{"operation":"document","citation":"PI-76-033","title":"Transportation Safety Institute — Pipeline Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"1976-06-23","effective_on":null,"summary":"PI-76-033 response to Transportation Safety Institute concerning 192.457.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-76-033.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-76-033.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-76-033","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/Pipeline/1976/PI76033.pdf","body":"<<<PAGE 1>>>\n\nJune 23, 1976\nMr. Edward J. Ondak\nProgram Manager\nTransportation Safety Institute\n6500 South MacArthur Boulevard\nOklahoma City, Oklahoma 73125\nDear Mr. Ondak:\nThis responds to your memorandum dated May 24, 1976, in which you asked for a decision\nconcerning the technique of using soil resistivity alone as an electrical survey to determine the\nareas of active corrosion.\nEnclosed is a copy of OPSO Advisory Bulletin No. 76-2, that contains the official OPSO\ninterpretation of the term \"electrical survey.\" Although areas of active corrosion have been\nshown to correlate highly with soil resistivity, this technique by itself does not fully meet the\nrequirements as set forth in the above interpretation. While the Office of Pipeline Safety\nOperations permits the use of consultants, it is the operator's responsibility to choose the\nmethodology to meet the requirements of the Federal safety standards.\nWe trust that this clarifies what OPSO expects in the way of compliance.\nSincerely,\nCesar DeLeon\nActing Director\nOffice of Pipeline\nSafety Operations\nEnclosure\ndal\\192\\457\\76-06-23\n1\n\n<<<PAGE 2>>>\n\nMEMORANDUM\nMay 24, 1976\nSUBJECT: Soil Resistivity as Electrical Survey\nto Determine Active Corrosion\nFROM : Program Manager, Pipeline Safety,\nTransportation Safety Institute\nTO : Acting Director, Office of Pipeline Safety\nOperations, MTP-1\nAt the 1976 Underground Corrosion Short Course held at the University of West\nVirginia, a discussion was held with members of the Harco Corporation, a well-\nknown corrosion consulting firm. At that time Harco stated that they presented a\nprogram to the Office of Pipeline Safety, as it was then known, in December of\n1973, in which they outline two methods to evaluate corrosion activity on bare\npipelines.\nThe March 1974 Advisory Bulletin stated that \"a technique was being used called a\nstatistical analysis to determine areas of active corrosion. This method combines\npipe to soil potential, soil resistivity, and leak records.\" The key word here was\n\"combines\" which means that more than one of the above mentioned techniques\nmust be used.\nHarco Corporation is attempting to utilize a survey consisting solely of soil\nresistivity. Their method states a probability combined with soil resistivity where a\nsection of pipeline lies in low resistivity soil versus a pipeline in high resistivity soil.\nThey then say that the probability of corrosion is greater for the pipe in low soil\nthan in high soil and they will therefore protect the low soil pipe first by August 1,\n1976, completely ignoring the pipe in high soil until some later date.\ndal\\192\\457\\76-06-23\n2\n\n<<<PAGE 3>>>\n\nI don't feel the intent of the law is being met as soil resistivity alone does not\ndetermine areas of active corrosion. If a pipeline is under cathodic protection, the\nsoil resistivity does not change. I have been chastised by Harco Corporation for\nmaking the above statement as they say OPS approved this technique. I maintain\nthat OPS did not approve this, as it was not stated in the Advisory Bulletin of\nMarch 1974.\nI am requesting that this matter by investigated and a decision made concerning\nthis technique. My biggest concern is the possibility that operators will get hold of\nthis and begin taking soil resistivity alone. This can never determine active\ncorrosion, only the possibility that corrosion might occur. This would never\ncomply with interpretations brought out by OPSO defining corrosion and how to\nfind it.\nPlease let me have your thinking on the above so we can better advise operators\nand State agents on proper techniques.\nEdward J. Ondak\ndal\\192\\457\\76-06-23\n3\n\n<<<PAGE 4>>>\n\nNovember 5, 1975\nMr. Cesar DeLeon, Acting Director\nOffice of Pipeline Safety\nDepartment of Transportation\n400 7th Street, S.W.\nTranspoint TES 30 Building\nWashington, D.C. 20590\nDear Mr. DeLeon:\nAt our recent meeting in Washington you commented that I had not submitted a question\nfor sometime. Unfortunately all matters have not been totally resolved and I will, therefore,\nappreciate an official answer to the following question:\nHow often must individual anodes be monitored on an unprotected bare transmission or\ndistribution pipeline that has \"hot spot\" protection, which \"hot spot\" protection would include the\nanodes installed in connection with corrosion-leak repair clamps?\nYours very truly,\nT. K. Spalding, Director\nGas Pipeline Safety Division\ndal\\192\\457\\76-06-23\n4","truncated":false,"body_characters":4413}