When a foreign structure is located near a pipeline that is protected by CP, the structure might:

When discussing foreign structures located near pipelines protected by cathodic protection (CP), the correct answer highlights the phenomenon of stray current—specifically how these structures can inadvertently receive some cathodic protection via stray currents. When there is a nearby foreign structure, such as another pipeline or a metallic structure, it can become a path for stray current to flow, which may also provide some level of cathodic protection to that foreign structure.

The ability of the foreign structure to pick up stray current can lead to unintended consequences, such as interference with the pipeline’s CP effectiveness. If the foreign structure collects stray current, it can lead to a decrease in the effectiveness of the cathodic protection system for the pipeline, because the stray current might divert from the intended CP application, thereby reducing the overall protection level that the pipeline would receive.

Understanding this process is crucial for pipeline integrity and safety management, as it emphasizes the need to monitor the interaction between CP systems and nearby foreign structures to ensure the pipeline remains adequately protected against corrosion.