September 12, 2002

 

 

 

Honorable Carol J. Carmody, Chairman

Board of Inquiry

National Transportation Safety Board

490 L’Enfant Plaza East, S.W.

Washington, DC 20594

 

Re:    Proposed Findings, Proposed Probable Cause, and Proposed

          Safety Recommendations in the matter of the Derailment of

          Canadian Pacific Railway, Freight Train 292-16, Near Minot,

          North Dakota, on January 18, 2002

 

Dear Madam Chairman:

 

The Brotherhood of Maintenance of Way Employes (BMWE) has been granted party status by the Board in the above investigation.  BMWE participated in the NTSB public hearing held July 15-16, 2002 in Washington, D.C., and hereby submits these Proposed Findings, Proposed Probable Cause, and Proposed Safety Recommendations to the Board for consideration.

 

Proposed Findings  

 

At approximately 1:19 a.m., CST, January 18, 2002, Canadian Pacific Railway (CPR)Freight Train 292-16 with two locomotives and 112 cars derailed 31 cars near Minot, North Dakota.  Seven tank cars carrying anhydrous ammonia were breached, and a vapor plume covered the derailment site and community.  More than 210,000 gallons of anhydrous ammonia was released, resulting in a fatal injury to one local resident and the rescue of approximately 60-65 residents from the neighborhood.   More that 300 people were injured and approximately 15,000 people were affected. 

 

The operating crew of Freight Train 292-16 reported that they felt a rough spot while traveling eastbound at approximately 40 MPH on single main track near milepost (MP) 471.65 on CPR’s Portal Subdivision of the St. Paul Service Area.  The point of derailment was west of the City of Minot, N.D., within the limits of Ward County near MP 471.65.

Honorable Carol J. Carmody - 2 - September 12, 2002

 

 

 

The main track is owned, inspected, maintained and operated by CPR.  There is a substantial question as to whether the number of maintenance forces assigned is sufficient for the territory.  Track foreman Schoenberg has just two workers on his section crew.  They must inspect and maintain a 150-mile territory and in addition, are not infrequently assigned to assist crews in adjacent districts (NTSB Transcript at pp. 58-62).  Track supervisor Kroll, with only 16 track maintenance workers is responsible for 287 miles of branch and main line track, including classification yards and a number of industry tracks (NTSB Transcript at p. 98).  There are some 170 turn-outs and other switches in the territory (NTSB Transcript at p. 99).   Post-accident actions validate the lack of adequate staffing.  Following this derailment, approximately 60 track workers were added for a period of 8 weeks in order to effectuate the large number of repair orders specially issued by FRA.  Most of these workers were of furlough at the time the derailment occurred (NTSB Transcript at pp. 101, 199, and 200.).

 

The Portal Subdivision main track has a maximum allowable operating speed of 49 MPH for freight trains, designating it as Federal Railroad Administration (FRA) Class 4 track.  In the area of the derailment, CPR designated the maximum allowable speed at 40 MPH.   There have been substantial increases in the tonnage hauled over this track, with predictable added stresses, but no increases in track maintenance forces (NTSB Transcript at p. 62 and 99). As a result of the derailment, approximately 475 linear feet on main track was destroyed.  Thirteen (13) track panels were installed to restore operations.

 

The post accident inspection disclosed that the point of derailment occurred on tangent track with 100 RE pound continuous welded rail (CWR).  The rail through the derailment area was restressed in 1998 with new anchors applied.   The track structure also consisted of wooden crossties (approximately 22 per 39' rail length) and  double shoulder tie plates with 2-3 cut spikes per plate.  The track segment was supported with trap rock ballast with an approximate depth of 6-8 inches under the crossties.  Shoulder ballast was determined to be approximately 12 inches, and the crosstie cribs were full of ballast.  The rail was box anchored at every other tie with Improved Fair anchors.  The Track Group investigation did not observe a continuous or fully boxed anchoring pattern (every crosstie box anchored) in the area of the derailment. 

 

Recovered from the derailment site was a piece of track component located between two derailed cars (lumber car CP 319013 and tank car NATX 35798).   The track component represented the west half of a rail joint in the north rail.   The partial rail joint consisted of two bolts through rail joint bars affixed to 100 RE pound rail.   The rail in the joint bars exhibited some rail breakage.  The second half (east half) of the same rail joint was located within the proximity of where the first half of the joint bars and rail pieces were located.   Both of the joint bars were broken at the center portion of each bar and both joint bars appeared to contain fatigue fractures. It was determined that this rail joint was the east end of a plug section of rail cut in on the north rail in May 2000.  Each of the rail ends that comprised the east joint of the plug section also exhibited measurable rail end batter.

