R97V0063 - Transportation Safety Board of Canada Interim Railway Safety Recommendations concerning the identification and detection of railway roadbed instability (R97-01)(R97-02)
TSB Full Text Report (R97V0063):
http://www.tsb.gc.ca/eng/rapports-reports/rail/1997/r97v0063/r97v0063.asp
TSB Recommendation R97-01
Roadbed Subgrade Instability - (Action Required, as presented in the TSB Report)
The Board recommends that:
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The Department of Transport, in collaboration with Canadian National, Canadian Pacific Limited, and the British Columbia highway authority:
- identify locations where railway or adjacent highway roadbeds were constructed of fill laid on silts or other similar soil material;
- for those locations identified as per above, assess the adequacy of existing drainage for the spring run-off and determine if the roadbed foundations are susceptible to water saturation; and
- where applicable, implement a monitoring program to detect roadbed subgrade instability as a result of water saturation. (R97-01)
Transport Canada's Response (R97-01)
(signed by Minister on July 16th, 1997)
On May 2, 1997, Transport Canada's Pacific Region office convened a meeting with all stakeholders. The circumstances of this accident were reviewed in detail by Transport Canada's Railway Safety Officers and discussed with senior officers of the Canadian National Railway Company (CN), Canadian Pacific Limited (CP) and the British Columbia Ministry of Transportation and Highways (MoTH) to alert them to the potential hazard posed by severe water saturation in British Columbia.
Recommendation a)
CN, CP and MoTH have all performed extensive aerial and ground surveys throughout the Fraser and Thompson Canyons. Additionally, river inspections have also been performed with jet boats. CP did not identify any specific sites with conditions similar to Conrad. CN's consultant has identified approximately five sites with soil/topography/ possible water conditions similar to the Conrad site. They are drilling at two sites that are very close to Conrad as well as a number of holes at the Conrad site to determine as much as they can about conditions there. They have not yet received their consultant's recommendations regarding all five sites identified.
Recommendation b)
Culverts have been inspected and increased patrols have been instituted. The Department has also requested that the other parties conduct a joint geotechnical analysis to identify any other locations in British Columbia which are susceptible to collapse under similar conditions to that which occurred at Conrad. Dr. John Clague of Geological Surveys Canada has offered his services in this regard, once the TSB has completed its investigation.
Recommendation c)
A slump/washout detector has now been installed at Conrad. Contact lists and procedures are being developed between CN, CP, MoTH and the Department for use in the future during spring runoff.
Data from the event recorder of the train on the adjacent siding (from which the three loaded sulphur cars had fallen into the depression) suggest that the failure occurred long before the arrival of train Q-102. Yet, systems designed to provide warnings of track occupancy and track conditions did not provide such a warning. The Board is aware of several other occurrences where circuit integrity was sustained notwithstanding a complete roadbed failure; in other words the track was left suspended unsupported over an abyss, into which the oncoming trains plunged.
In July 1992, a CN freight train encountered a collapsed roadbed foundation near Nakina, Ontario. The train traveled onto the suspended portion of track and derailed into a beaver pond. Two crew members were killed and a third sustained serious injuries. The roadbed failure was caused by a sudden draw down of the water in a pond from a breached beaver dam. Apparently, no warning of the roadbed failure was available to this crew. (TSB Occurrence No. R92T0183.)
The TSB is currently examining the circumstances surrounding another recent roadbed failure which resulted in the derailment of CP freight train on the Parry Sound Subdivision near Pointe au Baril, Ontario on 7 April 1997. Although the locomotives and fourteen cars plunged into the depression, the crew members escaped without serious injury. Once again, following a roadbed failure involving the saturated soils associated with the spring run-off, there was no warning to the crew that the track was no longer supported by the roadbed. (TSB occurrence No. R97T0097.)
