Enbridge also underestimated the presence of "hard spots" in the pipeline according to the report. A hard spot is a point in a pipeline where metal is harder than the surrounding metal.

The 30-inch pipeline, owned and operated by Enbridge Inc., had a preexisting manufacturing defect known as a hard spot, the agency said. That combined with a degraded pipeline coating and ...

The deadly 2019 rupture of a natural-gas pipeline in Kentucky happened because of factors that included a manufacturing defect in the metal of the pipe and ineffective protection against corrosion ...