It's not actually that hard to fix. We know how to regulate large industrial operations that use dangerous substances. The problem is that we don't use those regulations, we use a whole different set of regulations that were created by people whose specific intent was to make construction uneconomical.

Example. One of the problems that have occurred is that the regulations change during construction. You spend a billion dollars on construction and then the regulations change and you have to start over. The simple change that the construction rules a plant is evaluated under are the ones in effect when construction began would solve half the problem in itself.