NTSB Safety Recommendation Letter P-78-001 through P-78-008

Page 1Official PDFYL&. P-91 NATIONAL TRANSPORTATION SAFETY BOARD WASHINGTON, D.C. 1SSUED:February 8, 1978 _--_I--_________________________________- Forwarded to: M r . B. H. Cooksey, Jr. President Consolidated Gas Supply Corporation 445 W . Main S t r e e t Clarksburg, West Virginia 2 6 3 0 1 SAFETY RECOMMENDATION(S) P-78-1 through P-78-8 A t 4 : 3 0 a.m., e . d . t . , on J u l y 20, 1977, a 12-inch propane pipeline, owned by t h e Consolidated Gas Supply Corporation, ruptured near t h e town of Ruff Creek, Pennsylvania. The l i q u i d , under 450-psig pressure, escaped from t h e p i p e l i n e , vaporized, and propane vapors s e t t l e d l i k e a fog over t h e bottom of a v a l l e y . About 6 a.m., two men i n a pickup truck entered t h e propane cloud; the truck s t a l l e d and t h e propane gas ignited when an attempt was made t o r e s t a r t the truck. A f l a s h f i r e , approximately 100 yards wide, followed a streambed located along t h e bottom of t h e v a l l e y and burned everything i n i t s path f o r a distance of l m i l e . The flames were over 100 f e e t high a t t h e p o i n t of t h e rupture and burned f o r 1 4 hours u n t i l the remaining propane l i q u i d i n the p i p e l i n e could be i s o l a t e d i n the p i p e l i n e by the use of valves and stopples. A s a r e s u l t of t h i s accident, t h e 2 persons i n t h e truck were k i l l e d , t h e truck w a s destroyed, 57 head of c a t t l e were k i l l e d , overhead power and telephone lines were destroyed, a hay storage shed containing 450 b a l e s of hay was burned, 1,800 b a r r e l s of propane burned, and a meadow and wooded area 1 m i l e long by 100 yards wide was burned. - 1/ For more d e t a i l e d i n f ormation about this accident, read “Pipeline Accident Report -- Consolidated Gas Supply Corporation, Propane Pipeline Rupture and F i r e , Ruff Creek, Pennsylvania, J u l y 20, 1977” (NTSB-PAR-78-1) . 2 2 6 0#

Page 2The Safety Board is concerned t stress-corrosion cracks (SCC) i n t h i sagbend t h a t i s adjacent t o t h e f i e 1 accident. Gas pipelines a r e o f t e n t particle-inspection method of nondestructive t e s t i n g t h a t contains SCC is exposed f o r m a i Stress-corrosion cracking has o of gas compressor s t a t i o n s with most the s t a t i o n . Since t h i s propane l i n e was formerly a gas p i p e l i n e and t h e rupture occurred within 6 1/2 miles of a s t a t i o n , t h i s area within 10 m i l e s of t h e former compress suspect. There i s evidence t h a t t h e s t r e s s e s necessary t came from e a r t h subsidence due t o t h which has taken place between I n t e r s t a t e Highways 70 There were no w r i t t e n procedures f o r t h e normal o r operations of t h i s propane p i p e l i n e as required by 49 CFR 195. there had been, o r if there had been a control center where a1 p e r t i n e n t pipeline operations d suspected and f i e l d personnel d time of t h e leak and t h e i g n i t i o n The t r a i n i n g of the operating personnel a P l a n t was not s u f f i c i e n t f o r them t o determine of over 100 psig w a s due t o a pipe meter on t h e i n l e t of t h e p i p e l i n e , o r an e l e c t r o n i c would have a l e r t e d them t h a t a d d i t i o n a l liquidswere and t h a t t h e r e must have been a p i p e l i n e rupture. Therefore, the National Transportation S a f e t t h e Consolidated Gas Supply Corporation: Inspect t h e f i e l d sag adjacent t o t h e overb o t h e r known l o c a t i o n s where t h e p i p e l i n e h undergone settlement of t h i s type w i t h t h e magnetic-particle-inspection o r other s u i t technique, f o r s i g n s of Replace t h e sagbend o r o is present. (Class 11,#

Page 3- 3 - T e s t pipe f o r stress-corrosion cracking using a nondestructive t e s t i n g method such as t h e magnetic- particle-inspection method or other s u i t a b l e technique every time t h e p i p e l i n e i s exposed f o r maintenance purposes. (Class 11, P r i o r i t y Action)(P-78-2) E s t a b l i s h w r i t t e n procedures t o insure the s a f e operation and maintenance of t h i s p i p e l i n e system under normal and emergency conditions a s required by Federal regulations. (Class 11, P r i o r i t y Action) (P-78-3) I n s t a l l a meter at t h e Hastings Extraction P l a n t on t h e i n l e t t o t h e propane p i p e l i n e t o determine how much l i q u i d is entering t h e pipeline. (Class 11, P r i o r i t y Action) (P-78-4) I n v e s t i g a t e the f e a s i b i l i t y of detecting p i p e l i n e l e a k s by t h e use of e l e c t r o n i c In/Out flow monitors or other l e a k detection devices, and i n s t a l l one capable of detecting both small and large leaks. (Class 111, Longer Term Action)(P-78-5) E s t a b l i s h a control center f o r the l i q u i d propane p i p e l i n e and telemeter a l l pressure, flow, and other p e r t i n e n t data necessary f o r t h e s a f e operation of t h i s p i p e l i n e t o t h i s c e n t r a l location. (Class 111, Longer T e r m Action) (P-78-6) Inspect on a random sample b a s i s the segment of p i p e l i n e 10 m i l e s downstream of the former Preston Compressor Station, including t h e area between I n t e r s t a t e Highways 70 and 79 where coal mines are prevalent, f o r other evidence of stress-corrosion cracking or increased-depth, general corrosion p i t t i n g . Increase cathodic p r o t e c t i o n or consider l i n e replacement i n areas where severe corrosion or stress-corrosion cracking i s found. (Class 11, P r i o r i t y Action) (2-78-7) Train pump s t a t i o n personnel on pump maintenance procedures and how t o t e l l the difference between l i n e pressure l o s s e s caused by leaks and by pumps being vapor locked. (Class 11, P r i o r i t y Action)(P-78-8) McADAMS, HOGUE and K I N G , Members, concurred i n t h e above recommendations. BAILEY, Acting Chairman, d i d not p a r t i c i p a t e . Acting Chairman 2260#