Enhanced Inspection of Buried Pipelines Subjected to Electromagnetic Interference from Transmission Power Lines and External Cathodic Protection System

Using the combined CIPS-DCVG (Close Interval Potential Survey)-(Direct Current Gradient Potential) technique provides data on the cathodic protection system's potential and information about possible defects in the pipeline coating. The great advantage of the combined inspection is that both techniques are performed simultaneously under the same climatic and soil conditions, eliminating spatial error. However, in order to properly assess the integrity of the pipeline, the data provided by the combined technique must be accurate. In regions with electromagnetic interference, the quality of the data collected in the field may be compromised. This study demonstrates through a practical example that the effects of electromagnetic interference on data collected in the CIPS-DCVG survey can be mitigated by using GPS-synchronised stationary data loggers at gas pipeline cathodic protection system measurement points.