NTSB Safety Recommendation Letter P-74-028

Page 1Official PDFs WASHINGTON, D.C. ISSUED: September 2.2, 1974 Forwarded to: Honorable Claude S. Brinegar Secretary of Transportation - Washington, D. C. 20590 i SAFETY RECOMMENDAT I ON (S) . . P-74-28 Two recent anhydrous ammonia pipeline accidents have occurred on a n 8-inch pipeline owned and operated by Mid America Pipe Line Company (MAPCO). On December 6, 1973, a MAPCO pipeline failed n e a r Conway, Kansas, in a section of pipeline which had been damaged previously. On August 13, 1974, the same MAPCO pipeline failed n e a r Hutchinson, Kansas. This failure was a l m o s t identical to the f i r s t and was only 23 miles away. In the December 6 accident, a pump station was started against a closed valve, and the p r e s s u r e became so great that the pipeline failed i n a previously damaged section. A s a result of the accident, two persons who drove through the ammonia vapors were hospitalized; s e v e r a l r u r a l residents were evacuated f r o m the area; and 89, 796 gallons of anhydrous ammonia were lost. In the August 13 accident, MAPCO personnel started up the pump station against a closed valve, and again, the pressure became s o g r e a t that the pipeline ruptured. A s a result of the accident, 3 police officers were treated f o r ammonia inhalation; approximately Z O O persons were evacuated f r o m the area of the vapors; t r e e s , lawns, shrubbery, and c r o p s were burned;and a n estimated 11, 000 fish were killed. The maximum operating p r e s s u r e on the pipeline system established by MAPCO is 1, Z O O psig. Before the pipeliiie w a s placed in service in 1968, i t was tested to a p r e s s u r e of 1, 540 psig. On August 1 3 , 1974, the pressure a t the point of failure was estimated to be 1, 5 2 0 psig. 1358#

Page 2Honorable Claude S. Brinegar - 2 - 49 CFR 195, Transportation of Liquids by Pipeline, r e q u i r e s that . . . "No c a r r i e r m a y permit the p r e s s u r e i n a pipeline during s u r g e s o r other variations f r o m n o r m a l operations to exceed 110 percent of th operating p r e s s u r e limit established . I . by the internal design p r e s s u r e of the pipe o r other pipeline components o r 80 percent of t e s t p r e s s u r e . It further require equipment be provided to control estimated 1, 520 psig greatly e x c o r surge p r e s s u r e of 1, 320 psig, regulations. The National Transportatio Office of Pipeline Safety of the Department of Transportation: Require the Mid America Pipeline Company to implement immediately corrective m e a s u r e s i n pipeline controls, protective equipment, and methods of operations, to a s s u r e that the maxi- m u m operating p r e s s u r e established for this pipeline is not exceeded. The Safety Board's repo the near future, will include a c factors which a r e common to both of these accidents on the MAPC pipeline" REED, Chairman, McADAMS, THAYER, BURGESS and HALEY M e m b e r s , concurred in the above recommendation. c c : Mid America Pipeline Company#