Sierra Pacific Power Company — Pipeline Safety Interpretation

Page 111/10/98 Mr. Michael G. Rodriguez Supervisor, Gas System Control Sierra Pacific Power Company PO Box 10100 Reno, NV 89520-0024 Dear Mr. Rodriguez: I am responding to your letter of September 28, 1998, to Tom Lael concerning the requirements of 49 CFR 192.195 for overpressure protection at city gate stations. Specifically, you asked if an LDC that receives gas at four regulating stations operated by a transmission company is required to provide overpressure protection at each station in addition to the station’ s working and monitor regulators. Each station reduces the pressure of gas delivered to the LDC from 540 psig to 90 psig, the maximum allowable operating pressure (MAOP) of the distribution system. Each distribution system to which §192.195 applies that is connected to a gas source that has higher pressure than the MAOP of the system must have certain overpressure protection devices. If an LDC seeks to satisfy this requirement by relying on overpressure protection devices operated by its gas supplier, the LDC is still responsible for compliance with §192.195. In your situation, if the devices at each of the transmission company’ s regulating stations comply with §192.195 requirements, then no other protective devices are necessary. If we can be of further assistance, please call me at (202)366-4565. Sincerely, Richard D. Huriaux, P.E. Regulations Manager Office of Pipeline Safety LMFurrow:jmd:64046:10-21-98 cc: DPS-1,20,Regions,TSI,StateMailing#