NTSB Safety Recommendation Letter P-76-065 through P-76-066

Page 1Official PDFa WASHINGTON, D.C. I S S U E D : August 11, 1976 M r . W i l l i a m T. Coleman, Jr. Secretary Department of Transportation Washington, D. C. 20590 SAFETY RECOMMENDAT ION(S) P-76-65 and 66 A t 7 : 5 2 a.m. on March 23, 1976, a 1,000-gallon liquefied petro- leum gas (LPG) tank owned by Lehigh U t i l i t i e s , Inc., ruptured i n a r e s i d e n t i a l neighborhood of Lehigh Acres, Florida. Liquid and vapors escaped from t h e ruptures. The escaping l i q u i d vaporized, formed a white, fog-like cloud near t h e ground, and ignited. The ensuing fire and explosion k i l l e d one person, destroyed one truck, and damaged another. The Safety Board's investigation disclosed t h a t a truck had backed over t h e buried LPG tank and had struck t h e t a n k ' s manhole, which extended 1 2 t o 1 4 inches above ground l e v e l . The impact rup- tured the tank's f i l l pipe, its r e l i e f valve, and i t s liquid-level gauge. The tank was p a r t of a pipeline system which was i n s t a l l e d i n December 1972 t o supply gas t o a r e s i d e n t i a l neighborhood which w a s being developed by t h e gas system's parent company, Lehigh Acres Development, Inc. The system incorporated two buried 1,000-gallon LPG tanks a t each end of t h e pipeline, which extended three blocks. Although vehicles were driven over the undeveloped l o t s to unload construction materials, the locations of t h e LPG tanks and the pipe- l i n e were not marked o r protected from t h e vehicles. Had t h e pipeline not crossed a public road, the system would not have been subject t o 49 CFR 192, because it served only two customers, and LPG systems which serve less than 10 customers a r e exempt unless a portion of the system is located i n a public place. However, had t h i s system transported natural gas, t h e system would have been subject t o the regulation regardless of t h e number of customers served. This exemption appears t o be u n j u s t i f i e d from t h e standpoint of protection of the public-at-risk. 1870#

Page 2The tank ruptured a t t h e juncture of t h e relief valve and ffl f i l l pipe, a t t h e juncture of the f i l l pipe and t h e tank, and a t juncture of t h e liquid-level gauge and t h e tank. The L.P. Gas Division of t h e S t a t e of Florida's Insurance Commission, which is responsible f o r determining compliance with the provisions of 49 CFR 192 by LPG operators i n Florida, i n t e r p r e t s 49 CFR 192.11 t o include a l l f a c i l - i t i e s of t h e p i p e l i n e system, including tanks, whereas the Office of Pipeline Safety Operations (OPSO) of t h e Department of Transportation has n o t determined whether OPSO has j u r i s d i c t i o n over LPG tanks which are connected t o p i p e l i n e systems. The f a c t t h a t OPSO has not deter- mined whether it has j u r i s d i c t i o n over LPG tanks might be detrimental t o t h e s a f e t y of persons who l i v e adjacent t o these systems s i n c e operators of t h e systems may be unsure whether 49 CFR 192 applies t h e i r systems. The impact of this problem is g r e a t since there are hundreds of such systems i n Florida and thousands i n the Nation. Therefore, the National Transportation Safety Board t h a t t h e Office of Pipeline Safety Operations of t h e Department of Transportation : C l a r i f y its j u r i s d i c t i o n with respect t o LPG tanks which a r e connected t o a p i p e l i n e system t h a t trans- p o r t s LPG vapor. (?-76-55) ( C l a s s 11, P r i o r i t y Followup) Modify the exemption from 49 CFR 192 f o r pipelines with less than 10 customers t o include systems t h a t have pipeline f a c i l i t i e s which expose a s u b s t a n t i a l part of a community or neighborhood t o a p o t e n t i a l hazard. (P-76-66) ( C l a s s 11, Priority,Followup) TODD, Chairman, BAILEY, Vice-chairman, McADAMS, HOGUE, a Members, concurred i n t h e above recommenffations. By: Webster B. Todd, Jr. Chairman NATIONAL IRANSPORIAIION SAFEI'Y BOARD WASHINGION D C 205'11 OFFICIAL nUS1NESS P E N A L I Y FOR PRIVAIE USE. a300 ?ihrlON,lG TndNSPOnTATlON Y~TETY nomD#