Virginia State Corporation Commission — Pipeline Safety Interpretation

Page 1PI-75-0113 November 17, 1975 Mr. John Baumgardner Engineer Virginia State Corporation Commission P. O. Box 1197 Richmond, Virginia 23209 Dear Mr. Baumgardner: This responds to your letter of November 7, 1975. We agree that if a regulator located in a vault is replaced without effecting a change in the vault, replacement of the regulator would not make the requirements of 49 CFR 192.187 concerning the design of vaults apply to the vault. Sincerely, SIGNED Cesar DeLeon Acting Director Office of Pipeline Safety Operations#

Page 2Commonwealth of Virginia State Corporation Commission Division of Public Utilities November 7, 1975 Mr. Cesar DeLeon Acting Director Office Of Pipeline Safety Operations Department of Transportation Material Trans. Bureau 400 7th Street, SW Washington, D. C. 20590 Dear Mr. DeLeon: We have recently had a question arise in regard to the requirement 192.187 for underground vaults. Specifically this pertains to those vaults containing pressure regulating stations constructed prior to the enactment of the code which have a volume in excess of 200 cubic feet. If a company upgrades a station by replacing the existing regulators along with the addition of the necessary controls (say if pilot operating regulators are to replace direct loading regulators) would 192.187 then apply to the vault containing the pressure regulating station? It is our contention that since the code lists the requirements for pressure regulating stations and vaults separately, and there has been no reconstruction or substantial change to the vault itself while upgrading the regulator station, then those requirements for vaults should not apply. However, we would appreciate an interpretation on this point, and if by chance the existing vaults would be subject to 192.187 under such circumstances, at what point in the replacement or regrading process would 192.187 then become applicable? We would appreciate your reply and if there are any further questions you may have, please advise. Yours truly, John Baumgardner Engineer#