Abstract
With the dependency on pipe-to-soil potential measurements for monitoring the effectiveness of cathodic protection systems, it is important to determine what portion of a pipe is "sampled" by an aboveground pipe-to-soil potential measurement. One important area which has not yet been investigated is the portion of pipe sampled during a potential survey of a pipeline in a right-of-way containing multiple pipelines bonded to each other. As continuous potential surveys become used more often for analyzing pipeline conditions and cathodic protection (CP) effectiveness, understanding what is being measured in a right-of-way containing multiple pipelines is required to improve the understanding of these surveys.
The overall objective of this project was to improve the ability to interpret close-interval on- and off-potential surveys in rights-of-way containing multiple pipelines. This objective was accomplished through a series of finite element computer models. Based on the work presented in this report, it was concluded that errors in ground level on- and off-potentials due to the interaction of two adjacent pipelines in the same right-of-way can be significant under certain conditions.
