APPENDIX E (continued)
before August 1, 1971.
(a) Except for buried piping at compressor, regulator, and
measuring stations, each buried or submerged transmission line installed
before August 1, 1971, that has an effective external coating must be
cathodically protected along the entire area that is effectively coated, in
accordance with this subpart. For the purposes of this subpart, a pipeline
does not have an effective external coating if its cathodic protection current
requirements are substantially the same as if it were bare. The operator
shall make tests to determine the cathodic protection current requirements.
(b) Except for cast iron or ductile iron, each of the following
buried or submerged pipelines installed before August 1, 1971, must be
cathodically protected in accordance with this subpart in areas in which
active corrosion is found:
Bare or ineffectively coated transmission lines.
(2) Bare or coated pipes at compressor, regulator, and
(3) Bare or coated distribution lines. The operator shall
determine the areas of active corrosion by electrical survey, or where
electrical survey is impractical, by the study of corrosion and leak history
records, by leak detection survey, or by other means.
(c) For the purpose of this subpart, active corrosion means
continuing corrosion which, unless controlled, could result in a condition
that is detrimental to public safety.
[Amdt. 192-4, 36 FR 12302, June 30, 1971, as amended by Amdt. 192-33, 43 FR
39390, Sept. 5, 1978]
Whenever an operator has knowledge that any portion of a buried
pipeline is exposed, the exposed portion must be examined for evidence of
external corrosion if the pipe is bare, or if the coating is deteriorated.
external corrosion is found, remedial action must be taken to the extent
required by N 192.483 and the applicable paragraphs of NN 192.485,
192-487.487, or 192.489.
External corrosion control: Protective coating.
(a) Each external protective coating, whether conductive or
insulating, applied for the purpose of external corrosion control must: