The gist as I understand is that pensioners were promised a 8.5% return (which didnt happen) and (some?) retirees are able to withdraw their current value in their pension in full. There is talk of reducing benefits, which is causing a situation much like a run on banks to occur.
I've seen a few proposed solutions such as having the state of Texas help pay, to pillaging funds from DART (public transit), to tax increases.
It is a complete mess, and PR must be in such a bad position. In Dallas' case, it is obviously corruption that caused the problem, with no penalty, and the only recourse is to penalize those that did not cause the problem. Seems like PR is in a similar yet more dire situation.