{"operation":"document","citation":"PI-77-0106","title":"Pipeline Safety Interpretation PI-77-0106","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"1977-06-27","effective_on":null,"summary":"PI-77-0106 concerning 192.755.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-77-0106.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-77-0106.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-77-0106","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/Pipeline/1977/g77-06-27_Heverly_192.755%20-%20lmxs.pdf","body":"<<<PAGE 1>>>\n\nPI-77-0106\nJune 27, 1977\nChief, Eastern Region, MTP-50-EA\nActing Director, Office of Pipeline\nSafety Operations\nAlternatives to Section 192.755\nYour memorandum of March 21, 1977, on this subject asks two separate but related questions about possible\nmethods of compliance with Section 192.755, \"Protecting cast-iron pipelines.\" This section is applicable where\nan existing buried pipeline is crossed by an earth excavation or ditch or is located in potentially unstable soil\ndue to an excavation being dug nearby and deeper than the gas pipeline.\nSection 192.755 requires When an operator has knowledge that the support for a segment of a buried cast-iron\npipeline is disturbed:\n(a) That segment of the pipeline must be protected, as necessary, against damage during the\ndisturbance by:\n(1) Vibrations from heavy construction equipment, trains, trucks, buses, or blasting;\n(2) Impact forces by vehicles;\n(3) Earth movement;\n(4) Apparent future excavations near the pipeline; or\n(5) Other foreseeable outside forces which may subject that segment of the pipeline to bending stress.\n(b) As soon as feasible, appropriate steps must be taken to provide permanent protection for the\ndisturbed segment from damage that might result from external loads, including compliance with\napplicable requirements of Sections 192.317(a), 192.319, and 192.361(b)-(d).\nFollowing are the questions submitted and OPSO's interpretations.\nQuestion: If an operator cuts a cast-iron pipe in two and installs a leak clamp at a point where the operator\nsuspects soil settlement as a result of excavation by others, can this be considered as a satisfactory alternative to\nthe requirements of Section 192.755?\nInterpretation: The cutting of the pipe and installation of the coupling would possibly be of some benefit by\nproviding flexibility. However, without providing other means of support, such as compacting the soil to an\nequivalent compaction as the original soil, supporting with a beam to undisturbed soil, or replacing the cast-iron\npipe across the area with steel pipe extending well into the undisturbed soil, the segment would not be protected\nto a degree sufficient to assure the safety of the installation.\nQuestion: In the case of a leak caused by cast-iron pipe breaking in two, can the installation of a leak clamp\nsuffice for the requirements of Section 192.755? Or, must the operator comply with the requirements of Section\n192.755 as well so as to protect the pipe segment that was excavated against possible subsequent bending stress\ndue to soil settlement?\n\n<<<PAGE 2>>>\n\nInterpretation: The installation of a leak clamp would be considered as adequate leak repair but it does not\nprovide protection against further soil settlement. As indicated above, measures must be taken to stop or\nminimize the soil movement or some degree of resistance must be provided in the structural strength of the\npiping system crossing the affected area of construction.\nMany operators have adopted a standard policy of replacing cast-iron pipe in this sort of a situation with steel\npipe and taking necessary measures to protect the steel pipe. Attached are copies of a standard procedure that is\nused by one company for such construction areas.\nCesar DeLeon, MTP-1\nAttachment\n\n<<<PAGE 3>>>\n\nUNITED STATES GOVERNMENT DEPARTMENT OF TRANSPORTATION\nMemorandum MATERIALS TRANSPORTATION BUREAU\nDATE: MAR 21 1977\nTO: Acting Director, MTP-1\nFROM: Chief, Eastern Region, MTP-50-EA\nSUBJECT: Alternative to §192.755(?)\nIf an operator cuts a cast iron pipe in two and installs a leak clamp at a point where the operator suspects soil settlement\nas a result of excavation by others, can this be considered as a satisfactory alternative to the requirements of §192.755?\nLikewise, in the case of a leak caused by cast iron pipe breaking in two, can the installation of a leak clamp suffice for the\nrequirements of §192.755? Or must the operator comply with the requirements of §192.755 as well so as to protect the\npipe segment that was excavated against possible subsequent bending stress due to soil settlement?\nLance F. Heverly","truncated":false,"body_characters":4106}