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Safety Recommendation Details

Safety Recommendation R-95-012
Details
Synopsis: ON 6/6/94, A CONDUCTOR FOR THE NORFOLK SOUTHERN RAILWAY COMPANY DETECTED PRODUCT LEAKING FROM THE BOTTOM OF TANK CAR UTLX 79211 IN THE NORFOLK SOUTHERN HARRY DEBUTTS YARD IN CHATTANOOGA, TENNESSEE. THE TANK CAR CONTAINED 12,184 GALLONS OF A 75-PERCENT CONCENTRATION OF ARSENIC ACID, WHICH IS CLASSIFIED AS A POISONOUS MATERIAL & ALSO DESIGNATED AS A MARINE POLLUTANT UNDER THE DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS.
Recommendation: THE NTSB RECOMMENDS THAT THE UNION TANK CAR COMPANY: INSPECT A REPRESENTATIVE SAMPLE OF UNION-BUILT TANK CARS EQUIPPED WITH THE SAME CONFIGURATION OF HOUSING FOR THE EDUCTION PIPE & BOWL-SHAPED SUMP AS UTLX 79211, & BASED ON THE RESULTS OF THE INSPECTIONS, MODIFY ALL APPROPRIATE TANK CARS TO ENSURE THAT THE EDUCTION PIPE CANNOT CONTACT THE SUMP.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Railroad
Location: Chattanooga, TN, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA94SZ011
Accident Reports: ​Tank Car Failure and Release of Arsenic Acid
Report #: HZM-95-01
Accident Date: 6/6/1994
Issue Date: 3/2/1995
Date Closed: 1/5/2001
Addressee(s) and Addressee Status: Union Tank Car Company (Closed - Acceptable Action)
Keyword(s): Hazmat

Safety Recommendation History
From: NTSB
To: Union Tank Car Company
Date: 1/5/2001
Response: The Union Tank Car Company replies that it has inspected tank cars and has found no signs of contact between the eduction pipe and the sump. The company also has inspected all newly built tank cars from its East Chicago manufacturing facility and has found no problem. The Union Tank Car Company believes that Federal regulations prescribe adequate qualification requirements for existing tank cars. As part of those qualifications, interior inspections are required to detect any corrosion that may exist in tank car interiors, including the tank bottom. This inspection includes the sump area and interior coating conditions. The absence of coating damage is taken as confirmation that no contact between the eduction pipe and the sump has occurred. Based on this information, Safety Recommendation R-95-12 is classified “Closed—Acceptable Action.”

From: Union Tank Car Company
To: NTSB
Date: 10/2/2000
Response: Letter Mail Controlled 10/05/2000 3:35:20 PM MC# 2001491 We did initiate an inspection program; the cars we inspected showed no signs of contact between the eduction pipe and the sump. In addition, we conducted an inspection of newly built cars from our East Chicago manufacturing facility to determine whether new cars met the requirements of non-contact. Again, none were found to have contacting siphon pipes. Today, 49 CFR, Part 180, prescribes the qualification requirements for existing tank cars. As a part of the qualification process, interior inspections are carried out to detect any corrosion that may exist on the tank interiors, including the tank bottom. This inspection includes the sump area as a matter of course, as well as inspection of the interior coating condition in that area. The absence of coating damage is taken as confirmation that no contact between the eduction pipe and sump has occurred. Also, whenever eduction pipes are inserted into a tank, the normal practice is to specifically check for specified clearances. We believe these checks cover both the past and future performance of our tank cars. To date, no cars have been reported to have a condition similar to the condition alleged to have existed in UTLX 7921 1. Nonetheless, specific inspection instructions have been expanded to cover all cars equipped with pipe cap sumps. With regard to the findings of the NTSB investigation itself, we wish to affirm that our analysis of the facts support the conclusion that the eduction pipe did not contact the edge of the sump, and did not initiate the breach in the coating, which lead to subsequent corrosion and release of commodity into the environment. We base this conclusion on our assessment of certain measurements cited in the Metallurgists Factual Report (the "MFR") and other observations and tests. We are continuing to inspect our entire fleet, both as part of 49 CFR 180 inspections and as standard operating procedures when cars go on and off lease, or when other circumstances indicate the need for an interior inspection.

