36 CFR §64.2

1. (a)Abandoned Railroad Rights-of-Way. An abandoned railroad right-of-way is the real property used for or formerly used for the operation of railroad trains by a common carrier railroad, upon which the railroad company has, or will cease operations and sell, or otherwise dispose of the company's interest in the real property.
2. (b)Project Applicant. Federal, State, or local governmental agencies.