Abstract: A method for construction of a concrete platform for use in slab track railroads, comprising supporting a tie plate and rail on a concrete form for casting the concrete platform. The concrete form includes a horizontal form positioned below the tie plate, that supports a cast in place fastener system that is imbedded in the surface of the concrete platform and secures the tie plate to the concrete platform. The horizontal form comprises a removable or sacrificial insert that is cast into the surface of the concrete platform. Materials such as expanded polystyrene can be used to make sacrificial inserts that can be removed by dissolving with solvents such as dibasic esters. After the concrete platform is cast, the removable insert is removed and the resulting cavity is filled with a filler material, all without the need to disassemble the tie plate and rail.