Subsurface Utility Engineering (SUE)
We have extensive experience providing Subsurface Utility Engineering (SUE). We utilize a number of techniques depending on the client’s accuracy requirements. Most projects with specific SUE requirements are performed at Quality Level A or B as defined in the CI/ASCE 38-02 standard. The standard also defines Quality Levels C and D which are limited to research and above-ground feature location as are typically provided as part of a topographic survey. Quality Level B SUE surveys require the use of surface geophysical methods.
We utilize a combination of pipe and cable locators along with ground penetrating radar (GPR) to accurately determine both the horizontal and vertical location of the target utilities. GPR can be used to locate and mark on the ground for subsequent field survey ties. For more detailed data, the area can be scanned in a grid pattern and post-processed to develop a 3 dimensional utility map for incorporation into the CADD or GIS survey files. We maintains state of the art SUE equipment including a Sensors and Software Noggin 250 SmartCart and 400 Series Digital Video Logger.
Ground Penetrating Radar (GPR)
Ground Penetrating Radar (GPR) systems are extremely accurate when it comes to locating metallic and non-metallic objects. GPR systems work by sending a tiny pulse of energy into the ground from an antenna. An integrated computer records the strength and time required for the return of reflected signals. Any subsurface variations, metallic or non-metallic, will cause signals to bounce back.
These reflections are produced by a variety of material such as geological structure differences and man-made objects like pipes and wires. When this occurs, all detected items are revealed on the computer screen in real-time as the GPR equipment moves along. Users can even tell from the signal returned whether the feature in question is metallic or non-metallic.