NTSB Safety Recommendation Letter P-76-022 through P-76-025

Page 1Official PDFTATIOM SAF WASHINGTON, D.C. FOR RELEASE: 6:30 P,M,, E,D,T,, JUNE 14, 1976 M r . Robert E . Thomas P r e s i d e n t Mid-America P i p e L i n e System 1437 S. Boulder Avenue T u l s a , Oklahoma 74119 SAFETY RECOMMENDAT I O N (5) P-76-22 through 25 A t 8:30 p.m. on February 25, 1976, a Mid-America P i p e L i n e System (MAPCO) 8-inch l i q u e r i e d petroleum g a s (LPG) p i p e l i n e r u p t u r e d n e a r W h i t h a r r a l , Texas. The e s c a p i n g LPG v a p o r i z e d , formed a low-lying cloud, and i g n i t e d . Flames r o a r e d skyward i n excess of 200 f e e t and engulfed a 3/4-mile-long by 1/4-mile- wide area. The f o r c e of the r u p t u r e c r e a t e d a crater 20 f e e t l o n g , 1 2 f e e t wide, and 5 f e e t deep. There were 5,415 b a r r e l s of LPG (227,430 g a l l o n s ) re- l e a s e d and burned. The occupants of two d w e l l i n g s i n the area were burned s e v e r e l y , and f i v e were k i l l e d . The flames receded toward t h e r u p t u r e d pipe- l i n e where they were e x t i n g u i s h e d a t 5:OO a . m . I n v e s t i g a t i o n showed t h a t t h e l o n g i t u d i n a l seam of the 8-inch p i p e bad s p l i t . The 8 l/Z-foot-long s p l i t was l o c a t e d on t h e s i d e o f t h e p i p e at the 9-o'clock p o s i t i o n . The p i p e w a s manufactured by the Jones and L a u g h l i n S t e e l Corporation i n 1960 and had the f o l l o w i n g s p e c i f i c a t i o n s : 8 5/8-inch o u t s i d e diameter API 5LX-52 electric r e s i s t a n c e weld (ERW) .219-inch w a l l t h i c k n e s s 2,650-psig i n t e r n a l p r e s s u r e minimum y i e l d s t r e n g t h 3,350-psig u l t i m a t e b u r s t i n g at ( S M Y S ) s t r e n g t h s p e c i f i e d When t h e p i p e f a i l e d , the pump s t a t i o n was o p e r a t i n g at 1 , 5 7 0 p s i g (about 59 p e r c e n t of S M Y S ) -- w e l l below t h e 72 p e r c e n t of SMYS s p e c i f i e d by F e d e r a l r e g u l a t i o n s . When t h e l i n e was c o n s t r u c t e d , t h i s s e c t i o n had been t e s t e d h y d r o s t a t i c a l l y t o 1 , 6 6 0 p s i g f o r 8 h o u r s . The MAPCO LPG system h a s s u s t a i n e d a series of l o n g i t u d i n a l p i p e seam f a i l u r e s . From January 1968 t o t h e d a t e of t h e W h i t h a r r a l a c c i d e n t , 1 4 l o n g i - t u d i n a l p i p e seam f a i l u r e s o c c u r r e d which r e s u l t e d i n 6 f a t a l i t i e s and the l o s s of over 60,000 b a r r e l s (2,520,000 g a l l o n s ) of LPG. Of these 1 4 seam f a i l u r e s , 10 o c c u r r e d i n 8-inch p i p e and a t p r e s s u r e s r a n g i n g from 1,265 p s i g t o 1,570 p s i g ; t h e a v e r a g e p r e s s u r e was 1,445 p s i g . 1825#

Page 2- 2 - As a result of an accident which occurred in Nebraaka on December 5, the Nebraska State Fire Marshal ordered MAPCO to reduce its operating pressure and to hydrostatically retest 52 miles of pipeline. During the tests, 19 longitudinal seams failed. The average pressure at which they failed was 2,235 psig. This pipe also was manufactured by the Jones and Laughlin S Corporation. Metallurgical analysis revealed that most of the accide caused when the electric resistance weld (ERW) in the longitudinal pi failed. Therefore, the National Transportation Safety Board re Mid-America Pipe Line System: Examine its leak records involving pipe seam failur to determine whether other sections of its system may be inadequate, and retest these areas hydrostatically. (P-76-22) (Class I, Urgent Followup) Retest hydrostatically all of the sections which contain ERW pipe manufactured by the Jones and Laughlin Steel Corporation and which are near schools, hospitals, and populated areas. (P-76-23) (Class I, Urgent Followup) Use internal pipeline inspection equipment in the sections which are not retested hydrostatically to detect any longitudinal pipe seam defects. (P-76-24) (Class 11, Priority Followup) Reduce the pressure in those sections where seams failed until they can be retested or inspected internally. The pressure should not exceed 1,155 psig. (P-76-25) (Class I, Urgent Followup) TODD, Chairman, McADAMS, HOGUE in the above recommendalions. THIS DOCUMENT WILL BE RELEASED TO THE PUBLIC ON THE DATE SHO PUBLIC DISSEMINATION OF THIS DOCUMENT SHOULD BE MADE BEFORE#