Interpretation Response #PI-79-032

Interpretation Response Details

SUBJECT: Interpretations

FROM: Chief, Eastern Region, DMT-15

TO: Associate Director, OPSR, DMT-30
THRU: Associate Director, OOE, DMT-10

In connection with a transmission pipeline that an operator has determined to be in a Class I area, is the operator required to make an electrical survey on such a line in accordance with §192.457(b)(1)?

It is apparent that the installation of cathodic protection devices would not be required per our definition of active corrosion, but it is not clear as to whether the electrical survey must be made.

Please advise at your earliest convenience.

Lance F. Heverly

Interpretation of Section 192.457(b)

Associate Director, OPSR, DMT-39

Chief, Eastern Region, DMT-16
THRU: Associate Director, OOE, DMT-10

In your memorandum of June 11, 1979, you ask if a transmission pipeline that has been determined to be in a Class I location must have an electrical survey made in accordance with Section 192.457(b)(1), even though it is apparent that cathodic protection would not have to be installed because of the definition of "active corrosion."

Section 192.457(b) requires, in pertinent part, that bare and ineffectively coated transmission lines installed before August 1, 1971, must be cathodically protected in areas in which active corrosion is found. Further, this section requires that "active corrosion" be determined by electrical survey, or where this method is impractical, by other means. "Active corrosion" is defined in Section 192.457(c) to mean continuing corrosion which, unless controlled, could result in a condition that is detrimental to public safety. Under these provisions, an operator must look for areas of continuing corrosion by electrical survey where such a survey is practical. The survey technique or other allowable method is an essential first step in compliance. Then in situations where continuing corrosion could at some foreseeable time (not more than 3 years since Section 192.455(c) would require a resurvey in that time) result in a condition that is detrimental to public safety, even though such a condition does not now exist, the area of continuing corrosion must be cathodically protected.

Although one might expect that a corrosion condition detrimental to public safety would be less likely to develop in a Class I location, nonetheless Class location is not considered under Section 192.457 in determining areas of active corrosion. Rather, an operator should consider the short and long range effect of corrosion on the pipeline, the proximity to people, and other factors relevant to assessing the potential harm to people or property of continuing corrosion. (See 41 FR 29128 July 15, 1978). An electrical survey or other allowable method must be used to provide information needed to make this judgement.

Cesar DeLeon

Regulation Sections