NTSB Safety Recommendation Letter P-90-003 through P-90-005

Page 1Official PDFNational Transportation Safety Board Washington, D.C. 20594 Safety Recommendation Honorable Samuel TI Skinner Secretary U.S. Department o f Transportation 400 Seventh S t . S.W Washington, D.C. 20590 About 5:50 p.m. c e n t r a l d a y l i g h t t i m e on October 3, 1989, t h e United States menhaden' f i s h i n g vessel NORTHUMBERLAND, owned and operated by the Zapata Haynie Corporation (vessel owner), w a s backing and maneuvering i n 9 t o 11 f e e t o f w a t e r when the s t e r n o f the vessel s t r u c k and ruptured an offshore 16-inch n a t u r a l gas transmission p i p e l i n e owned by Natural Gas P i p e l i n e Company o f America ( p i p e l i n e company). Natural gas under 835 pounds per square i n c h pressure was released. An undetermined source on board the vessel i g n i t e d the gas, and w i t h i n seconds, the e n t i r e vessel was engulfed i n flames. The f i r e on the vessel burned u n t i l 4:30 a.m on October 4 , when it burned i t s e l f o u t . Leaking gas from the p i p e l i n e also continued t o burn u n t i l t h e f l o w o f gas subsided and the f i r e s e l f - e x t i n g u i s h e d about 6 a.m. on October 4 . Eleven o f fourteen crew members d i e d as a r e s u l t o f the accident. The vessel was located about 1/2 m i l e o f f s h o r e i n the G u l f o f Mexico (Gulf) and about 5 1/3 n a u t i c a l m i l e s west o f the j e t t i e s a t t h e entrance t o Sabine Pass, Texas. W i t h i n a few days f o l l o w i n g the accident, both the vessel owner and the p i p e l i n e company had d i v e r s survey the p i p e l i n e on e i t h e r side o f the accident l o c a t i o n . Both d i v i n g r e p o r t s i n d i c a t e t h a t t h e p i p e l i n e was exposed above the n a t u r a l bottom and had var.ying amounts o f marine growth on the remaining p o r t i o n s o f exposed pipe. A marine b i o l o g i s t contracted by t h e Safety Board a l s o examined t h e marine growth on t h e p i p e l i n e sections l a t e r recovered. The marine b i o l o g i s t estimated, on t h e basis o f the type and e x t e n t o f marine growth found, t h a t some sections o f t h e p i p e l i n e had been exposed above the n a t u r a l bottom o f the G u l f from 1 t o 10 years. i n s h a l i o u r e v e n u e s ' M e n h a d e n i s a h e r r i n g . L i k e f i s h a b o u t 8 i n c h e s i n L e n g t h a n d i s f o u n d s t a t e r s f r o m m e n h a d e n a l o n g t h e f i s h i n g G u t f o f M e x i c o a n d a r e e s t i m a t e d a t t h e A t l a n t i c O c e a n . I200 m i l l i o n p e r y e a r . G r o s s 52ClBA#