From: NTSB
To: Union Tank Car Company
Date: 7/25/2000
Response: ON 8/29/96, BASED ON INFORMATION FROM UNION TANK CAR'S LETTER OF 6/21/95, R-95-12 WAS CLASSIFIED "OPEN--UNACCEPTABLE RESPONSE," BECAUSE THE UNION TANK CAR COMPANY DID NOT AGREE TO INSPECT A REPRESENTATIVE SAMPLE OF THE TANK CARS BUILT UNDER DIFFERENT CERTIFICATES OF CONSTRUCTION. THE SAFETY BOARD ENCOURAGED THE UNION TANK CAR COMPANY TO AGAIN CONSIDER INSPECTION OF OTHER TANK CARS UNDER DIFFERENT CERTIFICATES OF CONSTRUCTION THAT HAVE THE CONFIGURATION OF SUMP AND EDUCTION PIPE SYSTEM AS THE TANK CAR INVOLVED IN THE ACCIDENT. WE RECEIVED NO FURTHER RESPONSE FROM YOUR COMPANY ON THIS MATTER. THE SAFETY BOARD WOULD APPRECIATE LEARNING OF ANY FURTHER ACTIONS UNION TANK CAR COMPANY HAS TAKEN SINCE OUR LAST CORRESPONDENCE OR INTENDS TO TAKE TO MEET THE INTENT OF R-95-12.

From: NTSB
To: Union Tank Car Company
Date: 8/29/1995
Response: THE BOARD AGAIN NOTES UNION'S DISAGREEMENT WITH OUR CONCLUSIONS REGRDING THE MISALIGNMENTOF THE EDUCTION PIPE SYSTEM IN TANK CAR UTLX 79211. WE ALSO NOTE THAT WHILE UNION HAS COMMITTED TO INSPECT THOSE TANK CARS BUILT UNDER THE SAME CERTIFICATE OF CONSTRUCTION AS UTLX 79211, UNION DOES NOT BELIEVE THAT INSPECTIONOF TANK CARS BUILT UNDER DIFFERENT CERTIFICATES OF CONSTRUCTION IS WARRANTED. NONETHELESS, THE BOARD BELIEVES THE PHYSICAL EVIDENCE FROM UTLX 79211 STRONGLY INDICATES THAT BECAUSE OF THE MISALIGNMENT OF THE EDUCTION PIPE SYSTEM, THE PIPE COULD HAVE & DID STRIKE THE EDGE OF THE SUMP, THEREBY DAMAGING THE COATING & RESULTING IN THE CORROSION OF THE TANK. BECAUSE A SIGNIFICANT NUMBER OF UNION-BUILT TANK CARS HVE THE SAME CONFIGURATION OF SUMP, HOUSING, & EDUCTION PIPE AS UTLX 79211, & BECAUSE THIS CONFIGURATION IS STILL AN OPTION FOR NEWLY CONSTRUCTED TANKCARS, THE BOARD REMAINS CONCERNED THAT OTHER UNION-BUILT TANK CARS WITH THE SAME STYLES OF SUMP & EDUCTION PIPE MAY HAVE SIMILAR ALIGNMEN PROBLEMS & MAY FAIL IN A SIMILAR MANNER. THEREFORE, THE BOARD AGAIN ENCOURAGE UNION TO INSPECT A REPRESENTATIVE POPULATION OF ITS TANK CARS THAT HVE THIS CONFIGURATION OS SUMP & EDUCTION PIPE SYSEM BUT WERE NOT BUILT UNDER THE SAME CERTIFICATE OF CONSTRUCTION AS UTLX 79211. BECAUSE UNION HAS NOT AGREED TO INSPECT REPRESENTATIVE SAMPLE OF ITS TANK CARS, R-95-12 HAS BEEN CLASSIFIED "OPEN--UNACCEPTABLE RESPONSE."