TSB Recommendation R97-02
Integrity of the Roabed - (Action Required, as presented in the TSB Report)
The Board recommends that:
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The Department of Transport, in collaboration with the Railway Association of Canada:
- evaluate the effectiveness of current track continuity warning systems vis-à-vis roadbed failures;
- evaluate alternative methods for confirming the integrity of the roadbed during high risk periods;
- sponsor research to develop more reliable technologies for monitoring the integrity of both the track and the roadbed. (R97-02)
Transport Canada's Response (R97-02)
(signed by Minister July 16th, 1997)
On May 8, 1997, Transport Canada Headquarters officials met with representatives of the Railway Association of Canada (RAC), CN Rail and CP Rail in order to develop an action plan on these recommendations. The purpose was to assess possible improvements to track continuity warning systems in terms of roadbed failures; and to evaluate alternative methods for confirming the integrity of the roadbed during high risk periods (one of which could be continued regular inspections combined with an appropriate water management system).
Current signal systems in place are highly effective in detecting the vast majority of rail breaks and preventing derailments. In addition, slide fences and avalanche detectors on posts are effective in detecting slides from above. However, these systems are not effective when it comes to confirming the integrity of the roadbed during high risk periods.
Representatives from Transport Canada, the Railway Association of Canada, the Railways, the Transportation Safety Board of Canada, the Transportation Development Centre and the National Research Council met with the Railway Research and Advisory Board on June 11, 1997, to discuss the issue of research on track and roadbed monitoring technology.
Existing technologies discussed include:
1. Level Beam Detector
Electro level (EL) Beam Sensors are designed to monitor differential movement and rotation in structures. Horizontal beam sensors monitor settlement and heave, and vertical beam sensors monitor lateral displacement and convergence.
This technology has been used in many track/tunnel construction projects in Europe and North America, and found to be an effective means of identifying deformations requiring remediation.
The ability to detect slide and washout conditions would be effective. The cost of implementing this technology would be low to moderate. The technology and its installation is considered feasible by railway officials.
2. Time Domain Reflectometry
Time Domain Reflectometry technology has been on the market for about a decade. Its application in determining cable or wire integrity over long distances has further developed into the Phase Tracking (PT) technique of continuous level control utilized to measure solid and liquid products in silos, tanks, and other enclosed vessels.
A conceptual analysis will be undertaken to determine if phase tracking can be utilized to obtain a sub-roadbed signature using the existing buried fibre optic cable with ground sheath as the "sensor". The intent would be to generate an alarm when signature variances occur due to washout or ground slip conditions.
The ability to detect slide and washout conditions would be effective. The cost of implementing this technology would be low to moderate. There is a technological risk involved in developing and implementing the technology, however, it is considered to be feasible.
3. Guided Radar System
Guided Radar technology has been used for perimeter intrusion detection for many years. Leaky coaxial cables are used to guide a low VHF Radio Frequency (RF) field in an area where disturbance detection is required. Any intrusion in this area disturbs the RF field, and presence can be detected and alarms triggered.
Prototype development and testing of a landslide detection system was undertaken in conjunction with Transport Canada, CP, CN, and Senstar Corporation between 1989 and 1992. Although promising, the project was terminated due to lack of funding.
Through a partnership arrangement with CP and Science Applications International Corporation (SAIC) it is proposed to build upon and refine the prototype developed by Senstar, which would provide not only rockfall or landslide detection but also include a means of detecting a washout condition.
The ability to detect slide and washout conditions would be effective. The cost of implementing this technology, the technological risk involved and its delivery would all be moderate.
4. Seismic Trigger (Accelerometer)
Accelerometers have been used by railways to detect seismic activity (i.e. earthquakes) which may damage structures and trigger landslides. Accelerometers are extremely sensitive instruments designed to directly measure the acceleration of the ground surface. When employed as warning devices, due to train induced vibration, threshold values of 5% g. (forces related to acceleration due to gravity) to 20% g. are commonly used to filter extraneous noise.
Although deformations associated with embankment instability may not exceed commonly employed threshold values, the accelerometer option is not being discounted as an effective means of determining washout or landslide conditions. CN is exploring the possibility of applying this technology and revising the threshold values, in conjunction with circuitry which will ignore alarms when train presence is detected. This train presence cutout feature will allow fine-tuning of seismic trigger sensitivity to detect minimal ground disturbances including falling rock and subgrade slip-out.
