Hi Laci,
I've seen very simple procedures of having a bin or table at the end of each station (or line) where either the station worker or a dedicated quality person will review and confirm to send to scrap, and literally just rolled down to the scrap area. For tracking, bar codes are used in tandem with either manual paperwork or a computer driven tracking system. Quick and easy to implement and do, and helps keep the supervisor of the line checking the workmanship, without having to be obvious.
Hope this helps!
Donna