Page 22 The accident pipeline is an interstate transmission pipeline subject to the Department of Transportation's (DOT) natural gas pipel ine safety standards in Part 192 of Title 49 of the Code of Federal Regulations (CFR). The pipeline was built in 1973 and as-built construction plans show that it was buried 8 1/2 to 10 feet below the natural bottom of the Gulf at the accident site. Current DOT pipeline safety regulations (49 CFR Parts 192 and 195) require, at the time of a pipeline's construction, a minimum burial depth of 3 feet when the water depth is 12 feet or less. Right-of-way permits for the pipeline's construction were required from both the Minerals Management Service (MMS) of the Department of the Interior (DOI) and the General land Office of Texas because the pipeline crosses the Outer Continental Shelf (OLS) and Texas State waters. The Safety Board conducted a public hearing concerning this accident on December 11 and 12, 1989, in Houston, Texas. Testimony on menhaden fishing vessel operations in the Gulf were provided by a representative of the vessel owner, a representative of a second company operating a fleet of menhaden fishing vessels, and a representative of the Louisiana Shrimping Association. The vessel owner estimated that 73 menhaden fishing vessels operate in the Gulf. According t o the vessel owner, 80 to 90 percent of the menhaden are caught within 3 miles of shore, and 40 to 50 percent within 1 mile of shore. The second menhaden official reported similar percentages for his company. The shrimping association official estimated that the number of full- and part-time shrimping vessels operating in the Gulf is between 30,000 and 35,000. He also indicated that shrimp fishermen will trawl wherever shrimp can be found, including the near-shore areas. Although all three officials knew about and were generally aware of the presence of offshore pipelines in the Gulf of Mexico, they testified that it was their belief that all offshore pipelines in shallow waters are buried and do not pose a danger to marine vessels and their operations. According to an official of the U.S. Geological Survey, coastal erosion and subsidence can be quite severe along the Gulf coast. Winter storms, hurricanes, and the placement of man-made structures such as jetties can accelerate the erosion and subsidence rates and lead to the removal of sediment covering a pipeline. Testimony was also taken from representatives of the Office of Pipeline Safety (OPS) of the Research and Special Programs Administration, MMS, and the Pipeline Safety Group of the Railroad Commission of Texas. The OPS Southwest Region representative estimated there are about 130 offshore pipeline operators within the region. However, OPS does not maintain information on the number, type, and locations of offshore pipelines. MMS, which issues leasing permits and right-of-way permits on the OCS for offshore pipelines, estimated that there are nearly 18,000 miles of offshore oil and gas pipelines on the OCS of the Gulf. Of this total, 4,550 miles are regulated by MMS, and 13,300 miles are regulated by OPS. In addition to the pipelines regulated by OPS and MMS, there are an unknown number of offshore pipel ines not subject to Federal jurisdiction. For example, the Railroad Commission of Texas, which regulates a portion of offshore pipeline systems originating within State waters, estimates there are 70 pipeline systems with 600 miles of pipeline under its jurisdiction. The Commission representative#

Page 33 had no estimates of the number of pipeline systems or miles of pipelines that are in Texas waters hut not subject to the Commission's jurisdiction. Other Gulf coast states also have offshore pipeline systems located in state waters, and the extent of their jurisdiction was not discussed at the Safety Board's hearing. OPS, MMS and the Texas Railroad Commission have requirements to bury certain offshore pipelines at the time of construction, although pipelines constructed before Federal requirements were in effect were not required to be and may not have been buried. Other OPS regulations also require that offshore pipelines be protected from ship anchors and fishing operations. MMS regulations authorize the regional supervisor to require a burial depth to reduce the likelihood that the pipeline may constit.ute a hazard to trawling operations or other uses. Regarding surveillance and inspection of offshore pipelines, representatives of all three agencies indicated they accept aerial surveillance and do not require pipeline operators to monitor the pipelines and verify that the original depth of cover is maintained throughout the service life of the pipeline. OPS and MMS officials acknowledged, however, that an unburied pipeline in shallow waters constitutes a hazard, and should he reburied if the condition is known by the operat,or. However, none of the officials for pipeline company, OPS, MMS or the Texas Railroad Commission could recommend an effective method to verify the amount of cover over existing buried pipelines. Despite regulatory requirements to bury certain portions of offshore pipelines during their construction, the absence of regulations that require surveillance to verify that pipelines remain buried subjects the operators of marine vessels to potential danger, particularly in depths of water comparable to the draft of the vessel. According to the U.S. Geological Survey, erosion and subsidence are known to he severe along some areas of the Gulf coast; therefore, the chance that a buried pipeline will become exposed in the near-coastal areas is increased. The pipelines that were never required to be buried pose similar risks to marine vessel operations. In addition to this accident, a Zapata Haynie vessel struck a submerged natural gas pipeline in 1981. Although the pipeline was ruptured, the natural gas was not ignited, and no one was injured. In 1987, the menhaden fishing vessel SEA CHIEF also struck and ruptured an offshore natural gas/liquids pipeline in Louisiana waters, resulting in a fire and the deaths of two members of the crew. OPS has indicated that since 1985 there have been 21 reported incidents in which marine vessels have damaged offshore pipelines, including the SEA CHIEF and NORTHUMBERLAND accidents. Although the number of reported incidents involving offshore pipe1 ines and marine vessels remains small compared to the estimated numbers of pipelines and commercial fishing and shrimping vessels, the Safety Board is concerned this may be a growing problem. Although only two of the incidents noted have involved a loss of life, both occurred within the last three years. Consequent1 y, marine vessel operators cannot presume that offshore pipelines in water depths less than 12 feet are buried and their vessels, therefore, are protected.#

