I think that's probably a question better asked to the department about where they're seeing deficiencies, but one of the items you mentioned earlier was setting standards on follow-ups. While they are doing follow-up and making sure corrective actions are taken, they're not really setting a timeline. It is left to the inspector to go back at some point in time. More regular, focused review or follow-up would keep the pressure on railway companies to increase and enhance safety.
Most of the activities about oversight are making sure that railway companies are complying with the requirements, but compliance isn't enough. You have to make sure there's actually an improvement in safety. It's hard to pinpoint, because I think every area might have a different deficiency, depending on things identified in inspections and so on.
It's hard for me to give you a list, but it's about making a more timely follow-up on deficiencies that have been identified.