At each grade crossing of a highway and a railroad, the railroad shall: Keep its roadbed and the highway in proper repair so as to provide absolutely safe and easy approach to and crossing of the tracks; or Subject to approval by the Administration, construct a railroad grade separation. The Administration may abandon, relocate, construct, or reconstruct any railroad grade crossing or railroad grade separation that is dangerous or inconvenient for public travel. If a railroad grade crossing is dangerous or inconvenient for public travel, the Administration may construct a railroad grade separation. The Administration may require the railroad to do any of the work needed under this section, on the terms and conditions that the Administration specifies. If the railroad fails to do any work required of it under this section, the Administration may perform the work itself and collect the railroad’s share of the cost from the railroad.