Pipeline Safety Interpretation PI-81-0114

Page 1PI-81-0114 September 4, 1981 Mr. Mike Anderson Mechanical Engineer Intermountain Gas Company 555 South Cole Road P.O. Box 7698 Boise, Idaho 83767 Dear Mr. Anderson: Thank you for your letter of August 20, 1981 asking whether a building may be constructed over a cased natural gas main. The Federal safety standards for natural gas pipelines in 49 CFR Part 192 do not prohibit the operation of a cased main or other gas pipeline underneath a building. Therefore, as long as there is no State of local restriction, an operator of a gas pipeline may construct a building over it, and since Part 192 does not apply to persons other than operators, such persons may construct a building over a gas pipeline absent any State or local restriction. The regulations you refer to would not apply to the situation of a building being constructed over a cased main. Section 192.323, “Casing,” is a construction requirement that applies when a transmission line or main is being installed with a casing under an existing railroad or highway. Also, section 192.361 applies to service lines, not mains, and like section 192.323, it applies at the time the pipeline is under construction. Of course, an operator who has a pipeline over which a building is being constructed must, as required by section 192.613, take appropriate action in response to any changes in class location, corrosion control measures, or other unusual operating or maintenance conditions that the building would create. Sincerely, Original Sign By Melvin A. Judah Acting Associate Director for Pipeline Safety Regulation Materials Transportation Bureau#

Page 2Intermountain Gas Company 555 South Cole Road P.O. Box 7608 Boise, Idaho 83707 August 20, 1981 Department of Transportation 400 7th Street, S.W. Washington, D.C. 20590 RE: Desired Interpretation Dear Sir: We have presently a buried 4” steel coated and wrapped natural gas main that is cased in 6” steel and has a MAOP of 60psig (not a transmission pipeline). Can a building be constructed over this cased main? Our finding from CFR 192.361 and 192.323 is that it would be permitted with proper venting and maintenance procedures. Your opinion on this matter would be appreciated. Best Regards Mike Anderson Mechanical Engineer.#