Page 44 The magnitude and urgency o f t h e problem a r e unknown because o f t h e l a c k of complete information about the number, type, and l o c a t i o n o f offshore p i p e l i n e s i n t h e G u l f o f Mexico, and the l a c k o f e f f e c t i v e s u r v e i l l a n c e procedures t o v e r i f y t h a t offshore p i p e l i n e s remain s a f e l y buried. The absence of r e g u l a t i o n s t o r e q u i r e t h a t b u r i a l depths be maintained f o r o f f s h o r e pipe1 ines increases t h e l i k e l i h o o d t h a t other b u r i e d offshore p i p e l i n e s may a l s o become exposed above t h e n a t u r a l bottom o f t h e Gulf. The j u r i s d i c t i o n a l complexities among t h e various Federal and s t a t e agencies, and t h e a p p l i c a b i l i t y o f e x i s t i n g regulations, create a d d i t i o n a l d i f f i c u l t i e s . Consequently, t h e p o t e n t i a l danger t o l i f e and p r o p e r t y from f u t u r e accidents i s impossible t o estimate. Although DOT does not have j u r i s d i c t i o n over many o f f s h o r e p i p e l i n e s i n t h e Gulf, t h e Safety Board believes t h a t the DOT, as t h e primary Federal agency responsible f o r p i p e l i n e safety, i s best able t o organize and coordinate an e f f o r t by Federal, state, and i n d u s t r y organizations t o determine t h e danger o f offshore p i p e l i n e s t o marine vessels, and t o propose e f f e c t i v e methods t o inspect, maintain, and p r o t e c t o f f s h o r e p i p e l i n e s . The Safety Board a l s o believes t h a t t h e D O I , as t h e primary agency f o r OCS development, should a s s i s t the DOT i n t h i s e f f o r t . Therefore, t h e National Transportation Safety Board recommends t h a t the Department o f Transportation: Issue an advisory n o t i c e or use other means t o caution commercial f i s h i n g , shrimping, and other marine vessel operators i n t h e G u l f o f Mexico t h a t submerged o f f s h o r e p i p e l i n e s may be unprotected on t h e ocean f l o o r and t h a t marine vessels can damage such p i p e l i n e s and endanger t h e i r crews when operating i n water depths comparable t o a vessel’s d r a f t o r when operating bottom dragging equipment. (Class I, Urgent Action) (P-90-3) I d e n t i f y , w i t h t h e assistance o f t h e Department o f t h e I n t e r i o r and other G u l f Coast States t h a t may have j u r i s d i c t i o n , t h e type, number, l o c a t i o n , and owner o f a l l offshore p i p e l i n e s i n t h e G u l f o f Mexico. (Class I, Urgent Action) (P-90-4) Determine, w i t h t h e assistance o f the Department o f t h e I n t e r i o r , e f f e c t i v e methods o f inspection, maintenance, and p r o t e c t i o n f o r o f f s h o r e p i p e l i n e s located i n t h e G u l f o f Mexico t o depths o f water comparable t o t h e maximum d r a f t s o f marine vessels t h a t may operate outside o f established sea lanes. (Class 11, P r i o r i t y Action) (P-90-5)#

Page 55 KOLSTAD, Chairman, COUGHLIN, Acting Vice Chairman, LAUBER, and BURNETT Members, concurred in these recommendations.#