What Is Ground Penetrating Radar?
Ground Penetrating Radar (GPR) is the general term applied to techniques that employ radio waves, typically in the 1 to 1000 MHz frequency range, to map out structures and features below the surface. This technology is similar to that of a fish finder, as the GPR emits weak radio frequencies into the earth and detects the echoes sent back to build an image.
The GPR requires a relatively flat surface that runs flush with the ground, and a minimal scan run area of 3.0m (10 feet) is needed to complete an accurate scan of any given area. Uneven, raised surfaces with little run space for the GPR (ex. flower beds, landscaped areas or confined spaces) would be considered limitation factors and can cause inaccuracy in the imaging. The average radiated power from the radio waves emitted by the GPR are less than 1% of the transmitted power of a cell phone, making it safe for those around it during use.
Benefits of GPR Technology:
Ground Penetrating Radar (GPR) is now the locating tool of choice when it comes to detecting underground fuel storage tanks (USTs) on residential or commercial properties.
Magnetic detection is no longer as effective as a locating tool for USTs as many underground storage tanks have been rendered inert, in many cases the entire top half of the tank has been removed, which makes it almost impossible for the metal that still remains to be located via magnetic detection.
GPR is not influenced by metallic objects such as chain link fence, rebar in concrete, or buried construction metal waste, which can result in false positive readings in ferrous metal detection. Fiberglass tanks are also at risk of being missed with magnetic detectors, and the historic tank nests where previous fuel storage tanks were located. Ground penetrating radar provides a non-destructive, non-invasive and reliable geophysical investigation.