From: Union Tank Car Company
To: NTSB
Date: 6/21/1995
Response: I HAVE RECEIVED & REVIEWED YOUR 5/8/95, CORRESPONDENCE REGARDING RECOMMENDATIONS R-95-12 & R-95-13. ON BEHALF OF UNION TANK CAR COMPANY, I APRECIATE THE NTSB NOTING UNION TANK CAR'S DISAGREEMENT WITH THE NTSB'S CONCLUSIONS REGARDING THE MISALIGNMENT OF THE EDUCTION PIPE SYSTEM IN UTLX N9211. UNION TANK CAR DOES NOT AGREE THAT THE RELEASE OF ARSENIC ACID FROM UTLX 79211 WAS "CAUSED BY MISALIGNMENT OF THE SUMP & HOUSING GUIDE FOR THE EDUCTION PIPE, WHICH RESULTED IN MECHANICAL DAMAGE TO THE COATING OF THE TANK CAR AT THE SUMP & SUBSEQUENT CORROSION & FAILURE OF THE TANK SHELL." UNION TANK CAR DOES NOT AGREE THAT THE FINDINGS SUPPORT A CONCLUSION THAT THE EDUCTION PIPE CONTACTED THE SUMP IN UTLX 79211. NONETHELESS, UNION TANK CAR, IN RESPONSE TO YOUR 3/2/95, CORRESPONDENCE PROPOSED TO INSPECT ALL OTHER CARS BUILT ON THE SAME CERTIFICATE OF CONSTRUCTION AS UTLX 79211 & DEPENDING ON THE RESULTS OF THE INSPECTION, CONDUCT FURTHER INSPECTIONS & RESPOND AS WARRANTED. AT THIS TIME, UNION TANK CAR IS CURRENTLY IN THE PROCESS OF INSPECTING THOSE CARS BUILT UNDER THE SAME CERTIFICATE OF CONSTRUCTION AS UTLX 79211. SUCH CARS WOULD INCLUDED UTLX 79204, UTLX 79209 (LEASED BY HICKSON CORPORATION) & WHICH HAVE ALREADY BEEN INSPECTED BY UNION TANK & THE NTSB. UNION TANK WILL CONTINUE TO INSPECT ADDITIONAL TANK CARS BUILT UNDER THE SAME CERTIFICATE OF CONSTRUCTION AS UTLX 79211. IN REVIEWING YOUR 5/8/95, CORRESPONDENCE, IT APPREARS THAT YOUR ARE REQUESTING UION TANK CAR COMPANY TO EXPAND INSPECTION BEYOND THOSE TANK CARS BUILT UNDER THE SAME CERTIFICATE OF CONSTRUCTION AS UTLX 79211. THE NTSB'S REQUEST APPEARS TO BE BASED ON SOME FINDINGS WITH RESPECT TO UTLX 75951, WHICH WAS BUILT UNDER A DIFFERENT CERTIFICATE OF CONSTRUCTION THAN UTLX 79211. UNION TANK COMPANY RESPECTFULLY DISAGREES THAT UTLX 75951 WARRANTS AN EXPANSION OF THE INSPECTION BEYOND THOSE CARS BUILT UNDER UTLX 79211. IN YOUR 5/8/95, CORRESPONDENCE, YOU INDICATE THAT "THE EDGE OF THE SUMP IN UTLX 75951 WAS ALSO CHIPPED & BEGINNING TO CORRODE IN A SIMILAR MANNER AS UTLX 79211." AGAIN, UNION TANK CAR COMPANY DOES NOT BELIEVE THIS FINDING SUPPORTS AN EXPANDED INSPECTION TO INCLUDE A REPRESENTATIVE SAMPLE OF UNION TANK CAR'S TANK POPULATION. UION TANK CAR COMPANY BELIEVES THAT IT IS IMPORTANT TO NOTE THAT DESPITE YOUR FINDING THAT UTLX 75951 WAS CHIPPED & BEGINNING TO CORRODE IN A SIMILAR MANNER AS UTLX 70211, THE NTSB FOUND AT PAGE 35 "THE SADDLE-SHAPE PIPE GUIDE WAS INTACT & PREVENTED THE EDUCTION PIPE FROM STRIKING THE EDGE OF THE SUMP." MOREEVER, AT PAGE 34-35, THE NTSB CONCLUDED THAT THE ALIGNMENT OF THE EDUCTION PIPE WAS NOT CONCENTRIC TO THE BOWL-TYPE SUMP IN UTLX 79204, UTLX 79206 & 7909. DESPITE THE NTSB'S CONCLUSION THAT THE ALIGNMENT OF THE EDUCTION PIPE IN UTLX 79204, 79206, & 79209 WERE NOT CONCENTRIC TO THE BOWL-TYPE SUMP, THERE WAS NO FINDING THAT THE EDUCTION PIPE COULD CONTACT THE SUMP IN ANY OF THESE CARS. ADDITIONALLY, THE NTSB DID NOT FIND ANY CORROSION AT THE SUMP AREA IN UTLX 79204, 79209. BASED ON THE ABOVE, UNION TANK CAR WOULD LIKE TO CONTINUE WITH ITS INSPECTION OF TANK CARS UDNER THE SAME CERTIFICATE OF CONSTRUCTION AS UTLX 79211. UNION TANK CAR RESPECTFULLY SUGGESTS THAT THE FINDINGS IN UTLX 75951 & 79204, 79206 & 79209 DO NOT WARRANT EXPANSION OF THE INSPECTION PROCESS BEYOND THOSE CARS BUILT UNDER UTLX 70211. IN FACT, UNION TANK CAR RESPECTFULLY SUGGESTS THAT THE FINDINGS IN THE ABOVE-REFERENCED CARS INDICATE THAT THE ALLEGED MISALIGNMENT OF THE EDUCTION PIPE IS NOT INVOLVED IN ANY CORROSION AT SUMP AREA.

