Tennessee Public Service Commission — Pipeline Safety Interpretation

Page 1July 2, 1975 Mr. John Searcy Engineering Division Tennessee Public Service Commission Cordell Hull Building Nashville, Tennessee 37219 Dear Mr. Searcy: This refers to your letter of June 19, 1975, transmitting a letter petition for waiver from compliance with 49 CFR 192.455(a) by the Memphis Light, Gas and Water Division as to facilities apparently within the Commission's jurisdiction. Because of the unique Federal and State relationship under the Natural Gas Pipeline Safety Act of 1968, a petition for waiver regarding intrastate gas pipeline facilities under the jurisdiction of a State agency that has in effect a certification under §5(a) of the Act is properly submitted to that State agency. While §3(c) of the Act provides that the Secretary of Transportation finally determines whether the requested waiver may be granted, the Act is clear that the State agency, and not the Secretary, decides initially whether to grant or deny the waiver request. Thus, the letter of petition is returned herewith. Sincerely, \signed\ Joseph C. Caldwell Director Office of Pipeline Safety Enclosure dal\192\455\75-07-02 1#

Page 2TENNESSEE PUBLIC SERVICE COMMISSION June 19, 1975 Mr. Joseph Caldwell Department of Transportation Office of Pipeline Safety 2100 Second Street, SW Washington, D.C. 20590 Dear Mr. Caldwell: The sentence in Section 3(e) of Public Law 90-481 reading "A State agency...may waive compliance..." (emphasis this writer's) is permissive rather than mandatory, and we elect to have you determine waiver requests. Accordingly, we submit the enclosed waiver request from Memphis Light, Gas and Water Division. Sincerely, \signed\ John Searcy, Engineer Engineering Division Enclosure dal\192\455\75-07-02 2#

Page 3MEMPHIS LIGHT, GAS AND WATER DIVISION June 17, 1975 Tennessee Public Service Commission Cordell Hull Building Nashville, TN 37219 Gentlemen: Section 3(e) of the Natural Gas Pipeline Safety Act of 1968 authorizes any state agency certified under Section 5(a) to waive compliance with any standard if the agency determines that the waiver is not inconsistent with gas pipeline safety. The Memphis Light, Gas and Water Division hereby requests a deviation from the requirements of Part 192.455(a) of Subpart I to permit components of pipeline fittings constructed of type 316 stainless steel to be installed without coating and/or cathodic protection. Memphis Light, Gas and Water Division proposes to use type 316 stainless steel components for the applications listed below: (a) Components of primarily plastic fittings used for transition of plastic to plastic in direct burial applications. (b) Components of fittings used for transition from plastic to copper inside a conduit used as a service riser (see attached copy of MLGW's Construction Standard 245.72). dal\192\455\75-07-02 3#

Page 4(c) Components of plastic fittings used for service tapping tees (see attached copy of MLGW's construction Standard 245.51). We believe that a precedent was set when Southern California Gas Company was granted a waiver in October, 1973. We are confident that the use of fittings with type 316 stainless components without coating or cathodic protection is not inconsistent with pipeline safety. It is not economically feasible to coat and cathodically protect the fitting components identified above and it would be an economic hardship to use carbon steel components with coating and cathodic protection, and thereafter perpetually monitor the large number required each year. Therefore, the Memphis Light, Gas and Water Division respectfully requests this deviation from Part 192.455(a) of Subpart I of the OPS Requirements for Corrosion Control. Very truly yours, \signed\ Ira C. Stanfill Director, Gas Division Enclosures dal\192\455\75-07-02 4#