Montana-Dakota Utilities Company — Pipeline Safety Interpretation

Page 1Mr. Tony J. Finneman Montana-Dakota Utilities Company 400 North Fourth Street Bismarck, North Dakota 58501 Dear Mr. Finneman: You have asked whether an operator who voluntarily places a cathodic protection system on a gas pipeline installed prior to August 1, 1971, with no evidence of active corrosion must provide a level of protection according to the criteria in Appendix D of Part 192. A corrosion mitigation measure that is provided as a general maintenance practice would result in these pipelines being considered "unprotected" for purposes of Section 192.463 and the 3-year reevaluation requirement of §192.465(e). The Appendix D criteria apply to cathodic protection that is provided to comply with regulations in Subpart I or Part 192. In determining whether the Federal regulations require cathodic protection in the scenario outlined in your letter, you should assure that your program properly addressed all the requirements of the regulations, such as using the definition of active corrosion under §192.457(c). Also, in determining whether the electrical survey required by §192.457(b)(3) and §192.465(e) is impractical, you must consider all factors that relate to the impracticality, including public safety, not just economics. Copies of related interpretations published in OPS Advisory Bulletins are enclosed for guidance in implementing your program. Sincerely, Richard L. Beam Director Office of Pipeline Safety NOTE: THIS LETTER BELONGS IN APPENDIX "D" DB C:\WP51\INTERPRT\192\755\89-03-31 1#