The ability to detect slide and washout conditions would be effective. The cost of implementing this technology would be moderate to high. The technological risk involved and its delivery would be moderate to difficult.
5. Slump\Washout Detector (WOD)
The slump/washout detector installed at mile 106.14 on the Ashcroft Subdivision consists of a series of short pieces of rail buried vertically in the area of ground instability. A #14 gauge trip wire is threaded through a hole drilled in each rail section and forms part of a 12V DC relay loop circuit.
Main track vertical rail sections consist of two rails 3 feet 2 inches long, welded back to back weighing 240 pounds, and spaced every 10 feet over a distance of 300 feet. The rail sections are buried to a depth of 2 feet below ground level and 4 feet from end of tiers. Under a significant ground movement condition, the rail(s) will move and break the trip wire, initiating train movement protection.
Breakage of the trip wire will de-energize the adjacent track circuit and cause a Rule 429 aspect of the Canadian Rail Operating Rules (CROR) to be displayed on signals governing movements into this area. A slide fence activation indication will be sent to the Rail Traffic Control (RTC) office, and an emergency track condition message broadcast over a talker radio (which broadcasts a vocal warning).
The ability to detect slide and washout conditions would be partially effective. The cost of implementing this technology and the technological risk involved would be low, and its delivery would be simple.
It is intended that test projects be conducted in the fall and that further requirements for introducing technologies into operation be examined at that time.
R94D0033 - Dangerous Good Leak - Canadian National Yard Assignment No. 0703 - Mile 132.8, Saint-Laurent Subdivision - Montreal, Quebec - 27 January 1994 (R97-03)(R97-04)
TSB Full Text Report (R94D0033):
http://www.tsb.gc.ca/eng/rapports-reports/rail/1994/r94d0033/r94d0033.asp
TSB Recommendation R97-03
Susceptibility of Stubb Sill Tanks - (Action Required, as presented in the TSB Report)
The Board recommends that:
The Department of Transport require that federally regulated Canadian railways:
- implement an awareness program on the susceptibility of stub sill tank cars to cracking, especially if subjected to abnormal impact loads and stresses in cold temperatures, for all employees engaged in the movement of freight cars;
- establish a procedure which would allow employees to report stub sill tank cars suspected of having been subjected to abnormal impact loads and stresses; and
- perform a special inspection on those stub sill tank cars reported as having been subjected to abnormal loads and stresses before the cars are allowed to continue in service. (R97-03)
Transport Canada's Response (R97-03)
(signed by Minister on August 26, 1997)
The Department of Transport is redrafting the Transportation of Dangerous Goods Regulations. One of the changes will have an impact in the area addressed in the recommendation. It is the requirement that a means of containment which has been built to a designated standard, such as a railway tank car, be in compliance at all times and not only at the time of its scheduled inspection.
The Department has difficulty with the word "require" in the recommendation. The meaning we give to this is that the recommendation seeks regulation to put a), b), and c) into effect. The Department does not agree that there should be activity specific regulations. The more general regulatory requirement of "in standard" being imposed through the "clear language regulations" will ensure appropriate actions by the railway companies.
Specific comments on each of the three items follow:
Item a)
The Department is convinced that the railways are aware of the problems which have been identified with stub sill tank cars and will confirm this through the Railway Association of Canada (RAC). The Department is meeting with the RAC on September 5th to discuss the redrafted Transportation of Dangerous Goods Regulations and has invited representatives of the Transportation Safety Board (TSB) to attend. All railways operating in Canada have been invited to the meeting. In addition, the Department will prepare an article for the next TDG Newsletter on impacts in cold weather and will provide reprints to the RAC.
Item b)
The Department will raise this proposal at its meeting with the RAC but does not intend to establish a procedure through regulation.
