For purposes of the Nebraska Shortline Rail Modernization Act:

(1) Department means the Department of Revenue;

(2) Eligible taxpayer means any shortline railroad company located wholly or partly in Nebraska that is classified by the federal Surface Transportation Board as a Class III railroad;

(3)(a) Qualified shortline railroad maintenance expenditures means gross expenditures for railroad infrastructure maintenance and capital improvements, including, but not limited to, rail, tie plates, joint bars, fasteners, switches, ballast, subgrade, roadbed, bridges, industrial leads, sidings, signs, safety barriers, crossing signals and gates, and related track structures owned or leased by a Class III railroad.

(b) Qualified shortline railroad maintenance expenditures does not include expenditures used to generate a federal tax credit or expenditures funded by a federal grant; and

(4) Taxpayer means any individual, corporation, partnership, limited liability company, trust, estate, or other entity subject to the income tax imposed by the Nebraska Revenue Act of 1967 or any tax imposed by sections 77-907 to 77-918 or 77-3801 to 77-3807.