Define maintenance-of-way (MOW) and its scope.

• A. Work performed only on rolling stock to keep trains running.
• B. Inspections performed by a supervisor on the office area.
• C. Projects to upgrade signaling systems with no track work.
• D. All activities that maintain the track, right-of-way, and supporting infrastructure, including inspection, repair, and replacement.

Answer: (D)

Maintenance-of-way is the broad set of activities that keep the railroad’s track, the right-of-way, and the supporting infrastructure in proper condition. It covers inspecting those elements, performing repairs, and replacing components as needed to ensure safe and reliable operation. This means not just the rails themselves, but the ballast, ties, fasteners, switches, drainage, signaling-related equipment tied to the track, and other structures that support movement and access along the corridor.

That’s why the correct choice is the option that describes all activities that maintain the track, right-of-way, and supporting infrastructure, including inspection, repair, and replacement. The other options focus on areas that aren’t the scope of maintenance-of-way: rolling stock maintenance deals with the vehicles themselves, office-area inspections are administrative rather than physical track and ROW care, and signaling upgrades without any track work aren’t maintaining the track or its immediate surroundings.