How close is living too close to train tracks?

Asked by msh (4270) January 12th, 2016 from iPhone

A set of train tracks runs by an area where a friend lives. Her house is farther in the ‘settlement’, not near to the tracks physically, but the train whistles for the major crossings is like clockwork. A busy train yard is located on the western side of the city- thus the train traffic.
Recently (2years?) a company, hoping to cash in on student housing fees, built a series of apartments less than – say -125 feet from the sets of triple, down to double tracks. (an extra lane to hold an operating train, to let another train pass, if needed.) This is not part of University housing.
Inside the housing area where my friend resides, some of the homes were built in the 1940’s. Their placement is a good 300 feet away from the tracks along one block.
Other than the chemicals used to strip the foliage and damn near everything else from the runoff, I was wondering about something while sitting at the crossing for a train.
Over time, would the tremendous vibrations from the cars on the railways, each with their own vibration, whole train lengths -worth , have an effect when placing these housing areas in such close proximity?
For the older homes in the area does it effect them at all? Would the foundations shift? Some houses do have basements. Aside from the thought of railway accidents, would these students have to worry about the rocking and rolling so close next to them in quickly constructed apartments?
How much impact do railways have on those living close, when thinking of the results of years of vibration near housing foundations?