Item c)
The Department is working to better understand the effect of various types of stresses and once this is known it will be shared with the United States Federal Railroad Administration (FRA) and North American industry. Inspections by railway personnel are anticipated as a result of the new requirement relating to a tank car having to be in standard before it can be moved by a railway company.
TSB Recommendation R97-04
Special Inspections of Stub Still Tanks - (Action Required, as presented in the TSB Report)
The Board recommends that:
The Department of Transport, in consultation with the United States Federal Railroad Administration, encourage the adoption, by American railway companies, of special inspections of stub sill tank cars suspected of being subjected to abnormal impact loads and stresses. (R97-04)
Transport Canada's Response (R97-04)
(signed by Minister on August 26, 1997)
The Department works extensively with the United States Federal Railroad Administration to progress railway safety in North America, however, the Department does not work directly with American railway companies to attempt to affect their actions. The Department will ensure that the FRA is aware of both the concerns of the TSB and Transport Canada initiatives in this respect as part of our on-going consultations.
R96C0172 - Main Track Collision - Canadian National - Train 117 and an Uncontrolled Movement of 20 Cars - Mile 122.9, CN Edson Subdivision - Near Edson, Alberta - 12 August 1996 (R97-05)(R97-06)
TSB Full Text Report (R96C0172):
http://www.tsb.gc.ca/eng/rapports-reports/rail/1996/r96c0172/r96c0172.asp
TSB Recommendation R97-05
Variability in Braking Effectiveness - (Action Required, as presented in the TSB Report)
The Board recommends that:
The Railway Association of Canada promote, among its members, employee understanding of the wide variability in hand brake effectiveness (particularly on Government grain covered hopper cars) and the resultant need for extra vigilance in car securement. (R97-05)
Transport Canada's Response (R97-05)
(signed by Minister on December 12, 1997)
Transport Canada understands that the Railway Association of Canada (RAC) will be responding directly to the Transportation Safety Board (TSB), however, the Department notes the recommendation. Transport Canada is planning to meet with the TSB, as well as representatives of the RAC and the Railway Research Advisory Board, to discuss additional measures which could be taken to better understand the variability of hand brakes.
TSB Recommendation R97-06
Adequacy of Rail Safety Regulatory Overview - (Action Required, as presented in the TSB Report)
The Board recommends that:
The Department of Transport develop and implement policies and procedures for a national audit program that will effectively evaluate the railways' ability to maintain national safety standards. (R97-06)
Transport Canada's Response (R97-06)
(signed by Minister on December 12, 1997)
The Department accepts the recommendation and will develop and implement policies and procedures of such a program commensurate with a performance-based approach and risk assessment practices.
As you are aware, the re-introduction in the House of Commons of amendments to the Railway Safety Act will be delayed to allow more time to examine whether further legislative adjustments are required to ensure that the Department takes every measure necessary to improve safety. This includes examining mechanisms for overseeing safety and regulatory compliance. This report will be completed by January 31, 1998.
R97H0009 - Interim Rail Safety Recommendation concerning rail passenger safety practices on Via Rail (R97-07)
The Board has recommended, as a matter of urgency, that:
The Minister of Transport require that VIA Rail complete its implementation of those short-term measures necessary to improve rail passenger safety within 30 days. (R97-07)
Transport Canada's Response (R97-07)
(signed by Minister on December 12, 1997)
Transport Canada accepts the interim safety recommendation provided by the Board concerning VIA Rail's operations. The Department immediately followed-up on this recommendation with VIA Rail. VIA Rail committed to implement all measures within the specified time frame of 30 days.
In addition, Transport Canada took the following safety actions:
- A Notice seeking formal assurance of VIA's plans to upgrade passenger equipment and signage.
- A Notice and Order under Section 31 of the Railway Safety Act, which precludes VIA from operating under conditions where a safety device has been disabled.
- A Safety Direction under Part II of the Canada Labour Code reminding VIA of their responsibility to ensure employees are adequately trained with respect to safety issues that may affect them.
On a final note, the Department has performed inspections to monitor progress and will continue to verify the implementation of safety measures recommended by the Board.