts or voids)
  

Concrete Non Destructive Testing

• Identification and location of embedded structures (metallic and non-metallic conduits, rebars and tension cables) within concrete structures (e.g., bridges, dams, reservoirs, foundations, tunnels, runways etc.).
• Identification and location of voids and zones of construction degradation (concrete layer thickness and water content)
• Quality Assurance Control of new structures or existing constructions for rehabilitation purposes
  

Road & Rail Investigation

• Mapping structure of asphalt and concrete pavement, (layer thickness, layer integrity, water content, voids) for effective maintenance and rehabilitation decisions
• Map railroad ballast thickness.
• Identification of embedded utilities

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Environmental

• Landfill delineation
• Brown Field Site Investigation: mapping of existing services, thickness of made up ground, unknown cellars, voids and buried objects prior to excavation.
• Contaminant Plume profiling (from tank leaks, surface spills, piping leaks, landfills)
• Soil stratigraphy mapping (soil condition, compaction and water distribution)
• Underground storage tank (UST) location (steel, concrete or fiberglass)
• Underground Storage Drums location

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Archaeological/Forensics

• General sub-surface investigation of ground conditions and target location around archaeological and forensic sites.
• Location of buried objects and buried remains or disturbed soil associated with a burial.
• Location and delineation of buried objects, walls & foundations, soil disturbances and hidden cavities.

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Geological & Mining Applications

• General subsurface mapping (rock quality, fault and fracture detection, soil stratigraphy, depth to bedrock)
• Subsidence and swallow hole investigations, karst mapping.
• Soil & aggregate mapping (soil composition and compaction aggregate depth, quality & quantity)
• Water resources (water table delineations, soil water distribution)
• Quarry and mine mapping (tunnelling, rock mass stability, mineral and ore zone delineation)

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Financial and Insurance Institutions

• Property assessment (building integrity/construction quality control).
• Risk assessment.
  

Limitations

• As with any other geophysical technique, GPR is extremely good in some circumstances and should not be used at some locations.
• GPR anomalies rely on a detectable contrast of subsurface electrical properties between two media or within a medium. In the absence of a detectable contrast, no anomaly will be evident. It is possible that ground conditions may contain targets that are absent from the GPR data. Also, GPR data can contain weak anomalies, which are difficult to interpret.
• GPR signal cannot penetrate highly conductive material e.g., beneath metal sheets or very wet ground.
• Calibration should be carried out to obtain accurate depth estimates.
• GPR data processing and interpretation can be complicated - specialised analysis and interpretation is required.
• GPR is unsuited to absolute measurement, e.g., it can find wet areas, but at the moment cannot determine actual moisture content (currently under research).
• GPR is an interpretive method, based on the identification of reflectors, which may not uniquely identify an object.
  

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