NTSB Safety Recommendation Letter P-76-005

Page 1Official PDF, .., . P I ' . ' , . ,..., !' NATIONAL TRANSPORTATION SAFETY BOARD WASHINGTON, D.C. I S S U E D : February 29, 1976 Forwarded to: Honorable William T. Coleman, Jr. Secretary Washington, D. C. 20590 Department of Transportation \ SAFETY RECOMMENDAT I ON (SI i P-76-5 At 9:45 p.m. on May 21, 1974, a 6-inch gas-gathering pipeline, owned by the Texas Oil and Gas Corporation, ruptured at the edge of a rural road south of Meridian, Mississippi. Three vehicles entered the area which contained the escaping gas, and stalled near the rupture. The gas ignited at 10:05 p.m., and five persons died as a result. Three vehicles were destroyed and 40 acres of woodland were burned. Although less than 4 years old, the 6-inch pipe had corroded internally and had been embrittled by hydrogen. The pipeline operator had not detected the corrosion although some corrosion test coupons had been installed. The pipeline had not been scraped internally often enough; consequently, liquids accumulated in the bottom of the pipe. The pipe ruptured at 300 psig - - well below its specified minimum yield strength - - at a weak point thinned by internal corrosion and further weakened by hydrogen embrittlement. In addition to the accident near Meridian, two other recent accidents on unregulated rural gas-gathering lines claimed nine lives (Kilgore, Texas, on September 7, 1975, and Mooreland, Oklahoma, on January 7, 1976). The design, construction, testing, operation, and maintenance of pipelines which transport and distribute natural gas have been federally regulated for several years. However, until Jan. 1975, there was no clear-cut Federal authority to regulate gas-gathering pipelines in rural areas. 1738#

Page 2Therefore, t h e National Transportation Safety Board recommends t h a t the Department of Transportation: Promulgate resulations under t h e Hazardous Materials Act f o r n a t u r a l gas-gatherii regulations promulgated for l i n e s i n 49 CFR 192. (P-76. REED, Acting Chairman, McADAMS, THAYER, BURGESS, and Mmmhars. ronrurred i n t h e above recommendation. ., NAIIONAL IRANSPORIAIlON SAFEIY B O A m WASHINC~ON. D C 30594 OFFICIAL UUSlNESS PENALTY FOR PBIVAIE USE 8300#