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OCR for page 82
82 Shared Use of Railroad Infrastructure with Noncompliant Public Transit Rail Vehicles: A Practitioner's Guide overcome some preconceptions. More research and cumulative performance experience may be essential to effect a change. These impediments are the primary reason that the concept has not been more readily embraced, as evidenced by the number of transit agencies that opted for con- ventional rail systems and other projects that were simply stopped. Liability: common to any passenger/freight operation (not unique to shared-track), but there is a lack of precedent and actuarial data for shared-track, so at the very least the unknown financial impacts may drive up the cost. Safety issues: disparate speeds and operating weight, structural incompatibility in multiple dimensions, frontal configuration, service characteristics. Waiver process: long, complex process; each is unique; may require external legal and techni- cal support at extra cost; invites external parties to evaluate project. FRA Part 238 and 236 compliance (see waiver process): cost and legal implications. Regulatory unfamiliarity: officials are unfamiliar with light passenger rail equipment, its per- formance capabilities and operations. More exposure to this technology and standardized vehicle design would aid understanding. Risk analysis: application of risk analysis methodology and interpretation of results is some- what esoteric; validated data to quantify risk is lacking; modeling risk events is a complex affair; some have a natural inclination to dismiss risk concerns while others display a tendency to overstate them; one school of thought places excessive faith in risk management while another has insufficient faith. The probabilistic aspect does not satisfactorily address a "night- mare scenario" event. There is simply less comfort in calculating a one-in-a-billion chance of an accident event every 10 years. Regulators can more easily understand that if an accident occurs, then passengers are protected. Lack of sufficient accident data: a perverse and ironic insufficiency of hard data compounded by lack of collision modeling via computer or field test results. Rigid temporal separation: is a "zero-sum" game. If the one mode gains the other loses. Potential for unknown outcomes: for planners, policy makers and all stakeholders, the planned or desired outcome of the effort is not assured. Costs, schedules, and technology choices are all subject to review and approval by the FRA, and may be amended at any stage in the process. Lack of strong voice: the novel and niche role of shared-track needs strong local or state advo- cacy to support and encourage it. The participation of project champions and likely benefici- aries (e.g., shortline operators) should be solicited. No corridor philosophy (similar to highway or air traffic): railroads are seen as exclusive cor- ridors for conforming equipment, not as corridors or highways available to different vehicles sharing the same route. Local issues: particularly local speed restrictions for railroads enacted while plans are evolving can complicate or restrict the service plan; grade crossing impacts, associated horn-blowing noises, and ambient noise and operational impacts are also a concern. Shared Track--The Potential Market Track sharing between mainline trains and light passenger rail cars serves a niche market between commuter rail and a stand-alone light rail system. Viable operations in North America typically entail allowing a small number of branch line freight trains to operate over a line that is converted for medium-frequency light passenger rail use at limited speeds. The community will benefit or be impacted by the advantages or disadvantages arising from shared-track, which are summarized here. There is no implied weighting of these factors, they are simply identified. A transit agency and various stakeholders should assign the relative value (positive or negative) to each.