Pipelines near high-voltage AC lines face a corrosion risk standard CP design doesn't cover. Here's what AC mitigation under NACE SP21424 actually requires.

Two Ways to Push the Same Electrons Both systems do the same job: they turn the pipeline into the cathode in its own corrosion cell so the steel stops giving up electrons to the surrounding soil. The difference is where those electrons come from. A galvanic system relies on a more reactive metal — magnesium, zinc, or aluminum — that corrodes on purpose so the pipeline doesn't have to. An impressed current system (ICCP) uses an external DC power supply (a rectifier) to push cu

PHMSA has proposed the first major rewrite of federal pipeline repair standards in more than twenty years, and it's the kind of regulatory update that doesn't grab headlines but changes how integrity and CP data get used day to day.