Playing Hard to Get
LandScope was recently tasked with locating a 9″ Asbestos Cement Pipe across two adjacent fields. Electromagnetic Location would not be capable of detecting the non-magnetic pipe and as such, it was determined that Ground Penetrating Radar would be the best approach. LandScope opted to use its Leica DS2000 dual frequency system since the combination of 700MHz and 250MHz antennas would provide excellent data resolution as well as depth of signal penetration.
The detection and mapping of non-metallic pipelines, at depth, across open agricultural fields is rather challenging. The classic hyperbolic response is often masked and the geophysical surveyor must heed other clues such as the signal return from trench sides and floor, discontinuity in soil layering and associated use of anomalous back-fill material. Dry conditions and well drained soils certainly help. The challenge is to avoid any unnecessary trial holes and ensure the JCB driver is back home in good time for his tea.