From: NTSB
To: Union Tank Car Company
Date: 5/8/1995
Response: THE BOARD NOTES THAT UNION WILL INSPECT ALL OTHER TANK CARS BUILT ON THE SAME ORDER AS UTLX 79211, & DEPENDING ON THE RESULTS OF THE INSPECTIONS, DETERMINE WHETHER FURTHER INVESTIGATION & RESPONSE ARE NECESSRY. WE APPRECIATED UNION'S COMMITMENT TO INSPECT THESE TANK CARS. HOWEVER, AS NOTED IN THE ACCIDENT REPORT, THERE WAS ALSO MISALIGNMENT OF THE EDUCTION PIPE, SUMP, & PIPE GUIDE IN TANK CAR UTLX 75951, WHICH WAS BUILT UNDER A DIFFERENT ORDER THAN UTLX 79211. THE EDGE OF THE SUMP IN UTLX 75951 WAS ALSO CHIPPED & BEGINNING TO CORRODE IN A SIMILAR MANNER AS UTLX 79211. CONSEQUENTLY, THE BOARD BELIEVES THAT A REPRESENTATIVE SAMPLE OF UNION'S TANK CAR POPULATION WITH THIS TYPE OF EDUCATION PIPE SYSTEM NEEDS TO BE INSPECTED BEFORE UNION CAN DETERMINE THE EXTENT TO WHICH OTHER TANK CARS MAY HAVE SIMILAR ALIGNMENT PROBLEMS. PENDING YOUR RESPONSE, R-95-12 IS CLASSIFIED "OPEN--ACCEPTABLE RESPOSNE."

From: Union Tank Car Company
To: NTSB
Date: 4/4/1995
Response: UNION TANK CAR COMPANY DOES NOT AGREE THAT THE RELEASE OF THE ARSENIC ACID FROM UTLX 79211 WAS "CAUSED BY MISALIGNMENT OF THE SUMP & THE HOUSING GUIDE FOR THE EDUCTION PIPE, WHICH RESULTED IN MECHANICAL DAMAGE TO THE COATING OF THE TANK CAR AT THE SUMP & THE SUBSEQUENT CORROSION & FAILURE OF THE TANK SHELL." UNION TANK CAR IS OF THE POSITION THAT THE NTSB DID NOT FULLLY CONSIDER ALL OF THE EVIDENCE IN MAKING ITS FINDINGS. UNION TANK CAR WILL INSPECT ALL OTHER TANK CARS BUILT ON THE SAME ORDER AS UTLX 79211. DEPENDING ON THE RESULTS OF THE INSPECTIONS, UNION WILL DETERMINE WHETHER FURTHER INVESTIGATION & RESPONSE IS NECESSARY.