Interpretation Response #PI-09-0014
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name:
Individual Name:
Country: US
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Response text:
August 18, 2009
Mr. K. G. (Kevan) McCrae
Environmental Coordinator
ExxonMobil Pipeline Company
800 Bell Street - (PL-EMB-603B)
Houston, TX 77002
Dear Mr. McCrae:
On January 30, 2009, you wrote to the Pipeline and Hazardous Materials Safety Administration (PHMSA) to request an interpretation of the corrosion control monitoring requirements in 49 CFR Part 195 of the Federal pipeline safety regulations that apply to your Portland to Bangor, Maine pipeline system. You stated that you are requesting an interpretation of § 195.567(a) which requires electrical test leads for monitoring the adequacy of corrosion control. As a result of an April 2008 inspection of the Portland to Bangor pipeline system, on July 28,2008, the PHMSA Eastern Region issued a warning letter to ExxonMobil Pipeline Company (EMPCo) for not following the requirements of § 195.567(a). The warning letter alleged that EMPCo committed a probable violation of § 195.567(a) by taking electrical readings directly from exposed piping in three specified locations rather than having test leads in place.
You expressed your disagreement with the interpretation reflected in the warning letter. You believe that test leads are only necessary when a pipeline and its appurtenances are not physically accessible to take cathodic protection readings. You stated that EMPCo's pipeline facilities are equipped with test leads where the pipelines and appurtenances are buried and inaccessible but not where pipe and appurtenances were accessible. You stated that the pipeline in question is 124.7 miles long and includes 95 total test points. Of the 95 test points, 17 pipe-to-soil readings are taken directly off the pipeline or its appurtenances and the remaining 78 pipe-to-soil readings are taken at test lead stations.
You further stated that: (1) you checked with other pipeline operators on this issue and all operators confirmed in taking direct readings where facilities are accessible on both gas and hazardous liquid pipelines as a standard industry practice; (2) EMPCo's previous and recent experience with PHMSA have not identified its cathodic protection survey procedures as inadequate; and (3) PHMSA's regulations governing natural gas pipeline corrosion control monitoring recognizes contact points other than test leads as legitimate (§ 192.469) and you believe there is no technical basis for treating a hazardous liquid pipeline differently. In addition, you provided an independent opinion letter by CC Technologies to support your assertion that taking pipe-to-soil readings where a pipeline is physically accessible is an acceptable practice.
Ensuring cathodic protection maintained at adequate levels is a key part of pipeline safety. Pipeline operators are obligated to install and maintain test leads at intervals frequent enough to obtain measurements indicating the adequacy of cathodic protection. To the extent readings sufficient to indicate the adequacy of cathodic protection at a particular location can be obtained from exposed pipe and appurtenances, it is unnecessary to install test leads at that point. Therefore, taking readings directly from exposed pipe that is physically accessible is not a violation of § 19S.S67(a). However, collecting cathodic protection readings directly from the pipe has the potential to compromise the protective coatings on the pipe, subjecting that exposed pipe to atmospheric corrosion. It is also important to recognize that test leads may be necessary for certain portions of buried pipeline facilities, even though they are in close proximity to exposed pipe.
I hope that this information is helpful to you. If I can further assist you with this or any other pipeline safety regulatory matter, please contact me at (202) 366-4046.
Sincerely,
John A. Gale,
Director, Office of Regulations