I would expect that it will not be pleasant and the chain reaction will make the news. It should be noted that this did happen in the not too distant past with the rail system in the US. I know of at least one car filled with soybeans that sat on some side track in the middle of nowhere for multiple (6+) months.

Story: At one point, I worked at a company that did clinical trials. They had this great computer controlled track with multiple cars that delivered all the samples to each lab (1 self powered car per sample). It could go straight up / flip over and the sample never tipped.

One day, a sample didn't arrive at one of the labs. It was frozen and we needed to get to it before it thawed as it, shall we say, wasn't a liquid. We traced the track an finally found it Alien's style when I turned a slow 180 with the flashlight as I was about half in the ceiling standing on a ladder. It had stopped because a rather large rat had not avoided getting hit by the car. I did not, at any point, think this was a logical consequence of my choice of professions.