Honorable Carol J. Carmody - 3 - September 12, 2002

 

 

 

With regard to the subsequent breach of seven tank cars carrying anhydrous ammonia, it appears that the magnitude of the release, approximately 210,000 gallons of anhydrous ammonia, may be in part attributable to the occurrence of “brittle fracture” defects within the derailed tank cars themselves.  This phenomenon apparently manifests in tank cars manufactured with coarse-grain carbon steel alloys.  These course-grain, non-normalized steel tank cars are susceptible to “brittle fracture” defects, i.e., cracks or fractures which develop over time in the tank car shell to which relatively little energy need be applied to the crack or fracture area to progress a failure and possible catastrophic loss of load.    Cold weather operations also appear to increase the likelihood of the occurrence of brittle fracture tank car defects.

 

 

Proposed Probable Cause

 

BMWE’s review of available evidence and testimony of the parties leads us to conclude that the probable cause of the CPR derailment on January 18, 2002 at Milepost 471.65, west of Minot, N.D. was joint bar failure at the east end of a rail plug on the north rail.    BMWE concludes that the joint bars likely developed internal fatigue fractures between the center bolt holes, and these fatigue fractures, not detectable with the naked eye, led to a complete failure of the joint bars thus allowing the rail ends to “pull apart,” causing a track defect which lead to the derailment.  We also conclude that the probable cause of the joint bar failure was ultimately an insufficient anchoring pattern which caused the joint bars, joint bolts, and rail ends to be subjected to extreme forces caused by insufficiently restrained contraction of the rail ends during cold weather months.   The investigation record reflects the ambient temperature at the time of the derailment was approximately -5 degrees Fahrenheit.  

 

It is not entirely clear to BMWE whether the rail end fractures which occurred within the joint resulted from the forces exerted on the bolt holes and rail ends due to the insufficiently restrained longitudinal expansion and contraction of the rail within the joint, or whether the rail end fractures occurred as a result of the forces exerted on the rail end joint by the derailment itself.   Regardless, the underlying proposed probable cause was the absence of “full-boxed”  rail anchors approximately 200' each side of the failed rail joint.   A “full box” anchoring pattern at rail joints and other locations susceptible to the longitudinal forces of CWR is a well established and  generally accepted engineering norm within the industry.  The failure of CPR to require a full-box anchoring pattern every tie 190-200' each side of the joint is the probable cause for the rail joint failure, pull-apart,  and subsequent derailment.

 

 

 

 

 

 

Honorable Carol J. Carmody - 4 - September 12, 2002

 

 

 

Proposed Safety Recommendations

 

Proposed Recommendations to Canadian Pacific Railway:

 

1. Follow CPR’s requirements for rail anchoring found in SPC 19, Rail Anchors, in its entirety.   Specifically, assure compliance with Section 2.0(f) of SPC 19 which states, “For those joints created in CWR through the process of cutting in rails, box anchor every tie for the first 195 feet on either end of the strings that butt up to the newly installed rail.”    

 

2. Submit all SPC’s relative to CWR installation, renewal, repair, and maintenance in filing CPR’s CWR Program with FRA.

 

3. Require full box anchoring pattern 195'-200' each side of every rail joint in CWR.

 

4.  Increase quantity and quality of training programs for Track Inspectors and other persons qualified under 49 CFR 213.7 relative to the installation, renewal,  repair, and maintenance of CWR.  

 

5.Develop a user-friendly “field manual” for CWR installation, renewal, repair and maintenance where all CWR related standards and instructions can be readily accessed in one publication by persons qualified under 49 CFR Part 213.7

 

6. Institute and maintain a joint bar inspection and maintenance program, including the use of new technologies to inspect joint bars for internal defects.

 

7.Accelerate replacement of 100 RE pound rail on mainline track to a heavier rail section  on the Portal Subdivision.

 

8.Increase and maintain the number of track maintenance forces sufficient to facilitate pro-active track inspection and maintenance protocols and procedures.

 

9.Adopt a more comprehensive welding and joint elimination program, and comply with CPR’s own SPC’s regarding welding of rail plug joints within specified parameters.

 

 

Honorable Carol J. Carmody - 5 - September 12, 2002

 

 

 

Proposed Recommendations to the Federal Railroad Administration

 

1.Require, by regulation,  mandatory full box anchoring pattern 200' each side of every rail joint in CWR.

 

2.Require all railroads to submit full and comprehensive plans for every aspect of CWR installation, maintenance, repair, and renewal as part of their filing of a CWR Program to FRA.

 

3.Establish a mandatory list of items and specifications which must be included in each railroads’ filing of a CWR Program.

 

4.Require each CWR Program to include provisions for joint bar maintenance and inspection.

 

5.Develop regulatory guidelines for rail wear.

 

6.